全文获取类型
收费全文 | 3931597篇 |
免费 | 293313篇 |
国内免费 | 6746篇 |
专业分类
耳鼻咽喉 | 56449篇 |
儿科学 | 124530篇 |
妇产科学 | 105549篇 |
基础医学 | 565483篇 |
口腔科学 | 112418篇 |
临床医学 | 361370篇 |
内科学 | 750916篇 |
皮肤病学 | 83431篇 |
神经病学 | 319620篇 |
特种医学 | 151399篇 |
外国民族医学 | 1277篇 |
外科学 | 590620篇 |
综合类 | 89551篇 |
现状与发展 | 13篇 |
一般理论 | 1602篇 |
预防医学 | 317547篇 |
眼科学 | 93853篇 |
药学 | 294188篇 |
14篇 | |
中国医学 | 7545篇 |
肿瘤学 | 204281篇 |
出版年
2018年 | 42190篇 |
2017年 | 32011篇 |
2016年 | 35702篇 |
2015年 | 40333篇 |
2014年 | 57680篇 |
2013年 | 87763篇 |
2012年 | 119320篇 |
2011年 | 126851篇 |
2010年 | 75459篇 |
2009年 | 71425篇 |
2008年 | 119440篇 |
2007年 | 127250篇 |
2006年 | 128497篇 |
2005年 | 124885篇 |
2004年 | 120129篇 |
2003年 | 115586篇 |
2002年 | 113215篇 |
2001年 | 175060篇 |
2000年 | 180561篇 |
1999年 | 152789篇 |
1998年 | 45600篇 |
1997年 | 40443篇 |
1996年 | 40030篇 |
1995年 | 38337篇 |
1994年 | 35735篇 |
1993年 | 33551篇 |
1992年 | 121596篇 |
1991年 | 118634篇 |
1990年 | 115298篇 |
1989年 | 111058篇 |
1988年 | 102940篇 |
1987年 | 101088篇 |
1986年 | 95441篇 |
1985年 | 91703篇 |
1984年 | 69256篇 |
1983年 | 59102篇 |
1982年 | 35808篇 |
1981年 | 32057篇 |
1979年 | 64965篇 |
1978年 | 46081篇 |
1977年 | 38670篇 |
1976年 | 36879篇 |
1975年 | 39078篇 |
1974年 | 47659篇 |
1973年 | 45371篇 |
1972年 | 42878篇 |
1971年 | 40123篇 |
1970年 | 37360篇 |
1969年 | 35159篇 |
1968年 | 32291篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
951.
Postoperative sagittal sinus thrombosis after spinal anesthesia 总被引:2,自引:0,他引:2
952.
V K Ryzhkov N A Borisova E M Gapchenko I A Dmitrieva 《Vestnik khirurgii imeni I. I. Grekova》1986,136(1):11-14
Roentgen endovascular occlusion with spiral emboli was used in 240 patients with different diseases. The introduction of spiral emboli into the arteries of abdominal and retroperitoneal organs was fulfilled through usual angiographic catheters. Duration of the arterial occlusion was checked up in the following angiographic examinations and showed the devices described to be appropriate for a continuous arterial blockade. No complications resulting from the introduction of the spiral embolus were noted. 相似文献
953.
The multiple regression analysis of twin data in which a cotwin's score is predicted from that of a proband (the member of a twin pair selected because of a deviant score) and the coefficient of relationship provides a powerful test of genetic etiology (DeFries and Fulker: Behav Genet 15:467-473, 1985). Moreover, when an augmented model containing an interaction term is fitted to the same data set, direct estimates of heritability (h2) and the proportion of variance owing to shared environmental influences (c2) are also obtained. In the present paper, the expected partial regression coefficients estimated from these models are derived, and the flexibility of the general approach is illustrated. An extended model is formulated for the analysis of data from combined samples of affected and control twin pairs that yields tests for differential h2 and c2 in the two groups as well as pooled estimates of these parameters. The application of these models is illustrated by an analysis of data from reading-disabled and control twin pairs. Because of the ease, flexibility, and utility of the multiple regression analysis of twin data, it is an appealing alternative to more traditional model-fitting approaches. 相似文献
954.
955.
H J Keene 《Journal of dental research》1986,65(6):935-938
We examined the skeletal remains of 1338 early Hawaiians (preserved in the Bishop Museum, Honolulu) to determine total caries and root surface caries prevalence. Specimens from seven islands were represented in the collection. Estimation of age at death was made by a combination of dental developmental staging for younger individuals and occlusal attrition and/or alveolar bone loss in adults. Museum records were also consulted for age estimation of adults which was primarily based on osteological criteria. The material was divided into six age groups. Predentate infants and edentulous adults were not included. A total of 19,425 teeth was examined. Caries lesions were observed in 462 individuals (34.5%) and 1895 teeth (9.8%). Coronal caries lesions in children and adolescents tended to be small and not particularly destructive of tooth structure. Root surface lesions in young adults were also small but increased progressively in size in the older groups, resulting in pulp exposure and coronal amputation. Although coronal caries was apparently not a significant dental health problem in children and young adults (compared with contemporary Hawaiians), root surface caries was an increasingly important source of tooth morbidity and tooth mortality in the older population groups. This age-related caries pattern was similar for all of the islands. 相似文献
956.
