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   3636篇
  免费   231篇
  国内免费   18篇
耳鼻咽喉   50篇
儿科学   89篇
妇产科学   53篇
基础医学   475篇
口腔科学   340篇
临床医学   294篇
内科学   730篇
皮肤病学   67篇
神经病学   202篇
特种医学   246篇
外科学   317篇
综合类   55篇
一般理论   1篇
预防医学   471篇
眼科学   124篇
药学   235篇
  1篇
中国医学   34篇
肿瘤学   101篇
  2023年   22篇
  2022年   58篇
  2021年   143篇
  2020年   78篇
  2019年   99篇
  2018年   129篇
  2017年   83篇
  2016年   76篇
  2015年   111篇
  2014年   129篇
  2013年   166篇
  2012年   273篇
  2011年   255篇
  2010年   156篇
  2009年   119篇
  2008年   171篇
  2007年   215篇
  2006年   164篇
  2005年   161篇
  2004年   133篇
  2003年   126篇
  2002年   96篇
  2001年   79篇
  2000年   68篇
  1999年   65篇
  1998年   43篇
  1997年   36篇
  1996年   33篇
  1995年   31篇
  1994年   27篇
  1993年   46篇
  1992年   32篇
  1991年   31篇
  1990年   26篇
  1989年   52篇
  1988年   47篇
  1987年   60篇
  1986年   38篇
  1985年   47篇
  1984年   22篇
  1983年   18篇
  1982年   8篇
  1981年   14篇
  1980年   18篇
  1978年   11篇
  1977年   8篇
  1975年   6篇
  1973年   8篇
  1971年   7篇
  1967年   7篇
排序方式: 共有3885条查询结果,搜索用时 15 毫秒
1.
2.
3.
BackgroundTIAregistry.org is an international cohort of patients with transient ischemic attack (TIA) or minor stroke within 7 days before enrollment in the registry. Main analyses of 1-year follow-up data have been reported.5 We conducted subanalysis on the baseline and 1-year follow-up data of Japanese patients.MethodsThe patients were classified into 2 groups based on Japanese ethnicity, Japanese (345) and non-Japanese (3238), and their baseline data and 1-year event rates were compared. We also determined risk factors and predictors of 1-year stroke.ResultsCurrent smoking, regular alcohol drinking, intracranial arterial stenosis, and small vessel occlusion; and hypertension, dyslipidemia, coronary artery disease, and extracranial arterial stenosis were more and less common among Japanese patients, respectively. Stroke risk was higher and TIA risk was lower at 1-year follow-up among Japanese patients. The baseline risk factors for recurrent stroke were diabetes, alcohol drinking, and large artery atherosclerosis. Independent predictors of 1-year stroke risk were prior congestive heart failure and alcohol consumption.ConclusionsThe two populations of patients featured differences in risk factors, stroke subtypes, and outcome events. Predictors of recurrent stroke among Japanese patients included congestive heart failure and regular alcohol drinking. Strategies to attenuate residual risk of stroke aside from adherence to current guidelines should take our Japanese-patient specific findings into account.  相似文献   
4.
L1 disease is the most common genetic cause of congenital hydrocephalus. Mutations in the L1CAM gene are associated with an overlapping clinical spectrum of four X-linked neurological conditions, characterized by hydrocephalus, mental retardation, lower limb spasticity and adducted thumbs. Brain anomalies are frequently present in L1 disease. We describe these anomalies by reporting a case of a male newborn presenting with congenital hydrocephalus along with corpus callosum agenesis and enlargement of the massa intermedia. These findings, in association with the presence of clasped thumbs, raised the suspicion of L1 disease, which was confirmed by the detection of a mutation in the L1CAM gene. In cases of congenital hydrocephalus, recognition of the brain anomalies associated with L1 disease may contribute to pursuing the genetic analysis needed for the diagnosis and genetic counseling.  相似文献   
5.
Five years after treatment in a controlled trial, in which all had received self-exposure homework, a group of 40 agoraphobic outpatients retained marked improvement in agoraphobia, mood, and free-floating anxiety. Frequency of spontaneous panics decreased as much in those who had placebo and self-exposure as in those who received imipramine and self-exposure. Few patients, however, were completely well at 5 years and over half had received further treatment for agoraphobia during the follow-up. Patients who were still highly phobic at the end of the clinical trial were more often prescribed psychotropic medication during follow-up and remained phobic at 5 years. Phobic improvement had generalized more in those patients with very low than in those with moderate pretreatment Hamilton depression scores. Frequency of initial spontaneous panics did not predict outcome. Improvement in agoraphobia was associated with improved marital adjustment. Those who began with the best marital, work, and social adjustment were more improved in their phobias 5 years later.  相似文献   
6.
7.
Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP.  相似文献   
8.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
We report the case of a 75-year-old-woman who presented with bilateral scalp ulcerations and blindness, accompanied by severe headache and scalp tenderness, due to bilateral temporal arteritis without systemic involvement. A biopsy taken from the border of an ulceration showed evidence of giant cell arteritis. She was treated with oral prednisone, 60 mg per day. The ulcerations healed in a few weeks but the vision loss was irreversible. This case highlights for temporal arteritis the importance of accurate and timely diagnosis as well as the need for prompt therapy with systemic steroids in order to avoid major complications, namely loss of vision. It also demonstrates that scalp necrosis and ulcerations are skin signs associated with a poor prognosis.  相似文献   
10.
Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology.  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