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   5468篇
  免费   220篇
  国内免费   32篇
耳鼻咽喉   10篇
儿科学   105篇
妇产科学   24篇
基础医学   767篇
口腔科学   71篇
临床医学   377篇
内科学   1459篇
皮肤病学   64篇
神经病学   481篇
特种医学   311篇
外科学   966篇
综合类   21篇
预防医学   108篇
眼科学   93篇
药学   275篇
中国医学   19篇
肿瘤学   569篇
  2023年   21篇
  2022年   58篇
  2021年   97篇
  2020年   63篇
  2019年   86篇
  2018年   117篇
  2017年   110篇
  2016年   106篇
  2015年   146篇
  2014年   163篇
  2013年   221篇
  2012年   316篇
  2011年   335篇
  2010年   174篇
  2009年   156篇
  2008年   246篇
  2007年   282篇
  2006年   290篇
  2005年   315篇
  2004年   307篇
  2003年   295篇
  2002年   269篇
  2001年   88篇
  2000年   82篇
  1999年   72篇
  1998年   53篇
  1997年   60篇
  1996年   70篇
  1995年   59篇
  1994年   51篇
  1993年   33篇
  1992年   52篇
  1991年   67篇
  1990年   50篇
  1989年   102篇
  1988年   86篇
  1987年   107篇
  1986年   96篇
  1985年   76篇
  1984年   49篇
  1983年   33篇
  1982年   25篇
  1981年   31篇
  1980年   24篇
  1979年   35篇
  1978年   34篇
  1977年   24篇
  1973年   15篇
  1972年   9篇
  1969年   10篇
排序方式: 共有5720条查询结果,搜索用时 15 毫秒
81.
We carried out a nationwide survey on patients less than 20 years of age with pediatric chronic end-stage renal disease (ESRD) in Japan for the year 1998. There were 582 patients who had started on renal replacement therapy before 1998, and 105 patients who had been newly introduced to renal replacement therapy in that year. The prevalence rate of the ESRD patients already on treatment was 22 per million population (aged 0–19 years) in 1998. Older patients had a higher prevalence rate than younger ones. There were 345 patients on dialysis as of 1 January 1998, and 237 patients with transplants. The major diseases causing ESRD were renal hypoplasia/dysplasia and focal segmental glomerulosclerosis. Of the 237 patients (46.9%) who had received renal transplants before 1 January 1998, 262 patients (96%) received their transplants from living kidney donors. The incidence rate for the new ESRD patients was 4 per million population (aged 0–19 years) in 1998. Older patients had a slightly higher incidence rate than younger ones. Peritoneal dialysis was used more frequently than hemodialysis under 15 years (85%–95% and 39% respec-tively), especially in very young patients. The major diseases causing ESRD were the same as in the patients already on treatment. The transplant rate for the year 1998 was 10 per 100 dialysis patient-years (patients aged 0–19 years) with 9 living kidney donors. The death rate was 15.6 per 1,000 dialysis patient-years (patients aged 0–19 years); the major causes of death being cardiovascular diseases and infections. Received: 30 January 2001 / Revised: 3 January 2002 / Accepted: 4 January 2002  相似文献   
82.
BACKGROUND AND OBJECTIVES: Different techniques of continuous renal replacement therapy (CRRT) might have different effects on azotemic control. Accordingly, we tested whether continuous veno-venous hemodiafiltration (CVVHDF) or continuous veno-venous hemofiltration (CVVH) would achieve better control of serum creatinine and plasma urea levels. DESIGN: Retrospective controlled study. SETTING: Two tertiary Intensive Care Units. PATIENTS: Critically ill patients with acute renal failure (ARF) treated with CVVHDF (n = 49) or CVVH (n = 50). Interventions: Retrieval of daily morning urea and creatinine values before and after the initiation of CRRT for up to 2 weeks of treatment. MEASUREMENTS AND RESULTS: Before treatment, serum urea and creatinine concentrations were significantly lower in the CVVH group than in CVVHDF group (urea: 31.0 +/- 15.0 mmol/L for CVVHDF and 24.7 +/- 16.1 mmol/L for CVVH, p = 0.01, creatinine: 547 +/- 308 micromol/L vs. 326 +/- 250 micromol/L, p < 0.0001). These differences were still significant after 48 h of treatment (urea: 20.1 +/- 8.3 mmol/L vs. 14.1 +/- 6.1 mmol/L; p = 0.0003, creatinine: 360 +/- 189pmol/L vs. 215 +/- 118 micromol/L; p < 0.0001). Throughout the duration of therapy, mean urea levels (22.3 +/- 9.0 mmol/L for CVVHDF vs. 16.7 +/- 7.8 mmol/L for CVVH, p < 0.0001) and mean creatinine levels (302 +/- 167 vs. 211 +/- 103 micromol/L, p < 0.0001) were better controlled in the CVVH group. CONCLUSIONS: CRRT strategies based on different techniques might have a significantly different impact on azotemic control.  相似文献   
83.

