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   1318篇
  免费   54篇
  国内免费   11篇
耳鼻咽喉   3篇
儿科学   47篇
妇产科学   23篇
基础医学   130篇
口腔科学   10篇
临床医学   87篇
内科学   160篇
皮肤病学   35篇
神经病学   43篇
特种医学   133篇
外科学   197篇
综合类   269篇
一般理论   1篇
预防医学   84篇
眼科学   4篇
药学   52篇
肿瘤学   105篇
  2022年   5篇
  2021年   11篇
  2020年   8篇
  2019年   11篇
  2018年   15篇
  2017年   19篇
  2016年   12篇
  2015年   38篇
  2014年   25篇
  2013年   50篇
  2012年   44篇
  2011年   41篇
  2010年   60篇
  2009年   51篇
  2008年   63篇
  2007年   65篇
  2006年   88篇
  2005年   63篇
  2004年   70篇
  2003年   39篇
  2002年   44篇
  2001年   26篇
  2000年   25篇
  1999年   39篇
  1998年   45篇
  1997年   56篇
  1996年   55篇
  1995年   33篇
  1994年   30篇
  1993年   11篇
  1992年   10篇
  1991年   11篇
  1990年   12篇
  1989年   11篇
  1988年   22篇
  1987年   16篇
  1986年   14篇
  1985年   17篇
  1984年   13篇
  1983年   5篇
  1982年   8篇
  1981年   8篇
  1980年   5篇
  1977年   5篇
  1976年   6篇
  1975年   6篇
  1972年   5篇
  1970年   6篇
  1969年   6篇
  1966年   6篇
排序方式: 共有1383条查询结果,搜索用时 453 毫秒
91.
1. Magnolol is an active component of Magnolia officinalis. It is 1000-times more potent than α-tocopherol in inhibiting lipid peroxidation in rat heart mitochondira. In the present study, the in vivo antiarrhythmic and anti-ischaemic effects of magnolol in coronary ligated rats were investigated. 2. Male Sprague-Dawley rats were anaesthetized with urethane. Magnolol, at dosages of 10?7, 10?8 and 10?9 g/kg, was adminstered intravenously 15 min before ligation of the coronary artery. 3. The incidence and duration of ventricular tachycardia and ventricular fibrillation during 30 min coronary ligation were significantly reduced by magnolol. Ventricular arrhythmias during 10 min reperfusion after the relief of coronary ligation were also reduced. 4. In rats subjected to 4h coronary ligation, 10?7 and 10?8 g/kg magnolol significantly reduced infarct size. 5. We conclude that magnolol may protect the myocardium against ischaemic injury and suppress ventricular arrhythmia during ischaemia and reperfusion.  相似文献   
92.
93.

Background

In view of increase in incidence of exptrapulmonary tuberculosis after the epidemic of human immunodeficiency virus infection, the clinical profile of extrapulmonary tuberculosis in patients with HIV infection was studied.

Method

The study population comprised patients of HIV infection with extrapulmonary tuberculosis. Work up included history, clinical examination, sputum for acid fast bacilli, chext X-ray, ultrasonography (USG) abdomen, fine needle aspiration cytology(FNAC), transbronchial needle aspiration (TBNA) and computed tomography of chest.

Results

There were 50 cases, all males with mean age of 35 years. 24(48%) were without pulmonary tuberculosis and 26(52%) had pulmonary tuberculosis. 41(82%) had disseminated disease and 9(18%) involve one site. Fever and weight loss were the most frequent symptoms (79% and 58% respectively) in cases without pulmonary tuberculosis. The most frequent extrapulmonary site was lymph node in 46(92%), followed by spleen in 13(26%), pleura 9(18%), miliary 7(14%) and hepatic 1(2%). The diagnosis was confirmed by invasive methods in 30 out of 50(60%) cases [FNAC in 23(88%), TBNA in 2(25%) and pleural biopsy in 5(55%)].

