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71.
72.
The use of fasciocutaneous flaps for the reconstruction of lower leg soft-tissue defects inflicted during the bombing of our country is presented in this case report. The experience with 9 patients with soft-tissue defects of the lower leg is presented with the aim of examining the possibilities of war-wound reconstruction. The results of the earlier use of fasciocutaneous flaps in the lower leg reconstruction as well as the those obtained during the reconstruction of the lower leg soft-tissue defects in war wounds was proven to be safe and reliable method of the reconstructions of severe lower leg injuries, particularly of its distal segment and the malleolus region.  相似文献   
73.
Cattle are an important reservoir of Escherichia coli O157:H7 leading to contamination of food and water, and subsequent human disease. This pathogen colonizes its hosts by producing several proteins such as Tir and EspA that are secreted by a type III secretion system. These proteins play a role in colonization of the intestine, suggesting that they might be useful targets for the development of a vaccine to reduce levels of this organism in cattle. Vaccination of cattle with proteins secreted by E. coli O157:H7 significantly reduced the numbers of bacteria shed in feces, the numbers of animals that shed, and the duration of shedding in an experimental challenge model. Vaccination of cattle also significantly (P=0.04) reduced the prevalence of E. coli O157:H7 in a clinical trial conducted in a typical feedlot setting. This strategy suggests it is possible to vaccinate cattle to decrease the level of E. coli O157:H7 shedding for the purpose of reducing the risk of human disease.  相似文献   
74.
75.
6-((4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-propionyl)amino)hexanoic acid ryanodine (BODIPY-ryanodine) binding and Ca(2+) imaging were used to study the properties of ryanodine receptors (RyRs) and cytoplasmic Ca(2+) (Ca) changes in neurons cultured from the embryonic rat hippocampus during the earliest stages of differentiation. Baseline Ca levels declined from 164 +/- 5 (SD) nM at early stages to 70 +/- 4 nM in differentiated neurons. Fluorescent BODIPY-ryanodine binding signals identified activated RyRs in somata, which were eliminated by removal of external Ca(2+) or by blockage of Ca(2+) entry through L-type but not N-type Ca(2+) channels. The GABA synthesis inhibitor 3-mercaptopropionic acid completely abolished ryanodine binding. Caffeine or K(+)-depolarization inhibited the activity of RyRs at very early stages of differentiation but had stimulatory effects at later stages after a network of processes had formed. BayK-8644 stimulated RyRs throughout all regions of all differentiating cells. The results suggest that in differentiating embryonic hippocampal neurons the activity of RyRs is maintained via Ca(2+) entering through L-type Ca(2+) channels. The mode of activation of L-type voltage-gated Ca(2+) channels with either membrane depolarization or specific pharmacological agents affects the coupled activity of RyRs differently as neurons differentiate processes and networks.  相似文献   
76.
In order to determine the frequency, severity of poisoning, and the efficacy of the applied therapeutic measures, retrospective study of 391 patients treated for acute drug poisoning was performed during one-year period at the Clinic for Emergency and Clinical Toxicology and Pharmacology. In 49 (12.5%) patients cardiovascular agents were the cause of poisoning, most frequently beta-blockers and calcium antagonists (77.5%). Poisoning with antihypertensive agents was registered in 12.2% of patients, antiarrhythmics in 8.2%, and cardiotonics in 2.1%. Beta-blockers and calcium antagonists caused severe poisoning in over 40% of cases. Predominant clinical manifestations were registered on cardiovascular system, while central nervous system effects occurred secondary to cardiotoxicity. Symptomatic and supportive measures were performed most frequently, while specific agents, glucagon, calcium salts, and others, were used less often.  相似文献   
77.
One hundred seventeen women were reexamined within 6 months after presenting with genital herpes. Swabs for virus isolation were taken from the cervix whether or not lesions were observed. Herpesvirus type II was isolated from 30 of 67 patients with recurrent disease, but also from 5 of 50 women during periods when there were no signs or symptoms of illness. The epidemiologic importance of virus shedding from asymptomatic women is discussed.  相似文献   
78.
