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51.
目的:探讨HSP_(27)在消化道癌中的表达状况和意义。方法:收集食道癌、胃癌和大肠癌标本168例,用SP免疫组织化学方法染色。结果:HSP在食道癌、胃癌和大肠癌中的表达率分别为66.04%、37.04%和34.43%;在食道癌中高分化组阳性率(75%)明显高于低分化组(38.46%)。HSP表达与性别、年龄、癌侵润深度、淋巴有无转移的相关性不显著。结论:HSP在食道、胃、大肠癌中表达率依次下降,HSP表达率与癌分化程度有一定相关性。 相似文献
52.
广西植被和植物区系基本特征Ⅰ.自然条件及植物区系的组成 总被引:2,自引:0,他引:2
对广西进行了详细的植物区系调查和植物区系名录整理.结果表明,广西植物区系共含野生维管植物275科、1575属、6826种.其中蕨类植物54科、125属、532种;裸子植物7科、13属、48种;被子植物214科、1437属、6246种.本文简述了与该地区植物区系有关的自然条件,分析了该地区的植被特征,对区系的组成特点进行了初步的统计分析 相似文献
53.
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55.
许昌地区地处伏牛山余脉向豫东平原过渡地带,属暖温带区域.根据吴征锰教授对中国种子植物分布区类型的划分,对本区种子植物的分布区类型的研究发现,本区种子植物各属共有15种分布区类型和15种变型;对其种子植物区系的属组成的初步分析发现,该区植物区系有以下特征:1)以温带性质为主兼有一定热带成分,显示出暖温带与北亚热带过渡交替的特征;2)区系地理成分多样,与其他植物区系问联系广泛;3)植物区系起源古老,存在一些中国特有、残遗属. 相似文献
56.
WANG Liang WANG Lei LI Feng-ting LIU Hua 《重庆大学学报(英文版)》2007,6(4):238-241
A mixed bacterial flora was isolated from the soil of two petroleum-contaminated sites, then cultivated and domesticated in an open environment. The bacteria were used to degrade engine oil in wastewater. The optimum biodegradation conditions for all engine oil concentrations of respectively 489 mg L-1, 1 075 mg L-1 and 2 088 mg L-1 are bacterial inoculum concentration of 0.1%, temperature at 30 °C to 35 °C, pH 7.0 to 7.5, and rotation at 190 r min-1 to 240 r min-1. The second-order kinetic model proposed by Quiroga and Sales describes the characteristics of the biodegradation of the engine oil very well. Engine oil concentration barely changes the growth rate of the bacterial consortium. The mixed bacterial flora has a high biodegrading capability for engine oil. 相似文献
57.
宋才发 《青海师范大学学报(哲学社会科学版)》2004,(1):11-14
中国既是野生植物资源最丰富的国家之一,又是《生物多样性公约》的签字国,国家有关部门已经开始注意到了生物多样性的保护和生态安全保障。我国对植物新品种保护作出了明确的法律规定。必须依法保护农业野生植物,依法引进新鲜植物物种。同时又必须深刻认识外来物种入侵的威胁和危害,对外来入侵物种的危害必须依法治理。 相似文献
58.
白洋淀水生植物区系初步分析 总被引:1,自引:0,他引:1
陈耀东 《中国科学院研究生院学报》1987,25(2):106-113
The Baiyandian Lake lies at 115°56′ E. and 38°55′ N. It is about 8 m above
sea level, with an area about 312 square km. There are abundant aquatic plants here, inc-
luding flowering plants of 30 families, 46 genera, 66 species and 3 varieties besides one in-
troduced species. 32 species are erect ones covering about 48.5% of the total number of species
in this lake, 20 are submerged ones, about 30.3%, 9 are leaf-floating ones, about 13.6% and 5
are floating ones, 7.6%. The soil at the bed of the lake is very fertile and the depth is appro-
priate, favouring various plants. The coverage is large, sometimes it may reach 100%, for
example, in communities of Phragmites communis, Hydrilla verticillata, Hydrocharis dubis,
Trapa bicornis, etc. Although the Baiyandian Lake is located in the temperate zone, the floristic
elements are complex. There are tropic-subtropic elements and elements of high-frigid zone
as well. When compared respectively with the floras of the Lakes Jingbo Lake, Honghu Lake
and Lugu Lake, the flora of this lake is found more similar to that of subtropic Honghu Lake
than to those of the other lakes, which shows that it hase a character transitional between the
south and the north in China. Further studies of the floristic relationships are needed in order
to exploit and use the resources of the aquatic plants in this lake. 相似文献
59.
