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排序方式: 共有540条查询结果,搜索用时 46 毫秒
501.
Ashwini Kumar H. S. Batra Mithu Banerjee S. Bandyopadhyay T. K. Saha Pratibha Misra Vivek Ambade 《Indian journal of clinical biochemistry : IJCB》2017,32(3):343-346
Thalassemia is a congenital hemolytic disease which is treated by repeated blood transfusion. Chronic iron overload is currently considered to be the primary cause of mortality in β-thalassemia, mainly due to the induction of left-sided cardiac failure. Iron overload results from a number of mechanisms associated with the disease itself. In addition to chronic iron overload thalassemic patients are more prone for procoagulant status which in turn lead to clinical thrombotic events. The hypercoagulable state in thalassemia is due to multiple elements, a combination of which is often the drive behind a clinical thromboembolic events. PAI-1 study was done in thalassemia major patients receiving multiple blood transfusion as a marker for procoagulant status. Total of 30 thalassemic patients on repeated blood transfusion was included in the study and total of 30 healthy age and sex matched controls were included in the study. It was also found that there was significant differences between cases and controls. The mean level of PAI 1 in controls was 3047 ± 414 pg/ml, the value in cases was 3683 ± 358 pg/ml. The level was significantly increased (p < 0.05) in the cases compared to controls. PAI-1 levels were also compared with the total number of blood transfusion which correlates well. 相似文献
502.
503.
R. Senthil Kumar T. N. Pattabiraman 《Indian journal of clinical biochemistry : IJCB》1996,11(2):152-157
A chymotrypsin-like enzyme was purified from rat plasma, involving ammonium sulfate fractionation and chromatographgy on CM-sephadex and red sepharose. The purified enzyme effectively hydrolysed the ester substrates for chymotrypsin (N-acetyl L-tyrosine ethyl ester and N-acetyl L-tryptophan ethyl ester). The Km values for the two substrates were 2.2×10?3M and 9.0×10?3M respectively. The hydrolytic activity of the enzyme was inhibited by phenylmethyl sulfonyl fluoride and tosylphenylalanine chloromethylketone, suggesting the presence of serine and histidine at the active centre. The enzyme exhibited anionic nature and possessed a high molecular weight (MW 71,000) as observed by gel exclusion chromatography on Sephadex G-200. The enzyme was stable upon exposure to pH 7.0–9.0, but was inactivated upon heat treatment at 60°C for 5 min. 相似文献
504.
Medically diagnosed alcoholics can be differentiated reliably from non-alcoholics using clinically laboratory tests. In the
present study, patients with liver diseases either due to alcohol or without alcohol compared with a group of normal healthy
persons. Heavy drinkers showed significantly lower body weight and percent body fat, and low BMI compared with other groups.
The percentage of hemoglobin and total number of RBC were found to be significantly decreased, whereas mean corpuscular volume
(MCV) significantly increased in alcoholic liver disease (ALD). Hyperbilirubinemia, hyperuricemia and hypoalbuminemia correlate
with alcohol intake. Albumin/globulin ratio significantly decreased in ALD. In acute liver injury AST/ALT ratio is ≤1.0, whereas
in alcoholic hepatitis it is always >1.0. Moderately elevated level of ALP and high GGT values are good discriminator of alcoholic
patients. Alcohol-induced liver injury is linked to oxidative stress as observed by decreased level of reduced glutathione
and ascorbic acid, and increased level of thiobarbituric acid reactive substances. 相似文献
505.
Starting with an elementary problem that appeared in the Putnam mathematics competition, we proceed to discuss some techniques of transcendental number theory and prove the following result. If p, q, r are distinct primes and if c is a real number with the property that pc, qc, rc are integers, then c must be a non-negative integer. The tools used are some linear algebra and complex analysis. The zero-density estimate method discussed here was used by Alan Baker to prove his celebrated theorem on linear forms in logarithms. The question as to whether we can replace three primes by two primes is an open question. 相似文献
506.
Almerie MQ Matar HE Jones V Kumar A Wright J Wlostowska E Adams CE 《Health information and libraries journal》2007,24(4):283-286
Background: The Polish Medical Bibliography (Polska Bibliografia Lekarska) contains 350 000 records dating from 1979. These records from the fields of medicine, nursing, dentistry, health care systems and preclinical sciences are from nearly 300 biomedical journals published in Poland. Methods: We systematically searched the Polish Medical Bibliography Part II (1996–2006) CD‐ROM (July 2006) using both English and Polish phrases for randomized trials, manually checked results and, for the trials identified in this way, sought these on medline and embase . Results: Systematic searching identified records of 680 randomized trials from all areas of health care. Nearly 40% of these were not found on either medline or embase . Conclusions: The Polish Medical Bibliography should be of interest to health care information specialists concerned with comprehensive searches for trials. 相似文献
507.
