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Insomnia is the most frequent sleep disorder and a public health concern that increased during the Covid 19 pandemic. Fully restrictive lockdowns during Covid are interesting periods to examine the impact of environmental and behavioural changes on the emergence of insomnia symptoms. In this cross-sectional study we aimed to (1) determine the main factors associated with insomnia symptoms during a Covid-19 fully restrictive lockdown examining the associated daily life alterations and (2) create a predictive model of insomnia symptoms. We used the data drawn from the “Covid-RythmE” study that reached volunteers from the general French population through an online survey during the last 2 weeks of the 2 month full lockdown. Associations with insomnia symptoms were tested and significant associations were entered in a Backward Stepwise Logistic Regression (BSLR) to assess the best combination to classify individuals with or without insomnia symptoms. From the 1624 participants, 50.64% suffered from mild to severe insomnia symptoms as assessed by the ISI. The best combination for explaining insomnia symptoms with 74.26% of accuracy included: age (OR = 1.15), females (OR = 1.26), smaller home sizes (OR = 0.77), environmental noises (OR = 1.59), anxiety symptoms (OR = 1.24), depressive symptoms (OR = 1.15), regularity of sleep–wake schedules (OR = 1.25), exposure to screen during the morning (OR = 1.13), and LED light during the evening (OR = 1.17). Thus, lifestyle schedule and exposure to natural synchronizers such as light, are primordial in considering in insomnia physiopathology, prevention and treatment, as well as the associated mental health status.  相似文献   
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Rett syndrome is a severe neurodevelopmental disorder of unknown etiology, occurring almost exclusively in female patients. The etiology and functional significance of plasma carnitine deficiency seen in some patients with Rett syndrome is unknown. To investigate whether L-carnitine might be of benefit in Rett syndrome, a randomized, placebo-controlled, double-blind crossover trial of L-carnitine has been completed in 35 subjects. Eight-week treatment phases were completed for both a placebo and L-carnitine. Outcome was measured by parents/caregivers and at medical follow-up using three established tools: the Rett Syndrome Motor Behavioral Assessment, the Hand Apraxia Scale, and the Patient Well-Being Index. Analysis comparing change between baseline and week 8 of treatment for L-carnitine and the placebo showed that both parents/caregivers and medical follow-up detected improvements in the subjects' well-being. In addition, medical review showed an improvement on the Hand Apraxia Scale for a higher proportion of girls on L-carnitine. Identification of predictors of clinical improvement has been limited by the power of the study. These findings suggest that L-carnitine is of benefit in some patients with Rett syndrome. While L-carnitine did not lead to major functional changes in ability, the type of changes reported could still have a substantial impact on the girls and their families. Information is still needed, however, to determine if only subgroups of girls with the disorder are responsive to L-carnitine and the appropriate duration of therapy.  相似文献   
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The present study investigated the effects of dietary oltipraz on cigarette smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats were exposed daily to sidestream cigarette smoke in a whole- body exposure chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained on control diet while another group received the same diet supplemented with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz, starting 1 week prior to initiation of smoke exposure until the end of the experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated 32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5 predominated in both the lung and the heart while adduct nos 3 and 2 predominated in the trachea and bladder, respectively. Quantitative analysis revealed that the total adduct level was the highest in lungs (270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48 adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides) and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz treatment reduced the adduct levels in lungs and bladder by >60%, while the reduction in lungs in the low-dose group was approximately 35%. In trachea, the effect of low and high dietary oltipraz on smoke DNA adduction was equivocal, while smoke-related DNA adducts in the heart were minimally inhibited by high-dose oltipraz. In a repeat experiment that employed a 3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to inhibit the formation of DNA adducts in rat lungs and trachea by 80 and 65%, respectively. These data clearly demonstrate a high efficacy of oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts in the target tissues.   相似文献   
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Development of resistance to cytotoxic agents is a major limitation to their clinical use. Novel compounds are synthesized with a view to develop non-cross-resistant, less toxic and more potent activity. The detection of the anti-tumour properties of the inorganic compound cisplatin stimulated a broad search for other metal-containing complexes. Titanocene dichloride was synthesized on this basis and has shown potent anti-neoplastic activity in experimental animals. We have examined the in vitro activity of titanocene dichloride in two pairs of platinum-sensitive and resistant human ovarian carcinoma cell lines, A2780/2780CP and CH1/CH1cisR, and in mutated p53- and bcl-2-transfected clones of A2780 cells. A time- and concentration-dependent anti-proliferative effect was observed in all cell lines treated with titanocene dichloride. The drug was found to significantly overcome platinum resistance in the 2780CP and the CH1 cisR cell lines and in the bcl-2 and the mutant p53 transfectants of A2780 cells. Titanocene dichloride induced a block in late S/early G2 phase of the cell cycle; however apoptotic cell death occurred from any phase of cycle. Titanium-DNA adducts were detected in A2780 cells treated with titanocene dichloride using atomic absorption spectrometry, suggesting that DNA may be a target for this drug. In agreement with this finding, p53 accumulated rapidly in drug-treated A2780 cells, indicative of a role for titanocene dichloride as a DNA-damaging agent. We have also performed studies to determine whether titanocene dichloride could demonstrate synergy with other cytotoxic agents in vitro. Isobologram analysis of cytotoxicity data obtained suggests that the combination of titanocene dichloride and 5-fluorouracil (5-FU) is synergistic. The potent in vivo anti-tumour activity of this compound, supported by the encouraging results from two phase I clinical trials, suggests that titanocene dichloride could be a promising novel chemotherapeutic agent.  相似文献   
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Inactivation of the p53 tumor suppressor gene has been implicated in the pathogenesis of numerous human cancers, including osteosarcomas. Appendicular osteosarcomas of the dog appear to be a good model for their human equivalent with regard to biologic behavior, epidemiology and histopathology. We individually screened exons 5-8 of the p53 gene for mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to compare the role of this gene in human and canine osteosarcoma tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with one tumor possessing two mutations within different exons. Of these, seven were missense mutations and the eighth was a 'silent' mutation potentially affecting the exon 6-7 splicing region. Five of the missense mutations were located in highly conserved regions IV and V, while another corresponded with the highly conserved codon 220 mutational hotspot located outside the conserved domains. The locations and types of mutations were nearly identical to those reported in human cancer. These findings provide strong evidence of the involvement of p53 mutations in the development of canine appendicular osteosarcomas. Canine osteosarcomas appear to be a promising model for their human equivalent on a clinical, pathologic, and molecular level.   相似文献   
17.
Placenta percreta complicating pregnancy in the first trimester is extremely rare, and only a few cases have been reported in the literature. We recently reported on a patient with risk factors for placenta percreta that presented as first trimester fetal demise, unresponsive to medical management with prostaglandin. The patient required an emergency hysterectomy to control the bleeding after uterine curettage, and was complicated by severe consumption coagulopathy. This rare entity can lead to significant mortality and morbidity, particularly in the background of increased prevalence of the disease and its associated risk factors, and the large number of spontaneous and induced abortions performed worldwide. Therefore, we also reviewed all reported cases of first-trimester placenta percreta in the literature to increase the awareness of physicians and to highlight the clinical features and essentials of the management.  相似文献   
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