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   3252篇
  免费   144篇
  国内免费   41篇
耳鼻咽喉   31篇
儿科学   34篇
妇产科学   111篇
基础医学   292篇
口腔科学   106篇
临床医学   253篇
内科学   776篇
皮肤病学   39篇
神经病学   261篇
特种医学   121篇
外科学   728篇
综合类   18篇
预防医学   134篇
眼科学   152篇
药学   159篇
中国医学   2篇
肿瘤学   220篇
  2023年   32篇
  2022年   78篇
  2021年   113篇
  2020年   62篇
  2019年   88篇
  2018年   132篇
  2017年   99篇
  2016年   95篇
  2015年   119篇
  2014年   142篇
  2013年   185篇
  2012年   262篇
  2011年   280篇
  2010年   143篇
  2009年   149篇
  2008年   273篇
  2007年   273篇
  2006年   217篇
  2005年   193篇
  2004年   169篇
  2003年   114篇
  2002年   109篇
  2001年   13篇
  2000年   5篇
  1999年   9篇
  1998年   22篇
  1997年   8篇
  1996年   10篇
  1995年   7篇
  1994年   5篇
  1993年   1篇
  1991年   2篇
  1990年   1篇
  1988年   2篇
  1987年   2篇
  1983年   1篇
  1982年   4篇
  1981年   2篇
  1980年   1篇
  1978年   3篇
  1977年   2篇
  1976年   2篇
  1965年   1篇
  1964年   3篇
  1963年   2篇
  1960年   1篇
  1959年   1篇
排序方式: 共有3437条查询结果,搜索用时 15 毫秒
41.
Spigelian hernia (1-2% of all hernias) is the protrusion of preperitoneal fat, peritoneal sac, or organ(s) through a congenital or acquired defect in the spigelian aponeurosis (i.e., the aponeurosis of the transverse abdominal muscle limited by the linea semilunaris laterally and the lateral edge of the rectus muscle medially). Mostly, these hernias lie in the "spigelian hernia belt," a transverse 6-cm-wide zone above the interspinal plane; lower hernias are rare and should be differentiated from direct inguinal or supravescical hernias. Although named after Adriaan van der Spieghel, he only described the semilunar line (linea Spigeli) in 1645. Josef Klinkosch in 1764 first defined the spigelian hernia as a defect in the semilunar line. Defects in the aponeurosis of transverse abdominal muscle (mainly under the arcuate line and more often in obese individuals) have been considered as the principal etiologic factor. Pediatric cases, especially neonates and infants, are mostly congenital. Embryologically, spigelian hernias may represent the clinical outcome of weak areas in the continuation of aponeuroses of layered abdominal muscles as they develop separately in the mesenchyme of the somatopleura, originating from the invading and fusing myotomes. Traditionally, repair consists of open anterior herniorraphy, using direct muscle approximation, mesh, and prostheses. Laparoscopy, preferably a totally extraperitoneal procedure, or intraperitoneal when other surgical repairs are planned within the same procedure, is currently employed as an adjunct to diagnosis and treatment of spigelian hernias. Care must be taken not to create iatrogenic spigelian hernias when using laparoscopy trocars or classic drains in the spigelian aponeurosis.  相似文献   
42.
43.
100 multivisceral transplants at a single center   总被引:7,自引:0,他引:7       下载免费PDF全文
OBJECTIVE: The objective of this study was to summarize the evolution of multivisceral transplantation over a decade of experience and evaluate its current status. SUMMARY BACKGROUND DATA: Multivisceral transplantation can be valuable for the treatment of patients with massive abdominal catastrophes. Its major limitations have been technical and rejection of the intestinal graft. METHODS: This study consisted of an outcome analysis of 98 consecutive patients who received multivisceral transplantation at our institution. This represents the largest single center experience to date. RESULTS: The most common diseases in our population before transplant were intestinal gastroschisis and intestinal dysmotility syndromes in children, and mesenteric thrombosis and trauma in adults. Kaplan Meier estimated patient and graft survivals for all cases were 65% and 63% at 1 year, 49% and 47% at 3 years, and 49% and 47% at 5 years. Factors that adversely influenced patient survival included transplant before 1998 (P = 0.01), being hospitalized at the time of transplant (P = 0.05), and being a child who received Campath-1H induction (P = 0.03). Among 37 patients who had none of these 3 factors (15 adults and 22 children), estimated 1- and 3-year survivals were 89% and 71%, respectively. Patients transplanted since 2001 had significantly less moderate and severe rejections (31.6% vs 67.6%, P = 0.0005) with almost half of these patients never developing rejection. CONCLUSIONS: Multivisceral transplantation is now an effective treatment of patients with complex abdominal pathology. The incidences of serious acute rejection and patient survival have improved in the most recent experience. Our results show that the multivisceral graft seems to facilitate engraftment of transplanted organs and raises the possibility that there is a degree of immunologic protection afforded by this procedure.  相似文献   
44.

