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   6306篇
  免费   292篇
  国内免费   70篇
耳鼻咽喉   33篇
儿科学   122篇
妇产科学   63篇
基础医学   705篇
口腔科学   149篇
临床医学   467篇
内科学   1578篇
皮肤病学   226篇
神经病学   345篇
特种医学   231篇
外科学   1110篇
综合类   25篇
预防医学   217篇
眼科学   36篇
药学   355篇
中国医学   14篇
肿瘤学   992篇
  2024年   22篇
  2023年   76篇
  2022年   148篇
  2021年   249篇
  2020年   121篇
  2019年   192篇
  2018年   205篇
  2017年   142篇
  2016年   186篇
  2015年   181篇
  2014年   201篇
  2013年   233篇
  2012年   355篇
  2011年   393篇
  2010年   252篇
  2009年   158篇
  2008年   284篇
  2007年   326篇
  2006年   278篇
  2005年   281篇
  2004年   270篇
  2003年   248篇
  2002年   234篇
  2001年   153篇
  2000年   143篇
  1999年   161篇
  1998年   67篇
  1997年   64篇
  1996年   48篇
  1995年   42篇
  1994年   40篇
  1993年   29篇
  1992年   83篇
  1991年   66篇
  1990年   73篇
  1989年   68篇
  1988年   64篇
  1987年   59篇
  1986年   59篇
  1985年   59篇
  1984年   52篇
  1983年   34篇
  1982年   18篇
  1979年   26篇
  1973年   16篇
  1971年   26篇
  1970年   24篇
  1969年   16篇
  1967年   19篇
  1966年   20篇
排序方式: 共有6668条查询结果,搜索用时 31 毫秒
61.

Objective

The feasibility of multimodality therapy in patients with node-positive non-small cell lung cancer (NSCLC) requiring pneumonectomy and the role of pneumonectomy in N2 disease remain controversial. This study evaluated outcomes in patients with node-positive NSCLC undergoing pneumonectomy in a community hospital.

Methods

Perioperative and long-term outcomes of 37 patients with node-positive (pN1–2) NSCLC undergoing pneumonectomy from September 1994 to April 2010 as a clinical practice were retrospectively analyzed.

Results

Twenty patients received induction therapy, and 17 received preoperative chemoradiation (30–40 Gy). Fifteen patients and 22 patients underwent right and left pneumonectomy, respectively. A postoperative complication occurred in 8 patients. In-hospital mortality occurred in 1 patient. Induction therapy did not increase the operative risk including operative time, blood loss and postoperative complications. Nineteen patients were given a diagnosis of pN2. Although 7 bulky N2 patients and 10 multi-station N2 patients were included, 5-year overall survival was 34.3 % in pN1 and 28.0 % in pN2 (p = 0.998), respectively. Twenty-three patients received additional postoperative therapy. Five patients died within 3 months postoperatively due to distant metastases. Induction therapy and laterality did not influence survival. Extended resection, such as vagus nerve or chest wall resection, predicted an unfavorable outcome in multivariate analysis (Hazard ratio 2.81, p = 0.032).