Background

Trans-right axillary aortic valve replacement (TAX-AVR) remains uncommon. We developed a special method to pull the heart closer to the right chest wall to make the surgery as easy and safe as aortic valve replacement via median sternotomy. Because the retraction sutures lifting the ascending aorta and aortic root are arranged circularly around the wound, we named this technique “Stonehenge technique”.

Methods

We examined 47 patients who underwent aortic valve replacement through a small right infra-axillary thoracotomy as the initial surgical therapy. These patients were divided into two groups: the conventional TAX-AVR group that underwent AVR via the conventional small right axillary incision approach (n?=?20) and the TAX-AVR with SH group that underwent AVR with the Stonehenge technique (n?=?27).

Results

The aortic cross-clamp and the extracorporeal circulation time were significantly shorter in the TAX-AVR with SH group than in the conventional TAX-AVR group (conventional TAX-AVR group: 125.5?±?47.9; TAX-AVR with SH group: 96.0?±?14.0, p?=?0.004, and conventional TAX-AVR group: 163.8?±?55.9; TAX-AVR with SH group: 140.0?±?16.8, p?=?0.04).

Conclusion

The outcomes of this technique depend on the site of the retraction sutures in the opened pericardium, direction of pull, amount of force applied, and precautions taken. If performed correctly, the ascending aorta and the root can be pulled from the wound to within the surgeon’s fingers’ reach, thereby reducing aortic cross-clamp and extracorporeal circulation times in group of minimally invasive aortic valve replacement via right infra-axillary thoracotomy.
  相似文献   
84.

Background  

Superficial esophageal neoplasias resected in piecemeal manner with endoscopic mucosal resection (EMR) sometimes recur locally, and additional treatments need to be developed. Efficacy and safety of endoscopic submucosal dissection (ESD) for esophageal neoplasias are not sufficiently demonstrated, so we conducted a retrospective study to evaluate the efficacy and safety of ESD for superficial esophageal neoplasias.  相似文献   
85.
The present study investigated intra‐articular injection of bone‐marrow‐derived mesenchymal stem cells (MSCs) combined with articulated joint distraction as treatment for osteochondral defects. Large osteochondral defects were created in the weight‐bearing area of the medial femoral condyle in rabbit knees. Four weeks after defect creation, rabbits were divided into six groups: control group, MSC group, distraction group, distraction + MSC group, temporary distraction group, and temporary distraction + MSC group. Groups with MSC received intra‐articular injection of MSCs. Groups with distraction underwent articulated distraction arthroplasty. Groups with temporary distraction discontinued the distraction after 4 weeks. The rabbits were euthanized at 4, 8, and 12 weeks after treatment except temporary distraction groups which were euthanized at only 12 weeks. Histological scores in the distraction + MSC group were significantly better than in the control, MSC group or distraction group at 4 and 8 weeks, but showed no further improvement. At 12 weeks, the temporary distraction + MSC group showed the best results, demonstrating hyaline cartilage repair with regeneration of the osteochondral junction. In conclusion, joint distraction with intra‐articular injection of MSCs promotes early cartilage repair, and compressive loading of the repair tissue after temporary distraction stimulates articular cartilage regeneration. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1466–1473, 2015.  相似文献   
86.
Medical radiation exposure increases the likelihood of cataract formation. A personal dosimeter was attached to the left temple of 77 anaesthetists during 45 endovascular aortic aneurysm repairs and 32 interventional neuroradiology procedures. Compared with interventional neuroradiology, the median (IQR [range]) total radiation dose emitted by fluoroscopic equipment was significantly lower during endovascular aortic aneurysm repair (4175 (3127–5091 [644–9761]) mGy than interventional neuroradiology (1420 (613–2424 [165–10 840]) mGy, p < 0.001). However, radiation exposure to the anaesthetist's temple was significantly greater during endovascular aortic aneurysm repair (15 (6–41 [1–109]) μSv) than interventional neuroradiology (4 (2–8 [0–67]) μSv, p < 0.001). These data suggest that anaesthetists at our institution would have to deliver anaesthesia for ~1300 endovascular aortic aneurysm repairs and ~5000 interventional neuroradiology cases annually to exceed the general occupational limits, and ~10 000 endovascular aortic aneurysm repairs and ~37 500 interventional neuroradiology cases to exceed the ocular exposure limits recommended by the International Commission on Radiological Protection. Nevertheless, anaesthetists should be aware of the risk of ocular radiation exposure, and reduce this by limiting the time of exposure, increasing the distance from the source of radiation, and shielding.  相似文献   
87.
We conducted a phase II study using docetaxel and trastuzumab as preoperative systemic treatment for locally advanced HER-2-overexpressing breast cancer (stage IIIB or IIIC) to evaluate the efficacy and safety, and to perform a subset analysis based on tumor biomarkers. Patients received 4 mg/kg trastuzumab on day 1, followed by weekly treatments of 2 mg/kg, in addition to 75 mg/m2 docetaxel every 3 weeks for 4 cycles before surgery. The primary end point was clinical response rate measured by MRI or CT. Twenty-five patients were enrolled. The median age was 54 years and median tumor size was 63 mm. The overall clinical response rate was 68% [95% CI: 47–85%] and the pCR rate was 22% [95% CI: 8–44%]. The clinical response and the pCR rates of patients with ER- and PgR- tumors were 79% and 31%, respectively, while they were 55% and 10%, respectively, in the patients with ER+ and/or PgR+ tumors (p = 0.34, p = 0.34, respectively). Cardiac toxicity was well tolerated; there was no evidence of clinical cardiac events in any patient. The combination of docetaxel and trastuzumab produced highly favorable clinical and pathological responses for locally advanced HER-2-overexpressing breast cancer. Subgroup analysis suggests that ER/PgR negative tumors might be associated with pathological response in locally advanced breast cancer.  相似文献   
88.

