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   1631篇
  免费   52篇
  国内免费   9篇
耳鼻咽喉   35篇
儿科学   103篇
妇产科学   66篇
基础医学   83篇
口腔科学   70篇
临床医学   134篇
内科学   313篇
皮肤病学   28篇
神经病学   84篇
特种医学   58篇
外科学   459篇
综合类   24篇
一般理论   1篇
预防医学   30篇
眼科学   48篇
药学   63篇
中国医学   6篇
肿瘤学   87篇
  2023年   15篇
  2022年   20篇
  2021年   29篇
  2020年   22篇
  2019年   34篇
  2018年   28篇
  2017年   28篇
  2016年   52篇
  2015年   53篇
  2014年   65篇
  2013年   117篇
  2012年   118篇
  2011年   104篇
  2010年   77篇
  2009年   72篇
  2008年   114篇
  2007年   131篇
  2006年   115篇
  2005年   114篇
  2004年   113篇
  2003年   89篇
  2002年   83篇
  2001年   17篇
  2000年   12篇
  1999年   13篇
  1998年   5篇
  1997年   7篇
  1996年   8篇
  1995年   9篇
  1994年   5篇
  1993年   7篇
  1992年   4篇
  1991年   1篇
  1990年   5篇
  1989年   1篇
  1987年   1篇
  1986年   2篇
  1967年   1篇
  1908年   1篇
排序方式: 共有1692条查询结果,搜索用时 0 毫秒
1.
Defects in the sacrococcygeal and ischial soft tissues can be treated with gluteus maximus and posterior thigh V-Y advancement flaps. However, late complications include recurrence and dehiscence of the suture line. Increasing the amount of the soft tissues over the bony prominences and multilayered closure may have an advantage for long-term durability. We modified the V-Y advancement technique by de-epithelialising the medial parts of the flap and burying them under the opposing edge of the wound or the flap. Sixteen patients with various defects of the sacrococcygeal and ischial soft tissues were operated on using this technique. All the flaps healed well with no partial or complete loss of the flap. Three patients developed complications. The main advantage of our technique is the use of healthy tissues to obliterate the dead spaces under the edges of the wound or the opposing flap. In this way, not only the defect in the skin but the defect in the subcutaneous tissue, with its iceberg tip at the surface, is treated effectively. To have an additional layer of tissue between the bone and the superficial tissues provides an extra cushion of soft tissue and avoids putting the suture line directly over the bony prominences. We used this modification safely for both unilateral and bilateral flaps. It could also be used successfully in other parts of the body.  相似文献   
2.
Purpose: To evaluate the effects of topical timolol and apraclonidine on retrobulbar blood flow velocity waveforms in a group of healthy volunteers.Methods: Apraclonidine 1% and timolol maleate 0.5% single dose administrations were crossed over double masked in 12 healthy volunteers. The intraocular pressure measurements were followed by Doppler examination of the ophthalmic artery and the central retinal artery.Results: Intraocular pressure was reduced significantly on both treated and fellow eyes after timolol (p = 0.003, p = 0.04 respectively) and after apraclonidine (p = 0.002, p = 0.01 respectively). After apraclonidine administration end diastolic velocity, mean velocity decreased and pulsatility index increased in the ophthalmic artery of both treated and fellow eyes. Resistivity index increased and peak systolic velocity decreased only in the ophthalmic artery of treated eyes. All Doppler indices remained nonsignificant for central retinal artery of both eyes.After timolol administration there were no significant changes of the Doppler indices in the ophthalmic artery and central retinal artery of the treated and fellow eyes.Conclusion: Topical timolol and apraclonidine significantly reduced the intraocular pressure. Single dose administration of apraclonidine 1% increased the vascular impedance distal to the ophthalmic artery. On the other hand, timolol 0.5% had no effect on vascular impedance.  相似文献   
3.
4.