Ratan Kumar D. P. Chattopadhyay Radhey Shyam 《Indian journal of clinical biochemistry : IJCB》1993,8(1):20-25
Intraperitoneal administration of glucose (20%), Sucrose (20%) and mannitol (15%) to the rats, at a dose of 5ml/100g body weight 3 hrs. prior to hypoxic exposure (simulated high altitude 10,973m, 32°C) significantly increased the hypoxic tolerance. Intraperitoneal administration of these solutions resulted in accumulation of transudate fluid in the peritoneal cavity. A decrease in the excretion of urine, increase in hematocrit value, haemoglobin level, blood viscosity and serum protein were observed. Moisture content of lungs amongst other tissue was found to be decreased. Results are suggestive that dialysis across the peritoneal membrane might have removed some material from the blood in the peritoneal fluid which might have been responsible for the increased hypoxic tolerance. 相似文献
508.
Satya Vati Rana Raj Kumar Singhal Kartar Singh Lata Kumar 《Indian journal of clinical biochemistry : IJCB》2004,19(2):5-9
Adenosine deaminase activity (ADA) was estimated in cerebrospinal fluid (CSF) of 30 patients of tuberculous meningitis (TBM)
and 10 patients each of partially treated pyomeningitis (PTM), aseptic meningitis (AM) and pyogenic meningitis (PM). Mean
ADA levels in CSF of TBM patients were higher (18.22 U/L) as compared to 6.28 U/L, 3.43 U/L and 7.98 U/L in PTM, AM and PM
respectively. This difference of ADA values in CSF between TBM and other types of meningitis was statistically significant
(p<0.01) different. Sensitivity and specificity of ADA levels in CSF of children to diagnose tuberculous meningitis was 66.6%
and 90% respectively at 10 U/L cut off of ADA levels in CSF. ADA levels in CSF could also differentiate PTM, AM and PM from
TBM with a specificity of 90%, 100% and 80% respectively. 相似文献
509.
P. K. Nigam V. S. Narain Ajay Kumar 《Indian journal of clinical biochemistry : IJCB》2006,21(1):54-61
Sialic acid, the acylated derivatives of 9-carbon sugar neuraminic acid, present as terminal component of oligosaccharide
chains of many glycoproteins and glycolipids, has been recognized to be involved in the regulation of a great variety of biological
phenomena. Studies have shown that serum sialic acid predicts both coronary heart disease and stroke mortality and reflects
the existence or activity of an atherosclerotic process. Most of the studies have shown an elevation in serum sialic acid
concentration in coronary heart disease and a positive correlation between the raised serum sialic acid and the severity of
the coronary lesions is observed. However, a few contradictory reports are also available. Racial differences in serum sialic
acid have also been reported and correlated with international differences in the prevalence of atherosclerosis. Reduced sialic
acid content of platelets, erythrocytes and lipoproteins may play important role in the pathogenesis of atherosclerosis. Elucidation
of the mechanism of alternation in sialic acid concentration may throw more light on its potential clinical utility. Hence
more studies are needed to designates sialic acid as a cardiovascular risk factor/marker. 相似文献
510.
Praveen Kumar Shetty T. N. Pattabiraman 《Indian journal of clinical biochemistry : IJCB》2004,19(1):97-101
The present study deals with the estimation of total carbohydrate, protein bound carbohydrate, bound fucose and sialic acid
along with total protein in disease conditions like gingivitis, periodontitis and their comparison with the normals.
The neutral hexose values in gingivitis (8.08±2.20mg/100mg protein) and periodontitis (12.5±2.16mg/ 100mg protein) decreased
significantly when expressed per 100 mg protein compared to normals (19.8±1.89mg/100mg protein). This might be because of
higher protein concentration in these two clinical conditions. The ethanol insoluble hexose values were significantly reduced
in both these conditions compared to controls (3.71±1.64,5.91±1.63,7.65±0.86mg/100mg protein respectively). The ethanol soluble
hexose values were also found to be drastically reduced. This decrease in saliva appears to be characteristic feature of oral
diseases. In gingivitis and periodontitis fucose level was found to be increased compared to normals when expressed as a function
of salivary volume. However in terms of protein concentration the values in gingivitis (2.95±1.59), periodontitis (3.26±0.98)
and normals (3.20±0.50mg/100mg) were not different. Sialic acid in ethanol insoluble fraction of salivary samples mg/100mg
protein was found to be significantly reduced in both gingivitis (0.78±0.33) and periodontitis (0.95±0.31) compared to controls
(1.92±0.33) 相似文献