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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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OBJECTIVE: Cardiac troponin I (cTnI) is a highly sensitive and specific marker for postoperative prediction of patients outcome after coronary artery bypass surgery (CABG). Whether preoperatively elevated cTnI levels similarly predict the outcome in patients scheduled for elective CABG is currently unknown. METHODS: Therefore, a possible correlation between preoperative cTnI levels and perioperative major adverse events and in-hospital mortality after CABG was investigated. CTnI was measured within 24h before surgery in 1405 out of 3124 consecutive elective CABG patients. Out of these patients, 1178 had a preoperative cTnI level below 0.1ng/ml (group 1), 163 patients had a cTnI level between 0.11 and 1.5ng/ml (group 2), and 64 patients had a cTnI level above 1.5ng/ml (group 3). CTnI levels, electrocardiograms, clinical data, adverse events and in-hospital mortality were recorded prospectively. Patients with ST-elevation myocardial infarction less than 7 days before surgery were excluded from the study. RESULTS: Perioperative myocardial infarction (PMI) occurred in 69/1178 patients (5.9%) in group 1, 14/163 patients (8.6%; odds ratio (OR) 1.5, 95% confidence interval (CI): 0.8-2.8) in group 2, and 11/64 patients (17.2%; OR 3.3, CI: 1.6-7.0) in group 3 (overall: P<0.001, Cochran-Armitage trend test). Low cardiac output syndrome (LCOS) occurred in 19/1178 patients (1.6%), 9/163 (5.5%; OR 3.6, CI: 1.5-8.5), and 7/64 patients (10.9%; OR 7.5, CI: 2.7-19.8) (overall: P<0.001, group 1 vs. group 2: P<0.002), respectively. In-hospital mortality was 1.7% in group 1 and 3.1% in group 2, but 6.3% (OR 3.9, CI: 1.1-12.5) in group 3 (overall: P<0.01, group 1 vs. group 2: P=NS). Intensive care and hospital stay were significantly longer in group 3 compared to groups 1 and 2. Univariate and multivariate logistic regression analysis confirmed the statistically significant relationship between cTnI and PMI, LCOS and in-hospital mortality, respectively (P<0.001). CONCLUSIONS: Risk stratification by measurement of cTnI levels within 24h before elective CABG clearly identifies a subgroup of patients with increased risk for postoperative adverse outcome and in-hospital mortality.  相似文献   
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The concentrations of cadmium, zinc, copper and metallothionein in the autopsy samples of liver among the inhabitants of Lód? (Poland) were determined. The cadmium levels were low in the range of 1.5 to 5.8 micrograms/g. The concentration of metallothionein determined by the Hg-method was high (0.160-1.665 mumol Hg/g); it was mainly a Zn-thionein. The percentage of hepatic zinc bound in the MT-fraction increased with the overall content of zinc in the liver. The elevation of zinc in the liver occurs in the proportion required for the saturation of metal-binding ligands of metallothionein. The role of cadmium remains less clear. Our results suggest that the metallothionein level in the liver increase significantly in response to elevated cadmium concentrations. This response, however, is in high excess to the demand which is justified stoichiometrically.  相似文献   
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Zusammenfassung Grundlagen: Die perkutane Diskektomie (PDE) wurde erstmals 1975 vonHijikata beschrieben. Es werden in dieser Studie die Operationsergebnisse der seit 1989 an der neurochirurgischen Abteilung der Landesnervenklinik Salzburg durchgeführten perkutanen Diskektomien retrospektiv analysiert. Methodik: Die perkutanen Diskektomien wurden über einen dorsolateralen Zugang unter Verwendung des Instrumentariums von Aeskulap? durchgeführt. Die Patienten wurden klinisch nachuntersucht, wobei der durchschnittliche Nachuntersuchungszeitraum 21,3 Monate betrug. Ergebnisse: Es wurde insgesamt bei 41 Patienten die PDE durchgeführt. 36,6% der Patienten waren postoperativ beschwerdefrei; 31,7% der Patienten erreichten ein gutes und 7,1% ein befriedigendes Operationsergebnis. Bei 10 Patienten war wegen fehlendem Therapieerfolg eine interlamin?re Diskusextraktion notwendig. Intra- und postoperative Komplikationen traten nicht auf. Schlu?folgerungen: Bei der perkutanen Diskektomie handelt es sich um eine erg?nzende Operationsmethode in der Bandscheibenchirurgie, die für wenige Patienten die Therapie der Wahl darstellt. Die Operationsergebnisse sind bei strenger Indikationsstellung den Ergebnissen der interlamin?ren Diskusextraktion vergleichbar.   相似文献   
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Timing of carotid endarterectomy after acute stroke   总被引:2,自引:0,他引:2  
An arbitrary delay of at least 6 weeks before performing carotid endarterectomy after acute stroke has been recommended based on anecdotal reports. This prolonged interval may increase the danger of recurrent neurologic deficit before surgery. From September 1978 to September 1988, carotid endarterectomy was performed on 140 patients at variable intervals after stroke. Eleven patients had temporary stroke, which left 129 patients with neurologic symptoms that persisted for 3 weeks or had a cortical infarct on CT scanning. A prospective therapeutic protocol was applied to 82 patients admitted with acute stroke. They were observed until neurologic recovery reached a plateau, based on clinical observation by a neurologist, before performing angiography and carotid endarterectomy (group I). Forty-seven patients were not seen until after recovery from stroke was established (group II). At initial presentation, the severity of neurologic deficit was classified as mild, moderate, or severe in 31%, 58%, and 11%, respectively. Recovery before operation was registered as complete in 11%, mild residual in 66%, moderate residual in 21%, and severe residual in 2%. Group I patients (n = 82, 64%) were operated on within 6 weeks of stroke and group II (n = 47, 36%) were operated on at varying times after 6 weeks. No significant difference was found in the incidence of cerebrovascular events (1.2% vs 4.2%) and deaths (1.3% vs 2.1%) between groups I and II with respect to the timing of carotid endarterectomy, and no significant difference was found between patients operated on at 2, 4, 6, or more than 6 weeks after stroke.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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We investigated the extent of induction in sublingual salivary gland cells apoptosis and tumor necrosis factor-α (TNF-α) expression with chronic ethanol ingestion. The experiments were conducted on rats pair-fed for 8 weeks with alcohol-containing and control liquid diet. The animals were killed, their sublingual glands dissected, and the glandular tissue used for quantitization of TNF-α expression and the assays of acinar cells apoptosis employing sandwich enzyme immunoassay for histone-associated DNA fragments. The mean value for TNF-α in sublingual gland of the control group was 22.3 pg/mg of protein and showed a 1.6-fold increase in the chronic ethanol diet group to 36.5 pg/mg of protein. In comparison with the controls, the sublingual gland of the chronic ethanol diet group also exhibited a 3.4-fold enhancement in acinar cell apoptosis. These findings suggest that chronic ethanol ingestion causes the enhancement in TNF-α expression and leads to the induction in salivary gland acinar cells apoptosis. Thus, the diminished secretion of saliva in alcoholics may be a direct result of increased salivary gland apoptosis.  相似文献   
10.
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
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