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   2250篇
  免费   186篇
  国内免费   5篇
耳鼻咽喉   16篇
儿科学   120篇
妇产科学   48篇
基础医学   231篇
口腔科学   31篇
临床医学   395篇
内科学   377篇
皮肤病学   14篇
神经病学   143篇
特种医学   361篇
外科学   258篇
综合类   70篇
一般理论   2篇
预防医学   154篇
眼科学   15篇
药学   132篇
  1篇
中国医学   9篇
肿瘤学   64篇
  2021年   21篇
  2020年   18篇
  2019年   17篇
  2018年   30篇
  2017年   17篇
  2016年   23篇
  2015年   30篇
  2014年   38篇
  2013年   53篇
  2012年   86篇
  2011年   79篇
  2010年   80篇
  2009年   46篇
  2008年   96篇
  2007年   93篇
  2006年   100篇
  2005年   100篇
  2004年   89篇
  2003年   75篇
  2002年   76篇
  2001年   64篇
  2000年   62篇
  1999年   60篇
  1998年   52篇
  1997年   54篇
  1996年   44篇
  1995年   61篇
  1994年   51篇
  1993年   51篇
  1992年   42篇
  1991年   34篇
  1990年   42篇
  1989年   81篇
  1988年   50篇
  1987年   55篇
  1986年   62篇
  1985年   46篇
  1984年   29篇
  1983年   29篇
  1982年   26篇
  1981年   31篇
  1980年   28篇
  1979年   18篇
  1978年   27篇
  1977年   22篇
  1976年   22篇
  1975年   17篇
  1973年   16篇
  1972年   10篇
  1969年   13篇
排序方式: 共有2441条查询结果,搜索用时 31 毫秒
1.
2.
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics.  相似文献   
3.
Functional Outcome After Surgical Treatment of Esophageal Perforation   总被引:1,自引:0,他引:1  
Background. The functional results after treatment of intrathoracic esophageal perforations have been poorly documented.

Methods. A retrospective review of 42 patients who underwent treatment of intrathoracic esophageal perforation associated with benign esophageal disease was performed.

Results. Of 42 patients treated for esophageal perforation, 25 underwent primary repair, 15 underwent esophagectomy and reconstruction, 1 underwent cervical esophagostomy and drainage followed by esophageal resection, and 1 had drainage alone followed by primary repair. Among the patients treated with primary repair, at least one additional operation was required in 13 patients. Of the 15 patients treated with esophagectomy and reconstruction, none required further operative treatment. Follow-up averaged 3.7 years, and of the 36 survivors available for follow-up, 18 (50%) required at least one esophageal dilation postoperatively, and 3 (8.3%) have required regular dilations. Subjectively, 19 of 36 patients (53%) indicate that their swallowing is better than before perforation, it was the same in 12 (33%), and worse in 4 (11%).

Conclusions. In conclusion, approximately one third of patients surviving primary repair of esophageal perforations have continued difficulty with swallowing, which often requires esophageal dilations or esophageal reconstructive procedures, or a combination of both. Optimal long-term results are achieved when primary repair is performed in patients with motor disorders or a “normal” esophagus. Esophagectomy is a better option in those patients with strictures or diffuse esophageal disease.  相似文献   

4.
5.
6.
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients.  相似文献   
7.
8.
Nephrocalcinosis (NC) detected by ultrasound is a recognized abnormality for some patients with X-linked hypophosphatemia (XLH) who received vitamin D2 and inorganic phosphate therapy, but is commonly observed in XLH patients treated with 1,25-dihydroxyvitamin D3 and inorganic phosphate supplementation. Nevertheless, long-term follow-up of kidney function in XLH patients with NC detected ultrasonographically has not been reported. We investigated two women with XLH, ages 31 (patient 1) and 39 (patient 2) years, each of whom had suffered at least one documented episode of vitamin D2-induced hypercalcemia and renal azotemia during childhood. Patient 2 had also been treated with inorganic phosphate. No medications for XLH had been taken during adulthood. Renal ultrasonography at our institution demonstrated marked bilateral medullary NC in both women. No other explanation was found for their NC that apparently occurred several decades earlier from medical therapy for XLH. Detailed studies (including creatinine clearance, β2-microglobulin excretion, and fasting urinary osmolality and acidification) revealed no impairment of kidney function in either patient. Our findings indicate that subradiographic medullary NC acquired during medical therapy for XLH may persist for decades, but with no adverse renal sequelae. Definitive (long-term) assessment of kidney function in the XLH population with NC, however, will be necessary to fully understand the risk of current medical treatment for this most common heritable form of rickets.  相似文献   
9.
The chief instigator of offshore stress is time which in oil parlance is money, writes Patrick Whyte, an offshore medical officer. He explains that medical personnel by showing that they practice a healthy lifestyle on the offshore oil rigs can set a practical example of coping with the stressful conditions.  相似文献   
10.
We studied prospectively 49 patients being treated in an intensive care unit with aminoglycosides for gram-negative sepsis. Pharmacokinetic data were calculated from three post-dose serum levels using a one-compartment model. Doses required to achieve peak levels between 5 and 10 mg/l with trough levels approximately 1.0 mg/l ranged between 2 and 12 mg/kg per day (mean dose 7 mg/kg per day). During therapy 60% of the patients had a change in their apparent volume of distribution (Vd) of greater than 20%. These patients were likely to have confirmed infection and to be febrile at the start of treatment. Two to three weeks after discharge ten patients were restudied after a single dose of aminoglycoside. There was a reduction in mean Vd from 0.24 to 0.18 l/kg (P less than 0.02). Critically ill patients have significantly larger volumes of distribution and may require larger doses per kilogram of body weight of aminoglycoside to achieve therapeutic concentrations. Due to considerable variation in kinetic parameters, the use of standard doses or dosing nomograms is not recommended.  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