全文获取类型
收费全文 | 2428篇 |
免费 | 106篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 64篇 |
妇产科学 | 53篇 |
基础医学 | 281篇 |
口腔科学 | 86篇 |
临床医学 | 188篇 |
内科学 | 606篇 |
皮肤病学 | 17篇 |
神经病学 | 202篇 |
特种医学 | 278篇 |
外科学 | 270篇 |
综合类 | 34篇 |
一般理论 | 1篇 |
预防医学 | 221篇 |
眼科学 | 32篇 |
药学 | 126篇 |
中国医学 | 1篇 |
肿瘤学 | 76篇 |
出版年
2021年 | 33篇 |
2020年 | 14篇 |
2019年 | 27篇 |
2018年 | 42篇 |
2017年 | 26篇 |
2016年 | 25篇 |
2015年 | 26篇 |
2014年 | 57篇 |
2013年 | 79篇 |
2012年 | 94篇 |
2011年 | 114篇 |
2010年 | 91篇 |
2009年 | 84篇 |
2008年 | 119篇 |
2007年 | 110篇 |
2006年 | 81篇 |
2005年 | 89篇 |
2004年 | 93篇 |
2003年 | 85篇 |
2002年 | 78篇 |
2001年 | 95篇 |
2000年 | 103篇 |
1999年 | 97篇 |
1998年 | 45篇 |
1997年 | 64篇 |
1996年 | 58篇 |
1995年 | 42篇 |
1994年 | 42篇 |
1993年 | 49篇 |
1992年 | 43篇 |
1991年 | 45篇 |
1990年 | 45篇 |
1989年 | 51篇 |
1988年 | 40篇 |
1987年 | 35篇 |
1986年 | 43篇 |
1985年 | 38篇 |
1984年 | 23篇 |
1983年 | 12篇 |
1982年 | 20篇 |
1981年 | 10篇 |
1979年 | 17篇 |
1977年 | 19篇 |
1976年 | 17篇 |
1975年 | 17篇 |
1974年 | 12篇 |
1973年 | 13篇 |
1972年 | 9篇 |
1971年 | 10篇 |
1966年 | 9篇 |
排序方式: 共有2546条查询结果,搜索用时 46 毫秒
1.
D Gröne† R Treudler† EM de Villiers‡ R Husak† CE Orfanos† ChC Zouboulis†§ 《Journal of the European Academy of Dermatology and Venereology》2006,20(2):202-205
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment. 相似文献
2.
This study investigates the contribution of body fat stores on the age-associated increase in serum cholesterol and triglyceride levels. Percentage of body fat was measured by hydrostatic weighing, and serum cholesterol, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels were determined in a sample of 472 healthy men and women ages 18-50 years. In both sexes, body fat mass was significantly correlated with serum cholesterol (r = 0.21 in men and r = 0.24 in women, P less than 0.01) and triglyceride (r = 0.33 in men and r = 0.24 in women, P less than 0.01) levels. After adjustment for the association between age and serum cholesterol, no correlation was observed between body fat mass and serum cholesterol (r = 0.01 in men and r = 0.09 in women). After correction for age, serum triglyceride levels remained significantly correlated with body fat mass (r = 0.26 and r = 0.17 in men and women, respectively, P less than 0.05). As body fat also increases with age, the possibility that a partial correlation coefficient procedure eliminated a portion of the age effect mediated by an age-related increase in fat, was addressed by performing further analyses. Within each sex subsample two sets of analyses were performed on (a) three groups of subjects individually paired for age but with different levels of body fat stores, and (b) three groups of subjects paired for the amount of body fat but differing in age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
4.
5.
6.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
7.
8.
Transjugular intrahepatic portosystemic shunt before abdominal surgery in cirrhotic patients: a retrospective, comparative study. 总被引:1,自引:0,他引:1
Evelyne Vinet Pierre Perreault Louis Bouchard Denis Bernard Ramses Wassef Carole Richard Richard Létourneau Gilles Pomier-Layrargues 《Journal canadien de gastroenterologie》2006,20(6):401-404
Surgery in cirrhotic patients is associated with high morbidity and mortality related to portal hypertension and liver insufficiency. Therefore, preoperative portal decompression is a logical approach to facilitate abdominal surgery and hopefully to improve postoperative survival. The present study evaluated the clinical outcomes of 18 patients (mean age 58 years) with cirrhosis (seven alcoholics and 11 nonalcoholics) who underwent transjugular intrahepatic portosystemic shunt (TIPS) placement before antrectomy (n=5), colectomy (n=10), small-bowel resection (n=1), pancreatectomy (n=1) and nephrectomy (n=1). TIPS was performed a mean (+/-SD) of 72+/-21 days before surgery and induced a marked mean decrease in portohepatic gradient from 21.4+/-3.9 mmHg to 8.4+/-3.4 mmHg. Cirrhotic patients (n=17) who underwent elective abdominal surgery without preoperative TIPS placement were used as the control group. Both groups were matched for age, etiology of cirrhosis, indications for surgery, type of surgery and coagulation parameters. The mean Pugh score was significantly higher in the TIPS group (7.7 versus 6.2). No significant differences were observed for operative blood loss, postoperative complications, duration of hospitalization and one-month (83% versus 88%) or one-year (54% versus 63%) cumulative survival rate. Analysis using the Cox proportional hazards model showed that neither TIPS placement nor preoperative Pugh score were independent predictors for survival. The present study suggests that preoperative TIPS placement does not improve postoperative evolution after abdominal surgery in cirrhotic patients with good or moderately impaired liver function. 相似文献
9.
Perioperative antimicrobial prophylaxis (PAP) leads to a reduction in surgical site infections. The aim of PAP is adequate serum and tissue concentrations of the antimicrobial drug in the field of operation. The antibiotic must be effective against the expected pathogens during the operation, safe, and have the fewest possible side effects. The indication for PAP should take into account the risks of the operative procedure and especially the individual risk factors of the patient. Depending on pharmacokinetics, the antibiotic should be administered within 60 min before incision. After closure of the wound, further applications of the antibiotic drug have no influence on the infection rate of the wound but do increase the side effects (resistance, CDT colitis, allergy). Operation-specific recommendations according to guidelines of the Paul Ehrlich Society are given. 相似文献
10.
The preovulatory LH surge of the primate menstrual cycle represents a number of positive influences, a major component of which is a direct action of estradiol on the anterior pituitary lobe. Whether the LH surge also requires a corresponding burst of GnRH release from the hypothalamus has been debated. After many years of investigation, there is now conclusive evidence that a midcycle GnRH surge does occur in the primate. This is supported by studies in women with normal ovulatory cycles that demonstrate that blockade of the GnRH receptor by potent GnRH antagonists administered within 1-2 days of the expected midcycle can delay the LH surge. The ability to prevent the positive feedback effects of estradiol by GnRH antagonists is being employed for the controlled induction of follicular development and ovulation in the treatment of infertility and in in vitro fertilization programs. 相似文献