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Nicotinamide N-methyltransferase (NNMT) has been linked to obesity and diabetes. We have identified a novel nicotinamide (NA) analog, compound 12 that inhibited NNMT enzymatic activity and reduced the formation of 1-methyl-nicotinamide (MNA), the primary metabolite of NA by ~80% at 2?h when dosed in mice orally at 50?mg/kg.  相似文献   
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Perfluorooctane sulfonate (PFOS) is an endocrine disruptor chemical (EDC) with potentially adverse effects on the male reproductive system. Pachypodol (5,4′-dihydroxy-3,7,3′-trimethoxyflavone) is a promising flavonoid isolated from Pogostemon cablin (Blanco) Benth that shows a broad range of pharmacological properties. However, the potential curative effects of pachypodol on testicular toxicity are not available until now. Therefore, this research was proposed to examine the efficiency of pachypodol against PFOS-induced testicular toxicity in adult male rats. The experiments were conducted on Sprague-Dawley rats (n = 48), which were equally distributed into four groups: control, PFOS (20 mg/kg), PFOS + Pachypodol (20 mg/kg + 10 mg/kg respectively), and Pachypodol (10 mg/kg). After 56 days of treatment, testes were excised by slaughtering rats, weighed, and stored till further analysis. The estimated parameters include biochemical markers, spermatogenic indices, hormonal and histopathological profiles. PFOS exposure disturbed the biochemical profile by altering the antioxidant/oxidant balance. For instance, it decreased the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GSR) while increasing the concentration of reactive oxygen species (ROS) and level of thiobarbituric acid reactive substances (TBARS). PFOS intoxication also led to a notable decline in viability, motility, epididymal sperm count, and the number of HOS coiled-tail sperms, whereas the higher level of abnormality in the head, mid-piece, and tail of sperms were observed. Besides, it lowered luteinizing hormone (LH), follicle-stimulating hormone (FSH), and plasma testosterone. In addition, PFOS exposure led to histopathological damages in testicles. However, pachypodol treatment potently alleviated all the illustrated impairments in testes. Conclusively, our results demonstrate the promising free-radical scavenging activity of pachypodol, a novel phytochemical, against the PFOS-instigated testicular dysfunctions.  相似文献   
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Studies were undertaken to explain the ability of Listeria monocytogenes to grow at low temperatures in a chemostat. It was found that when grown in continuous culture at a dilution rate of 0·02 h−1 L. monocytogenes had a lower proportion of anteiso -17:0, and a higher proportion of anteiso -15:0, and smaller chain fatty acids when grown at 10°C compared to 30°C. A previously unreported glycolipid was only seen after growth at low temperature. Growth temperature had no effect on the rate of glucose uptake.  相似文献   
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Neurulation in vertebrates is an intricate process requiring extensive alterations in cell contacts and cellular morphologies as the cells in the neural ectoderm shape and form the neural folds and neural tube. Despite these complex interactions, little is known concerning the molecules that mediate cell adhesion within the embryonic neural plate and neural folds. Here, we demonstrate the requirement for NF-protocadherin (NFPC) and its cytosolic partner TAF1/Set for proper neurulation in Xenopus. Both NFPC and TAF1 function in cell-cell adhesion in the neural ectoderm, and disruptions in either NFPC or TAF1 result in a failure of the neural tube to close. This neural tube defect can be attributed to a lack of proper organization of the cells in the dorsal neural folds, manifested by a loss in the columnar epithelial morphology and apical localization of F-actin. However, the epidermal ectoderm is still able to migrate and cover the open neural tube, indicating that the fusions of the neural tube and epidermis are separate events. These studies demonstrate that NFPC and TAF1 function to maintain proper cell-cell interactions within the neural folds and suggest that NFPC and TAF1 participate in novel adhesive mechanisms that contribute to the final events of vertebrate neurulation.  相似文献   
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Objectives: To date a number of studies have examined the association between maternal weight and testicular cancer risk although results have been largely inconsistent. This systematic review and meta-analysis investigated the nature of this association. Methods: Search strategies were conducted in Ovid Medline (1950–2009), Embase (1980–2009), Web of Science (1970–2009), and CINAHL (1937–2009) using keywords for maternal weight (BMI) and testicular cancer. Results: The literature search produced 1689 hits from which 63 papers were extracted. Only 7 studies met the pre-defined criteria. Random effects meta-analyses were conducted. The combined unadjusted OR (95% CI) of testicular cancer in the highest reported category of maternal BMI compared with the moderate maternal BMI was 0.82 (0.65–1.02). The Cochran's Q P value was 0.82 and the corresponding I2 was 0%, both indicating very little variability among studies. The combined unadjusted OR (95% CI) for testicular cancer risk in the lowest reported category of maternal BMI compared to a moderate maternal BMI category was 0.88 (0.65–1.20). The Cochran's Q P value was 0.05 and the corresponding I2 was 54%, indicating evidence of statistical heterogeneity. The combined unadjusted OR (95% CI) of testicular cancer risk per unit increase in maternal BMI was 1.01 (0.97–1.06). The Cochran's Q test had a P value of 0.05 and the corresponding I2 was 55% indicating evidence of statistical heterogeneity. Conclusion: This meta-analysis, which included a small number of studies, showed that a higher maternal weight does not increase the risk of testicular cancer in male offspring. Though an inverse association between high maternal BMI and testicular cancer risk was detected, it was not statistically significant. Further primary studies with adjustment for appropriate confounders are required.  相似文献   
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