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51.
The mycotoxins citrinin, patulin and terreic acid are absorbed by rice seedling roots and translocated to shoots. Ten day analysis of toxin treated plants showed persistence of citrinin, patulin and terreic acid. All three toxins at a concentration of 100 ppm showed phytotoxic activity indicating terreic acid in addition to citrinin and patulin as phytotoxins.  相似文献   
52.
Ultraviolet-B (UV-B) irradiation in the range of 280-320nm has shown to be a promising immunomodulatory tool in xenogenic hepatocyte transplantation. Most of the studies documenting the effect(s) of UV-B irradiation on hepatic transplantation have been carried out in small model systems with very little information available in larger animals. The aim of the present investigation was to study in vitro the effect(s) of UV-B irradiation (302 nm) at 0, 250, 500, 1250 and 2500 J/m2 on the viability and cellular responses in the isolated goat hepatocytes. The results showed that the cells irradiated at 0, 250, 500, 1250 and 2500 J/m2 demonstrated a viability of 90-95%. However, intracellular [Ca2+]i influx as quantitated by Flu 3-acetete showed a significant increase with irradiation as observed in confocal microscope. The intracellular pH (quantitated by the flourescence of BCCEF) although tend to show an increase with UV-B irradiation was not statistically significant. The present observations suggest that there is a modulation in the intracellular [Ca2+]i concentration within the hepatocytes at higher dose of UV-B irradiation without altering the viability of hepatocytes. These observations are significant for the xenotransplantation of cells.  相似文献   
53.
Airway surface liquid (ASL) lines the conducting airways of the respiratory tract. We collected small samples of this liquid from the lower tracheae of anesthetized C57BL/6 mice and determined its ionic composition (in mM: 87.2 Na(+), 4.7 K(+), and 57.0 Cl(-)). Intravenous methacholine produced significant increases in the concentrations of Na(+), K(+), and Cl(-) within ASL. A limited analysis of liquid from cystic fibrosis transmembrane conductance regulator (CFTR) knockout mice revealed no significant differences compared with littermate controls; however, Pseudomonas aeruginosa infection led to an increase in the salt concentration of ASL in cftr(+/+) mice. Morphometric measurements of tracheal submucosal gland volume revealed significant differences between inbred mouse strains, corresponding to ease of ASL collection. We conclude that although submucosal glands may be responsible for the production of some ASL, the ionic composition of this liquid is actively regulated by the underlying epithelial cells.  相似文献   
54.
Phenotypic identification of groupers of the genus Epinephelus is based on color patterns and a suite of morphologic characters. However, these characters often show intraspecific variations and differences between juveniles and adults of the same species. The present work is an attempt to study and ratify the status of Epinephelus spp. using random amplified polymorphic DNA (RAPD) analysis based on samples drawn from southeast and southwest coasts of India. The RAPD fingerprints generated in Epinephelus diacanthus, E. areolatus, E. chlorostigma, E. bleekeri, E. coioides, E. tauvina, and E. malabaricus with 4 primers (OPA 01, OPA 07, OPF 08, and OPF 10) were consistent, reproducible, and yielded species-specific diagnostic markers in all the species. A total of 59 RAPD loci in the size range of 70 to 4500 bp were produced from all 4 arbitrary primers. An unweighted pair-group method with arithmetic mean (UPGMA) dendogram was constructed based on genetic distance values to show the genetic relationships among the 7 species. All the individuals of each species formed monophyletic species clusters. The mean intraspecies genetic distance value (0.305) was significantly lower than the interspecies value (0.365). Epinephelus malabaricus was most distantly related to E. diacanthus and E. bleekeri. The genetic relationship was very close among E. coioides, E. tauvina, and E. malabaricus and also between E. chlorostigma and E. bleekeri. Within-species genetic polymorphism was highest in E. chlorostigma (49.15%) and lowest in E. tauvina (25.42%).  相似文献   
55.
Angiogenin is a protein belonging to the superfamily of RNase A. The RNase activity of this protein is essential for its angiogenic activity. Although members of the RNase A family carry out RNase activity, they differ markedly in their strength and specificity. In this paper, we address the problem of higher specificity of angiogenin towards cytosine against uracil in the first base binding position. We have carried out extensive nano-second level molecular dynamics(MD) computer simulations on the native bovine angiogenin and on the CMP and UMP complexes of this protein in aqueous medium with explicit molecular solvent. The structures thus generated were subjected to a rigorous free energy component analysis to arrive at a plausible molecular thermodynamic explanation for the substrate specificity of angiogenin.  相似文献   
56.
An SAR study of an HTS screening hit generated a series of pyridodiazepine amines as potent inhibitors of Helicobacter pylori glutamate racemase (MurI) showing highly selective anti-H. pylori activity, marked improved solubility, and reduced plasma protein binding. X-ray co-crystal E–I structures were obtained. These uncompetitive inhibitors bind at the MurI dimer interface.  相似文献   
57.