The Rosaceae is one of the five largest families of Xizang flora, consisting of
30 genera with 242 species, the total number of species is slightly less than those of
Compositae, Graminae, Leguminosae and Ericaceae in Xizang, amounting to 62.5% of
the total number of genera and 28% of the total number of species of the rosaceous flora
in China.
The four subfamilies of Rosaceae including primitive, intermediate and advanced
groups have been found in Xizang. These groups consist of 11 types of floristic ele-
ments, i.e. 4 genera belong to cosmopolitan, 9 genera belong to North Temperate, 3, E.
Asian-N. American, 3 Sino-Himalayan, 3 Sino-Japanesa, 2 Old World Temperate, 1
Temperate Asian, 2 Mediterranean-W. and O. Asian, 1 C. Asian, I Tropical Asian and 1
endemic to China. It is obvious that Rosaceae in Xizang comprises holarctic, Ancient Me-
diterranean and paleotropical elements, among which the temperate components are the
most dominant. The characteristics of the floristic composition of Rosaceae in Xizang
may be summarized as follows:
(1) Xizang abounds in both genera and species of the family which are diverse in
forms, including the primitive, intermediate and advanced groups, (2) The geographi-
cal elements are rather complex, mostly belonging to the temperate, among which the
Sino- Himalayan components and the elements endemic to China are dominant, (3) The
proportion of plants endemic to China and distributed in Xizang is much higher than
those endemic to Xizang itself, but there exist newly arisen species and infraspecific
forms or varieties which show that the speciation is apparently still active in Xizang.
The rosaceous flora of Xizang is a combination of old and new floristic elements, based
on the old floristic components, affected by the upheaval of the Himalayas, the differen-
tiation and speciation have been taking place in the long history.
The geographical distribution of Rosaceae in Xizang may be divided into 5 regions,
i.e. the northeastern, southeastern, southern, northwestern and northern. The rosaceous
plants are most abundant in the southeastern area, next in southern area, fewer in the
northeastern and very rare in the northwestern and northern regions. The general ten-
dency of the distribution of Rosaceae in Xizang is that the number of species gradually
decreases from the southeast to the northwest and the habit gradually changes from
trees, shrubs and herbaceous plants in the southeast to cushion-like scrubs and dwarf
perennial herbs in the northwest. These facts clearly show that the uplift of the Hi-
malayas has deeply affected the phytogeographical distribution of Xizang Rosaceae.
The rosaceous flora of Xizang has close relationships with those of the adjoring
regions, i.e. Yunnan and Sichuan. Besides, it is connected with floras of Nepal, Sikkim,
Bhutan nothern Buram and nothern India, but silghtly influenced by the Ancient Medi-
terranean flora. 相似文献
60.
通过野外调查,对连云港白塔埠机场周边的种子植物区系进行了分析。结果表明:该区共有主要种子植物73科、190属、261种,其中裸子植物4科、5属、6种;双子叶植物56科、154属、216种;单子叶植物13科、31属3、9种。科的区系可划分8个类型和4个变型,以世界分布、泛热带分布和北温带分布为主;属的分布类型可划分为14种类型和9个变型,温带分布占总属数的46%;在种一级的分布中,世界分布种占总种数约71%,泛热带分布和温带分布各占13%,而热带亚洲至热带美洲、旧世界热带分布仅占1.2%,反映出由暖温带向亚热带过渡的特点。 相似文献