首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5108篇
  免费   229篇
  国内免费   28篇
耳鼻咽喉   166篇
儿科学   55篇
妇产科学   42篇
基础医学   600篇
口腔科学   160篇
临床医学   352篇
内科学   1155篇
皮肤病学   100篇
神经病学   374篇
特种医学   283篇
外科学   824篇
综合类   16篇
预防医学   184篇
眼科学   131篇
药学   282篇
中国医学   7篇
肿瘤学   634篇
  2023年   38篇
  2022年   48篇
  2021年   118篇
  2020年   67篇
  2019年   102篇
  2018年   107篇
  2017年   80篇
  2016年   107篇
  2015年   111篇
  2014年   156篇
  2013年   175篇
  2012年   319篇
  2011年   352篇
  2010年   174篇
  2009年   161篇
  2008年   317篇
  2007年   332篇
  2006年   400篇
  2005年   358篇
  2004年   372篇
  2003年   330篇
  2002年   322篇
  2001年   56篇
  2000年   58篇
  1999年   68篇
  1998年   64篇
  1997年   70篇
  1996年   57篇
  1995年   44篇
  1994年   60篇
  1993年   45篇
  1992年   43篇
  1991年   36篇
  1990年   31篇
  1989年   28篇
  1988年   17篇
  1987年   17篇
  1986年   17篇
  1985年   12篇
  1984年   21篇
  1983年   10篇
  1982年   9篇
  1981年   8篇
  1980年   9篇
  1979年   7篇
  1978年   6篇
  1976年   3篇
  1974年   3篇
  1969年   4篇
  1965年   2篇
排序方式: 共有5365条查询结果,搜索用时 265 毫秒
101.
Mondini dysplasia is rare, but has an important association with recurrent bacterial meningitis. We herein describe the case of a 3‐year‐old girl with unilateral sensorineural hearing loss who presented with three independent episodes of bacterial meningitis within 8 months. Temporal bone computed tomography indicated the characteristic features of Mondini dysplasia in the right inner ear. This was treated by surgical closure of the inner ear defect via oval window and additional vaccination was administered. Appropriate vaccination might prevent the recurrent bacterial meningitis associated with Mondini dysplasia.  相似文献   
102.
Granulocyte elastase released from activatedleukocytes plays an important role in leukocyteinfiltration. Since activated leukocytes have been shownto be involved in the pathogenesis of gastric mucosal lesion formation induced by nonsteroidalantiinflammatory drugs, inhibition of granulocyteelastase release from activated leukocytes may be usefulin the prevention of these lesions. Rebamipide, a novel antiulcer agent, inhibited granulocyte elastaserelease from activated neutrophils in vitro. Rebamipideand ONO-5046, a granulocyte elastase inhibitor, markedlyinhibited gastric mucosal lesion formation in rats. Gastric myeloperoxidase activity wassignificantly increased 3 hr after indomethacinadministration. This increase was significantlyinhibited by rebamipide and ONO-5046. Cimetidine did notinhibit granulocyte elastase release from activatedneutrophils. Although cimetidine markedly prevented theindomethacin-induced gastric mucosal lesion formation,it did not reduce the gastric myeloperoxidase activity. Therefore, unlike cimetidine, rebamipide mayprevent indomethacin-induced gastric mucosal lesionformation by inhibiting neutrophil activation.  相似文献   
103.
We report a 59-year-old man with chronic myelogenous leukemia (CML) in chronic phase who presented with a large abdominal tumor. Biopsy revealed proliferation of granulocytic-, erythroid-, and megakaryocytic-lineage cells in a retroperitoneal lymph node. The BCR/ABL fusion gene was detected on a paraffin-embedded tissue section of the lymph node by double-color fluorescence in situ hybridization, indicating an extramedullary hematopoietic tumor of CML origin. This patient has achieved a complete cytogenetic response for 19 months with imatinib mesylate (STI571; Gleevec), in association with the regression of the tumor. However, the development of an extramedullary tumor in chronic-phase CML generally indicates a poor prognosis, because it commonly consists of blast proliferation and is followed by blast crisis in the marrow within a few months. This case, therefore, points to the importance of histological examination of extramedullary tumors in CML for evaluation of disease status and for therapeutic decisions.  相似文献   
104.
For patients with a history of heparin-induced thrombocytopenia (HIT) who undergo cardiac or vascular surgery, the optimal anticoagulation substitute for heparin has yet to be established. Recombinant hirudin has been recommended; however, this agent is unsuitable for patients with renal dysfunction. Argatroban was used in the present patient who had a history of HIT and renal dysfunction and required peripheral vascular surgery. Argatroban was easy to monitor and control, regardless of renal function, and has advantages over other anticoagulants for such patients.  相似文献   
105.

Introduction

Bariatric surgery is recognized as an effective treatment for type 2 diabetes mellitus, but data on its efficacy for type 1 diabetes mellitus, especially slowly progressive insulin‐dependent diabetes mellitus, are limited.

Methods

We investigated five Japanese patients with slowly progressive insulin‐dependent diabetes mellitus who underwent bariatric surgery at our center.