Background

Subintimal endovascular intervention has been used widely in the treatment of symptomatic superficial femoral artery (SFA) occlusion. The relative effectiveness of subintimal placement of a covered stent (CS) versus balloon-only subintimal angioplasty (SIA) remains uncertain.

Methods

We performed a retrospective cohort study of consecutive patients with symptomatic SFA occlusions (>15 cm) who underwent subintimal endovascular intervention, either CS or SIA, in a single institution. Primary patency was the primary outcome. Secondary outcomes included complication rates, freedom from re-intervention, and limb salvage rates. Patency was ascertained with followup duplex or clinically.

Results

We evaluated 57 patients in the SIA group and 31 patients in the CS group. At 1 year the SFA primary patency for the SIA and CS groups was 28% versus 75% (P < .001), whereas the primary assisted patency was 37% versus 84% (P < .001), respectively. Need for bypass was 13% versus 0% (P = .05) in the SIA and CS groups, respectively.

Conclusions

Placement of a covered stent improves patency after subintimal intervention for long SFA occlusion.  相似文献   
45.
46.

Background

Laparoscopic-endoscopic single-site surgery (LESS) represents the closest surgical technique to scar-free surgery.

Objective

To assess the feasibility of LESS radical nephrectomy (LESS-RN).

Design, setting, and participants

Ten patients with body mass index (BMI) ≤30 underwent LESS-RN for renal tumour by two experienced laparoscopists.

Surgical procedure

TriPort (Olympus Winter &; Ibe, Hamburg, Germany) was inserted through a transumbilical incision. A combination of standard laparoscopic instruments and flexible grasper and scissors was used. A 5-mm 30° camera was also used. The standard laparoscopic transperitoneal nephrectomy technique was performed.

Measurements

Patient demographics, operative details, and final pathology were prospectively recorded. Postoperative evaluation of pain and use of analgesic medication were recorded.

Results and limitations

Ten cases were successfully accomplished (two right-sided tumours and eight left-sided tumours; tumour diameter ranges: 4–8 cm). The mean patient age was 63.5 yr (22–77 yr), and median BMI was 23.56 (18.2–26.6). The mean operative time was 146.4 min (120–180 min), and the mean blood loss was 202 ml (50–900 ml). Pathological examination observed organ-confined T1 renal cell carcinoma in nine cases and pT3b tumour in one case. One bleeding complication occurred. Limitations regarding the intraoperative instrument ergonomics and the requirement for ambidexterity of the surgeon were noted.

Conclusions

LESS-RN proved to be safe and feasible. Further clinical investigation in comparison to the established techniques should take place to evaluate the outcome of LESS-RN.  相似文献   
47.

Background

The safety of laparoscopic major liver resections is still uncertain. The aim of this study was to compare our results for laparoscopic right hepatectomy (LRH) with those for open right hepatectomy (ORH).

