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91.
Photoreactivation (PR) after 365-nm inactivation was measured in four strains of Escherichia coli differing in repair capability. Photoreactivation was observed in the recA strains K12 and AB2480 and K12 AB2463 indicating a significant role of pyrimide dimers in the lethal action of 365-nm radiation in these strains. Significant PR was not observed in the uvrA strain, K12 AB1886, or in the repair proficient strain, K12 AB1157, after 265-nm inactivation. Biological evidence indicated that stationary phase cells had not lost the capacity for photo-enzymatic repair after fluences of 365-nm radiation of 2 × 106 J/m−2 or less. It is proposed that pyrimidine dimers, although induced, are not significant 365-nm lethal lesions in uvrA and wild-type strains because of their efficient dark repair.  相似文献   
92.
HLA typing was performed on 232 rubella seronegative (HAI antibody titer <8) children immunized with RA 27/3 vaccine. High convalescentphase geometric mean antibody titers were noted in children one to five years of age, in girls one to 12 years of age, in subjects with AB blood type and in vaccinees with HLA types B14 and BW22. Of nine children with rubella titers512, 44 percent had HLA type A28; in contrast, only eight percent of the total group had A28 HLA type. HLA-A2 was present in four, and HLA types B12 and BW17 were present in three of the six children in whom seroconversion did not occur. Fifteen of 37 sibling pairs had identical antibody responses; in contrast, only 18 percent of randomly paired children had titers identical to each other. Vaccine-related symptomatology could not be associated with any HLA type. The results of this study suggest that infection with and antibody response to RA 27/3 rubella vaccine is influenced by genetic factors, which include cellular membrane determinants.  相似文献   
93.
94.
A series of derivatives of the new ring system thiopyrano[2,3-e]indol-2-one was prepared with the aim of obtaining new photochemotherapeutic drugs. Biological screenings were performed on this new class of photoactivable drugs and a strong antiproliferative effect was observed upon irradiation with UVA light. The compound bearing a methyl substituent at the pyrrole nitrogen resulted as the most interesting showing IC50 in the nanomolar range.  相似文献   
95.
Monoacylglycerol lipase (MAGL) has an essential role in the catabolic pathway of the endocannabinoid 2-arachidonoylglycerol, which makes it a potential target for highly specific inhibitors for the treatment of a number of diseases. We designed and synthesized a series of carbamate analogues of URB602. We evaluated their inhibitory activity toward human MAGL in vitro both in cell culture and lysates. The target compounds exhibited moderate to excellent inhibitory activity against MAGL. The most promising compound 2b showed good inhibitory activity with IC50 value of 4.5?±?0.70?μM reducing MAGL activity to 82% of controls at 10?μM compared to 66% for the parent compound URB602. Interestingly, compounds 2b and 2c induce cell death through the inhibition of MAGL. Molecular modelling approaches and docking studies, used to investigate inhibitory profiles, indicated that trifluoromethyl substitutions of the aryl group and the benzene ring present at the oxygen side of the carbamate molecule had a significant impact on the activity.  相似文献   
96.
97.
Empirical validation of the Essen-Möller probability of paternity.   总被引:1,自引:0,他引:1       下载免费PDF全文
The validity of the Essen-Möller formulation probability of paternity is supported by demonstrating its correctness in a model genetic system--the ABO system. An analysis was made of 1,393 paternity cases typed uniformly for HLA-A and -B, ABO, Rh, and MNSs, in which the mother named one man only as the child''s father and in which both mother and putative father identified themselves as Caucasian. For purposes of analysis, putative fathers not excluded from paternity by the four systems tested were regarded as actual fathers. The joint distribution of observed triplets of ABO phenotypes is shown to be statistically consistent with expected values, and the fractions of "true" fathers for a given triplet closely approximated the probability of paternity calculated using a realistic prior probability. Recent allegations of fallaciousness of the method by Li and Chakravarty and Aickin are discussed in terms of the results presented.  相似文献   
98.
Calculation of probability of paternity using DNA sequences.   总被引:5,自引:2,他引:3       下载免费PDF全文
This paper formally incorporates allele measurement error into the Essen-Möller version of the probability of paternity. For highly polymorphic genetic systems, an approximate solution to the problem is developed resulting in simple formulas. The DNA sequence of the D14S1 region provided a practical example for testing this approximation. For these sequences, allelic uncertainty arises from determining length of DNA fragments from mobility in gel electrophoresis. D14S1 and standard test results from 35 paternity cases establish the validity of our computational method.  相似文献   
99.
Increasing heat shock protein 70 (HSP70) in aged and/or insulin-resistant animal models confers benefits to healthspan and lifespan. Heat application to increase core temperature induces HSPs in metabolically important tissues, and preliminary human and animal data suggest that heated hydrotherapy is an effective method to achieve increased HSPs. However, safety concerns exist, particularly in geriatric medicine where organ and cardiovascular disease commonly will preexist. We evaluated young vervet monkeys compared to old, insulin-resistant vervet monkeys (Chlorocebus aethiops sabaeus) in their core temperatures, glucose tolerance, muscle HSP70 level, and selected safety biomarkers after 10 sessions of hot water immersions administered twice weekly. Hot water immersion robustly induced the heat shock response in muscles. We observed that heat-treated old and young monkeys have significantly higher muscle HSP70 than control monkeys and treatment was without significant adverse effects on organ or cardiovascular health. Heat therapy improved pancreatic responses to glucose challenge and tended to normalize glucose excursions. A trend for worsened blood pressure and glucose values in the control monkeys and improved values in heat-treated monkeys were seen to support further investigation into the safety and efficacy of this intervention for metabolic syndrome or diabetes in young or old persons unable to exercise.  相似文献   
100.
The use of topical and oral adenosine derivatives in HIV prevention that need to be maintained in tissues and cells at effective levels to prevent transmission prompted us to ask whether estradiol could influence the regulation of catabolic nucleotidase enzymes in epithelial cells and fibroblasts from the upper and lower female reproductive tract (FRT) as these might affect cellular TFV-DP levels. Epithelial cells and fibroblasts were isolated from endometrium (EM), endocervix (CX) and ectocervix (ECX) tissues from hysterectomy patients, grown to confluence and treated with or without estradiol prior to RNA isolation. The expression of nucleotidase (NT) genes was measurable by RT-PCR in epithelial cells and fibroblasts from all FRT tissues. To determine if sex hormones have the potential to regulate NT, we evaluated NT gene expression and NT biological activity in FRT cells following hormone treatment. Estradiol increased expression of Cytosolic 5′-nucleotidase after 2 or 4 h in endometrial epithelial cells but not epithelial cells or fibroblasts from other sites. In studies using a modified 5′-Nucleotidase biological assay for nucleotidases, estradiol increased NT activity in epithelial cells and fibroblasts from the EM, CX and ECX at 24 and 48 h. In related studies, HUVEC primary cells and a HUVEC cell line were unresponsive to estradiol in terms of nucleotidase expression or biological activity. Our findings of an increase in nucleotidase expression and biological activity induced by estradiol do not directly assess changes in microbicide metabolism. However, they do suggest that when estradiol levels are elevated during the menstrual cycle, FRT epithelial cells and fibroblasts from the EM, CX and ECX have the potential to influence microbicide levels that could enhance protection of HIV-target cells (CD4+T cells, macrophages and dendritic cells) throughout the FRT.  相似文献   
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