Patients who have survived myocardial infarction (MI), compared to the general population, have an increased risk of reinfarction, myocardial revascularization, and death. In this study we investigated the prognostic significance of the predictors of the risk for adverse coronary events in 118 patients, both male and female, with a confirmed diagnosis of MI in the last 3 years. The predictors of reinfarction, revascularization and death in patients who survived MI were: poor adherence to hypolipemics (hazard ratio [HR] 3.06, p=0.006), physical inactivity (HR 2.22, p=0.056), the number of variable risk factors (HR 1.29, p=0.025), and age (HR 1.06, p=0.007). After the inclusion of the invariable risk factors in the model of multivariant analysis, the following factors were singled out as significant predictors of the risk: gender (HR 3.86, p=0.0015), physical inactivity (HR 2.38, p=0.007), change in the level of triglycerides (HR 1.49, p=0.040), change in the number of variable risk factors (HR 1.41, p=0.0007), and age (HR 1.05, p=0.009). A 3-year follow-up of the patients who survived the first MI and who were enrolled in this study of secondary prevention demonstrated that physical inactivity, the number of variable risk factors and age significantly contributed to an increased risk of reinfarction, revascularization, and death.  相似文献   
79.
An albumin-simian virus 40 (SV40) large T-antigen (T-Ag) transgenic model and a chemically induced model of multistage hepatocarcinogenesis were created in our laboratory to study the molecular mechanisms involved in the genesis and progression of neoplasia in the rat liver. In the study presented here, these two models of rat hepatocarcinogenesis were used to perform a comparative mutational analysis of three tumor suppressor genes involved in hepatic neoplastic growth. By using polymerase chain reaction-single strand conformation polymorphism analysis and sequencing, exons 5-8 of the p53 tumor suppressor gene and a region between nt 4325 and 4479 of the rat mannose 6-phosphate/insulin-like growth factor 2 receptor (M6p/Igf2r) coding sequence were screened. The latter is homologous to the human M6P/IGF2r coding sequence which is mutated in human hepatocellular carcinoma. A complete single strand conformation polymorphism analysis of the entire coding region of the rat adenomatous polyposis coli (Apc) gene was also performed for the first time in rat tumorigenic samples. Twenty-six chemically induced rat hepatocellular carcinomas, 21 neoplasms from the livers of SV40 T-Ag animals, and five immortalized hepatic cell lines from the transgenic rats were evaluated. None of the hepatic tumors exhibited mutations in the regions analyzed. The albumin-SV40 T-Ag transgenic cell line L-60, derived from normal hepatic tissue, had two mutations in contiguous codons of exon 5 of the p53 gene: a GGT --> GTT missense transversion in codon 183 and a silent mutation in codon 184. The transversion, which may affect the DNA binding domain of the p53 protein, probably originated during cell culture and may have been positively selected because it gave a growth advantage to the mutated cells. The studied region of the M6p/Igf2r gene was not found to be mutated in these two models of rat hepatocarcinogenesis. Although M6p/Igf2r, Apc, and p53 have been shown to be mutated in a variety of human hepatic proliferative diseases, our results indicate that aberrations in these genes may not be necessary for liver carcinogenesis in the rat.  相似文献   
80.
The authors reviewed the clinical results of leg lengthening by distraction osteogenesis, where two different osteotomy techniques were used: classical corticotomy according to Ilizarov or osteoclasis. Evaluation of results of 64 patients were bases on orthopedic examination and detailed X-ray analysis which included criteria assessing osseous regeneration rate. In those cases where osteoclasis was performed bone formation in the distraction gap was faster than in after osteotomy. An accelerated rate of regenerate formation, as well as a more active regenerate remodelling was observed. This allowed to shorten the time of external fixator application and an earlier rehabilitation.  相似文献   
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