Methods

Patients undergoing LRH were compared with retrospectively selected patients from our ORH database. The 2 groups were well matched for sex, age, American Society of Anesthesiologists score, body mass index, liver disease, and tumor size. Surgical and postsurgical outcomes were compared.

Results

Seventy-two patients were analyzed: 22 in the LRH group and 50 in the ORH group. Operating time was similar. Blood loss was significantly less in laparoscopic resections (P = .038). Specific morbidity rates were not different, general morbidity was lower after laparoscopy (P = .04), and the severity of postsurgical complications was not different. Mean hospital stay was significantly shorter after laparoscopy (P = .009).

Comments

Laparoscopy improved surgical and postsurgical outcomes for ORH in selected patients. This is the first comparative study to demonstrate an advantage of laparoscopy for a major liver resection. Prospective randomized studies with a greater number of cases are needed to confirm the role of laparoscopy in major liver resections.  相似文献   
48.
Methods:Data on 11 robot-assisted laparoscopic partial nephrectomies performed by using our technique from February 2015 through June 2015 were retrospectively analyzed. The robotic platform used was DaVinci Xi (Intuitive Surgical, Inc., Sunnyvale, California, USA) with a 3-arm setup. The AirSeal system (SurgiQuest, Milford, Connecticut, USA) was used as a port allowing simultaneous introduction of 2 instruments for the bedside surgeon, obviating the need for an additional (fourth) robotic arm. A long suction-and-irrigation device and atraumatic grasping forceps were used. Both instruments were introduced through the trocar of the AirSeal system, making simultaneous introduction and use possible. We preferred the long suction-and-irrigation device, because it minimizes collision of the instruments.Results:Mean age and BMI of the patients were 55 ±14.6 y and 29.18 ± 6.85, respectively. Seven tumors were on the right side and 4 were on the left. The mean size of the tumors was 32.45 mm (± 11.31). Surgical time was 132.2 minutes (±37.17), with an estimated blood loss and ischemia time of 103.63 mL (±65.92) and 16.72 minutes (±9.52), respectively. One patient had postoperative bleeding that was resolved without transfusion. The median hospitalization period was 3.9 d (±0.53). Loss of intra-abdominal pressure was not observed, and pressure was stable at 10 mm Hg.Conclusion:The AirSeal System and its valveless trocar eliminated the need for an additional port placement in our series. The technique is feasible, safe, and reproducible; therefore, it may be implemented in selected cases of robot-assisted partial nephrectomies.  相似文献   
49.
OBJECTIVES: Although the short-term results of supracondylar periprosthetic fractures treated with retrograde nailing have been satisfactory, there is always a concern about the long-term survival of the prosthesis. The aim of the study was to evaluate fracture healing and knee functional outcome with a follow-up time of at least 2 years in periprosthetic fractures of the knee treated with a supracondylar nail. DESIGN: Cohort study. PATIENTS: There were 9 patients with 10 periprosthetic fractures. In 1 patient, the fracture occurred intraoperatively. In the others, the time between the total knee arthroplasty and the periprosthetic fracture ranged between 2 weeks and 7 years (average time: 2.78 years). The mean follow-up was 34.5 months (25-52 months). MAIN OUTCOME MEASUREMENTS: The Western Ontario and McMaster Universities index was used to evaluate the functional result postoperatively using the paired t test as the statistical test. Fracture union was assessed with plain x-rays. RESULTS: All the fractures united within 3 months. One fracture united in extreme valgus (35 degrees) and was revised to a stemmed total knee replacement. There were no infections and no prosthesis loosening. The paired t test before the fracture and after the operation demonstrated no statistically significant differences; however, there was a trend toward lower functional score postoperatively. CONCLUSIONS: It appears that retrograde nailing is a reliable technique to treat periprosthetic supracondylar fractures. It provides adequate stability until fracture union. The morbidity of the operation is minimal, and the complication rate is low. The midterm results in our study showed that none of the prostheses required revision. In our opinion, it is the treatment of choice for a periprosthetic fracture when the prosthesis is stable.  相似文献   
50.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  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