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991.
本文报告了黄夹甙、次甙甲和次甙乙对麻醉犬的血流动力学和器官血流量的作用,比较了黄夹甙成分和洋地黄制剂对实验性心力衰竭猫和豚鼠的强心效力和安全范围。结果表明,这些强心甙均有正性肌力作用,次甙乙收缩血管的作用不明显。以心力衰竭豚鼠治疗量为指标,强心作用顺序为黄夹次甙甲>次甙乙>黄夹甙>西地兰>地高辛。次甙甲的安全范围比洋地黄制剂大。用放射免疫法测定了心衰豚鼠静脉滴注黄夹甙、次甙甲和次甙乙达到治疗效力、中毒反应(心律失常)和死亡时的血药浓度,表明次甙甲的治疗和中毒浓度交叉很小。黄夹甙、次甙甲和次甙乙口服吸收快,生物利用度相似,次甙甲消除快(T 1/2 2.13 h,次甙乙除消较慢(T 1/2 6.79)。  相似文献   
992.
Industrialization and urbanization have changed the structure of Taiwanese families. Placing elder family members with impairments in nursing homes has become a new caregiving alternative. However, Taiwanese commonly consider this placement to be a violation of traditional filial obligation. Therefore, institutionalization is a highly sensitive cultural issue. Data were gathered through semi-structured interviews with nine family members, revealing three major processes in the decision of institutionalization -- breaking harmony, rebuilding harmony and evolution, as well as four important factors that influence the decision -- the quality of the relationship between the elder and his/her family, characteristics of the elder, financial condition of the family and perceived public opinion toward institutionalization. The findings suggest that the decision process in institutionalization is a gradual, fluid, cyclical movement without definite steps.  相似文献   
993.
近年来由于训练强度不断增大,高水平运动员心律失常的发生率显著增加。本文研究资料表明,男心律失常组安静时心搏量明显大于正常组(P<0.05),而运动后心搏量降低(正常组心搏量增加),说明心律失常的运动员心脏储备能力差,心脏泵血功能降低,应予慎重对待。  相似文献   
994.
Ten adult male volunteers were studied to examine the effect on plasma beta-endorphin (B-EN) of bicycling and running for 1 h at 60% VO2max. All subjects were physically active and accustomed to both exercise modes (mean VO2max in ml X kg-1 X min-1; bicycling, 54; running, 59). Following preliminary VO2max tests, subjects participated in randomly ordered experimental sessions of bicycling and running for 1 h at loads requiring 60% of their mode-specific VO2max. Five subjects also participated in control sessions. Blood samples were collected immediately pre- and immediately post-exercise, and hematocrits were determined. Samples were centrifuged, separated, and plasma was stored at -50 degrees C until analysis for B-EN. Analysis involved separation of B-EN from beta-lipotropin by short column chromatography followed by radioimmunoassay. Despite an observed trend for elevated B-EN following exercise, there were no significant pre- to post-exercise differences (P greater than 0.05) in mean B-EN levels in any of the three sessions. Expressed as percentage change in B-EN, there were no significant differences between bicycling, running, or control. These results indicate that 1 h bicycling or running exercise at 60% VO2max does not consistently increase B-EN, and that responses are variable between individuals.  相似文献   
995.
Visualization of suppressed thyroid tissue by Tc-99m MIBI.   总被引:3,自引:0,他引:3  
The authors describe a case of suppressed normal thyroid tissue in a patient with autonomous toxic nodule, which was visualized by a Tc-99m MIBI thyroid scan without thyrotropin (TSH) stimulation. The findings suggest that Tc-99m MIBI can be a substitute for conventional thyroid imaging using I-131 to visualize suppressed normal thyroid tissue without TSH stimulation and its side effects.  相似文献   
996.
Pancreatic transplant imaging   总被引:1,自引:0,他引:1  
Forty-four clinical episodes of suspected (pancreas) transplant rejection in 17 pancreatic transplantation patients were reviewed retrospectively. The clinical impression of acute graft rejection, chronic rejection, or nonrejection in each episode was correlated with the results of 19 nuclear medicine, 12 ultrasound (US), and 44 magnetic resonance (MR) imaging studies. US was found to be a moderately sensitive (82%) method of detecting graft rejection. US also was effective in identifying intra- and peripancreatic fluid accumulations. Nuclear medicine imaging was also a sensitive technique (86%) and the only modality that provided physiologic information regarding graft perfusion. MR imaging allowed correct prediction of the presence or absence of graft rejection in 39 of 44 cases (sensitivity, 100%; specificity, 76%) and was an effective means of detecting pathologic fluid collections. Nuclear medicine, US, and MR imaging are all believed to be sensitive methods of detecting graft rejection and are complementary adjuncts to the clinical evaluation of pancreatic transplants.  相似文献   
997.