Conclusions

The safety and acceptable long-term outcome of pneumonectomy as a general clinical practice were shown for both pN1 and pN2 patients with various preoperative or postoperative therapies. Extended resection due to the extrapleural or extranodal involvement of tumor was an unfavorable prognostic factor.  相似文献   
62.
Skip mediastinal nodal metastases in non-small cell lung cancer   总被引:1,自引:0,他引:1  
Objective: To reveal the incidence and clinical significance of mediastinal nodal metastases without N1-station nodal metastases (‘skip-N2 metastases’) in non-small cell lung cancer (NSCLC). Methods: A total of 450 NSCLC patients who underwent tumor resection with a systemic mediastinal nodal dissection were retrospectively reviewed. p53 status and proliferative activity represented as proliferative index (PI) were also examined immunohistochemically. Results: Skip-N2 metastases were documented in 49 (13%) patients of all 450 patients; among 334 patients without N1-nodal involvement, 18% patients had skip-N2 metastases. The postoperative survival of skip-N2 patients was almost same as that for patients with metastases to both N1 and N2 nodes. Skip-N2 metastases were significantly more frequent in male patients and squamous cell carcinoma patients. In addition, the mean PI for tumor with skip-N2 metastases was significantly higher than that for any other pathologic nodal (pN)-status diseases. Combined with histologic type and PI, the incidences of skip-N2 metastases for adenocarcinoma showing lower PI were only 5% (7/137) of all patients and 7% (7/94) of patients without N1-nodal involvement. Conclusions: N1 nodal status is not a useful predictor of N2 nodal status in NSCLC, because skip-N2 metastases were documented in 18% patients showing no N1-nodal involvement. However, N1 node-guided dissection might be performed in patients with adenocarcinoma showing lower PI, because the incidence of skip-N2 metastases was extremely low.  相似文献   
63.
Abstract Background: Advances in percutaneous coronary intervention (PCI) using drug‐eluting stents (DES) have impacted clinical practice. However, the efficacy of DES for dialysis patients still remains controversial. This study compares the early and long‐term clinical outcomes of coronary artery bypass grafting (CABG) and PCI with DES in dialysis patients. Methods: A retrospective review was performed in 125 dialysis patients treated between 2004 and 2007. Fifty‐eight patients underwent CABG and 67 underwent PCI with DES. The overall death, cardiac death, and cardiac‐related event rates were analyzed using the Kaplan‐Meier method. For the risk‐adjusted comparisons, multivariable logistic and Cox regression analyses were used. Results: The preoperative characteristics of the patients were similar except for the ejection fraction (p = 0.002) and the number of diseased vessels (p < 0.001). The 30‐day mortality was 0 in both groups. The overall survival rates at one, three, and five years were 84.2%, 64.7%, and 56.2% in CABG group and 88.2%, 75.5%, and 61.7% in DES group, respectively (p = 0.202). The rates of freedom from cardiac‐related events at one, three, and five years were 76.6%, 68.1%, and 48.6%, and 63.0%, 31.4%, and 0% in CABG and DES groups (p < 0.001), respectively, including seven (10%) late thromboses in the DES group. Although the risk‐adjusted analysis showed no significant difference for overall and cardiac death rates, the rates of cardiac‐related events and graft/stent failure were significantly higher in the DES group. Conclusions: CABG is superior for revascularization in dialysis patients compared with PCI using DES in terms of freedom from cardiac‐related events. (J Card Surg 2012;27:281‐287)  相似文献   
64.
Anterior mediastinal hemangiomas are very rare neoplasms in mediastinal tumors. A 58-year-old woman was revealed to have a mass measuring 4×3 cm in size in the anterior mediastinum with calcification on computed tomography. It was initially suspected to be a thymoma. We performed tumor extirpation in November 1998. The tumor was close to the thymus and slightly adhered to the superior vena cava, ascending aorta and right phrenic nerve, however, it did not invade any surrounding organs. Histopathologically, it was diagnosed to be a venous type hemangioma composed of vessels covered by smooth muscle and a cavernous type hemangioma composed of dilated vessels covered by one layer of endothelial cells.  相似文献   
65.
To evaluate laparoscopy-assisted Billroth-I gastrectomy (LADG), we examined the outcome of its use over the last 10 years. From December 1991 to December 2001, 116 patients with early gastric cancer underwent LADG in the surgical department of Oita Medical University and Koga hospital by the same surgical staffs. An operation record and clinical sheets were reviewed to obtain the operative findings, clinical course, and pathologic findings of resected specimens to evaluate the usefulness of LADG in the management of early gastric cancer. In all LADG procedures, regional lymph nodes dissection (D1+alpha) was successfully performed using laparoscopy. The mean operative duration and blood loss were 234 minutes and 139 mL, respectively. There were only four major complications, including pneumonia, leakage of anastomosis, pancreatic injury, and anastomotic stenosis, but all these cases were successfully treated conservatively. The mean length of postoperative stay was 16.3 +/- 2.5 days. All patients except one, who died not of cancer but of cerebral bleeding, were alive without recurrence or port-site metastasis during mean follow-up period of 45 months. We successfully performed 116 LADG procedures over 10 years. This procedure is recommended for the treatment of patients with early gastric cancer because of the associated good prognosis and several benefits, including less invasiveness and early recovery.  相似文献   
66.
Intraductal papillary mucinous neoplasm (IPMN) of the pancreas showed significantly less aggressive pathologic features compared with common pancreatic cancer. Therefore, several organ-preserving techniques, including duodenum-preserving pancreatic head resection, have been advocated in surgical procedures for IPMN. We describe a surgical technique of superior head resection of the pancreas with inferior branch preservation followed by a gastric wall-covering method for the prevention of pancreatic leakage in patients with IPMN of the pancreas head.  相似文献   
67.
Background/Purpose  While lipiodolized transarterial chemoembolization (lip-TACE) is effective for treating unresectable hepatocellular carcinoma (HCC), its effect for treating recurrent HCC after curative liver resection needs to be clarified. Methods  Of 163 patients who had undergone curative liver resection between 1992 and December 2003, 65 patients (39.8%) had recurrent HCC in the liver without extrahepatic recurrence and were indicated for lip-TACE. The overall survival rate after lip-TACE was calculated, and its correlation with factors such as the histology of the primary HCC and background noncancerous tissue were analyzed. Results  The overall survival rates after lip-TACE after the detection of the first recurrent HCC were 82.6%, 44.5%, and 24.8% at 1, 3, and 5 years, respectively. The factors affecting patient survival after lip-TACE were microscopic portal venous involvement of HCC at liver resection, grade of inflammation in the noncancerous liver parenchyma, and recurrence within 1 year after the initial liver resection. Multivariate analysis showed that the period between the resection and first recurrence had the highest hazard ratio. Conclusions  Lip-TACE is a reasonable procedure for treating recurrent HCC in selected patients who are not eligible for hepatic re-resection. When HCC recurred within 1 year from the primary liver resection, the effect of lip-TACE on patient survival was limited.  相似文献   
68.