H Atlan R Sigal H Hadar R Chisin I Cohen A Lanir M Soudry Y Machtey R Schreiber J Benmair 《Journal of nuclear medicine》1986,27(2):207-215
Thirty-two patients with diversified pathology were examined with a supraconductive NMR imager using spin echo with different TR and TE to obtain T1 and T2 weighted images. They included 20 tumors (12 primary, eight metastasis), six osteomyelitis, three fractures, two osteonecrosis, and one diffuse metabolic (Gaucher) disease. In all cases except for the stress fractures, the bone pathology was clearly visualized in spite of the normal lack of signal from the compact cortical bone. Nuclear magnetic resonance (NMR) imaging proved to be at least as sensitive as radionuclide scintigraphy but much more accurate than all other imaging procedures including computed tomography (CT) and angiography to assess the extension of the lesions, especially in tumors extended to soft tissue. This is due both to easy acquisition of sagittal and coronal sections and to different patterns of pathologic modifications of T1 and T2 which are beginning to be defined. It is hoped that more experience in clinical use of these patterns will help to discriminate between tumor extension and soft-tissue edema. We conclude that while radionuclide scintigraphy will probably remain the most sensitive and easy to perform screening test for bone pathology, NMR imaging, among noninvasive diagnostic procedures, appears to be at least as specific as CT. In addition, where the extension of the lesions is concerned, NMR imaging is much more informative than CT. In pathology of the spine, the easy visualization of the spinal cord should decrease the need for myelography. 相似文献
957.
Metoclopramide, a substituted benzamide derivative, was orally administered to a patient with intractable hiccups. Dysphoria, akathisia, depressed mood with suicidal ideation, insomnia, racing thoughts, and labile affect were seen following the administration of metoclopramide. The episode met criteria for an organic affective syndrome. It is suggested that the mental status of patients undergoing metoclopramide therapy be monitored, since these symptoms have not been previously reported. 相似文献
958.
Horner's syndrome or oculosympathetic paralysis is not an uncommon finding in patients with head and neck neoplasms. While in most cases the syndrome is easily established at the bedside, it can be confirmed and topographically defined as a central, preganglionic, or postganglionic lesion through sequential pharmacologic testing. The importance of such localization lies in differentiating neoplasia vs. a benign condition as the cause of the syndrome. Such variants as congenital Horner's, an alternating Horner's, and a pseudo-Horner's syndrome are discussed in regard to their differential features. 相似文献
959.
Diaper area skin microflora of normal children and children with atopic dermatitis. 总被引:1,自引:1,他引:0 下载免费PDF全文
In vitro studies established that neither cloth nor disposable diapers demonstrably contributed to the growth of Escherichia coli, Proteus vulgaris, Staphylococcus aureus, or Candida albicans when urine was present as a growth medium. In a clinical study of 166 children, the microbial skin flora of children with atopic dermatitis was compared with the flora of children with normal skin to determine the influence of diaper type. No biologically significant differences were detected between groups wearing disposable or cloth diapers in terms of frequency of isolation or log mean recovery of selected skin flora. Repeated isolation of S. aureus correlated with atopic dermatitis. The log mean recovery of S. aureus was higher in the atopic groups. The effects of each diaper type on skin microflora were equivalent in the normal and atopic populations. 相似文献
960.
A. Jaén J. Sunyer X. Basagaña S. Chinn† J. P. Zock J. M. Antó‡ P. Burney† 《Clinical and experimental allergy》2002,32(12):1713-1719
BACKGROUND: The role of atopy in the evolution to chronic obstructive disease remains controversial. AIM: We aimed to assess the association between individual sensitization to common allergens and lung function. METHOD: We analysed data from 12,687 subjects aged 20 to 44 years, from 34 centres in 15 countries participating in the European Community Respiratory Health Survey (ECRHS). Participants performed a blood test, lung function test, methacholine challenge, and answered an administered questionnaire. The relationships between specific IgE, FEV1 and FEV1/FVC ratio were assessed for each study centre stratified by sex, followed by random effects meta-analysis. RESULTS: Asthmatics sensitized to house dust mite had a lower FEV1 (-119 mL in women and -112 mL in men) and FEV1/FVC ratio (-1.95%, and -2.48%) than asthmatics without sensitization. Asthmatics sensitized to cat had a lower FEV1 (statistically significant for women only) and a lower FEV1/FVC ratio. Asthmatic women sensitized to grass had a lower FEV1 and a lower ratio, and those sensitized to Cladosporium had a lower FEV1. A weak association was found with sensitization to cat and to Cladosporium among non-asthmatic women, which disappeared after adjusting for BHR. CONCLUSION: We conclude that atopy was related to a lower lung function, which was only apparent among asthmatics. This relationship was explained by specific sensitization to cat and to house dust mite, the latter being homogeneous across areas. 相似文献