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   394篇
  免费   18篇
耳鼻咽喉   3篇
儿科学   5篇
妇产科学   18篇
基础医学   70篇
口腔科学   8篇
临床医学   19篇
内科学   65篇
皮肤病学   2篇
神经病学   4篇
特种医学   53篇
外科学   64篇
综合类   47篇
预防医学   18篇
药学   22篇
肿瘤学   14篇
  2023年   3篇
  2022年   4篇
  2021年   9篇
  2020年   2篇
  2019年   10篇
  2018年   13篇
  2017年   4篇
  2016年   10篇
  2015年   8篇
  2014年   11篇
  2013年   14篇
  2012年   12篇
  2011年   15篇
  2010年   8篇
  2009年   19篇
  2008年   14篇
  2007年   22篇
  2006年   18篇
  2005年   22篇
  2004年   11篇
  2003年   14篇
  2002年   22篇
  2001年   10篇
  2000年   8篇
  1999年   13篇
  1998年   6篇
  1997年   7篇
  1996年   8篇
  1995年   9篇
  1994年   11篇
  1993年   6篇
  1992年   4篇
  1991年   5篇
  1990年   3篇
  1989年   4篇
  1988年   4篇
  1987年   3篇
  1986年   6篇
  1985年   3篇
  1984年   4篇
  1983年   7篇
  1982年   8篇
  1981年   4篇
  1980年   4篇
  1979年   2篇
  1977年   2篇
  1968年   1篇
  1966年   1篇
  1960年   1篇
  1927年   1篇
排序方式: 共有412条查询结果,搜索用时 0 毫秒
31.
Serial plain radiographic, ultrasound and CT findings of an unusual case of pulmonary blastoma are described with a review of the literature.  相似文献   
32.
33.
BACKGROUND: This study evaluated the usefulness of the serologic test for syphilis (STS) in preventing the transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses, and human T- lymphotropic virus via the transfusion of seronegative, infectious window-period blood. STUDY DESIGN AND METHODS: Demographic and laboratory information on blood donations made between January 1992 and June 1994 in 18 American Red Cross regions was analyzed. It was assumed that the same proportion of HIV-positive and HIV-infectious window- period donations reacted on STS and were negative on other screening tests (hepatitis B and C viruses and human T-lymphotropic virus). This proportion multiplied by the estimated number of HIV-infectious window- period donations is the number of post-screening HIV-infectious donations removed by STS. RESULTS: Of 4,468,570 donations, 12,145 (0.27%) were STS positive and 377 (0.008%) were HIV positive. Among donations that were negative on other screening tests, STS-reactive donations were 12 times more likely to be HIV positive (odds ratio = 11.9; 95% CI = 5,26). However, of an estimated 13 infectious window- period donations, 0.2 would have been removed because of a reactive STS, at a cost of over $16 million. CONCLUSION: STS is a poor marker and a costly strategy for preventing post-screening HIV infections and other blood-borne diseases.  相似文献   
34.
35.
Objective  Recently, a novel renal carcinoma with specific clinical and histological characteristics and translocation t(6;11)(p21.1;q12 or q13) has been identified. We have found 11 cases in the literature, and we are adding another 3 cases. Materials and methods  Three cases were found in the Plzeň pathological register with approximately 15,000 cases of kidney tumors. There were two females and 1 male, aged 22, 24, and 39 years. Results  The sizes of the tumors were 40, 136, and 10 mm. Two tumors were found incidentally; the biggest one was self-palpated by a 24-year-old pregnant patient. Patients are without any signs of disease 42, 20, and 17 months after surgery. Conclusion  This tumor is a distinctive and rare translocation carcinoma of the kidney [t(6;11), HMB45 positive]. All cases with known clinical data arose in younger people. The malignant potential is probably low. The work was supported by Czech government research project MSM 0021620819.  相似文献   
36.
37.
Background: Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative.  相似文献   
38.

Background

Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative.

Methods

Sixty consecutive cases requiring adenoidectomy were randomized into two groups of thirty each. Group A underwent conventional adenoidectomy using the curettage method and Group B underwent endoscopic assisted micro-debrider adenoidectomy. The parameters studied were intra-operative time, intra-operative bleeding and completeness of resection, collateral damage, post operative pain and recovery time.

Result

Sixty cases of adenoidectomy were done using conventional surgery and powered endoscopic adenoidectomy in the study period from Aug 04 to Dec 05. The time taken in Group A (conventional surgery) varied from 22–39 minutes (95% Confidence Interval (CI) −27.7 – 30.9)and in Group B (powered endoscopic surgery) from 27–55 minutes(95% CI 36.6 – 41.9) (p<0.05). The average blood loss in Group A was 21 ml (range 10–50) as compared to 31.67 ml (range 10-60) in Group B (p<0.05). The resection was invariably complete in Group B whereas seven(23%) cases had more than 50% residual adenoid tissue in Group A. Three cases in group A had collateral damage whereas in Group B, there were no added injuries. Post operative pain was studied only in cases undergoing adenoidectomy alone. Group A (n=8) demonstrated a pain score of 1.64–2.63–3.63 (95% CI) whereas Group B (n=11) demonstrated a pain score of 1.19–2.13–3.06 (95% CI). This difference was not statistically significant. In group A, the mean recovery period was 3.5 days and 2.93 days in Group B(p<0.05).

