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   1726篇
  免费   95篇
  国内免费   8篇
耳鼻咽喉   30篇
儿科学   25篇
妇产科学   30篇
基础医学   152篇
口腔科学   79篇
临床医学   115篇
内科学   349篇
皮肤病学   23篇
神经病学   200篇
特种医学   76篇
外科学   305篇
综合类   4篇
预防医学   29篇
眼科学   15篇
药学   211篇
中国医学   2篇
肿瘤学   184篇
  2023年   11篇
  2022年   8篇
  2021年   21篇
  2020年   9篇
  2019年   18篇
  2018年   33篇
  2017年   13篇
  2016年   23篇
  2015年   20篇
  2014年   39篇
  2013年   56篇
  2012年   74篇
  2011年   86篇
  2010年   57篇
  2009年   40篇
  2008年   66篇
  2007年   99篇
  2006年   78篇
  2005年   89篇
  2004年   56篇
  2003年   69篇
  2002年   89篇
  2001年   59篇
  2000年   59篇
  1999年   51篇
  1998年   21篇
  1997年   26篇
  1996年   19篇
  1995年   14篇
  1994年   9篇
  1993年   14篇
  1992年   78篇
  1991年   57篇
  1990年   63篇
  1989年   35篇
  1988年   42篇
  1987年   28篇
  1986年   31篇
  1985年   30篇
  1984年   21篇
  1983年   29篇
  1982年   5篇
  1981年   5篇
  1979年   11篇
  1978年   5篇
  1977年   6篇
  1975年   7篇
  1974年   6篇
  1973年   9篇
  1972年   8篇
排序方式: 共有1829条查询结果,搜索用时 15 毫秒
1.
We report the results and complications of 103 consecutive patients who underwent percutaneous removal of renal and ureteral stones. The overall clinical success rate was 80.6%. For the recent 33 cases in which UL-arm fluoroscopy was used, however, the success rate was as high as 87.9%, which was considered to be due to easier establishment of percutaneous direct access. The most common complications were bleeding (18.5%), extravasation (15.5%) and fever (9.7%). Four cases with significant bleeding required arteriography, but there were no sign of arteriovenous fistula nor pseudoaneurysms in any cases. To study renal parenchymal damage in the percutaneous procedures, plasma renin activities (PRA) were compared in 54 cases after six months. However, significant elevation of PRA did not occur in any case.  相似文献   
2.
3.
Y Tabuchi  H Deguchi  K Imanishi  Y Saitoh 《Cancer》1992,69(10):2411-2417
Correlations between preoperative carcinoembryonic antigen (CEA) levels of peripheral (p-CEA) and draining blood (d-CEA), the CEA gradient between d-CEA and p-CEA (d-p CEA gradient) levels, and survival after resection of cancer lesions were examined in 94 patients with colorectal cancer. Survival rates of patients with normal p-CEA and d-CEA levels and d-p CEA gradient levels (less than 5 ng/ml) were significantly better than those of patients with abnormal levels (greater than or equal to 5 ng/ml), and the 5-year survival rates were, respectively, 62%, 69%, and 72% in the former and 42%, 41%, and 35% in the latter. The differences in the 5-year survival rates between patients with normal and abnormal d-p CEA gradient, d-CEA, and p-CEA levels were 37%, 28%, and 20%, respectively. Furthermore, the positive rates of d-CEA levels (64%) and d-p CEA gradient levels (48%) were higher than that of p-CEA levels (36%). However, some significant differences in background variables also were found between the respective groups of patients with normal and abnormal p-CEA and d-CEA levels and d-p CEA gradient levels. These results suggest that patients with poor prognoses are examined more effectively by determining their d-p CEA gradient and d-CEA levels than their p-CEA levels, and that CEA may be expressed as a quantitative sum total of various pathophysiologic variables of patients with colorectal cancer but not as an independent prognostic variable.  相似文献   
4.
Antibacterial effects of combination use of arbekacin (ABK) with cefotiam (CTM) or cefuzonam (CZON) were evaluated against methicillin-resistant Staphylococcus aureus (MRSA) and the following results were obtained. 1. Antibacterial effects of combinations of ABK with CTM and with CZON were equally potent against MRSA at clinically expected 1 MIC of ABK in blood. However, at a sub MIC of ABK the different effects were observed between the 2 combinations. The antibacterial effect of the former was strong and that of the latter was a little weak. 2. In either combination the potency of the antibacterial activity was less dependent on the concentration of CTM or CZON, but was strongly dependent on ABK concentrations. These results suggest that antibacterial effects of the combinations were highly dependent on antibacterial potency and concentration of ABK as previously reported for combinations of ABK with other drugs. 3. The combination use of ABK with CTM appears to be useful in cases of infection by MRSA alone while the combination use of ABK with CZON appears to be useful in cases of double infection with MRSA and Gram-negative bacterium.  相似文献   
5.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
6.
