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   1149篇
  免费   91篇
  国内免费   5篇
耳鼻咽喉   23篇
儿科学   33篇
妇产科学   16篇
基础医学   63篇
口腔科学   32篇
临床医学   95篇
内科学   338篇
皮肤病学   3篇
神经病学   68篇
特种医学   32篇
外科学   291篇
综合类   21篇
预防医学   58篇
眼科学   50篇
药学   79篇
中国医学   1篇
肿瘤学   42篇
  2023年   13篇
  2022年   19篇
  2021年   21篇
  2020年   17篇
  2019年   24篇
  2018年   23篇
  2017年   26篇
  2016年   28篇
  2015年   32篇
  2014年   40篇
  2013年   52篇
  2012年   71篇
  2011年   70篇
  2010年   40篇
  2009年   33篇
  2008年   66篇
  2007年   58篇
  2006年   65篇
  2005年   57篇
  2004年   43篇
  2003年   51篇
  2002年   48篇
  2001年   26篇
  2000年   30篇
  1999年   29篇
  1997年   6篇
  1996年   5篇
  1994年   8篇
  1993年   6篇
  1992年   18篇
  1991年   18篇
  1990年   15篇
  1989年   12篇
  1988年   14篇
  1987年   16篇
  1986年   6篇
  1985年   16篇
  1984年   13篇
  1983年   8篇
  1982年   4篇
  1979年   8篇
  1978年   4篇
  1977年   4篇
  1975年   5篇
  1974年   8篇
  1973年   4篇
  1972年   11篇
  1971年   13篇
  1970年   10篇
  1968年   4篇
排序方式: 共有1245条查询结果,搜索用时 15 毫秒
21.
Purpose: To compare the clinical outcomes in patients with chronic renal insufficiency (CRI) and renal artery stenosis (RAS) following renal artery (RA) stent placement with and without embolic protection device (EPD) usage. Materials and Methods: Eighteen patients who had RA stent placement with EPD were matched to control patients (RA stent only). Blood pressure, number of hypertensive medications, and estimated glomerular filtration rate (eGFR) at 3 months before the procedure and after 12 months were determined. An increase of ≥ 20% in eGFR at 12 months from baseline was defined as "improvement," decrease of ≥20% as "deterioration," and an eGFR change between those values as "stabilization" at 12 months. Results: At 12 months, stage 4 patients treated with EPD had significantly higher eGFR than controls (P = .01). There was no statistical difference in blood pressure outcomes between the 2 groups. Conclusions: Patients with stage 4 CRI did significantly better with EPD than those treated without it.  相似文献   
22.
Infection with the fungus Cryptococcus neoformans is seen predominantly in two forms: (a) pulmonary and (b) cerebromeningeal. Skeletal cryptococcosis is uncommon. There have been only occasional case reports of thoracic vertebral cryptococcosis presenting as cord compression. A young female had cervical lymphadenopathy diagnosed as tuberculosis by fine needle aspiration cytology (FNAC) and was on antitubercular therapy (ATT) for 5 months. She developed rapidly progressive paraparesis and imaging demonstrated a destructive vertebral body lesion involving T2-3 with a paraspinal abscess producing cord compression. A costotransversectomy with excision of the diseased bone and bone grafting was done. Histopathological examination revealed cryptococcosis. The patient was put on antifungal medication, but expired 2 weeks after surgery. Radiological, magnetic resonance imaging and surgical finding of vertebral cryptococcosis can mimic tuberculosis. The definite diagnosis of cryptococcosis depends upon microscopic identification of the organism. A high index of suspicion leading to early surgical confirmation and institution of anti fungal therapy is necessary to reduce the mortality and morbidity.  相似文献   
23.
24.
Colorectal cancer in patients younger than 40 years of age   总被引:5,自引:0,他引:5  
Previous studies have suggested a poor outcome for patients presenting with colorectal cancer under the age of 40 years. This study was conducted to evaluate the outcomes of these patients during a 10-year period at the Medical Center of Louisiana in New Orleans. A retrospective study was designed to review all patients under the age of 40 with a diagnosis of colorectal cancer from January 1990 to December 2000. There were 664 patients presenting with colorectal cancer during the 10-year period; of these 24 presented for surgery under the age of 40. There were 17 male and seven female patients. The median age was 35 years (range 22-39). Eleven (44%) patients had a positive family history of colorectal cancer. Seven lesions were right sided, one transverse, eight left sided, and eight rectal. Histologically 20 lesions were typical adenocarcinomas and four were mucinous. Twelve were stage IV, six stage III, five stage II, and one stage I. Twenty-one patients underwent resection, six with stoma formation; three patients had stoma formation only for a total of nine stomas (38%). The mean operative duration was 3.3 +/- 1.9 hours. The operative mortality was 4 per cent with a complication rate of 17 per cent. The eight rectal cancer patients received preoperative chemoradiation therapy (33%). Twelve (50%) patients with colon cancer received postoperative 5-fluorouracil-based chemotherapy. The mean survival for all patients was 24.7 +/- 23.2 months. Estimated 5-year survival using Kaplan-Meier analysis was 30 per cent. We conclude that colorectal cancer patients less than 40 years of age present at an advanced stage and tend to have a positive family history. In general patients tolerate surgery well, with stoma formation in more than one-third. Long-term survival is as predicted for their advanced stage of presentation. The study highlights the need for early diagnosis in this patient group.  相似文献   
25.