Conclusion

In HIV infected patients, the most common extrapulmonary site is lymph mode followed by spleen.Key Words: Extrapulmonary TB, HIV Infection  相似文献   
94.
PURPOSE: Recent data support the role of androgen deprivation in men undergoing external beam radiotherapy for prostate cancer. The benefits of neoadjuvant, concurrent or adjuvant treatment have been limited to men at intermediate and high risk. We examined the patterns and predictors of androgen deprivation in men undergoing external beam radiation therapy in CaPSURE. MATERIALS AND METHODS: CaPSURE is an observational, longitudinal disease registry, from which 932 men met study inclusion criteria. Androgen deprivation was classified as neoadjuvant-within 9 months of radiation or adjuvant-from the start of radiation to 6 months after completion. Time trends in androgen deprivation as well factors associated with combined therapy were elucidated using multivariate analyses. RESULTS: In this study 40%, 39% and 21% of men could be categorized into high, intermediate and low risk groups, respectively. Overall 42% and 33% of patients received neoadjuvant and adjuvant androgen deprivation therapy, respectively. Between 1997 and 2002 neoadjuvant hormone use increased significantly in all risk groups, including patients at low risk. On multivariate analyses only the year of diagnosis and clinical risk group were associated with receiving androgen deprivation with radiation. CONCLUSIONS: A significant increase in combined androgen deprivation and external radiation was observed in the last decade in men with intermediate and high risk disease. Nevertheless, more widespread acceptance is necessary since a substantial minority continue to receive radiation alone. Many patients with low risk disease that is amenable to radiation monotherapy also receive androgen deprivation. No clinical or sociodemographic features predicted the use of androgen deprivation with external radiation.  相似文献   
95.
The effects of glucocorticoids on cancellous bone remodeling and structure are well documented but there are no reported histomorphometric studies in human cortical bone in glucocorticoid-treated patients. We have performed a histomorphometric analysis of iliac crest cortical bone in 14 patients treated with glucocorticoids, 9 females and 5 males, aged 18 to 48 years (34.1 ± 7 years) (mean ± standard deviation [SD]). The underlying disease was cystic fibrosis in 8 patients; asthma 3; and nephrotic syndrome; Crohn disease and inflammatory pseudotumor of the liver in one patient each. Results were compared with an age-matched control group of 10 premenopausal women and 4 men aged 22 to 38 years (30.1 ± 4.8 years) who were not, howerver matched for underlying disease. Cortical bone indices were assessed by image analysis. Cortical width and area were similar in the two groups. However, cortical porosity, Haversian canal number, and density were higher in patients treated with glucocorticoids compared with controls (8.4 ± 8.9% vs. 5.1 ± 3.9%; P = 0.03) (45.9 ± 23.2 vs. 31.9 ± 24.4; P =0.003) (13.7 ± 9.4 vs. 6.7 ± 3.3/mm2; P = 0.00005). Haversian canal area did not differ significantly between groups. The mean wall width of the osteons, bone formation rate (μm2/μm/day) and mineral apposition rate (μm/day) were lower in treated patients compared to controls (48.8 ± 7.1 μm vs. 59.8 ± 12.9 μm; P = 0.01) (0.056 ± 0.040 vs. 0.095 ± 0.058; P = 0.05) and (0.59 ± 0.12 vs. 0.75 ± 0.11; P = 0.002). The proportion of canals with an eroded surface was lower in the treated compared with the control group, although this difference was not statistically significant. These results demonstrate that cortical porosity is increased in patients treated with long-term glucocorticoid therapy, due mainly to an increase in the number rather than size of Haversian canals. This may be because of increased bone resorption during the early stages of glucocorticoid therapy, in combination with long-term impairment of bone formation. Effects of the underlying disease on bone remodeling may also contributed to these changes and could not be excluded in the present study; since control subjects were not matched in terms of disease status.  相似文献   
96.
97.
HYPOTHESIS: Laparoscopic approaches for weight reduction in the morbidly obese have become common with more than 50,000 bariatric surgical procedures being performed in 2001. The objective of this article is to raise awareness among surgeons of a new complication of rhabdomyolysis from this frequent procedure. DESIGN: Case series extracted from surgical database from January 2, 2001, through December 31, 2002. PATIENTS AND METHODS: We identified 5 cases of postoperative rhabdomyolysis in morbidly obese patients who underwent laparoscopic duodenal switch procedures with parietal gastrectomy. The cause, pathogenesis, and clinical features are reviewed and discussed. RESULTS: Postoperative rhabdomyolysis developed in 5 of 353 morbidly obese patients who underwent consecutive laparoscopic duodenal switch procedures, an incidence of 1.4%. All 5 patients were male, had a mean peak serum creatine kinase level of 19 680 U/L, and reported muscle pain in either the buttock, hip, or shoulder regions during the early postoperative period. CONCLUSIONS: We hypothesized that morbidly obese patients develop critical surface and deep tissue pressures during bariatric surgery, increasing their risk for tissue injury and rhabdomyolysis. Unexplained elevations in the serum creatinine level or reports of buttock, hip, or shoulder pain in the postoperative period should raise the possibility of rhabdomyolysis and prompt clinical investigation. We recommend routine preoperative and postoperative measurements of the serum creatine kinase and serum creatinine levels to aid detection. Surgeons need to keep a low index of suspicion because early diagnosis and treatment are the cornerstones of successful management of rhabdomyolysis.  相似文献   
98.
There are varied indications of preserving a semen sample for utilization at a later day. However, the freeze-thaw cycle is bound to impart deleterious effect on the fertilizing potential of the sample. 60 semen samples divided into three groups were preserved in this study. On subsequent thawing, after three months it was seen that the yield varied between 66% to 72%. The post thaw percent yield bears a linear relationship with the pre-freeze quality. 5 pregnancies were achieved in the study testifying the preservation of fertilizing ability of the thawed samples. Sub normal semen samples which might be otherwise acceptable in a therapeutic insemination, do not withstand freezing.Key Words: Cryopreservation, Semen  相似文献   
99.
A total of 50 patients undergoing cancer treatment at Malignant Disease Treatment Centre were included in the present study aimed at evaluating the psychological status of cancer patients. All patients filled a specially designed proforma and the following psychological questionnaires : General Health Questionnaire, Carroll Rating Scale for Depression, State-Trait Anxiety Inventory, PGI General Well-being Scale and Quality of Life Scale. Analysis of the results showed that 22 (44%) of the cancer patients had psychiatric disorders and this number had reduced to 12 (24%) after therapy. The difference was statistically significant. Psychiatric treatment also resulted in a statistically significant reduction in level of depression as measured by Carroll Rating Scale for depression. Short term psychiatric treatment was found to be very useful in treating psychiatric morbidity and depression in cancer patients.Key Words: Cancer, Depression, Psychiatric morbidity  相似文献   
100.
Retrospective study of 121 cases of adnexal masses which were managed laparoscopically was carried out. The aim of study was to evaluate the safety and effectiveness of laparoscopic management of adnexal masses. In 120 cases, procedure was completed safely with minimum morbidity. In one case laparotomy had to be done to complete the procedure. In 76 cases cystectomy was done, 26 required salpingo-oophorectomy and 19 required only salpingectomy. Histologic evaluation revealed 30 functional cysts, 36 endometriotic cysts, 11 dermoids, 9 serous cystadenomas, 3 mucinous cystadenomas, 11 parovarian cysts, 19 cases of hydrosalpinx and 2 cases of tuberculosis.Key Words: Adnexal mass, Laparoscopy, Ovarian cyst  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