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1.
Effects of localized low (2.5 Gy) and high (10 Gy) levels of gamma irradiation on the testis of albino rats were studied. A marked increase in the testicular total lipid, phospholipid and cholesterol content was observed at all post-treatment intervals except at 16 weeks where the contents decreased. A significant decrease in the activity of acid phosphatase/g of testis was seen at both the doses, the minimum value being at 4 weeks. The decrease in acid phosphatase activity is correlated with the state of germ cell population in seminiferous tubule which is found to be depleted at 4 week interval. The alkaline phosphatase activity/g testis however, showed a significant increase, the maximum being at 4 weeks post-treatment. Thereafter, the values of the enzyme activity showed a slight recovery at 16 weeks post-irradiation. ATPase activity increased initially followed by a significant decrease at all post-treatment intervals.  相似文献   
2.
Prey selection and the feeding habits of tiger Panthera tigris, leopard Panthera pardus and Asiatic wild dog Cuon alpinus were investigated from June 2009 to December 2011 in Pakke Tiger Reserve, Arunachal Pradesh. A total of 422 scats were analyzed of which, 109 scats were of tigers, 150 were of leopard and 163 scats were of dholes. Multinomial Likelihood ratio test was used to estimate the prey selectivity of predators and Ivlev index, Pianka index were used to estimate prey preference and overlap respectively. Biomass consumption for three sympatric predators varied from 254.3 kg for dholes to 599.1 kg for tigers. Sambar, barking deer, wild pig were preyed more than their availability by all the predators. Ivlev index shows barking deer and sambar were preferred more than available prey for tiger where as leopard preferred sambar more than available and avoided barking deer. Dhole preferred more than available wild pig and barking deer. There was a high overlap between tiger–leopard (85.3%) and tiger–dhole (77.5%). To the best of our understanding, this study provides the first reliable information on prey selection and food habits of sympatric large carnivores in a protected area of Eastern Himalayan tropical rainforest.  相似文献   
3.
Abstract

This study deals with the open pond (OP) pilot scale treatment of cassava effluent and enhancement of Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) enzyme through CO2 utilization by the microalga, Acutodesmus obliquus RDS01. The cassava effluent treatment (ET) revealed maximum reduction of ammonia (96.8%), calcium (94.6%), chloride (95.2%), chlorine (98.5%), inorganic phosphate (94.6%), magnesium (96.8%), nitrate (96.89%), organic carbon (95.9%), organic phosphorus (96.3%), potassium (97.9%), sodium (97.1%), and sulfate (95.4%) on 15th day using A. obliquus. The microalga produced highest RuBisCO enzyme activity (90%), CO2 utilization efficiency (95%), biomass (8.9 gL?1), lipid (176.65?mg mL?1), carbohydrate (96.78?mg mL?1), biodiesel (4.1?mL g?1), and bioethanol (3.7?mL g?1) during OP treatment. The isolated RuBisCO gene (rbcL) was used to construct the protein model by homology modeling. The microalgal-lipid content was analyzed through thin layer chromatography, the biodiesel produced was analyzed using Fourier-transform infrared spectroscopy and gas chromatography mass spectrometry (GCMS). The bioethanol production was confirmed by high performance liquid chromatography and GCMS analyses. A. obliquus produced of 98.75% biodiesel and 96.83% bioethanol in the OP pilot scale treatment A. obliquus. Overall, the microalga A. obliquus could act as an effective CO2 capturing and bioremediation agent in the cassava ET, and also for the biodiesel and bioethanol can be produced.  相似文献   
4.

Objective

This study aimed to generate age‐ and sex‐specific percentiles for body composition indices in children and to assess the variability in these indices, in relation to BMI.

Methods

Anthropometry and body fat were measured with the BOD POD (Cosmed; Rome, Italy) in 9,702 children from Bangalore, India. Smoothed percentile curves using the lambda‐mu‐sigma method were obtained for BMI, fat‐free mass index (FFMI), fat mass index (FMI), and body fat percentage (% BF).

Results

Percentile curves for % BF and FMI in boys increased from 6 to 12 years and declined from 13 years on, while in girls, it increased until 15 years. The FFMI percentile curves increased with age in both sexes. The mean FMI declined from 12 years on in boys, corresponding to a large increase in FFMI from that age, while in girls, both FMI and FFMI continued to increase. The 75th percentile of % BF and FMI had greater sensitivity to identify children with obesity.

