全文获取类型
收费全文 | 2230135篇 |
免费 | 182947篇 |
国内免费 | 4130篇 |
专业分类
耳鼻咽喉 | 31690篇 |
儿科学 | 71025篇 |
妇产科学 | 64545篇 |
基础医学 | 318912篇 |
口腔科学 | 66323篇 |
临床医学 | 197106篇 |
内科学 | 430909篇 |
皮肤病学 | 47077篇 |
神经病学 | 181509篇 |
特种医学 | 89643篇 |
外国民族医学 | 632篇 |
外科学 | 341668篇 |
综合类 | 58614篇 |
现状与发展 | 5篇 |
一般理论 | 767篇 |
预防医学 | 174265篇 |
眼科学 | 52298篇 |
药学 | 168218篇 |
3篇 | |
中国医学 | 4260篇 |
肿瘤学 | 117743篇 |
出版年
2018年 | 20501篇 |
2015年 | 20982篇 |
2014年 | 29270篇 |
2013年 | 44710篇 |
2012年 | 60325篇 |
2011年 | 63544篇 |
2010年 | 37418篇 |
2009年 | 35558篇 |
2008年 | 60559篇 |
2007年 | 64670篇 |
2006年 | 65123篇 |
2005年 | 63575篇 |
2004年 | 62567篇 |
2003年 | 59964篇 |
2002年 | 58424篇 |
2001年 | 99585篇 |
2000年 | 102586篇 |
1999年 | 87140篇 |
1998年 | 24706篇 |
1997年 | 22594篇 |
1996年 | 22464篇 |
1995年 | 21684篇 |
1994年 | 20487篇 |
1993年 | 19264篇 |
1992年 | 72669篇 |
1991年 | 70587篇 |
1990年 | 69105篇 |
1989年 | 66762篇 |
1988年 | 62461篇 |
1987年 | 61470篇 |
1986年 | 58467篇 |
1985年 | 56588篇 |
1984年 | 42911篇 |
1983年 | 36907篇 |
1982年 | 22505篇 |
1981年 | 20319篇 |
1980年 | 18980篇 |
1979年 | 41991篇 |
1978年 | 29633篇 |
1977年 | 24968篇 |
1976年 | 23294篇 |
1975年 | 24855篇 |
1974年 | 30641篇 |
1973年 | 29386篇 |
1972年 | 27285篇 |
1971年 | 25716篇 |
1970年 | 23878篇 |
1969年 | 22738篇 |
1968年 | 20645篇 |
1967年 | 18848篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
J M Ragnaud H Gin P Tauzin-Fin P Ballanger R Ballanger J Aubertin 《Pathologie-biologie》1983,31(5):434-437
The main point of this study resides in comparing the efficiency and the disadvantages of using cefazoline and cotrimoxazole in the prevention of post-surgery infections of the low urinary tract. 91 patients who were about to undergo urologic surgery were divided in three groups for randomisation. 31 patients received 500 mg of intramuscular cefazoline every eight hours, the day before surgery, the day of surgery and five days following surgery. 30 others received 800 mg of intramuscular sulfametoxazole and 160 mg of trimetoprime every 12 hours during the same lapse of time. The third group of 30 patients did not receive any antibiotics. Age, sex, clinical pathology needing surgery and indwelling catheter were the same in the three groups. The group treated by cefazoline, presented 5 post surgery infections among which 3 transitory fevers and 2 isolated bacteriurias. In the group treated by cotrimoxazole, there were 7 post surgery infections among which 3 fevers and 4 isolated bacteriurias. Tolerance in both cases was similar. In the control group, there were 19 post-surgery infections with 2 cases of sepsis, 14 transitory fevers and 3 isolated bacteriurias. These results show the importance of antibiotic prophylaxy in urologic surgery of the low genital tract whether the patient has a urethral catheter or not and whatever the type of urologic surgery. But, there is no significant difference between cefazoline and cotrimoxazole. 相似文献
982.
A practice audit of oral contraceptive users 总被引:1,自引:0,他引:1
W Reith 《British medical journal (Clinical research ed.)》1983,287(6389):401-402
983.
Abra R. M. Hunt C. Anthony Fu K. K. Peters J. H. 《Cancer chemotherapy and pharmacology》1983,11(2):98-101
Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst... 相似文献
984.
985.