Background

Rectal carcinoid tumors 10 mm in diameter or smaller located within the submucosal layer can be cured by local excision including endoscopic treatment. But complete resection of these tumors with endoscopic polypectomy is difficult. This study aimed to evaluate the usefulness of endoscopic submucosal dissection (ESD) and endoscopic ultrasonography (EUS) for the treatment of rectal carcinoid tumors.

Methods

In this study, 22 rectal carcinoid tumors in 21 patients were evaluated with EUS and treated using ESD from January 2004 to December 2008.

Results

The mean size of the resected tumors was 6.1 mm (range, 2.0–10 mm) on histopathologic evaluations. When the sizes of the tumors shown by EUS and histopathologic evaluation were compared, the mean values were not significantly different. All the tumors were located within the submucosal layer, and the accuracy of the preoperative depth determination with EUS was 100% (22/22). The mean duration of the ESD procedure was 37 min (range, 20–71 min). The overall rate of en bloc resection with ESD was 100% (22/22). Although postoperative bleeding occurred in two cases (9%), both cases were successfully managed by endoscopic hemostasis. No perforation or recurrence was observed during the mean follow-up period of 30 months (range, 7–66 months).

Conclusions

Endoscopic submucosal dissection and preoperative assessment with EUS are effective for treating rectal carcinoid tumors and enabling en bloc resection.  相似文献   
89.
We report a case of rupture of the flexor tendons to the index finger after arthrodesis of the basal joint of the thumb. The tendons ruptured as a result of the Kirschner wires having penetrated in the carpal tunnel. This unusual complication was treated by tendon graft of the palmaris longus tendon.  相似文献   
90.
Purpose To determine the incidence and importance of functioning tumors among incidentally discovered adrenal masses in the era of laparoscopic surgery. Methods We defined adrenal incidentaloma as a tumor detected during abdominal imaging for adrenal-unrelated reasons, and we reviewed 197 consecutive patients with adrenal incidentaloma diagnosed since we started laparoscopic adrenalectomy. Results Incidentaloma was discovered initially in 91 (46%) patients and pheochromocytoma was detected as an incidentaloma in 21 (39%) of 54 patients. One patient, a 21-year-old woman taking mesalamine for ulcerative colitis, had a remarkably elevated urinary normetanephrine level, which resulted in the initial misdiagnosis of a 10-cm right adrenal incidentaloma as a pheochromocytoma. Laparoscopic right adrenalectomy resulted in a pathological diagnosis of ganglioneuroma. A series of urinary normetanephrine measurements were taken in parallel with the mesalamine doses. We found that other patients medicated with mesalamine, without adrenal tumors, had elevated urinary normetanephrine levels, confirming that mesalamine metabolites interfere with urinary normetanephrine measurements. Conclusions It is essential to diagnose the functional potential of adrenal incidentaloma preoperatively, and not to perform laparoscopic adrenalectomy for adrenal incidentaloma without careful evaluation first.  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