Conclusions

This study developed smoothed percentile curves for body composition in Indian children and suggests FMI and FFMI as good indicators of growth in children.
  相似文献   
5.
This review describes the MOLS method and its applications. This computational method has been developed in our laboratory primarily to explore the conformational space of small peptides and identify features of interest, particularly the minima, i.e., the low energy conformations. A systematic “brute-force” search through the vast conformational space for such features faces the insurmountable problem of combinatorial explosion, whilst other techniques, e.g., Monte Carlo searches, are somewhat limited in their region of exploration and may be considered inexhaustive. The MOLS method, on the other hand, uses a sampling technique commonly employed in experimental design theory to identify a small sample of the conformational space that nevertheless retains information about the entire space. The information is extracted using a technique that is a variant of the self-consistent mean field technique, which has been used to identify, for example, the optimal set of side-chain conformations in a protein. Applications of the MOLS method to understand peptide structure, predict the structures of loops in proteins, predict three-dimensional structures of small proteins, and arrive at the best conformation, orientation, and positions of a small molecule ligand in a protein receptor site have all yielded satisfactory results.  相似文献   
6.
Prior development of a unique androgen-receptor (AR)-negative cell line (HH870) from organ-confined (T2b) human prostate cancer (CaP) enabled comparison of the gangliosides associated with normal and neoplastic prostate epithelial cells, organ-confined versus metastatic (DU 145, PC-3), and AR-negative versus AR-positive CaP cell lines. Resorcinol-HCl and specific monoclonal antibodies were used to characterize gangliosides on 2D-chromatograms, and to visualize them on the cell surface with confocal-fluorescence microscopy. AR-negative cells expressed GM1b, GM2, GD2, GD1a, and GM3. GM1a, GD1b, and GT1b were undetectable. GM1b and GD1a were more prominent in AR-negative than in AR-positive cells. PC-3 and HH870 cells were unique in the expression of O-acetylGD2 (O-AcGD2) and two alpha2,3-sialidase-resistant, alkali-susceptible GMR17-reactive gangliosides. Expression of GD1a, GM1b, doublets of GD3, GD2, and O-AcGD2, and the presence of an additional alkali-labile-14.G2a-reactive ganglioside, two alkali-susceptible, and three alkali-resistant GMR17-reactive gangliosides makes HH870 a potential component of a polyvalent-vaccine for active-specific immunotherapy of CaP.  相似文献   
7.
The benzimidazole derivative Schiff bases and their copper(II) (Cu(II)) mixed-polypyridyl complexes (1-4) have been synthesized and characterized by the spectral and analytical techniques. DNA binding/cleavage studies indicate a stronger binding capability for the complex 4 which is confirmed by the absorbance, viscometric and gel-electrophoresis studies. The photocleavage of plasmid pBR322 DNA reveals that hydroxyl radical (OH(?)) and singlet oxygen ((1)O(2)) are likely to be the reactive species. Analysis of the growth activity shows that the antimicrobial effect of these Schiff bases on Gram-negative bacteria is higher than that on Gram-positive. Furthermore, the complexes having nitro group show an increased antimicrobial effect.  相似文献   
8.
9.
Selvan AT  Sankaran K 《Biochimie》2008,90(11-12):1647-1655
Lipid modification of proteins is an essential post-translational event that can be targeted for protein engineering and pharmaceutical applications. In this regard, the unique and ubiquitous bacterial N-terminal lipid modification (N-acyl S-diacylglyceryl modification of N-terminal cysteine) is particularly attractive. It is initiated by phosphatidylglycerol:prolipoprotein diacylglyceryl transferase (Lgt) and therefore its properties, which remain uninvestigated, largely define the specifics of the modification. A synthetic peptide-substrate (MKATKSAVGSTLAGCSSHHHHHH) with a short hydrophilic h-region, unlike that of the prototypical substrate used so far, demonstrated lack of enzyme's substrate preference based on hydrophobicity, perhaps accounting for a significant number of lipoproteins possessing hydrophilic signal peptides. Solubilization experiments revealed a peripheral and possibly reversible hydrophobic association of Lgt with the inner-membrane on the cytosolic side contradicting its deduced transmembrane topology. Except for heat stability, the soluble enzyme was indistinguishable from the membrane-bound enzyme in kinetic behaviour, indicating that the committed first step of bacterial lipid modification may be aqueous compatible. The direct, more accurate, precise and easier paper electrophoretic assay, designed anew, and Lgt's ready extraction with water or low ionic strength solutions from inverted vesicles could aid better understanding and exploitation of the enzyme and bacterial lipid modification.  相似文献   
10.
An investigation on the influence of lead toxicity on some of the hepatic enzymes was studied in rats both after a shorter interval of 15 d and after longer intervals of 60 and 90 d. Three different doses of lead as 5, 10, and 50 mg/kg body wt were administered orally on every alternate day. Whereas significant inhibition of succinic dehydrogenase was seen following lead poisoning, the activity acid and alkaline phosphatase increased with lead intoxication. The histoarchitecture of the liver was grossly intact. Liver accumulated less lead compared to kidney at 60 and 90 d.  相似文献   
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