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近20年苏锡常地区土地利用格局变化及其驱动因素分析 总被引：12，自引：1，他引：12
土地利用变化是全球生态环境变化研究的重要组成部分。苏锡常地区作为我国传统的人口密集区和土地高度集约化利用区，土地利用历史悠久。1980年以来, 苏锡常地区社会经济发生了巨大变化，从而引起土地利用/土地覆盖格局的相应变化。本文利用1980年、1995年和2000年的Landsat TM数据对苏锡常地区的土地利用情况进行测量，取得研究区土地利用变化的转移矩阵，据此对苏锡常地区1980年～2000年的土地利用变化情况进行分析，揭示土地利用变化的驱动因素，以得到耕地、林地、草地、建设用地、水域和未利用地变化的驱动因子，为协调土地资源与社会经济发展的关系、制定合理的土地资源利用体系、促进土地资源和社会经济的可持续发展提供依据。研究表明：1980年～2000年苏锡常地区土地利用变化的驱动因素受人文因素和自然因素的共同影响，但主要是受社会经济政策因素影响，自然因素具有相对稳定性。 相似文献
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Kalpana Luthra Suman Vasisht Shivani Chhabra K. R. Raju D. P. Agarwal S. C. Manchanda L. M. Srivastava 《Indian journal of clinical biochemistry : IJCB》1998,13(1):12-19
Lipoprotein Lp(a) excess has been identified as a powerful predictor of premature atherosclerotic vascular diseases. To evaluate
this in a North-Indian population, 130 CAD patients and 130 controls were analyzed. The size of the apo(a) phenotypic isoforms
was inversely proportional to Lp(a) concentrations. The mean concentration of Lp(a) in the CAD patients was 42±34 mg/dl whereas
in the normal subjects it was much lower, 27±27 mg/dl. 157 subjects out of the total 260 subjects showed plasma levels of
>20mg/dl. The frequency of high Lp(a) levels was much higher in patients(73%) than controls (43%). These data suggest (1)
that there is heterogeneity of the Lp(a) polymorphism, (2) Higher Lp(a) levels were found in patients than in the controls,
(3) Patients showed 1.5 fold increase in Lp(a) levels as compared to the controls. We conclude that low molecular weight apo(a)
isoforms are significantly associated with increased risk of CAD in the North-Indian population. 相似文献
4.
壳斗科三棱栎属Trigonobalanus Forman含3种,即:三棱栎T．doichangensis,南美三棱栎T．excelsa,轮叶三棱栎T．verticillata。通过用光学显徽镜、扫描电子显微镜、激光共聚焦显微系统及透射电子显微镜对3个种的花粉进行观察并比较分析,确认它们分别属于显然不同的3个类型:(A)花粉粒为扁球形,赤道面观宽椭圆形,极面观钝三角形;孔在角上,内孔具明显的孔室,孔缘加厚;外壁覆盖层无穿孔,孔区外壁-2(从化学分层)特厚;表面具疣波状纹饰。三棱栎为此类型。(B)花粉粒为长球形,赤道面观长椭圆形,极面观近三角形或三瓣形;萌发孔多为3拟孔沟(-3沟),位于三角形的边上;外壁覆盖层具穿孔,表面具粗瘤(疣)状纹饰。南美三棱栎为此类型。(C)花粉粒近球形、赤道面观近圆形,极面观3裂圆形,3孔沟在边上;覆盖层具穿孔;表面具小瘤和蠕虫状短条纹饰。轮叶三棱栎为此类型。以上3个种的花粉粒形状、萌发孔、外壁结构、表面纹饰等特征,特别是萌发孔特征、类型及位置,在壳斗科的花粉形态中表现出较大差异,越出了种间的区别,故笔者认为K．C. Nixon和W．L. Crepet将3个种分立为3个单型属是自然合理的,即:Formanodendren(F．doichangensis(Camus)Nixon et Crepet), Colombobalanus(C. excelsa(G．Lozano,J．Hdz-C．et J．Henao)Nixon et Crepet),Trigonobalanus(T．verticillata Forman)。 相似文献
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报道了C_(60)球烯的制备分离过程,并对所获得的纯C_(60)粉末样品和膜样品进行了~(13)C核磁共振,傅里叶红外以及Raman谱研究.结果表明:C_(60)样品在红外有4个吸收峰,分别位于528、578、1182、1429cm~(-1)处;在Raman谱中观察到3个峰,分别位于273、469、1465cm(-1)处;~(13)C核磁共振谱则表明在143.2 ppm化学位移处有一单峰,这些都与理论计算值相符,很好地证实了C_(60)的全碳和高度对称的球形结构. 相似文献
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Seema Gupta Rajesh Pandey Ranjan Katyal H. K. Aggarwal R. P. Aggarwal S. K. Aggarwal 《Indian journal of clinical biochemistry : IJCB》2005,20(1):67-71
