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991.
Cerebral sinus-venous thrombosis (CSVT) is a rare life-threatening disease with an estimated annual incidence of 3–4 cases per million in adults and 7 cases per million in neonates. Brain tumors, cerebral infections and traumas are local risk factors for CSVT, but the commonest encountered risk factors are oral contraceptive use, pregnancy and puerperium that make the disease predominant in female sex. In 15–20 % of patients, the disease remains unprovoked, i.e., occurring in the absence of predisposing factors. Thrombophilic abnormalities either inherited [deficiency of the natural anticoagulant proteins antithrombin, protein C or protein S, mutations in the factor V gene (factor V Leiden) or prothrombin gene (prothrombin G20210A)] or acquired (antiphospholipid antibodies) are worthy to be investigated in patients with CSVT, as well as hyperhomocysteinemia. In a small proportion of patients, CSVT is the first manifestation of a myeloproliferative neoplasm. The proportion of patients with recurrent CSVT is low, but venous thromboembolism (deep vein thrombosis in the lower limbs or pulmonary embolism) can develop particularly in patients with a first idiopathic CSVT. In the past decade, there has been increasing evidence that early diagnosis and anticoagulant treatment reduce morbidity of CSVT and improve survival. However, the optimal duration of anticoagulant treatment is not well established, because limited information is available on the rate of CSVT recurrence after anticoagulant discontinuation.  相似文献   
992.
Atherosclerosis is a complex inflammatory disease comprising multiple plaque phenotypes. The development of advanced atheromatous plaques with necrotic core represents the result of the invasion of lipid pools by macrophages. The release of activated proteolytic enzymes degrades the surrounding tissue and contributes to the formation of vulnerable plaque. Thinning of the fibrous cap and necrotic core expansion are considered to be critical for the progression toward plaque rupture and acute thrombosis. The pathogenic mechanisms leading the progression of atherosclerotic lesions are various and involve endothelial cells, inflammatory cells, and platelets. Nonalcoholic fatty liver disease (NAFLD) includes a spectrum of diseases ranging from simple fatty liver to nonalcoholic steatohepatitis (NASH) and may progress to cirrhosis and hepatocellular carcinoma. The prevalence of this pathology is quite high in the general population and is one of the most important causes of liver-related morbidity and mortality in children. NAFLD is considered the hepatic feature of the metabolic syndrome and this has stimulated interest in its possible role in the atherosclerosis development. Clinical observations indicated that NAFLD might be an independent risk factor for coronary artery disease. Moreover, NASH may increase atherosclerotic and cardiovascular risks by local overexpression of inflammatory mediators, endothelial damage, and regulators of blood pressure. NASH development is correlated with hepatic progenitor cell activation and the release of proatherogenic adipokines. These aspects suggest the necessity for an early therapeutic intervention in NASH patients, not only for ameliorating the liver injury, but also for improving the systemic proatherogenic state.  相似文献   
993.
ObjectiveThis review seeks to establish the incidence of adverse outcomes associated with minimally invasive tissue extraction at the time of surgical procedures for myomas.Data SourcesArticles published in the following databases without date restrictions: PubMed, EMBASE, Web of Science, Cochrane Database of Systematic Reviews and Trials. Search was conducted on March 25, 2020.Methods of Study SelectionIncluded studies evaluated minimally invasive surgical procedures for uterine myomas involving morcellation. This review did not consider studies of nonuterine tissue morcellation, studies involving uterine procedures other than hysterectomy or myomectomy, studies involving morcellation of known malignancies, nor studies concerning hysteroscopic myomectomy. A total of 695 studies were reviewed, with 185 studies included for analysis.Tabulation, Integration, and ResultsThe following variables were extracted: patient demographics, study type, morcellation technique, and adverse outcome category. Adverse outcomes included prolonged operative time, morcellation time, blood loss, direct injury from a morcellator, dissemination of tissue (benign or malignant), and disruption of the pathologic specimen.ConclusionComplications related to morcellation are rare; however, there is a great need for higher quality studies to evaluate associated adverse outcomes.  相似文献   
994.
The pyrimidine nucleosides uridine (URI) and cytidine (CYT), alone or associated with n-acetyl-glutamine (NAG), were injected acutely or subchronically to aged (26 months old) male rats of the Sprague-Dawley strain. Learning and memory abilities of the animals were studied with tests of avoidance behavior. The acquisition of active avoidance behavior was studied with the shuttle-box test. A step-through type of passive avoidance task was used to examine the retention of passive avoidance responses. The acquisition of the active avoidance behavior and the retention of the passive avoidance response were reduced in aged animals as compared with those of young animals. Neither the acute treatment of old rats with URI and CYT alone nor that associated with NAG exerted any effect on the behavioral tests. In contrast, the subchronic treatment with URI and CYT was followed by a facilitation of acquisition of active avoidance behavior in the shuttle box and of retention of passive avoidance responses in the dark box. A more potent effect on the acquisition of the shuttle-box behavior and on the retention of passive avoidance reaction was found in animals treated subchronically with the pyrimidine nucleosides associated with NAG. These effects may be related to the role of pyrimidines in the synthesis of ribonucleic acid, which is indispensable for learning and memory processes.  相似文献   
995.