OBJECTIVE: An endometrioid adenocarcinoma (EAC) with true trophoblastic differentiation is a rare event with a highly aggressive clinical course. CASE: We report an endometrioid adenocarcinoma of the endometrium in which there was a morphologically conventional-appearing EAC component admixed with multinucleated giant cells and large pleomorphic tumor cells that resembled a choriocarcinoma without an elevated serum level of human chorionic gonadotropin (hCG) in a 42-year-old unmarried woman with a history of abnormal uterine bleeding. A total abdominal hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymph node dissection were performed. Histopathologic study of the specimen showed endometrioid adenocarcinoma extended to the deep myometrium with a focus of hemorrhagic and necrotic tumor composed of multinucleated giant cells, large pleomorphic tumor cells, suggesting choriocarcinomatous differentiation (CD). Immunohistochemical studies demonstrated intense reactivity of tumor cells for human chorionic gonadotropin (hCG) confirming the diagnosis. A complete clinical workup ruled out metastatic spread to the brain, lungs, skeleton, or abdomen. The patient was alive with no evidence of disease 6 months later. CONCLUSION: Although endometrioid adenocarcinoma with choriocarcinomatous differentiation is known to behave in a more aggressive course, this disease may have a good prognosis with a clinically indolent course when it is small, and without elevated serum hCG levels.  相似文献   
5.
Objectives Although development of new treatment modalities limited digoxin usage, digoxin intoxication is still an important issue which could be easily overlooked. In this report we analyzed a case series definitively diagnosed as digoxin intoxication in the modern era. Methods We analyzed 71 patients hospitalized with digoxin intoxication confirmed by history, complaints, clinical and electrocardiograph (ECG) findings, and serum digoxin levels > 2.0 ng/mL, during a five year period. The demographic and clinical data, indications for digoxin use, digoxin dosage, concurrent medications, laboratory data, hospital monitoring, and ECG findings were obtained from all patients. Results Thirty-eight of 71 patients (53.5%) had symptoms of heart failure during admission or later. Sixty-four percent of patients were older than 75 years. The percentage of females was 67%. Atrial fibrillation, hypertension and gastrointestinal complaints were more frequent in the females (64% in females, 30% in males, P = 0.007; 81% in female, 52% in males, P = 0.01; 50% in female, 17.3% in males, P = 0.008, respectively). The mortality rate during the hospital course was 7%. Conclusion This report demonstrated the reduced mortality rates in patients with digoxin intoxication over the study period. Gastrointestinal complaints are the most common symptoms in this population.  相似文献   
6.
Accidental or intentional falls from a height are a form of blunt trauma and occur frequently in forensic medicine. Reports describing elevator accidents as a small subcategory of falls from heights are rare in the medical literature and no report on injury patterns or scene reconstruction of such an accident was found. A case of an accident in a hydraulic elevator with a man falling 3m was examined using post-mortem multi-slice computed tomography (MSCT) and autopsy. The man suffered an unusually extensive trauma and died at the scene. Post-mortem MSCT examination showed a comminute fracture of the skull, the right femur and the first lumbar vertebra. Severe lacerations of the brain with epidural, subdural and subarachnoidal haemorrhages over both hemispheres were diagnosed. Autopsy confirmed these findings. To reconstruct the accident we used radiological and autopsy results as well as findings at the scene.  相似文献   
7.
PURPOSE: Retroperitoneal lymph node dissection (RPLND) for testicular cancer is an important treatment modality for patients with stage I or IIA disease. Several urologists have previously reported the feasibility and usefulness of laparoscopic RPLND for such patients. The aim of this experimental pilot-feasibility study was to investigate whether visualization of retroperitoneal lymph nodes with patent blue violet (PBV) dye application is a feasible and an effective method during laparoscopic RPLND in a pig model. MATERIALS AND METHODS: Four 12-month-old white male pigs were included in the study. After PBV dye injection into the spermatic funicular and intratesticular parenchyma, the color changes in the retroperitoneal region were examined during transperitoneal laparoscopic visualization of the retroperitoneum. The time interval between the injection and the staining of lymphatic structures was measured for each intervention. Blue-stained retroperitoneal nodal tissues were dissected and removed by the laparoscopic approach and histologic examination was performed. RESULTS: After PBV dye injection, intense staining of the ipsilateral retroperitoneal lymphatic vessels and nodes was seen. Distribution of the PBV and the color changes of the retroperitoneal lymphatic structures were examined under laparoscopic vision in all pigs. All blue-stained retroperitoneal nodular tissues were removed laparoscopically and examined histologically. Histopathologic examination noted all specimens as lymph nodes with no toxic effects of PBV dye. CONCLUSION: We demonstrated that spermatic funicular injection of PVB dye is an effective and accurate method for retroperitoneal lymph node visualization in pigs. The use of this technique in combination with a laparoscopic approach makes RPLND easier and more effective.  相似文献   
8.
