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71.
After absorption by the organism, polychlorinated biphenyls (PCBs) cross cellular membranes and pass into blood vessels and the lymphatic system. It is generally in the liver, adipose tissues, brain and skin that we find the strongest concentrations of PCBs. Herbal medicine remains as a discipline intended to treat and to prevent certain functional disorders and/or pathologies caused by oxidative stress, which can be induced by pesticides, medicines or pollutants. The objective of this study is to verify the toxic and oxidative effects of PCBs and to investigate the protective effect of ginger (Zingiber officinale) in the liver of male rats of the “Wistar” strain. These rats are divided into 6 groups: a control group (T), two groups treated with PCB at two different concentrations (P1 and P2), a group treated with ginger extract (G), a group pretreated with ginger extract and then injected with the first concentration of PCBs (P1G), and a group pretreated with ginger and then injected with the second concentration of PCBs (P2G). The results showed that the administration of PCBs led to an increase in the relative weight of the liver, and a significant increase in all of the hepatic biomarker levels (glucose, cholesterol, triglycerides, AST, ALT, and LDH) in the serum. Furthermore, an increase in the rate of lipid peroxidation and a decrease in the antioxidant enzyme activities (catalase, superoxide dismutase and glutathione peroxidase) were observed under the influence of PCBs in the liver. The histological test showed that the PCBs induced hepatocyte vacuolization, prominent and peripheralized nuclei, hepatocellular hypertrophy and turgor of the vein in the centriacinar regions. Pretreatment with ginger extract restored all of the biochemical and oxidative parameters to the normal values and reduced the injuries caused by the PCBs. In conclusion, in our experimental conditions, ginger effectively protects the liver against the hepatotoxic effects induced by PCBs.

After absorption by the organism, polychlorinated biphenyls (PCBs) cross cellular membranes and pass into blood vessels and the lymphatic system.  相似文献   
72.
Various studies in the field of sexual and reproductive health have focused on understanding the relationship between the gestation period and sexual behavior. The majority of such research suggests that during pregnancy, both sexual desire and frequency of sexual relations decrease. The objective of the present study was to investigate whether there are any influences of gestational period on the sexual behavior, and to identify differences in sexual behavior among women before and during pregnancy. A cross-sectional analytic study design was carried out on a sample of 190 women attending the outpatient clinics of Assiut university hospital were consecutively recruited. Data was collected using a structured questionnaire to collect socio-demographic data, obstetric history, and information about women's sexual desire and practice of sexual intercourse before and during pregnancy, as well as their perceptions and beliefs. The mean age of women was 26.7 +/- 5.4 years. The results showed that 37.4% of women had better sexual desire during the whole of pregnancy, 47.9% had sexual satisfaction during the second trimester of pregnancy, and 75.7% felt change in sexual intercourse during pregnancy. A considerable proportion (43.7%) believed that sexual intercourse during pregnancy could lead to problems. The number of intercourses before and during pregnancy were positively correlated (r = 0.80, p < 0.001). Multiple logistic regression model revealed that history of abortion was the only statistically significant negative independent predictor of the practice of sexual intercourse during pregnancy. It is recommended that health care providers, especially nurses, should educate and counsel women regarding the safety of sexual intercourse during pregnancy if no medical risk is present.  相似文献   
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Background

Individuals with an “At Risk Mental State” have a 20-30% chance of developing a psychotic disorder within two years; however it is difficult to predict which individuals will become ill on the basis of their clinical symptoms alone. We examined whether mismatch negativity (MMN) could help to identify those who are particularly likely to make a transition to psychosis.

Method

41 cases meeting PACE criteria for the At Risk Mental State (ARMS) and 50 controls performed a duration-deviant passive auditory oddball task whilst their electroencephalogram was recorded. The amplitude of the MMN wave was compared between groups using linear regression. The ARMS subjects were then followed for 2 years to determine their clinical outcome.

Results

The MMN amplitude was significantly reduced in the ARMS group compared to controls. Of the at-risk subjects who completed followed up (n = 41), ten (24% of baseline sample) subsequently developed psychosis. The MMN amplitude in this subgroup was significantly smaller across all three recording sites (FZ, F3 and F4) than in the ARMS individuals who did not become psychotic. Conclusion: Among those with the ARMS, MMN amplitude reduction is associated with an increased likelihood of developing frank psychosis.  相似文献   
75.
The chemical composition, antibacterial, and antifungal activities of the volatile fractions from fresh and dried leaves of three Olea europaea L. cultivars from Tunisia (Neb jemel, Chemchali and Chemlali) have been studied. The volatile components were obtained via hydrodistillation and analyzed by GC–MS. The major constituents were (E)-3-hexenol, 3-ethenylpyridine, (E)-β-damascenone and phenylethyl alcohol, but their percentages varied according to the treatment of the leaves. Antioxidant activities were determined applying DPPH and ABTS+ radical-scavenging assays. In general, antioxidant activity of the volatile fraction obtained from fresh leaves was superior to that obtained from dried leaves. The antibacterial and antifungal activities of the volatile fractions from fresh and dried leaves were evaluated against four bacterial and four fungal strains. The volatile fractions showed significant antibacterial and antifungal effects. However, some differences were observed in the response for several microorganisms, because of the variability of the composition. This work gives further knowledge for extensive development of this medicinal plant.  相似文献   
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