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31.
By means of steam distillation, adsorption chromatography and GC/MS analysis, seven sulphur components (di-, tri- and tetra-sulphides) have been characterised in addition to those previously reported from Ferula asafoetida of Afghan origin. The identity of some of the components has been confirmed by synthesis and comparison of GC retentions. The quantitative composition of the constituents in the volatile oil has also been determined.  相似文献   
32.
Dermatoglyphic traits have been used to assess population affinities and structure. Here, we describe the digital patterns of four Eskimo populations from Alaska: two Yupik-speaking villages from St. Lawrence Island and two Inupik groups presently residing on mainland Alaska. For a broader evolutionary perspective, these four Eskimo populations are compared to other Inuit groups, to North American Indian populations, and to Siberian aggregates. The genetic structures of 18 New and Old World populations were explored using R-matrix plots and Wright's FST values. The relationships between dermatoglyphic, blood genetic, geographic, and linguistic distances were assessed by comparing matrices through Mantel correlations and through partial and multiple correlations. Statistically significant relationships between dermatoglyphics and genetics, genetics and geography, and geography and language were revealed. In addition, significant correlations between dermatoglyphics and geography, with linguistic variation constant, were noted for females but not for males. These results attest to the usefulness of dermatoglyphics in resolving various evolutionary questions concerning normal human variation.  相似文献   
33.
The ability of deglycosylated hCG (dghCG) prepared by deglycosylation of a clinical hCG (3000 IU/mg) preparation, to block luteal function during regular cycles as well as luteal rescue in simulated and mated cycles of female bonnet monkeys (M. radiata) has been evaluated. The cycle length (C:28 vs E:24 days) and the total progesterone produced during the luteal phase was significantly reduced (by 45%, P < .05) by injecting 450 micrograms of dghCG/day (in split doses) on days 18, 19, and 20 of cycle. At the doses tested the dghCG used did not exhibit any agonistic activity in the female monkey. In a second experiment injection of 200 micrograms of dghCG/day on days 18-20 of cycle blocked the normal response of the luteal tissue to exogenous hCG (10 micrograms of a 12,000 IU/mg preparation) injected on day 23 of cycle. In a third experiment no pregnancies occurred when a group of 5 animals were injected dghCG (450 micrograms dghCG/day) on days 18-21 of their mated cycle. Animals chosen for this study were proven fertile regularly cycling monkeys and these were cohabited with males between days 9 and 14 of cycle. Each of the monkeys was exposed to 3 consecutive treatment cycles. During post-treatment phase 2 out of 3 monkeys exposed to males became pregnant. The study clearly demonstrates that it is possible to block normal luteal function as well as luteal rescue of the female monkey by using dghCG in the right dose and mode.  相似文献   
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Fusarium isolates from specific diseased sorghum plants and rain-soaked wheat and wheat flour associated with human mycotoxicosis in India have been screened for their toxigenic potential. Of the 322 isolates screened, 11 isolates were found to produce deoxynivalenol in concentrations ranging from 0.01 to 186 micrograms g-1. The occurrence of deoxynivalenol-producing fusaria in a nontemperate region and deoxynivalenol production in low concentrations by Fusarium moniliforme are reported for the first time.  相似文献   
36.
The suitability of micro-Kjeldahl, biuret and Folin-Ciocalteu methods of protein determination in analysing the haemolymph protein concentration of Scylla serrata was assessed. It was found that biuret method is simple, reliable and the results are consistent. Intra-individual factor as a function of time of day is also responsible for individual variability in the haemolymph protein concentration of the crab.  相似文献   
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Chlamydophila pneumoniae, the causative agent of chronic obstructive pulmonary disease (COPD), is presently the fifth mortality causing chronic disease in the world. The understanding of disease and treatment options are limited represents a severe concern and a need for better therapeutics. With the advancements in the field of complete genome sequencing and computational approaches development have lead to metabolic pathway analysis and protein-protein interaction network which provides vital evidence to the protein function and has been appropriate to the fields such as systems biology and drug discovery. Protein interaction network analysis allows us to predict the most potential drug targets among large number of the non-homologous proteins involved in the unique metabolic pathway. A computational comparative metabolic pathway analysis of the host H. sapiens and the pathogen C pneumoniae AR39 has been carried out at three level analyses. Firstly, metabolic pathway analysis was performed to identify unique metabolic pathways and non-homologous proteins were identified. Secondly, essentiality of the proteins was checked, where these proteins contribute to the growth and survival of the organism. Finally these proteins were further subjected to predict protein interaction networks. Among the total 65 pathways in the C pneumoniae AR39 genome 10 were identified as the unique metabolic pathways which were not found in the human host, 32 enzymes were predicted as essential and these proteins were considered for protein interaction analysis, later using various criteria''s we have narrowed down to prioritize ribonucleotide-diphosphate reductase subunit beta as a potential drug target which facilitate for the successful entry into drug designing.  相似文献   
39.
CD44 is a multifunctional cell receptor that conveys a cancer phenotype, regulates macrophage inflammatory gene expression and vascular gene activation in proatherogenic environments, and is also a marker of many cancer stem cells. CD44 undergoes sequential proteolytic cleavages that produce an intracytoplasmic domain called CD44-ICD. However, the role of CD44-ICD in cell function is unknown. We take a major step toward the elucidation of the CD44-ICD function by using a CD44-ICD-specific antibody, a modification of a ChIP assay to detect small molecules, and extensive computational analysis. We show that CD44-ICD translocates into the nucleus, where it then binds to a novel DNA consensus sequence in the promoter region of the MMP-9 gene to regulate its expression. We also show that the expression of many other genes that contain this novel response element in their promoters is up- or down-regulated by CD44-ICD. Furthermore, hypoxia-inducible factor-1α (Hif1α)-responsive genes also have the CD44-ICD consensus sequence and respond to CD44-ICD induction under normoxic conditions and therefore independent of Hif1α expression. Additionally, CD44-ICD early responsive genes encode for critical enzymes in the glycolytic pathway, revealing how CD44 could be a gatekeeper of the Warburg effect (aerobic glycolysis) in cancer cells and possibly cancer stem cells. The link of CD44 to metabolism is novel and opens a new area of research not previously considered, particularly in the study of obesity and cancer. In summary, our results finally give a function to the CD44-ICD and will accelerate the study of the regulation of many CD44-dependent genes.  相似文献   
40.
Nasi R  Pinto BM 《Carbohydrate research》2006,341(14):2305-2311
The synthesis of new analogues of the naturally occurring glycosidase inhibitor, salacinol, and its ammonium analogue, ghavamiol is described. These analogues contain an additional hydroxymethyl group at C-1, which was intended to form additional polar contacts within the active site of glycosidase enzymes. The target zwitterionic compounds were synthesized by means of nucleophilic attack at the least hindered carbon atom of 2,4-O-benzylidene-l (or d)-erythritol 1,3-cyclic sulfate by 2,5-anhydro-1,3:4,6-di-O-benzylidene-2,5-dideoxy-5-thio (or 1,5-imino)-l-iditol.  相似文献   
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