The present study was conducted to evaluate some of the components of antioxidant defense system and oxidative damage in 20
male patients of alcoholic liver disease (ALD). The results were compared with 20 healthy male smokers and 20 healthy male
non-smokers volunteers. Patients were subjected to detailed clinical examination and laboratory investigations. Blood samples
were collected for estimating reduced glutathione (GSH), total thiols (T-SH) malondialdehyde (MDA), transaminases (AST, ALT),
glutathione-S-transferease (GST) and gammaglutamyl transferase (GGT). Serum aspartate amino transferase (AST)/alanine amino
transferase (ALT) ratio was significantly (p<0.01) reduced in ALD patients as compared to the controls. However, the core
of utility of MDA and GST was found to be significantly (p<0.01) increased in ALD patients compared to controls. There was
a significant negative correlation of MDA with both GSH and TSH. Plasma GGT levels were significantly (p<0.01) increased in
alcoholics and the enzyme showed a significant positive correlation with MDA. These results give enough evidence of increased
oxidative stress and compromised antioxidant defense system in patients with ALD. 相似文献
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K. S. Motghare Anil Bhutey B. B. Murrhar Madhur Gupta A. W. Meshram Y. Balsubramanium 《Indian journal of clinical biochemistry : IJCB》2001,16(2):213-215
With the growing interest in the concept of free radicals in the pathogenesis of myocardial ischemia, it was thought worthwhile
to study the changes in lipid peroxides and antioxidant enzyme glutathione peroxidase (GPx) in ischemic heart disease (IHD).
The study was carried out on 76 patients of IHD-38 of acute myocardial infarction (AMI) and 38 of stable ischemic heart disease
(SIDH). They were age and sex matched with 38 normal healthy controls. A significant increase (p<0.001) in lipid peroxides
as malondialdehyde (MDA) (5.9±0.7 mmol/L) and a decrease in GPx (24.6±2.2 U/gmHb) was found in patients of AMI when compared
with controls. There was no significant difference in these values in SIHD. Thus this study confirms the earlier findings
that MDA and GPx are useful parameters in IHD and their magnitude is dependent on severity and/or duration of ischemia. We
suggest that these tests would be of use in smaller institutions with limited facilities. 相似文献
8.
水氮互作对水稻茎叶中氮形态及部分无机元素含量的影响 总被引：4，自引：0，他引：4
采用聚乙二醇(PEG6000)模拟水稻干旱胁迫方法，研究了水氮逆境下不同品种水稻茎叶氮素形态及部分无机离子含量的变化．研究结果表明，干旱胁迫使水稻茎叶中可溶性蛋白(SP)、全P、Na^ 含量降低，而对水稻体内全氮(TN)、蛋白态氮(prN)、非蛋白态氮(NprN)及K^ 、Ca^2 、Mg^2 含量的影响因品种而异，且与供氮水平有关．干旱胁迫下，氮素营养可明显增加水稻茎叶可溶性蛋白(SP)、全氮(TN)、蛋白氮(prN)及非蛋白氮(NprN)、全P、K^ 、Na^ 含量，但对Ca2^2 及Mg^2 含量的影响具有品种间差异性。 相似文献
9.
