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1.
Electrocardiograms were evaluated in 39 children and adolescents before and after the clinical use of imipramine and desipramine. The average increase in PR interval was 0.01 seconds. The PR interval increased by 0.02 seconds in 11 subjects, and a new first-degree atrioventricular block developed in two subjects. These changes were not related to the choice between imipramine and desipramine, the dose, or the method of administration. An increase in PR interval by 0.02 seconds or more did correlate with having an abnormality disclosed on a pretreatment electrocardiogram. The average increase in PR interval was 0.007 seconds for subjects with normal baseline electrocardiograms and 0.019 seconds for subjects with conduction and nonconduction abnormalities disclosed in baseline tracings. None of the electrocardiogram changes resulted in adverse clinical consequences.  相似文献   
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Pre-clinical psychiatric emergency situations (PES) have been identified to be the third major reason for emergency physician (EP) calls with a frequency of approximately 10%. Until now, there are no investigations about regional differences between urban and rural regions in frequencies, diagnoses, or treatment necessities of PES. A retrospective analysis of all anonymised EP protocols of one year in a metropolitan (Hamburg) and a rural region (Schaumburg County) was performed with the same methodological approach. In both regions, the frequency of PES was revealed to be near 10%. Gender and age of psychiatric patients as well as reasons for calls were comparable. In Schaumburg County, much less disturbances due to illegal drugs were observed. However, more patients had to be treated because of suicide attempts and alcoholism. All in all, disturbances seemed less life-threatening than in the metropolitan region. In conclusion, frequency and kind of PES do not differ substantially between rural and urban regions. Considering the prevalence of PES, the particularities in diagnosis and treatment and the dissipation of institutionalised psychiatric care mainly in rural regions, more training in psychiatric subjects is needed.  相似文献   
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Anastomotic leaks are still among the most common severe postoperative complications and account for the majority of postoperative deaths after esophagectomy and gastrectomy. Every disturbance of the normal postoperative course should trigger surgeons to consider an underlying anastomotic leak and initiate a specific diagnostic workup. This includes direct endoscopic inspection of the anastomosis to evaluate the vitality of the anastomosed organs and the size of the leak. Adequate external drainage of the leak and prevention of further contamination are the primary therapeutic goals. Selection of therapy is guided by the available modalities for sufficiently draining the leak and avoiding sepsis. The spectrum of therapeutic options ranges from simple opening of the neck incision in cervical esophageal anastomoses, interventional placement of drains, to endoscopic intervention with closure of the fistula or placement of stents, and reoperation with exclusion, diversion, or discontinuity resection.  相似文献   
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Fluorescent tracers are commonly used in fluorophotometric studies of ocular fluids and tissues that contain background protein. Background-protein concentrations were found to decrease or increase significantly the measure of fluorescence emitted from solutions containing sodium fluorescein, fluorescein-labeled dextran, or fluorescein-labeled horseradish peroxidase. The effect of background protein on fluorescence was expressed as a function of the specific fluorescent tracer, tracer concentration, and background-protein concentration; it can be corrected in the analysis of fluorophotometric data. Fluorophotometric studies--particularly those in which the background-protein level is expected to be abnormally high, such as postoperative and pathologic studies--may need to include either a data correction based on measured effects of background protein on tracer fluorescence or, in the case of clinical investigations, recognize at least the potential for a range of possible interpretations.  相似文献   
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To assess the effect of levodopa on distinct freezing of gait (FOG) subtypes in patients with 'off' FOG. Nineteen patients (12 men, mean age 62.0 +/- 8.4 years) with Parkinson's disease and clinically significant FOG during 'off' states were videotaped whilst walking 130 m during 'off' and 'on' states. Three independent observers characterized the type, duration, and clinical manifestations and quantified FOG by analyzing the videotapes. Their combined mean scores were used for statistical analysis. The intra-class correlation coefficient assessed inter-observer reliability. Wilcoxon and Friedman tests evaluated differences in mean frequencies of FOG characteristics. During 'off' states, FOG was elicited by turns (63%), starts (23%), walking through narrow spaces (12%) and reaching destinations (9%). These respective values were only 14, 4, 2 and 1% during 'on' states (P < 0.011). Moving forward with very small steps and leg trembling in place were the most common manifestations of FOG; total akinesia was rare. Most FOG episodes took <10 s and tended to be shorter during 'on' states. Levodopa significantly decreased FOG frequency (P < 0.0001) and the number of episodes with akinesia (P < 0.001). Distinction amongst FOG subtypes enables evaluation of distinctive therapeutic response. Levodopa helps in reducing the frequency and duration of 'off'-related FOG.  相似文献   
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To enable an image understanding system to provide an automated interpretation of diagnostic imagery it must have access to all of the concepts, procedures and methods used by human experts. The paper describes information elicitation from experts of different domains and the construction of a knowledge file. Uncertainty management is based on Bayesian belief network methods.  相似文献   
9.
 Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis. PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus. PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC (day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion, corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly were excluded from the study. Mean platelet content of the PC was 262×109 for BC-PC and 251×109 for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient platelet increment even when stored for up to 5 days. Received: 28 December 1995 / Accepted: 14 May 1996  相似文献   
10.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
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