Conclusion

Endoscopic powered adenoidectomy was found to be a safe and effective tool for adenoidectomy. The study parameters where endoscopic powered adenoidectomy fared better were completeness of resection, accurate resection under vision, lesser collateral damage and faster recovery time. On the other hand, conventional adenoidectomy scored in matter of lesser operative time and intra-operative bleeding.Key Words: Adenoidectomy, Powered adenoidectomy, Endoscopic adenoidectomy  相似文献   
39.
Endotoxin-removal direct hemoperfusion column containing polymyxin B immobilized fibers (PMX-DHP) is an effective procedure for the treatment of sepsis-induced acute respiratory distress syndrome (ARDS). We investigated retrospectively the effects and appropriate timing of PMX-DHP induction for directly induced ARDS in 38 patients. PMX-DHP was carried out twice for two hours. Blood pressure, heart rate (HR) and PaO(2)/FIO(2) (PF) ratio, leukocytes, platelets, endotoxin, inflammatory cytokines and clusters of differentiated peripheral neutrophils and monocytes were measured before and after PMX-DHP. Acute Physiology and Chronic Health Evaluation (APACHE) II scores, Sequential Organ Failure Assessment (SOFA) scores and lung injury scores (LIS) were determined at the time of starting PMX-DHP. The underlying causes of ARDS were pneumonia in 29 patients and aspiration pneumonia in 9 patients. The patients were divided into Survivors (n = 21) and Nonsurvivors (n = 17). Mortality was 45% at 30 days after PMX-DHP. The APACHE II and SOFA scores and the LIS were not significantly different between the two groups. The time from the onset of ARDS to the start of PMX-DHP was significantly delayed between the two groups. PMX-DHP significantly improved the PF ratio, HR and systolic blood pressure in the Survivors compared to the Nonsurvivors. The function of active monocytes in the peripheral blood was significantly suppressed after PMX-DHP. This early induction of PMX-DHP is indicated for directly induced ARDS. In the Nonsurvivors, this delay could have led to undesirable responses to oxygenation and circulation after PMX-DHP.  相似文献   
40.

Purpose

An increased incidence of renal tumors has been observed in patients with end-stage-renal-disease (ESRD). The very strong association with acquired renal cystic disease (ACRD) and increased incidence of the renal tumors (conventional renal cell carcinoma (CRCC), papillary renal cell carcinoma (PRCC) or papillary renal cell adenoma (PRCA)) was reported. This study discusses the role of computed tomography (CT) in detecting renal tumors in patients with renal impairment: pre-dialysis, those receiving dialysis or with renal allograft transplants.

Materials and methods

Ten patients (nine male, one female) with renal cell tumors were enrolled into a retrospective study; two were new dialysis patients, three on long-term dialysis, and five were renal transplant recipients with history of dialysis. All patients underwent helical CT, a total of 11 procedures were performed. Sixteen-row detector system was used five times, and a 64-row detector system for the six examinations. All patients underwent nephrectomy of kidney with suspected tumor, 15 nephrectomies were performed, and 1 kidney was assessed during autopsy. CT findings were compared with macroscopic and microscopic assessments of the kidney specimen in 16 cases.

Results

Very advanced renal parenchyma atrophy with small cysts corresponding to ESRD was found in nine patients, chronic pyelonephritis in remained one. A spontaneously ruptured tumor was detected incidentally in one case, patient died 2 years later. In the present study, 6.25% (1/16) were multiple PRCA, 12.5% (2/16) were solitary PRCC, 12.5% tumors (2/16) were solitary conventional renal cell carcinomas (CRCC's), 12.5% tumors (2/16) were multiple conventional renal cell carcinomas (CRCC's), 25% (4/16) were CRCC's combined with multiple papillary renal cell carcinomas with adenomas (PRCC's and PRCA's), and 25% (4/16) of the tumors were multiple PRCC's combined with PRCA's without coexisting CRCC's. Bilateral renal tumors were found in our study in 60% (6/10) confirmed in six cases, one kidney left on follow-up due to the small tumors.

Conclusions

With the use of a multi-detector row system, it is possible to detect smaller foci suspected to originate in multiple tumors, especially when up to 3-mm thin multi-planar reconstructions are used. Two cases demonstrated the possibility the development of RCC in impaired kidneys may start before dialysis initiation.  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