Summary In cases where a reconstruction of defects in the larynx, oral cavity, the pharynx or in the ear region has been performed using skin flaps, a temporary fistula is formed at the point of entry.This fistula can be closed later after the flap has taken and the flap pedicle dissected.We would like to demonstrate with some examples that with the use of deepithelisation it is possible to achieve a primary wound closure. This way no temporary fistula results and additional surgery is avoided in many cases.Furthermore flap deepithelisation offers a way to bring good vascularised tissue under the skin and cover subcutaneous defects, for example those after radiotherapy.
Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen 相似文献
Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen 相似文献
986.
G B Hopkinson D A Woodward N Prasad B R Bullen 《Annals of the Royal College of Surgeons of England》1983,65(5):323-324
The presence of accessory channels between the liver and extrahepatic bile ducts has long been recognised by anatomists and the division of such ducts may be a cause of bile leakage following cholecystectomy. However, visualisation of accessory bile ducts at operation is difficult as they are often small and sometimes less than 1 mm in diameter. Cholangiography has been used to help in the identification of accessory ducts in 50 patients included in a prospective trial. X-rays were taken after dissection of the gall bladder from its bed and extravasation of contrast was seen on five occasions (10%) suggesting leakage from divided accessory ducts. The identification of damage to accessory bile ducts in 10% of patients suggests that this may occur more frequently than previously supposed. 相似文献
987.
W M Kluwe 《Journal of applied toxicology : JAT》1983,3(4):167-174
The organ-specific toxic potency of subcutaneously administered 1,2-dibromo-3-chloropropane (DBCP) was compared in partially hepatectomized and sham-operated rats over a dose range of 20--80 mg kg-1 to assess the roles of hepatic and extrahepatic metabolism in protection against acute renal and gonadal injury. Relative kidney weight and the severity of DBCP-induced renal proximal tubular cell necrosis were increased in rats subjected to a partial (70%) surgical hepatectomy 48 h prior to treatment with DBCP at 80 mg kg-1. Relative liver weight was reduced by DBCP in the hepatectomized, but not in the sham-operated rats. The severity of DBCP-induced (80 mg kg-1) hepatocellular centrilobular necrosis was greater in hepatectomized than in sham rats. DBCP reduced the relative weights of the testis and epididymis in a progressive manner and produced dose-dependent seminiferous tubular atrophy within 12 days of treatment. The morphologically apparent lesions of the testis and epididymis were enhanced by hepatectomy. The concentration of non-protein sulfhydryl groups (NPS) in rat liver was increased by partial hepatectomy. Because of the resulting decrease in liver size, however, the total amount of hepatic NPS per kg body weight 48 h post-surgery was lower than in sham rats. The surgery had no effect on renal, testicular or epididymal NPS concentrations of organ weights. Partial hepatectomy greatly increased pentobarbital and ethanol sleeping times, while sleep induction time for pentobarbital was decreased.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
988.
Hemangioma of the nasal vault: MR and CT features 总被引:1,自引:0,他引:1
Six patients with a history of epistaxis (five patients) or nasal obstruction (one patient) were found to have a capillary hemangioma of the nasal vault that involved one or more nasal turbinates. Four patients underwent computed tomographic (CT) examination; two of these also underwent magnetic resonance (MR) imaging. Four others underwent only MR imaging. At CT and MR, all of the lesions were well circumscribed and intensely enhancing, with contralateral deviation of the nasal septum. Remodeling of the surrounding bone was present in three patients. On T1-weighted MR images, the masses were intermediate in signal intensity. Varying degrees of T2 shortening were shown on T2-weighted MR images, with an appearance that suggested the presence of blood products surrounding an inner matrix of higher-signal-intensity tumor. Intense enhancement at CT and MR assisted differentiation of tumor from retained sinonasal secretions. In two patients, external carotid arteriography revealed small foci of pooling contrast material; in one of these patients, arteriovenous shunting was also present. Pathologic examination in all patients demonstrated capillary hemangiomas with varying degrees of fibrosis and hemosiderin deposition. 相似文献
989.
990.
W L Sanvito 《Arquivos de neuro-psiquiatria》1991,49(3):243-250
It is stressed that the brain/mind complex constitutes a monolithic system that functions with emergent properties at several levels of hierarchical organization. These hierarchical levels are non-reducible to one another; they are at least three (neuronal, functional, and semantic), and they function within an interactional plan. From the epistemological view-point, the brain/mind complex uses logical and non-logical mechanisms to deal with day-to-day problems. Logic is necessary for the thinking process, but it is not sufficient. Emphasis is given to non-logical mechanisms; fuzzy logic and heuristics, which allow the mind to develop strategies to find solutions, are analysed. 相似文献