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   2097篇
  免费   71篇
  国内免费   12篇
耳鼻咽喉   28篇
儿科学   15篇
妇产科学   26篇
基础医学   194篇
口腔科学   32篇
临床医学   109篇
内科学   571篇
皮肤病学   58篇
神经病学   158篇
特种医学   103篇
外科学   361篇
综合类   17篇
预防医学   66篇
眼科学   3篇
药学   163篇
中国医学   4篇
肿瘤学   272篇
  2023年   13篇
  2022年   27篇
  2021年   70篇
  2020年   37篇
  2019年   36篇
  2018年   54篇
  2017年   47篇
  2016年   37篇
  2015年   39篇
  2014年   48篇
  2013年   59篇
  2012年   125篇
  2011年   157篇
  2010年   73篇
  2009年   70篇
  2008年   119篇
  2007年   163篇
  2006年   125篇
  2005年   138篇
  2004年   134篇
  2003年   122篇
  2002年   98篇
  2001年   23篇
  2000年   18篇
  1999年   20篇
  1998年   17篇
  1997年   28篇
  1996年   23篇
  1995年   18篇
  1994年   20篇
  1993年   17篇
  1992年   12篇
  1991年   15篇
  1990年   29篇
  1989年   26篇
  1988年   19篇
  1987年   22篇
  1986年   8篇
  1985年   5篇
  1984年   5篇
  1983年   6篇
  1982年   4篇
  1980年   4篇
  1979年   7篇
  1978年   8篇
  1977年   5篇
  1975年   8篇
  1974年   3篇
  1970年   5篇
  1968年   3篇
排序方式: 共有2180条查询结果,搜索用时 15 毫秒
91.
Growth hormone (GH) is known to accelerate spermatogenesis and maintain gonadal function. In this study, we evaluated the effect of GH on recovery from testicular damage induced by cyclophosphamide (CP). Eleven- to fourteen-week-old GH-deficient Lewis rats (dw/dw) were divided into 4 groups (n = 10 each), with one group serving as controls. In the CP group, CP was intravenously administered in daily doses of 50 mg/kg for 2 days, followed by daily doses of 10 mg/kg for the next 3 days. In the GH group, rat GH was subcutaneously administered at a daily dose of 0.3 mg/kg until the rats were sacrificed. In the CP/GH group, GH and CP administration were started simultaneously. In the CP/preGH group, GH administration was started 14 days before CP administration. Five rats from each group were sacrificed at days 14 and 28 after administration of CP. Spermatogenesis was then evaluated morphometrically by counting numbers of cells at several stages of the spermatogenic cycle. On day 14, there were no significant differences in the numbers of the spermatocytes between CP and CP/GH group. On day 28, the numbers of spermatocytes and motility of spermatozoa in CP/GH group were greater than those of CP group were. In the CP/preGH group, these effects of GH administration were not observed. These results suggested that administration of GH improved testicular function damaged by CP under GH-deficient condition, when GH and CP administration are started simultaneously.  相似文献   
92.
BACKGROUND: It is well known that aneurysms of the ophthalmic segment sometimes elevate the optic nerve or chiasm, and in case of large or giant aneurysms, the optic apparatus can be dramatically thinned. Nonetheless, they rarely penetrate the optic pathway completely. To our knowledge, no previous reports have dealt with the complete penetration of the optic chiasm by unruptured aneurysms of the ophthalmic segment. CASE DESCRIPTION: A 70-year-old woman presented with visual dysfunction in her left eye that she had experienced for several months. Her left visual acuity had rapidly deteriorated to the level of finger counting and visual field testing demonstrated nasal hemianopsia in the left eye and upper temporal quadrant hemianopsia in the right eye. Left internal carotid angiograms and three-dimensional digital subtraction angiograms showed an aneurysm of the ophthalmic segment projecting superomedially. Intraoperative findings revealed complete penetration of the optic chiasm by the fundus of the aneurysm. The optic pathway adjacent to the dome had become remarkably thin and dark yellow. After clipping was completed, the fundus of the aneurysm was punctured to decompress the optic chiasm. Postoperatively, patient's visual acuity in the left eye gradually recovered, but the visual field deficit persisted after the operation. CONCLUSION: This rare case demonstrates the potentially aggressive behavior of unruptured aneurysms of the ophthalmic segment. Patients with unruptured aneurysms of the ophthalmic segment who present with visual symptoms should be treated with surgical clipping to decompress the optic pathway as soon as possible.  相似文献   
93.