芍药属的研究(1)——国产几个野生种核型的报道 总被引：1，自引：0，他引：1
In the present paper 8 species with 15 populations of the genus Paeonia L. (if P.
papaveracea and P. japonica are recognised as species) were collected from Sichuan, Shaanxi
and Hebei provinces (see the Appendix for detail of the materials). The micrographs of their
somatic metaphase (also Mii in the case of P.veitchii) are shown in Plates 1-4, the karyo-
type formulae, ranges of chromosome length and classification of karyotypes according to Steb-
bins (1971) are shown in Table 5: the idiograms in Figs. 1-2, and the parameters of chromo-
somes in Table 1-4. The essential points are mentioned as follows:
(1) Chromosomes of the various species in the section Modan have so far been examined
and they are all diploid, the two species in the section Onaepia are also diploid, and thus
tetraploids exist only in the section Paeonia.
(2) Chromosomes in the genus Paeonia are relatively stable except for the differentiation
of ploidy. The karyotypes (Table 1-4) show no differences among different taxa in Sect.
Modan and the same can also be said about the taxa in Sect. Paeonia (Table 1). Not only
are the karyotypes very similar, but also among the members within either section have the
same parameters of chromosomes, and, differences, if occur, are not statistically significant.
Between the two sections, however, the situation is different. The arm ratios of the first pairs of
chromosomes in Sect. Modan are 1.53, 1.52 and 1.48 (Table 1), but those in Sect. Paeonia
are 1.12-1.28 (Table 2-4), 95% confidence limits are 1.46-1.60 for the section Modan and
1.07-1.28 (1.21-1.35 only for PB85078) for the section Paeonia, not overlapping, which indi-
cates that the two sections have differentiated in respect of the first pairs of chromosomes.
(3)The population PB85024, which belongs to the P. obovata complex, has a karyotype of
2B (stebbins, 1971), which is a new one in the genus Paeonia. This karyotype is a stable one,
for several individuals in the population are uniform in this respect, which shows that Steb-
bins’ (1971) generalization that all the species in Paeonia have 2A does not hold true.
(4) Three populations of P. obovata complex studied in this work from Sichuan and
Shaanxi are all tetraploids, and one from Hebei is a diploid. From the present work and
the previcus reports, the materials from Japan and Korea, no matter whether flowers are pink
or white, are diploids, those from Heilongjiang Province (with both pink and white flowers)
(Liu Ming-yuan, personal communication) and from Heibei Province (with pink flowers)
in China are also diploids, the one from Sakhalin (pink flowers) is tetraploid, those from
Priamur of the Soviet Union are a tetraploid (with white flowers) and a diploid (with pink
flowers), and those from Shaanxi (the Qinling Range) and western Sichuan (with both pink
and white flowers) are all tetraploids. As far as we have now known, ploidy in this parti-
cular complex is correlated with the geographical distribution: diploids are found in the cen-
tral part, tetraploids occur in the northern limits, and in the south letraploids are the only
cytotype.
(5) The materials of P. mairei from western Sichuan and Shaanxi (the Qinling Range)
are found all to be tetraploids, which shows that two cytotypes, diploid and tetraploid, exist in
this species, but the geographical distribution pattern of these two cytotypes is to be revealed
in the future investigation. 相似文献
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C. E. J. Udiong A. E. Udoh M. E. Etukudoh 《Indian journal of clinical biochemistry : IJCB》2007,22(2):74-78
The prevalence of abnormal thyroid hormone levels in diabetes mellitus in Nigeria is not well described. To determine the
incidence of abnormal thyroid hormone levels in diabetics in Calabar, Nigeria, fasting blood samples from 161 diabetic subjects
and 105 non-diabetic controls were analysed. Free thyroxine (FT), thyroid stimulating hormone (TSH), total triiodothyronine
(T3) and total thyroxine (T4) kits obtained from Biomerica Inc. of USA were used for the analysis. TSH levels (1.80±1.62) in diabetics were significantly
lower (p=0.016) than the level in non-diabetic controls (2.34±1.24). Male diabetics had lower (p<0.05) levels of TSH (1.192±0.68
miu/ml) than diabetic females (1.90±1.70 mlu/mt). The level of T3 in diabetic males (125±97ng/ml) was higher than the level in females (98±75ng/dl). TSH (F=2.74, p=0.049), T4(F=56.87, p=0.001), T3(F=56.44, P=0.001) in diabetics and FT4 (F=5.74, p=0.002) in controls showed significant variation with the ages of the subjects. Out of 161 diabetics subjects studies
26.6% had low plasma thyroid hormone levels (FT4>2.01 ng/dl). This study has shown a high incidence (46.5%) of abnormal thyroid hormone levels among the diabetics in Nigeria
(hypothyroidism 26.6%, hyperthyroidism, 19.9%). The prevalence of hypothyroidism was higher in women (16.8%) than in men (9.9%),
while hyperthyroidism was higher in males (11%) than in females (8%). This study has defined thyroid function status of diabetics
in Calabar, Nigeria probably the first of such work in Africa. 相似文献
11.