ObjectiveWe retrospectively investigate the prevalence of gynecomastia as false-positive 2-[18F]fluoro-2-deoxy-d-glucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) imaging in patients with hepatocellular carcinoma (HCC).MethodsAmong the 127 male HCC patients who underwent 18F-FDG PET/CT scan, the 18FDG uptakes at the bilateral breasts in 9 patients with gynecomastia were recorded as standard uptake value (SUVmax) and the visual interpretation in both early and delayed images.ResultsThe mean early SUVmax was 1.58/1.57 (right/left breast) in nine gynecomastia patients. The three patients with early visual score of 3 had higher early SUVmaxs.ConclusionGynecomastia is a possible cause of false-positive uptake on 18F-FDG PET/CT images.  相似文献   
998.
Kao PC  Ferris DP 《Gait & posture》2009,29(2):230-236
A robotic ankle-foot orthosis (AFO) that provides powered assistance could adjust to varying gait dynamics much better than a rigid AFO. To provide insight into how humans would adapt to a powered AFO, we studied the response of neurologically intact subjects walking with an active dorsiflexion assist orthosis proportionally controlled by tibialis anterior electromyography (EMG). We examined the two mechanical functions of ankle dorsiflexors in gait (power absorption at heel strike and power generation at toe-off) by recruiting two groups of healthy subjects: Group One, called Continuous Control (n=5), had dorsiflexion assistance both at the initial heel contact and during swing; Group Two, called Swing Control (n=5), had the assistance only during swing. We hypothesized both groups of subjects would reduce tibialis anterior EMG amplitude with practice walking with the powered dorsiflexion assist. Ten healthy subjects were fitted with custom-made orthoses that included an artificial pneumatic muscle providing dorsiflexor torque. We collected lower body kinematics, EMG, and artificial muscle force while subjects walked on a treadmill for two 30-min training sessions. We found that subjects walked with increased ankle dorsiflexion by 9 degrees but showed different adaptation responses of the two tibialis anterior EMG bursts. The first EMG burst around heel strike had approximately 28% lower amplitudes (p<0.05) but the second EMG burst during swing had similar amplitudes. These results provide baseline data of EMG controlled dorsiflexion assist in neurologically intact humans that can be used to guide future studies on neurologically impaired individuals.  相似文献   
999.
PURPOSETo assess the role of regional cerebral blood flow measured by technetium-99m hexamethyl propyleneamine oxime (HMPAO) brain single-photon emission CT (SPECT) in viral encephalitis of children.METHODSEighteen children diagnosed as having viral encephalitis (12 Epstein-Barr virus, 4 herpes simplex virus, and 2 Japanese B virus) underwent Tc-99m HMPAO brain SPECT and brain MR and/or CT.RESULTSDuring the acute episode, 4 (22%) of the 18 patients had localized abnormality on brain MR and/or CT. Tc-99m HMPAO brain SPECT in the acute phase showed that 17 (94%) of the 18 patients had increased regional cerebral blood flow and 1 (6%) of the 18 children had a normal brain SPECT. Follow-up brain SPECT was performed at least 15 days after the acute episode. In 17 patients with abnormal first brain SPECT, 12 (71%) had normal second brain SPECT and 5 (29%) had decreased regional cerebral blood flow. The group of patients with normal regional cerebral blood flow on the follow-up brain SPECT had a better outcome than the group of patients with decreased regional cerebral blood flow.CONCLUSIONS(a) The Tc-99m HMPAO brain SPECT was abnormal more often than CT or MR in children with acute viral encephalitis and provided better location. (b) In acute episodes of encephalitis, most patients showed locally increased regional cerebral blood flow. (c) After acute episodes, the regional cerebral blood flow returned to normal in most cases. (d) A normal Tc-99m HMPAO brain SPECT in the subacute phase usually indicates a good clinical outcome (no neurologic defect) 1 year after the acute illness in children with viral encephalitis.  相似文献   
1000.
Intrathoracic coelomic cysts are benign embryonic tumors with a mesothelial lining. The aim of this work was to review possible localizations (pleuropericardic and other), the remaining surgical indications, and the current situation of minimally invasive techniques. We reviewed retrospectively, 28 cases of intrathoracic coelomic cysts in 12 men and 16 women, mean age 44 years. We recorded the cyst localization, clinical signs, indication for surgery, access routes used, and outcome. Twenty-one cysts were pleuropericardial cysts and 7 were ectopic mediastinal cysts. In all 7 of the ectopic mediastinal cysts and 4 of the pleuropericardial cysts surgery was indicated for diagnosis; for the other pleuropericardial cysts the indication was based on clinical signs (n = 4), large volume (n = 4), progressing volume (n = 7), no apparent reason (n = 1) and association with surgery for pneumothorax (n = 1). Assess was by mediastinoscopy (n = 1), mediastinotomy (n = 1), sub-xyphoid route (n = 1), thoracotomy (n = 18), and videothoracoscopy (n = 7). Long-term outcomes (mean follow-up 4 years 4 months) were good with no recurrences. Postoperative sequelae were observed in 6 cases after thoracotomy and in 1 case after videothoracoscopy. In summary, pleuropericardial cysts warrant surveillance without surgery unless their volume increases or clinical signs develop. Ectopic mediastinal cysts usually require surgery for diagnosis. It would appear advisable to prefer videothoracoscopy which allows diagnosis and excision of pleuropericardial cysts. Minimal thoracotomy may be helpful for ectopic mediastinal cysts.  相似文献   
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