Aim: The present study was conducted to evaluate the effectiveness of early scheduled laparoscopic cholecystectomy (LC) following percutaneous transhepatic gallbladder drainage (PTGBD) for patients with acute cholecystitis. Patients and methods: 31 patients with acute cholecystitis were treated by early scheduled LC following PTGBD (group 1). These patients were compared with 9 patients treated by early LC without PTGBD (group 2) and with 12 patients treated by delayed LC following conservative therapy (group 3) for the success rate of intraoperative cholangiography, the conversion rate to open cholecystectomy, operative time, and hospital stay. Early scheduled LC following PTGBD was defined as scheduled LC when the patient's condition recovered and it was performed 1–7 days (mean: 4 days) after admission. The patients' age in group 1, 2, and 3 was 66 ± 13, 65 ± 10, and 64 ± 9 years, respectively, without significant difference. Most of the patients had additional diseases. Results: The success rate of intraoperative cholangiography was 97% (30/31) in group 1, 67% (6/9) in group 2, and 67% (8/12) in group 3. The conversion rate to open cholecystectomy was 3% (1/31) in group 1, 33% (3/9) in group 2, and 33% (4/12) in group 3. The operative time for LC was 89 ± 33 min in group 1, 116 ± 24 min in group 2, and 135 ± 30 min in group 3. The mean hospital stay after LC was 9 ± 4 days in group 1, 9 ± 3 days in group 2, and 17 ± 7 days in group 3. In group 1, the success rate of intraoperative cholangiography was higher, the conversion rate to open cholecystectomy was lower, and operative time was shorter than in groups 2 and 3 with significant difference (p <0.05, p <0.05, and p <0.01, respectively). Conclusion: The findings of this study indicate that early scheduled LC following PTGBD is a safe and effective therapeutic option for patients with acute cholecystitis especially in elderly and complicated patients.  相似文献   
94.
Skeletal muscle is able to repair itself through regeneration. However, an injured muscle often does not fully recover its strength because complete muscle regeneration is hindered by the development of fibrosis. Biological approaches to improve muscle healing by enhancing muscle regeneration and reducing the formation of fibrosis are being investigated. Previously, we have determined that insulin-like growth factor-1 (IGF-1) can improve muscle regeneration in injured muscle. We also have investigated the use of an antifibrotic agent, decorin, to reduce muscle fibrosis following injury. The aim of this study was to combine these two therapeutic methods in an attempt to develop a new biological approach to promote efficient healing and recovery of strength after muscle injuries. Our findings indicate that further improvement in the healing of muscle lacerations is attained histologically by the combined administration of IGF-1 to enhance muscle regeneration and decorin to reduce the formation of fibrosis. This improvement was not associated with improved responses to physiological testing, at least at the time-points tested in this study.  相似文献   
95.
Vestibular neuritis (VN) rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. We experienced 36 patients with VN treated at our hospital, including cases in our previous preliminary report. To elucidate effects of steroid therapy both on the recovery of peripheral function and on the adaptation of central vestibular compensation, we examined caloric test and several questionnaires with two randomly divided groups, 18 steroid-treated and 18 nonsteroid-treated patients, over two years after the onset. These examinations revealed that steroid-treated patients had a tendency of better canal improvements (13/18, 72%) than nonsteroid-treated ones (10/18, 55.6%). However, there was no significant difference between these two groups. In cases with persistent canal paresis, steroid-treated patients (n = 5) reduced handicaps in their everyday life due to the dizziness induced by head and/or body movements and the disturbance of their mood, more effectively than those with nonsteroid therapy (n = 8). These findings suggest that steroid therapy with VN could be effective on not only vestibular periphery but central vestibular system, to restore the balance.  相似文献   
96.
We report herein 2 patients with intractable postoperative bronchopleural fistula with empyema after lobectomy or subsegmentectomy. The patients underwent several treatments including thoracotomy, but the fistula closure was not successful. Finally, the bronchopleural fistula was successfully treated by endobronchial closureusing vascular occluding coils and n-butyl-2-cyanoacrylate (Histoacryl).  相似文献   
97.