The vascular type of Ehlers-Danlos syndrome is a genetic disorder of connective tissue and is frequently associated with catastrophic arterial complications. Its surgical treatment is extremely difficult because of the fragility of vessels. This article describes three patients with vascular type of Ehlers-Danlos syndrome who developed mesenteric hemorrhage due to spontaneous arterial rupture. The clinical and molecular characteristics of the disease are briefly reviewed.  相似文献   
7.
AIM OF THE STUDY: Although a bleeding tendency as a first symptom is a critical condition in congenital biliary dilatation (CBD), the clinical details of this symptom remain unclear. We assessed this condition in children with CBD in this paper. MATERIALS AND METHODS: Sixty-five children with CBD were treated at our institute between 1983 and 2004. The children, initially presenting with bleeding manifestations such as intracranial hemorrhage and bloody stools, were defined as the bleeding group, and the remaining children with digestive symptoms such as abdominal pain and vomiting were defined as the digestive group. The clinical features were compared between these two groups. RESULTS: In 6 of the 65 cases, bleeding manifestations were noted (9.2 %). All six had cystic-type choledochal dilatation. The mean age of the bleeding group was significantly younger than that of the digestive group, and bleeding was more frequent, especially in infants less than 12 months of age. In a laboratory study, the bleeding group showed a more prolonged blood coagulation time than the digestive group did. Serum amylase and lipase levels in the bleeding group were almost normal, while those in the digestive group were significantly higher. The direct bilirubin level in the bleeding group was significantly higher than that in the digestive group. CONCLUSIONS: Disturbed blood coagulation due to vitamin K deficiency related to cholestasis results in a bleeding tendency in children with CBD. Therefore, pediatric surgeons should be aware of this rare but critical condition which can be prevented by rapid and precise treatment with vitamin K supplementation.  相似文献   
8.
The transport of ebiratide, a novel adrenocorticotropic hormone (ACTH) analogue, [H-Met-(O2)-Glu-His-Phe-D-Lys-Phe-NH(CH2)8-NH2], through the blood-brain barrier was directly demonstrated in-vivo. [125I]Ebiratide (16.9 MBq mL-1) or [14C]sucrose (29.2 MBq mL-1) known to be restrictively transported through the blood-brain barrier was infused into the rat internal carotid artery at a flow rate of 50 microL min-1 for 10 min, and after 15 min infusion the distribution volume of each compound in the brain parenchyma was determined by the capillary depletion method. The distribution volume of [125I]ebiratide was 167.8 +/- 62.2 microL (g brain)-1, which was about seven times higher than that of [14C]sucrose (24.9 +/- 4.0 microL g brain)-1, indicating the uptake of ebiratide into brain parenchymal cells. During the infusion into the internal carotid artery, brain microdialysis was simultaneously performed to directly collect the brain interstitial fluid as the dialysate. Radioactivity was detected in the dialysate during the [125I]ebiratide infusion and HPLC analysis of the dialysate revealed that the intact ebiratide accounted for greater than or equal to 80% total radioactivity. The concentrations of [125I]ebiratide and [14C]sucrose in the brain interstitial fluid were estimated based on the relative recovery obtained in the in-vitro recovery study. The brain interstitial fluid/internal carotid arterial blood concentration ratio for [125I]ebiratide was determined to be 1.47 x 10(-2) +/- 0.17 x 10(-2) and was about eight times higher than that for [14C]sucrose (1.92 x 10(-3) +/- 0.36 x 10(-3)), indicating significant transport of ebiratide to the brain interstitial fluid.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
Of 119 patients with surgical correction of anorectal malformations, 47 who were 10-30 years of age were interviewed personally and had manometric studies to evaluate postoperative continence. This clinical study included not only long-term anorectal function but also sexual function. Patients with low type anomalies or with intermediate type anomalies were more likely to be continent, whereas patients with high type lesions had some problems with continence. However, only two of the 16 patients (12%) with high type anomalies were classified as having poor results. This rate is perhaps lower than might be expected. Thus, incontinent patients may become continent even if they were classified as having fecal incontinence before 6 years of age. Most patients who were 15-30 years of age had normal sexual function except for two females with irregular menstruation. These results indicate that achievement of fecal continence and sexual function in patients with high type anomalies treated by abdominoperineal rectoplasty depends on careful dissection as close as possible to the rectal wall and bringing the terminal bowel down exactly within the sling of the puborectal muscle.  相似文献   
10.
In the present study, we examined the expression of various protooncogenes and the specific binding of nuclear factor to c-myc gene in peripheral blood mononuclear cells (PBMC) from progressive systemic sclerosis (PSS) patients. We demonstrated first amplified expression of c-myc and c-myb gene and the existence of a nuclear protein specifically bound to 5'-non-coding fragment of c-myc gene. We then found a positive correlation between the degree of expression and/or affinity for the c-myc gene fragment of the nuclear protein and clinical disease activity. The amount of the factor was significantly reduced along with or prior to the amelioration of clinical symptoms and laboratory abnormalities with treatment. The significance of c-myc and c-myb proto-oncogene expression and nuclear factor specifically bound to c-myc gene is discussed.  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