Results

Five morbidly obese glutamic acid decarboxylase antibody‐positive diabetic patients underwent two different types of bariatric surgery. The mean titer of anti‐glutamic acid decarboxylase antibody was 4.6 U/mL, and the mean preoperative bodyweight and BMI were 113 kg and 39.6 kg/m2, respectively. The mean hemoglobin A1c was 8.4%. The mean fasting serum C‐peptide was 5.0 ng/mL. Laparoscopic sleeve gastrectomy was performed in two patients, while laparoscopic sleeve gastrectomy with duodenojejunal bypass was performed in three patients. At one year after surgery, the mean bodyweight and BMI significantly dropped, and the mean percentage of excess weight loss was 96.4%. The mean hemoglobin A1c was 5.7%. This favorable trend was maintained at mid‐term.

Conclusion

Bariatric surgery for morbidly obese patients with anti‐glutamic acid decarboxylase antibody–positive type 1 diabetes mellitus, especially slow progressive autoimmune diabetes, seemed effective in achieving mid‐term glycemic control. Longer follow‐up with a larger number of patients, as well as validation with more advanced patients with slowly progressive insulin‐dependent diabetes mellitus, will be needed.
  相似文献   
106.
107.
The patient was a 73-year-old man with a history of hypertension, diabetes mellitus, dyslipidemia, rheumatoid arthritis, repeated percutaneous coronary intervention and percutaneous peripheral intervention procedures. He was frequently admitted to our hospital for congestive heart failure with orthopnea. The myocardial washout rate of iodine-123-β-methyl iodophenyl-pentadecanoic acid was defective on scintigraphy. He was diagnosed with triglyceride deposit cardiomyovasculopathy (TGCV). Proton magnetic resonance spectroscopy (1H-MRS) indicated the level of myocardial triglyceride (TG) content to be extremely high (4.92%). This is the first report to confirm a massive accumulation of TG in the myocardium of a patient with TGCV using 1H-MRS noninvasively.  相似文献   
108.
Purpose

Sleep-disordered breathing is recognized as a comorbidity in patients with idiopathic pulmonary fibrosis (IPF). Among them, nocturnal hypoxemia has been reported to be associated with poor prognosis and disease progression. We developed a diagnostic algorithm to classify nocturnal desaturation from percutaneous oxygen saturation (SpO2) waveform patterns: sustained pattern, periodic pattern, and intermittent pattern. We then investigated the prevalence of nocturnal desaturation and the association between the waveform patterns of nocturnal desaturation and clinical findings of patients with IPF.

Methods

We prospectively enrolled patients with IPF from seven general hospitals between April 2017 and March 2020 and measured nocturnal SpO2 and nasal airflow by using a home sleep apnea test. An algorithm was used to classify the types of nocturnal desaturation. We evaluated the association between sleep or clinical parameters and each waveform pattern of nocturnal desaturation.

Results

Among 60 patients (47 men) who met the eligibility criteria, there were 3 cases with the sustained pattern, 49 cases with the periodic pattern, and 41 cases with the intermittent pattern. Lowest SpO2 during sleep and total sleep time spent with SpO2?<?90% were associated with the sustained pattern, and apnea–hypopnea index was associated with the intermittent pattern.

Conclusion

We demonstrated the prevalence of each waveform and association between each waveform and sleep parameters in patients with IPF. This classification algorithm may be useful to predict the degree of hypoxemia or the complication of obstructive sleep apnea.

  相似文献   
109.
Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) ( n  = 26), nodular (N) ( n  = 11), D + N ( n  = 13) or normal (n) ( n  = 11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis.  相似文献   
110.
BACKGROUND: Dietary fish oil potentiates the susceptibility of cellular membranes to lipid peroxidation, although it is also known to have beneficial effects on the development of cardiovascular diseases. OBJECTIVE: The effects of dietary fish oil against doxorubicin-induced cardiomyopathy, in which free radicals and lipid peroxidation are involved, were investigated in rats. ANIMALS AND METHODS: Sprague-Dawley rats (100 g) were fed a standard diet or a high fish oil diet (containing 10% fish oil) throughout the experimental period. Four weeks after starting each diet, experimental rats were treated with doxorubicin (cumulative dose 15 mg/kg) or vehicle (0.28 M dextrose solution). After three weeks of doxorubicin treatment, the cardiac performance, myocardial lipid peroxidation and myocardial vitamin E level were assessed. RESULTS: Compared with control rats, doxorubicin-treated rats showed a significantly increased mortality rate (P<0.05), and significantly decreased systolic blood pressure and left ventricular fractional shortening (P<0.01). The myocardial thiobarbituric acid-reactive substance level was significantly higher in doxorubicin-treated rats than in control rats (P<0.01), while the myocardial vitamin E level was significantly lower (P<0.05). Dietary fish oil enhanced the myocardial lipid peroxidation caused by doxorubicin, which was associated with a further decrease in myocardial vitamin E level. As a result, the rats treated with both doxorubicin and the high fish oil diet showed the highest mortality rate and the lowest cardiac performance of all the experimental groups. CONCLUSIONS: Dietary fish oil may reduce antioxidant defences and accelerate susceptibility of the myocardium to lipid peroxidation in rats under doxorubicin treatment. This may partly explain why dietary fish oil does not prevent doxorubicin-induced cardiomyopathy.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号