Hydrogen peroxide is widely used for irrigation of surgical wounds. However, its administration has been associated with gas embolism. We report a case of gas embolism after wound irrigation with hydrogen peroxide in a 11-year-old boy undergoing extraction of the extra-traumatic splint under general anesthesia. When 3% hydrogen peroxide 12 ml was applied to wound of the left femur after extraction of the splint, the patient showed clinical signs of pulmonary embolism. Symptomatic treatment was initiated immediately. When the patient awoke from anesthesia, he showed tonic convulsion. But he recovered without any complications. The administration of hydrogen peroxide into a closed tissue is contraindicated during surgery.  相似文献   
98.
BACKGROUND: To determine whether the immunosuppressive acidic protein (IAP) could be a useful marker for renal cell carcinoma (RCC), serum IAP levels were compared with clinicopathological features in RCC patients. Furthermore, IAP cutoff level to predict the recurrence was determined using receiver operating characteristics (ROC) curve analysis. PATIENTS AND METHODS: Between January 1994 and December 1998, pretreatment serum IAP was measured in 123 consecutive patients with PCC at Kitasato University Hospital. Ninety-eight patients were received radical surgery and 86 patients were performed as clinically curable renal cell carcinoma (pT1-pT3N0M0). ROC curve analysis was utilized to set the cutoff value of IAP for prediction of cancer recurrence. Significance of prognostic factors in RCC recurrence was analyzed by Cox proportional hazard model. RESULTS: The mean age of the 123 patients was 58.6 years (range 33 to 90, median 59). The mean follow-up period was 24.8 months (range 1 to 78, median 26). The median IAP levels were 447 ug/ml in stage I, 629 ug/ml in stage II, 588 ug/ml in stage III and 1,150 ug/ml in stage IV (p < 0.05). Tumor size and venous involvement were significantly associated with IAP concentrations (p < 0.05). However, tumor grade did not correlate with IAP level. Of 86 patients with clinically curable tumor, 79 patients were disease-free after median follow-up of 27 months. Using ROC curve analysis, IAP cutoff level for prediction of cancer recurrence was set at 620 ug/ml. Disease-free survival rate in patients with preoperative IAP levels of 620 ug/ml or lower was 98.5% (67/68) at 27 months postoperatively, whereas that in patients with IAP greater than 620 ug/ml was 75.0% (12/18). This difference was statistically significant (p < 0.05). Results of multivariate analysis revealed that preoperative IAP and pT stage were statistically significant factors for tumor recurrence after radical surgery (p < 0.05). CONCLUSIONS: The present study indicates that preoperative IAP level is a useful prognostic marker in patients with RCC. In particular, patients with clinically curable tumors (pT1-3N0M0), whose preoperative IAP levels greater then 620 ug/ml may have high risk for recurrence after radical nephrectomy.  相似文献   
99.
A prospective randomized study involving gastric cancer patients was conducted to evaluate combined adjuvant chemotherapy. Forty-two patients under 80 years of age who underwent a curative resection of pathologic stage II or III gastric cancer were randomly assigned to receive adjuvant chemotherapy containing the following two regimens from 1993 to 1996. A) Oral 5'-deoxy-5-fluorouridin (5'-DFUR) plus cisplatin: 5'-DFUR, daily administration, combined with CDDP 15 mg/m2/day, 30-min drip infusion, fortnightly for 8 weeks, repeated every 16 weeks. B) Oral 5'-DFUR alone: 5'-DFUR, daily administration. The dosages of 5'-DFUR were assigned according to the patients' body surface area (BSA): BSA < 1.7 m2, 600 mg and BSA > or = 1.7 m2, 800 mg, daily administration, bid. Twenty patients were assigned to regimen A, and 22 to regimen B. All clinicopathological factors were equally distributed in each regimen. No adverse reactions greater than grade 3 occurred in either regimen. There was no significant difference between the two regimens in overall survival or overall disease-free survival. For patients with positive nodes, the 5-year disease-free survival rates were 56.4% in A and 38.3% in B (p = 0.29). In stage III patients, the 5-year disease-free survival rates were 55.6% in A and 20.7% in B (p = 0.26). No significant survival benefit was observed with the combined chemotherapeutic regimen, 5'-DFUR plus cisplatin, compared with 5'-DFUR alone.  相似文献   
100.
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