The mechanisms of the bilirubin formation, transport, conjugation and biliary excretion have been extensively studied in the recent past, thereby allowing a more complete and rational approach to the old, but still somehow unknown symptom of jaundice and cholestasis. Based on the most recent physiologic and biochemical data, jaundice and cholestasis have been revisited during and international meeting. This report summarizes what has been established in the field but, most importantly highlights what is still unknown and requires further investigation.  相似文献   
996.
OBJECTIVE: Endoscopic bilateral thoracic sympathicolysis (EBTS) is an effective and minimally invasive procedure used for patients with primary hyperhidrosis. The purpose of this study was to examine anxiety levels using standardized psychometric tools in hyperhidrosis patients before and after EBTS. METHODS: A total of 106 patients diagnosed with hyperhidrosis who underwent EBTS were asked to fill out a questionnaire before and 12 months after the procedure that elicited the following information: (a) symptoms associated with hyperhidrosis; (b) the patient's level of anxiety; and (c) the extent to which this anxiety was incapacitating in their daily life. All patients also completed State-Trait Anxiety Inventory (STAI) before and 12 months after the EBTS. RESULTS: Palpitations were reported preoperatively by 40% of patients versus 10% postoperatively, trembling of the hands in 24% versus 8%, facial blushing in 55% versus 11%, headache in 29% versus 9%, and non-specific epigastric pain in 19% versus 7%. Patients reported a marked improvement in the level of anxiety from a mean SD of 2.08+/-1.1 preoperatively versus 0.39+/-0.67 postoperatively (p<0.001), and the social impact (debilitating) of primary hyperhidrosis before and after surgery also showed significant improvement (p<0.001). The results of STAI showed significant improvement in the levels of anxiety after surgery compared with the preoperative levels and with established norms (p<0.001). CONCLUSIONS: Patients with primary hyperhidrosis that undergo EBTS presented a decrease in the level of anxiety and associated symptoms.  相似文献   
997.
The objective of this study was to test the hypothesis that chronic occupational exposure to high temperatures may be detrimental to male reproduction. The study was based on 92 healthy ceramics oven operators with a long exposure to high temperatures, and 87 controls, recruited from the shipment department of the same industry. Interviews with all subjects provided data on sociodemographic characteristics, health status, and fertility problems. Semen analysis was carried out on 46 of the workers exposed to high temperatures, and 14 of the controls, and included evaluation of the sperm concentration, morphology, and motility, including computer-assisted sperm motion analysis (velocity, linearity, ALH, BCF). The results of the questionnaire showed that exposed individuals had a higher incidence of childlessness and of self-reported difficulty in conceiving than controls. The semen analysis showed no significant differences except in sperm velocity. Although differences in semen parameters, taken singly, were not statistically significant, the overall evaluation of the sperm parameters indicated a higher prevalence of pathologic sperm profiles among the exposed compared to the controls.  相似文献   
998.
This study was undertaken to assess the metabolic effect of fetal and adult hepatocyte transplantation in the Gunn rat, genetically incapable of bilirubin conjugation. A comparison was made between fetal and adult hepatocytes transplanted into the spleen, and those injected into polytetrafluoroethylene (PTFE) solid supports that had previously been implanted intraperitoneally. Between 4 and 12 weeks after intrasplenic transplantation of adult liver cells, serum bilirubin was significantly decreased when compared with control animals (39.6 +/- 5.6%; P less than 0.01 vs. controls). Intrasplenic transplantation of fetal hepatocytes resulted in a maximal decrease of 33.2 +/- 9.1% at 8 weeks postoperatively (P less than 0.02 vs. controls). Similar declines of serum bilirubin levels were found after transplantation of adult or fetal liver cells into the solid supports. At 12 weeks after transplantation, bilirubin conjugates were detectable in the bile of all animals that underwent intrasplenic hepatocyte transplantation and in 60% of those that underwent the solid support procedure, whereas none could be detected in control animals. Histological evidence of surviving cells was obtained in all but one animal at 12 weeks, and confirmed at 12 months postoperatively. It is concluded that the PTFE solid support technique offers an attractive alternative to the intrasplenic route, and that both fetal and adult hepatocytes, transplanted in either way still exert their conjugating activity after 12 weeks.  相似文献   
999.
1000.
The phosphorylcholine precursor, L-alpha-glycerylphosphorylcholine (alpha-GPC), was injected at the dose of 100 mg/kg/day for 20 days to aged male rats of the Sprague-Dawley strain, 24 months old, showing a deficit of learning and memory capacity. The drug was also administered to rats with amnesia induced pharmacologically with bilateral injections of kainic acid into the nucleus basalis magnocellularis (NBM). Learning and memory capacity of the animals, studied with tests of active and passive avoidance behavior, was improved after treatment with alpha-GPC in all experimental groups. These results indicate that this drug affects cognitive mechanisms in the rat through an involvement of central neurotransmission.  相似文献   
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