Progressive familial intrahepatic cholestasis (PFIC) is a cholestatic liver disease of childhood. Pruritus secondary to increased bile salts in the serum may not respond to medical treatment. Partial external biliary diversion (PEBD), which reduces the serum bile salt level in the enterohepatic cycle, is used in the treatment of this symptom. In this study, our experience in performing this technique and the early promising results of PEBD in two children with PFIC are reported along with a review of the current literature. Partial external biliary diversion was performed by interposing a 15-cm jejunum between the gallbladder and abdominal wall. Biliary drainage through a stoma began in the fi rst postoperative day and reached 120-200 ml/day. Pruritus improved and then stopped on the 15th postoperative day, while the serum bile acid concentration also decreased. Partial external biliary diversion by jejunal interposition provides an excellent control of pruritus in children with PFIC with no adverse effects. A cholecystectomy should therefore be avoided in patients with PFIC.  相似文献   
9.
Objective To investigate whether stone dimension is a restrictive factor for ureterorenoscopic procedures. Materials and methods A group of 416 patients who had undergone ureterorenoscopic pneumatic lithotripsy (URS-PL) for lower ureteral stones between January 1999 and June 2006 in our clinic had been evaluated retrospectively. Two hundred and seventy (270, 64.9%) patients were men and 146 (35.1%) were women. The mean age of the patients was 36.61 (±12.43) years. Patients were grouped according to stone dimension; 193 patients with stones smaller than 1 cm being group 1 and 223 patients with stones ≥1 cm in dimension being group 2. Stone-free rate, operative time and rate of complications of the groups were compared. Pearson’s correlation test, χ2 test, Fischer’s exact test and Student’s t-test were used for the statistical analysis. The p value was accepted as being meaningful if p < 0.05. Results For group 1, the mean operative time was 39.19 (±18.33) min. Proximal stone migration in five and false passage formation in three patients was observed. Three patients were stone-free after a second session of URS-PL. The cumulative stone-free rate was 97.4% (188/193). For group 2, the mean operative time was 48.5 (±11.31) min. About 208 (93.27%) patients were stone-free after the first session and an additional eight patients became stone-free after the second session of URS-PL. False passage, ureteral perforation, ureteral avulsion and stricture were observed in four, six, one and one patients, respectively. No proximal stone migration was observed. The cumulative stone-free rate was 96.86% (216/223). Conclusions The effectiveness of ureterorenoscopy (URS) in the treatment of distal ureteral stones was independent of stone dimension. However, the operative time was longer and the rate of perforation was higher in stones with a diameter ≥1 cm. On the other hand, the migration rate was higher in stones <1 cm in diameter. Generally speaking, there was no meaningful effect of stone dimension on complication rates.  相似文献   
10.
Background: Postoperative vomiting (POV) is a common complication after tonsillectomy. Dexamethasone is known to decrease postsurgical vomiting. In this study, we compared the effects of dexamethasone alone to dexamethasone plus propofol on postoperative vomiting in children undergoing tonsillectomy. Methods: In a randomized double‐blinded study, we evaluated 80 healthy children, aged 4–12 years, who underwent tonsillectomy with or without adenoidectomy. After anesthesia was induced by inhalation of sevoflurane, 0.15 mg·kg?1 dexamethasone and 2 μg·kg?1 fentanyl was administered i.v. to all patients. The patients in the dexamethasone plus propofol group received 1 mg·kg?1 propofol before intubation and continuously after intubation at a rate of 20 μg·kg?1·min?1 until the surgery was completed. Data for postoperative vomiting were grouped into the following time periods: 0–4 and 4–24 h. Data were analyzed using a Student’s t‐test and chi‐squared analysis. Results: The percentage of patients exhibiting a complete response (defined as no retching or vomiting for 24 h) increased from 37.5% in the dexamethasone‐alone group to 75% in the dexamethasone plus propofol group (P = 0.001). Twenty‐two patients (55%) in the dexamethasone‐alone and nine patients (22.5%) in the dexamethasone plus propofol groups experienced vomited during 0–4 h (P = 0.003). Eight patients in the dexamethasone‐alone group and three patients in the dexamethasone plus propofol group received ondansetron as a rescue antiemetic during the postoperative period. Conclusion: For children undergoing tonsillectomy, intraoperative subhypnotic propofol infusion combined with dexamethasone treatment provides a better prophylaxis against postoperative vomiting than does dexamethasone alone.  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