To elucidate a higher rate of premature cardiovascular disease (CVD) in Asian Indian descendants (Roma) in Slovakia, we investigated frequency distribution, correlates and relationship of lipoprotein(a) [Lp(a)] to family CVD risk factors in Roma children and their Caucasian neighbors. The study sample consisted of 607 healthy children aged 7–18 years (55% Roma, 48% male) as part of the biracial (Roma–Caucasian) Slovak Lipid Community Study. Overall, frequency distribution data of Lp(a) were highly skewed to low concentrations, with markedly higher Lp(a) levels in Roma than in Caucasian children (median and range, mg/dL: 14.5; 0–159.2 vs 6.2; 0–112.3, P < 0.001), regardless of age and gender. Lp(a) was positively correlated with apo B (0.159, P = 0.004) in Roma, and LDL cholesterol (0.170, P = 0.005) in Caucasian children. In addition, daily income of the family was negatively related with Lp(a) in Roma (−0.134, P = 0.036) while positively in Caucasians (0.136, P = 0.047). For both race groups, no significant association was found between Lp(a) and age, body mass index, mean arterial pressure, smoking, and physical activity. Also, no significant relationships were examined between serum Lp(a) levels >30 mg/dL in children and family CVD risk factors, except for diabetes mellitus in parents of Caucasian origin (OR 4.46; 95%CI: 1.23–16.20). In a multivariate analysis, daily income, LDL cholesterol or apo B explained ~7% of the variance of Lp(a). This study suggests a significantly higher serum Lp(a) levels in Roma than in Caucasian children and a small effect, in general, of relevant CVD risk factors on the variation of Lp(a) levels in childhood. 相似文献
12.
血管紧张素原基因CD235Met-Thr变异与高血压脑梗塞发病的相关性 总被引：1，自引：1，他引：0
探讨汉族人群血管紧张素原(AGT)基因CD235Met-Thr变异与高血压合并脑梗塞发生的关系.采用突变基因分离聚合酶链反应(MS-PCR)方法检测82例高血压合并脑梗塞患者(BI)、67例单纯高血压患者(EH)和95例健康对照者(C)的M235T等位基因型.BI组AGT基因T/T基因型频率和T等位基因频率(分别为0.720和0.811)显著高于C组(分别为0.516和0.700,P＜0.05)和EH组(分别为0.537和0.716,P＜0.05).结果提示,AGT基因CD235Met-Thr变异增加了汉族人群高血压合并脑梗塞发病的易感性. 相似文献
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本研究基于各国的技术需求评估报告和合作专利分类系统,开展了“一带一路”共建国家气候变化技术需求的特征评估。研究发现,66个“一带一路”共建国家共提及了726项气候技术需求,其中减缓262项、适应464项。可再生能源发电是减缓的优先需求,农林牧副渔生产中的适应技术是适应的优先需求。但是,不同区域的减缓技术需求呈现异质性,适应技术需求呈现共性。非洲地区的优先减缓需求是可再生能源发电、非化石燃料技术和土地部门的减缓技术,亚洲地区为可再生能源发电和具有减缓潜力的燃烧技术,拉丁美洲和大洋洲为道路交通部门的减缓技术。为促进中国向“一带一路”区域的气候技术转移与南南合作,我国提供的重点技术应与各国的重点需求相匹配、提升技术信息的透明性并强化需求与方案的国别研究。 相似文献
15.
