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51.
In humans, intermittent and continuous theta‐burst stimulation (iTBS and cTBS) elicit long‐term changes in motor‐evoked potentials (MEPs) reflecting long‐term potentiation (LTP)‐ and depression (LTD)‐like plasticity in the primary motor cortex (M1). In this study, we used TBS to investigate M1 plasticity in patients with MSA. We also assessed whether responses to TBS reflect M1 excitability as tested by short‐interval intracortical inhibition (SICI), intracortical facilitation (ICF), short‐interval intracortical facilitation (SICF), and the input/output curves. We studied 20 patients with MSA and 20 healthy subjects (HS). Patients were clinically evaluated with the Unified Multiple System Atrophy Rating Scale. The left M1 was conditioned with TBS. Twenty MEPs were recorded from the right first dorsal interosseous muscle before TBS and 5, 15, and 30 minutes thereafter. In a subgroup of 10 patients, we also tested MEPs elicited by SICI, ICF, SICF, and input/output curves, before TBS. Between‐group analysis of variance showed that at all time points after iTBS MEPs increased, whereas after cTBS they decreased only in HS. In both subgroups tested, patients with predominant parkinsonian and cerebellar features, iTBS and cTBS left MEPs unchanged. MSA patients had reduced SICI, but normal ICF, SICF, and input/output curves. No correlation was found between patients' clinical features and responses to TBS and M1 excitability variables. These findings suggest impaired M1 plasticity in MSA. © 2013 International Parkinson and Movement Disorder Society  相似文献   
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BACKGROUND/AIMS: We investigated whether increasing the efferent vagal activity by insulin-induced hypoglycemia would enhance gastric emptying and volumes in healthy subjects. METHODS: Twenty healthy volunteers (10 males) were examined with and without vagal stimulation by insulin-induced hypoglycemia using a glucose clamp technique. Stomach function was tested by drinking meat soup (0.04 kcal ml(-1)) at a rate of 100 ml min(-1) until maximal capacity. Intragastric volume at maximal drinking capacity was determined by three-dimensional ultrasound. Respiratory sinus arrhythmia (RSA) was used as an index of cardiac vagal activity and plasma pancreatic polypeptide (PP) as a measure of gastric vagal activity, and skin conductance (SC) as a measure of sympathetic tone. RESULTS: Insulin-induced hypoglycaemia increased drinking capacity (p = 0.002), gastric emptying (p = 0.02), PP (p = 0.004) and SC (p = 0.004), while intragastric volume was unchanged (p = 0.7) and RSA decreased (p = 0.03). CONCLUSION: Enhancement of gastric vagal activity by insulin-induced hypoglycemia increased drinking capacity and gastric emptying similarly, resulting in an unchanged intragastric volume. Enhanced efferent vagal activity to the stomach (as measured by PP) was not associated by enhanced cardiac vagal activity (as measured by RSA), possibly a consequence of stress-induced sympathetic activation during the procedure.  相似文献   
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BACKGROUND/AIMS: Previous reports state that there is absorption of bismuth through active peptic ulcers. It was therefore of interest to investigate the extent of absorption in patients at the ulcer and post-ulcer stages. METHODOLOGY: Twenty H. pylori-positive patients with gastroscopically verified gastric or duodenal ulcers were randomly allocated to ingest 3000 mg bismuth subnitrate (BSN) (10 patients) or 480 mg colloidal bismuth subcitrate (CBS) (10 patients). Bismuth serum concentration in 12 samples drawn during the first 4 hours after drug intake was analyzed and the area under the curve (Bi-AUC) was calculated. Anti-H. pylori therapy with amoxicillin and lanzoprazole eradicated H. pylori in 10 patients and healed the ulcers in all patients 4 weeks after therapy ended, then the bismuth absorption test was repeated. RESULTS: There was no significant difference between ulcer- and post-ulcer Bi-AUC for patients receiving BSN or for patients receiving CBS. On a molar basis, CBS gave a 17.4-fold greater absorption of bismuth compared to BSN. CONCLUSIONS: The presence of an active ulcer does not significantly influence the absorption of bismuth from CBS or BSN.  相似文献   
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The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.  相似文献   
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Mark AK  高立  杨敏洁 《放射学实践》2006,21(12):1292-1295
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,…  相似文献   
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BACKGROUND: It is well documented that dyspepsia in patients with peptic ulcer disease (PUD) improves markedly after eradication of Helicobacter pylori, while rarely does it improve in patients with functional dyspepsia. There is a large group of H. pylori-infected patients who do not qualify for either diagnosis, but in whom eradication may be considered. The aim of this study was to compare symptom severity, change in gastrointestinal symptoms 1 year after eradication and satisfaction with therapy between PUD patients and patients with endoscopic diagnoses of gastritis and/or duodenitis (G/D patients). METHODS: The patients were randomized to one of four triple regimens containing ranitidine bismuth and metronidazole, and either oxytetracycline or spiramycine. Eradication was assessed with the 14C-urea breath test. GI symptoms were evaluated using the Gastrointestinal Symptom Rating Scale (GSRS) and the Ulcer Esophagitis Subjective Symptoms Scale (UESS) questionnaires. RESULTS: One-hundred-and-eighty-three patients were recruited from GI outpatient clinics. Patients with PUD and G/D had similar severity of symptoms before eradication therapy. One year after H. pylori eradication, 99% of the PUD patients and 75% of the G/D patients felt better regarding their main upper GI complaint. Abdominal pain score decreased by 48% as measured by GSRS and by 78% as measured by UESS in the PUD group and by 25% and 47%, respectively, in the G/D group. Reflux symptoms decreased by 41% and 63% in PUD patients and by 28% and 45% in G/D patients; indigestion by 30% and 47% in PUD and by 20% and 34% in G/D; eating discomfort by 60% in PUD and by 35% in G/D. Sleep quality score improved by 68% in PUD and by 41% in NU patients. Constipation decreased by 22% in the PUD group. All these differences in symptoms were highly significant compared to baseline. Diarrhoea was unchanged. CONCLUSIONS: Abdominal pain, reflux symptoms, indigestion and the ability to eat and sleep improved in both PUD and G/D patients 1 year after H. pylori eradication. Chronic diarrhoea was not induced. Abdominal pain improved significantly more in PUD than in G/D patients. Further study of the effect of H.pylori eradication in G/D patients is warranted.  相似文献   
60.
Objective : To evaluate the efficacy of biliary‐enteric bypass in the palliation of malignant hilar biliary obstruction. Materials and Methods : Records of 19 patients from 1995 to 1998 were reviewed. There were 13 patients with cholangiocarcinoma and 6 patients with carcinoma of the gallbladder. Single biliary‐enteric bypass had been performed in 13 of the patients; the rest had more than one biliary‐enteric anastomosis. Results : The 30‐day mortality was 21% (4/19 patients). Bile leakage occurred in 2 patients, leading, in both, to fatality. Excluding the 30‐day mortality, the median survival of patients with carcinoma of the gallbladder and cholangiocarcinoma was 116 days (43–200) and 202 days (47–1207), respectively. The mean hospital stay was 31 days (13–59) and all patients were discharged with their symptoms relieved and a drop in bilirubin of at least two‐thirds their pre‐operative level. The late complication rate was 26.7% (4/15 patients). Conclusion : Biliary‐enteric bypass is effective in the palliation of symptoms of patients suffering from unresectable hilar biliary obstruction, although it carries considerable mortality and morbidity. Stenting, rather than surgery, should be considered for patients with unresectable gallbladder cancer.   相似文献   
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