Background

Saline-linked electric cautery (SLC) is introduced as an effective device to reduce blood loss in liver surgery. The aim of the current study was to evaluate the safety and efficacy of a 2-surgeon technique using SLC and the Cavitron Ultrasonic Surgical Aspirator (CUSA; Valleylab, Boulder, CO) in living donor hepatectomy.

Methods

Forty-three living donor right hepatectomy cases were enrolled in this study. The first 28 cases underwent liver transection with CUSA alone (CUSA group), while additional SLC was applied in the current 15 cases (2-surgeon technique, TS group).

Results

Blood loss was significantly reduced by the 2-surgeon technique (1,115.2 ± 652.9 g in CUSA group vs 732.3 ± 363.6 g in TS group, P < .05). In the TS group, there was no bile leakage from the cut surface. The early graft function and postoperative recipient survival were not significantly different between the groups.

Conclusions

According to our single-center experience, blood loss and donor complications in living donor hepatectomies were significantly reduced using a 2-surgeon technique using CUSA and SLC, while maintaining the graft viability.  相似文献   
69.
An 82-year-old woman presented with a 5-day history of right upper quadrant pain. A physical examination showed a palpable tender mass in the right upper quadrant with Murphy's sign. The contrast-enhanced multidetector computed tomography (MDCT) scan clearly showed the twisted pedicle of the cystic duct and gallbladder mesentery on the right side of the gallbladder, thus showing a “whirl sign,” and a definitive diagnosis of gallbladder torsion was made. The patient underwent a cholecystectomy, resulting in a favorable outcome. Therefore, the whirl sign on MDCT imaging can be a key to making a definitive diagnosis of gallbladder torsion.  相似文献   
70.
Hepatolithiasis is more frequently seen in East Asian countries than in Western countries, and it is well known to represent a high-risk state for intrahepatic cholangiocarcinoma. Intrahepatic cholangiocarcinoma is an aggressive tumor that shows a dismal outcome even after resection. Cancer results from multistep carcinogenesis; however, the precise molecular mechanisms involved in the genetic alterations in cancer remain unknown. The accumulation of alterations in cancer-related genes leads to disruptions in cell-cycle regulation and also to continuous cell proliferation. The present review provides an overview of cancer-related genes in intrahepatic cholangiocarcinogenesis arising in hepatolithiasis. Further study of molecular mechanisms in hepatolithiasis-related intrahepatic cholangiocarcinoma, and the delineation of the influence of the genes involved should lead to our understanding of cholangiocarcinogenesis.  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