Background

Pharyngoesophageal stricture (PES) is an Achilles’ heel in the management of corrosive injury. Advances in endoscopic techniques were utilized in its management. We classified the stricture as per its dilatability and then planned their treatment.

Methods

PES was sub-categorized based on endoscopic dilatation and availability of cervical oesophagus: group-1 stricture with available cervical oesophagus; group-2 stricture with some part of upper oesophagus made available after endoscopic dilatation and anastomosis in cervico-pharyngeal area; group-3 stricture not amenable for dilatation, anastomosis done at the pharynx. Endoscopic dilatation was performed using through-the-scope pyloric balloon. Number and duration of dilatation sessions before surgery, incidence of tracheostomy, time and incidence for re-stricture and present status of swallowing were evaluated.

Results

Of 226 patients managed, 46 underwent oesophageal replacement for PES. Group 1, 2 and 3 had 12, 14 and 20 patients, respectively. An average 3 (2–4) preoperative balloon dilatation sessions were performed over 6–8 weeks. Tracheostomy was required in 1, 0, 8 patients (p = 0.010), and median hospital stay was 10, 9 and 13 days (p = 0.09) in group 1, 2, 3, respectively. Re-stricture developed in 4/12, 4/14, 9/20 patients with average sessions of dilatation required in post-operative period was 4, 3.5 and 8 in group 1, 2, 3, respectively. >90% of patients are taking normal diet in each group.

Conclusion

We attempted to avoid the high anastomosis by dilating the PES and step down the level of anastomosis in two-third patients. We thereby avoided tracheostomy, aspiration and swallowing problems related to high strictures.
  相似文献   
26.
Follow-up and surveillance form an important aspect of care in patients with colorectal cancers (CRC). Most recurrences will occur within 2 years of surgery and 90% by 5 years. Follow up protocols have not been well defined in stage I disease and the approach should be individualized. As 40% of patients with stages II and III will develop recurrences, intensive postoperative follow-up strategy is recommended for them. It includes visit to the clinician for clinical examination, serum carcinoembryonic antigen (CEA), computed tomography (CT) of the chest and abdomen, colonoscopy, and flexible proctosigmoidoscopy in rectal cancers. Surveillance should be undertaken in those who are medically fit for repeat surgical procedures or for chemoradiotherapy. The concept of intensive post operative surveillance is based on the fact that some of these patients can have resectable/curable recurrence.  相似文献   
27.
Development of a contralateral epidural haematoma during or immediately after cranial surgery is a well-described entity. However, in a case of acute subdural haematoma where the brain is usually tense, postoperative development of contralateral extradural haematoma is uncommon. We report two cases of contralateral extradural haematoma after decompressive surgery for acute subdural haematoma. We recommend routine postoperative CT immediately after cranial surgery for head trauma. This would help in timely detection and treatment of such a complication.  相似文献   
28.
29.
BACKGROUND: Although deep venous thrombosis (DVT) often complicates the clinical course in patients with cancer, few studies of the outcomes of DVT in this population have been published. Furthermore, the cost of DVT is largely undescribed. We herein report the largest study of DVT in this population to date. METHODS: We reviewed the medical records of 529 consecutive cancer patients in whom DVT developed from January 1, 1994, through December 31, 1997, and followed up these patients through December 31, 2000, for outcomes. The cost of hospitalization was obtained from our hospital's cost-accounting system and inflated to 2002 US dollars using the Consumer Price Index for Medical Care. Logistic regression was used to identify factors that were associated with a high risk of poor outcomes. RESULTS: The most common complication of DVT was bleeding, which occurred in 13% of patients. Pulmonary embolus occurred in 4%. Five patients (1%) died of complications of DVT and 5 (1%) of complications of anticoagulation. Recurrence of DVT was common (17% overall), particularly among those who had inferior vena cava filters (32%; P<.001) or a previous episode of DVT (P =.03). All but 4 patients were hospitalized for initial anticoagulation therapy, for a mean of 11 days. The mean cost of hospitalization was 2002 US $20 065. CONCLUSIONS: Among patients with cancer, DVT frequently is associated with serious clinical outcomes. Its treatment is resource intensive and costly. More effective agents and less costly management strategies could have a significant impact on the outcomes and cost of DVT in this population.  相似文献   
30.
Fetus in fetu is an extremely rare congenital anomaly. We describe the perinatal diagnosis and management of a fetus with oropharyngeal and cervical fetus in fetu. High‐resolution ultrasonography with 3‐dimensional rendering can identify increased risks of airway obstruction in utero. Early identification allows a multidisciplinary team to be assembled for a scheduled ex utero intrapartum treatment procedure.  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