纳米氧化锌对人肺腺癌细胞A549的毒性 总被引：3，自引：0，他引：3
探讨纳米氧化锌（ZnO）对体外培养的人肺腺癌细胞A549的生物学效应。使用原子力显微镜（AFM）、透射电镜（TEM）和X射线衍射仪（XRD）研究纳米ZnO颗粒物的理化性质。然后,使用0mmol/L、0.1mmol/L、0.5mmol/L、1mmol/L、5mmol/L、10mmol/L的纳米ZnO处理体外培养的人肺腺癌A549细胞,MTT 法测定细胞生长活性。并且测定1mmol/L 纳米ZnO染毒24h后细胞培养液上清中,乳酸脱氢酶（LDH）和胞内的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）的活性以及丙二醛（MDA）的含量。使用透射电镜和流式细胞仪检测细胞凋亡的情况。荧光染色检测细胞产生活性氧（ROS）的生成。实验所用的ZnO纳米颗粒为长75 nm、直径20nm的针状纤锌矿晶体。细胞实验结果表明,纳米ZnO颗粒对A549细胞的生长活性具有明显的抑制作用,存在剂量－效应关系。培养液上清中LDH活性显著升高（P < 0.05）,胞内CAT活性显著下降、MDA含量显著升高（P < 0.01）,但SOD活性下降不明显。荧光染色检测发现染毒后A549细胞出现细胞凋亡,而且细胞内ROS的生成与纳米ZnO存在剂量－效应关系。结论是纳米氧化锌诱导人肺腺癌A549细胞产生活性氧,引发细胞凋亡,并产生细胞毒性。 相似文献
16.
用单光子吸收法（ＳＰＡ）对杭州市汉族５０岁以上的８０例非胰岛素依赖性糖尿病（ＮＩＤＤＭ）患者和年龄、性别与ＮＩＤＤＭ患者相配对的４３１名正常人的前臂尺、桡骨骨密度（ＢＭＤ）进行测定，发现女性轻中型和重型组、男性重型组ＮＩＤＤＩＭ患者的尺桡骨平均ＢＭＤ显著地低于正常人（Ｐ＜０．０１）；本组ＮＩＤＤＭ患者（男女合计）的一般性骨质疏松症（ＧＯＰ）和进行性骨质疏松症（ＰＯＰ）的发病率分别为６３．７５％和８．７５％，与正常人组相比较差异非常显著（Ｐ＜０．０１）；不同病程ＮＩＤＤＭ患者组别间尺桡骨平均ＢＭＤ的差异不显著（Ｐ＞０．０５），提示ＮＩＤＤＭ的病程与ＢＭＤ的相关程度不密切。 相似文献
17.
Anisha Chauhan Nidhi Srivastva Parvesh Bubber 《Indian journal of clinical biochemistry : IJCB》2018,33(4):422-428
Thiamine or vitamin B1 is a well known coenzyme and nutrient necessary for the assembly and right functioning of several enzymes involved in the energy metabolism. The present study evaluates oxidative stress and prevalence of neurodegenerative conditions in the brain following TD. The study was carried out on mice (Musmusculus) in three groups, namely control and thiamine-deficient group for 8 (TD 8) and 10 (TD 10) days. Lipid peroxidation was determined in terms of reduced glutathione (GSH) and thiobarbituric acid reactive substance (TBARS). The level of antioxidant enzymes such as catalase (CAT), glutathione reductase, glutathione peroxidase (GPx), superoxide dismutase (SOD) and glutathione transferase (GST) were measured along with histopathological studies in all the groups. There was significant increase in the TBARS levels in group II (TD 8) and group III (TD 10) animals in comparison to controls (Group I). The GSH levels were found to be lower in both the treated groups. The level of antioxidant enzymes CAT (p < 0.001), glutathione reductase (p < 0.001), GPx (p < 0.001), SOD (p < 0.0001) were found to be significantly reduced in group III (TD 10) in comparison to controls. Histopathological studies showed moderated to extensive neuronal loss in group II and group III in comparison to control group. The increase in LPO and reduction in enzymes CAT, glutathione reductase, GPx, SOD, and GST following TD suggests mitochondrial dysfunction, neuronal loss acute oxidative stress that may impair the functioning of the brain along with the rise of neurodegenerative conditions in the affected animals. 相似文献
18.
