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排序方式: 共有4889条查询结果,搜索用时 15 毫秒
1.
Fahad Ali Rahul Smita Jyoti Ambreen Fatima Saba Khanam Falaq Naz Yasir Hasan Siddique 《Scientia pharmaceutica》2016,84(2):361-377
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats. 相似文献
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Expression of TRIM22 mRNA in chronic hepatitis C patients treated with direct-acting antiviral drugs
Mariam Naveed Amjad Ali Nadeem Sheikh Shazia Rafique Muhammad Idrees 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2020,128(4):326-334
Hepatitis C is a global public health problem, and Pakistan is the second largest country in the globe with highest prevalence rate of hepatitis C virus (HCV). Until 2014, pegylated interferon (PEG-IFN) plus ribavirin (RBV) has been the standard therapy for HCV, however, owing to its adverse side effects and very low sustained virologic response (SVR) rates therapeutics trend is shifted toward direct-acting antivirals. Tripartite motif containing 22 (TRIM22) is a dynamic antiviral protein that can inhibit multiple viruses in vivo. Expression of TRIM22 mRNA has been linked to outcome of PEG-IFN and ribavirin therapy, where its higher expression leads to rapid virus clearance. However, in terms of therapy with direct-acting antiviral (DAA) or double DAA, impact of TRIM22 expression is largely unknown. These new drugs show more than 90% of SVR rates and lesser side effects and have proven to be better than IFN therapy. Endogenous IFN system suppresses various pathogens through the induction of antiviral effectors termed as interferon-stimulating genes (ISGs). We have studied the expression levels of one of these antiviral effectors, TRIM22 in response to sofosbuvir (SOF) and daclatasvir (DAC) in combination with RBV, using quantitative PCR in the peripheral blood mononuclear cells (PBMCs) of HCV-infected patients. We have observed sustained virus clearance in more than 90% of patients treated with DAA and double DAA and have seen the expression of TRIM22 to be higher in patients who attained SVR as compared to the untreated patients. We have also observed downregulation of TRIM22 in patients who failed to attain rapid virus clearance, and upregulation in those who achieved rapid clearance of virus. Genetic factors that determine the lower TRIM22 expression in these patients are needed to be explored that may also play a role in lower response to anti-HCV therapy. Endogenous IFN system and effects of antiviral proteins in response to DAA therapy is needed to be studied in order to better understand the host response toward these drugs to make them more effective. 相似文献
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Exposure to electromagnetic fields and the risk of leukemia 总被引:4,自引:0,他引:4
K Sheikh 《Archives of environmental health》1986,41(1):56-63
Evidence from animal experiments and human studies suggests that electromagnetic fields may be human leukemogens. Epidemiological studies of leukemia in occupational groups and in the general populations are reviewed. The results are inconsistent. In the few studies showing an association between exposure to electromagnetic fields and the risk of leukemia, the temporal relationship between exposure and effect was not established, the observed associations were weak, the dose-response relationships were based on qualitative levels of exposure without regard to the duration of exposure or secondary sources of exposure, and the risk ratios were probably biased due to the population selection procedures used and misclassification of exposure. The proportionate mortality or cancer incidence ratios are unreliable estimates of relative risk. Further epidemiological research is needed to establish an association between exposure to electromagnetic fields and the risk of leukemia. 相似文献
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D Loutradis K Stefanidis P Drakakis K Kallianidis A El Sheikh S Milingos K Siskos S Michalas 《Gynecological endocrinology》2003,17(2):101-106
The purpose of this study was to investigate the ovarian response and the receptivity of the endometrium in women pre-treated with micronized progesterone. Eighty-two normogonodotropic women undergoing in vitro fertilization were studied. Thirty received micronized progesterone 1500 mg/day from day 21 of the cycle for a minimum of 2 weeks, and 52 did not receive micronized progesterone (control group). A gonadotropin releasing hormone agonist (GnRH-a) was administered to all the patients in the follicular phase (flare-up). Twenty-five cycles were cancelled for fertilization failure due to male factor, 12 (40%) in the progesterone group and 13 (25%) in the control group (p = 0.271). There was no difference in the number of oocytes retrieved (7.3 +/- 5 vs. 8.2 +/- 4), fertilization rate (50.8% vs. 65%), clinical pregnancy rate (16.6% vs. 25%) or implantation rate (8% vs. 14%). In the progesterone group cases without fertilization, we performed two biopsies to evaluate the receptivity of the endometrium. Pinopode expression was noted 7 days after oocyte retrieval. It seems that the administration of micronized progesterone in the previous cycle does not affect the ovarian response to the combination of follicular phase GnRH-a and gonadotropins, nor the receptivity of the endometrium. 相似文献
8.