Cellular rhythms regulate various physiological functions in circadian oscillatory mechanisms. Weight cycling or ‘yo-yo’ dieting is an evitable process in human, because of subsequent loss and regain of body weight due to irregular diet. Human weight cycle (HWC) is the major factor for causing global epidemic diseases in human beings. Understanding the HWC process would provide potent additional knowledge to prevent obesity. However till date, there is no study dealing with examine the HWC model using virtual cell simulation based on system biological approach. Therefore, the present study was designed to develop a computational HWC model, which was simulated using E-cell system v3.0. The developed model has the cyclic feedback reactions of three significant variables (the consecutive cycles of weight loss in continuous food intake (Q) and regain of body weight (P) at highest threshold point of cognitive restraint (R)) which are obtained by mathematical modelling. The dynamic plot results supported that the PQR variables depicted sustained oscillation with reversible modification due to protein diet. By contrast, the virtual model simulation would provide extensive information on HWC, which might provide knowledge to develop HWC linked with obesity pathway. The presents study concludes that optimization of body weight is essential to prevent the obesity based diseases.  相似文献   
58.
Mycotoxins are natural, secondary metabolites produced by fungi on agricultural commodities in the field and during storage under a wide range of climatic conditions. The ochratoxin A (OTA) is a nephrotoxic mycotoxin produced by several species of Aspergillus and Penicillium. In this study, the influence of carbon and nitrogen sources on ochratoxigenic Penicillium species was assessed. The ochratoxigenic Penicillium species were isolated from poultry feed samples of Andhra Pradesh, India. The isolated ochratoxigenic Penicillium species were identified, screened and characterised as OTA producers by high performance thin layer chromatography (HPTLC) and confirmed by high performance liquid chromatography (HPLC). This experiment was carried out using Czapak yeast Autolysate (CYA) medium with different carbon (C) and nitrogen (N) sources at pH 6.5 and incubated at 25 ± 2°C under dark condition. Maximum OTA production was recorded in the presence of D-glucose followed by D-galactose and D-lactose as carbon sources. Similarly, the maximum amount of OTA production was observed in thiourea followed by potassium nitrate as nitrogen source. However, OTA production, final pH of the medium, and mycelial yield and OTA production of both the species of Penicillium varied with C and N present in the medium. The kinetics of the both species of Penicillium was observed for 30 days at an interval of three days. The maximum amount of OTA was detected by 12 and 15 days incubation periods for Penicillium nordicum and Penicillium verrucosum, respectively.  相似文献   
59.
The preorbital gland is a specialized dermal gland of antelopes which plays an important role in territorial marking behavior and pheromonal communication. To our knowledge, there is little information available on the role of preorbital gland marks in Indian antelopes (blackbucks). Males are seen averting the gland during behavioural display and territorial marking but the functional aspect of this gland has not been examined. Hence, the aim of this study was to describe the histomorphology of the preorbital gland in territorial and non-territorial male blackbucks to determine its morphology and secretory function. The results showed that the preorbital gland is composed of modified sebaceous and apocrine glands. The apocrine gland is lined by simple cuboidal epithelial cells; the serous parts of the secretory products are often seen in the apical portions of the cells. The myoepithelial cells contain actin filaments lying on the basal membranes of the apocrine gland. There are some considerable histological changes in the presence of the sebaceous and apocrine glands in territorial males in comparison to non-territorial males. The following histological changes associated with occurrence of the sebaceous and apocrine glands have been observed in territorial and non-territorial male blackbucks: (1) increase of size of sebaceous and apocrine glands and (2) increase in density of sebaceous and apocrine glands in territorial males compared to non-territorial males. It is suggested that the higher development (i.e., size) and density of sebaceous and apocrine glands in territorial males could depend on hormone production (i.e., testosterone). Based on the histological observation and the role of sebaceous and apocrine glands in the preorbital gland supported by literature, it is possible to conclude that both territorial and non-territorial blackbuck males may produce pheromonal substances through preorbital gland (secretion) for olfactory communication.  相似文献   
60.
Mice deficient for the fibulin-5 gene (Fbln5−/−) develop pelvic organ prolapse (POP) due to compromised elastic fibers and upregulation of matrix metalloprotease (MMP)-9. Here, we used casein zymography, inhibitor profiling, affinity pull-down, and mass spectrometry to discover additional protease upregulated in the vaginal wall of Fbln5−/− mice, herein named V1 (25 kDa). V1 was a serine protease with trypsin-like activity similar to protease, serine (PRSS) 3, a major extrapancreatic trypsinogen, was optimum at pH 8.0, and predominantly detected in estrogenized vaginal epithelium of Fbln5−/− mice. PRSS3 was (a) localized in epithelial secretions, (b) detected in media of vaginal organ culture from both Fbln5−/− and wild type mice, and (c) cleaved fibulin-5 in vitro. Expression of two serine protease inhibitors [Serpina1a (α1-antitrypsin) and Elafin] was dysregulated in Fbln5−/− epithelium. Finally, we confirmed that PRSS3 was expressed in human vaginal epithelium and that SERPINA1 and Elafin were downregulated in vaginal tissues from women with POP. These data collectively suggest that the balance between proteases and their inhibitors contributes to support of the pelvic organs in humans and mice.  相似文献   
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