《Research Policy》2023,52(6):104784
We explore how multimarket contact (MMC) explains competitors' intellectual property (IP) infringement-litigation dynamics. We build on role congruity theory to propose that the role played by each firm in shared markets generates expectations about their behavior, determining which of the following dynamics arise: mutual forbearance (low probability of IP infringement and high probability of litigation) or mimetic behavior (high probability of IP infringement and low probability of litigation). We look into two possible roles, imitators and innovators, and claim that (1) mutual forbearance dynamics are more likely to arise when firms play the role of innovators, whereas (2) mimetic behavior dynamics are more likely to arise when firms play the role of imitators. We find support for our predictions in a sample of 813 patent infringement cases in the biopharmaceutical industry. Increasing MMC from one standard deviation below the mean to one standard deviation above the mean leads to a 21.6 (20.6) percent decrease in the probability of infringement and a 22.7 (65.1) percent increase in the probability of litigation after infringement when the rival (focal firm) plays the role of an innovator in shared markets. Alternatively, this increase in MMC leads to a 14.3 % increase (no increase) in the probability of infringement and a 5.2 (16.4) percent decrease in the probability of litigation when the rival (focal firm) plays the role of an imitator in shared markets. 相似文献
19.
The present study was carried out to investigate the protective role of Triphala (a combination in equal proportions by weight
of fruit powder of Terminalia belerica, Terminalia chebula and Emblica officinalis) against 1,2-dimethylhydrazinedihydrochloride (DMH) induced Endoplasmic reticulum stress (ER stress) in mouse liver. An oral
dose of 3 mg/kg body wt in drinking water for 5 weeks significantly (P < 0.001) increased the levels of serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase
(SGPT), serum Alkaline phosphatase (ALP) and total bilirubin thus suggesting damage to mouse liver and biliary dysfunction.
The DMH administration invariably led to increase in the liver microsomal proteins of molecular weight of about 29 (ERp29)
and 53 kDa (ERp53) and decrease in the protein of molecular weight of 36 kDa (ERp36) thereby suggesting the interference of
DMH and its metabolites with normal protein biosynthesis and folding, in the reticular membranes of the liver cells thus developing
ER stress. Histological studies show necrosis, large sized hepatocytes with increased N:C ratio, aberrant mitotic figures
and prominent nucleoli in the liver of DMH treated mice. In animals fed 5% Triphala in diet (w/w) during DMH administration,
there was significant decrease in the above changes in the liver suggesting the suppression of DMH induced ER stress in liver.
Triphala significantly (P < 0.05) decreased lipid peroxidation and also the activity of lactate dehydrogenase (LDH) in mouse liver. It simultaneously
increased the level of reduced glutathione (GSH) and the activity of glutathione-S-transferase (GST) thereby suggesting that
it prevents peroxidative damage and also diverts the active metabolites (electrophiles) of DMH from their interactions with
critical cellular bio-molecules which could be responsible for its protective action against DMH. 相似文献
20.
K. N. Dave B. N. Dave F. R. Billimoria M. N. Mehta N. K. Hase 《Indian journal of clinical biochemistry : IJCB》1990,5(2):135-138
Total acetylcholinesterase (AChE) activity was estimated in cerebrospinal fluid (CSF) using colorimetric method in 64 cases
with tuberculous meningitis, (TBM) (n=64), pyogenic meningitis (PM) (n=60) and in controls (n=39) of paediatric age group.
Mean CSF—AChE values of both TBM and PM were significantly higher when compared with controls (p<0.001) but no significant
change between TBM and PM was observed (p<0.01). It is suggested that inflammation of meninges due to the infection may attribute
to a change in the function of blood brain barrier (BBB) causing higher CSF—AChE values in these diseases. 相似文献