J-P Lefaucheur J-J Labat G Amarenco A-G Herbaut D Prat-Pradal J Benaim B Aranda M-C Arne-Bes V Bonniaud P-M Boohs K Charvier F Daemgen P Dumas J-P Galaup S Sheikh Ismael J Kerdraon P Lacroix D Lagauche E Lapeyre M Lefort A-M Leroi R-J Opsomer B Parratte J-G Prévinaire P Raibaut J-Y Salle M-C Scheiber-Nogueira J-M Soler M-F Testut C Thomas 《Clinical neurophysiology》2007,37(4):223-228
Entrapment of the pudendal nerve may be at the origin of chronic perineal pain. This syndrome must be diagnosed because this can result in the indication of surgical decompression of the entrapped nerve for pain relief. Electroneuromyographic (ENMG) investigation is often performed in this context, based on needle electromyography and the study of sacral reflex and pudendal nerve motor latencies. The limits of ENMG investigation, owing to various pathophysiological and technical considerations, should be known. The employed techniques do not assess directly the pathophysiological mechanisms of pain but rather correlate to structural alterations of the pudendal nerve (demyelination or axonal loss). In addition, only direct or reflex motor innervation is investigated, whereas sensory nerve conduction studies should be more sensitive to detect nerve compression. Finally, ENMG cannot differentiate entrapment from other causes of pudendal nerve lesion (stretch induced by surgical procedures, obstetrical damage, chronic constipation...). Thus, perineal ENMG has a limited sensitivity and specificity in the diagnosis of pudendal nerve entrapment syndrome and does not give direct information about pain mechanisms. Pudendal neuralgia related to nerve entrapment is mainly suspected on specific clinical features and perineal ENMG examination provides additional, but no definitive clues, for the diagnosis or the localization of the site of compression. In fact, the main value of ENMG is to assess objectively pudendal motor innervation when a surgical decompression is considered. Perineal ENMG might predict the outcome of surgery but is of no value for intraoperative monitoring. 相似文献
9.
Interpretive criteria for cefotetan in vitro susceptibility testing appear to be clinically relevant when applied to aerobic bacteria. To determine whether the same was true for anaerobic bacteria, we conducted a retrospective analysis of intraabdominal, gynecologic, and skin and skin structure infections treated with cefotetan. Of the infections, 202 contained at least one anaerobe isolate. Of the 51 patients, 47 (92.9%) from whom one or more cefotetan-resistant anaerobes were isolated were clinically cured or showed improvement. Similarly, cefotetan was efficacious for 95.4% of the patients harboring only cefotetan-susceptible anaerobes. Favorable bacteriologic responses were observed in 94.1% and 97.4% of these patient groups, respectively. The data suggests that the therapeutic utility of cefotetan against anaerobic bacteria cannot be accurately predicted on the basis of in vitro susceptibility test results alone but may be explained by a variety of factors, as discussed in this report. 相似文献
10.
J S Appelbaum R P Roos E F Salazar-Grueso A Buchman S Iannaccone R Glantz T Siddique R Maselli 《Neurology》1992,42(8):1488-1492
Although there are varied inheritance patterns in motor neuron disease (MND), the phenotype of MND is reported to be constant within these families, ie, cases of amyotrophic lateral sclerosis or primary lateral sclerosis do not occur in pedigrees with cases of spinal muscular atrophy. We describe four pedigrees whose members diverged in the phenotype of MND expressed. The intrafamilial variation of phenotype suggests a similar pathogenesis for some of the varied types of familial MND and the need for careful inquiry of family history in all patients with MND. 相似文献