全文获取类型
收费全文 | 2370837篇 |
免费 | 172147篇 |
国内免费 | 4280篇 |
专业分类
耳鼻咽喉 | 33496篇 |
儿科学 | 74246篇 |
妇产科学 | 67455篇 |
基础医学 | 342261篇 |
口腔科学 | 69134篇 |
临床医学 | 212007篇 |
内科学 | 459909篇 |
皮肤病学 | 52680篇 |
神经病学 | 189728篇 |
特种医学 | 90961篇 |
外国民族医学 | 676篇 |
外科学 | 353298篇 |
综合类 | 52420篇 |
现状与发展 | 8篇 |
一般理论 | 957篇 |
预防医学 | 181288篇 |
眼科学 | 55197篇 |
药学 | 177070篇 |
10篇 | |
中国医学 | 4683篇 |
肿瘤学 | 129780篇 |
出版年
2018年 | 23073篇 |
2016年 | 19880篇 |
2015年 | 22730篇 |
2014年 | 31586篇 |
2013年 | 48451篇 |
2012年 | 64553篇 |
2011年 | 68586篇 |
2010年 | 40319篇 |
2009年 | 38858篇 |
2008年 | 65402篇 |
2007年 | 70620篇 |
2006年 | 70840篇 |
2005年 | 68925篇 |
2004年 | 66713篇 |
2003年 | 64183篇 |
2002年 | 62783篇 |
2001年 | 107354篇 |
2000年 | 109835篇 |
1999年 | 92988篇 |
1998年 | 25714篇 |
1997年 | 23382篇 |
1996年 | 23211篇 |
1995年 | 21864篇 |
1994年 | 20500篇 |
1992年 | 73086篇 |
1991年 | 71419篇 |
1990年 | 69660篇 |
1989年 | 67938篇 |
1988年 | 63132篇 |
1987年 | 62055篇 |
1986年 | 59514篇 |
1985年 | 56208篇 |
1984年 | 42533篇 |
1983年 | 36584篇 |
1982年 | 21871篇 |
1981年 | 19892篇 |
1979年 | 40743篇 |
1978年 | 29503篇 |
1977年 | 25106篇 |
1976年 | 23141篇 |
1975年 | 25654篇 |
1974年 | 30769篇 |
1973年 | 30118篇 |
1972年 | 28801篇 |
1971年 | 26858篇 |
1970年 | 25411篇 |
1969年 | 24314篇 |
1968年 | 22714篇 |
1967年 | 20443篇 |
1966年 | 19219篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
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
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
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
992.
993.
Donor interleukin-4 promoter gene polymorphism influences allograft rejection after heart transplantation. 总被引:3,自引:0,他引:3
Femke J Bijlsma Joyce vanKuik Marcel G J Tilanus Nicolaas deJonge Erik H Rozemuller Jan G van den Tweel Frits H J Gmelig-Meyling Roel A deWeger 《The Journal of heart and lung transplantation》2002,21(3):340-346
BACKGROUND: The cytokine interleukin-4 (IL-4) is secreted mainly by activated T lymphocytes and characterizes the T-helper 2 (Th2) sub-type. In transplantation Th2 cells are believed to induce graft tolerance. Previous studies revealed that patients with a relatively high frequency of IL-4 producing helper T lymphocytes (HTL) before heart transplantation (HTX) had no or less rejection episodes compared with patients with a low frequency of IL-4 producing HTL. Three single nucleotide polymorphisms (SNPs) have been identified in the promoter region of the IL-4 gene, which influence promoter strength. We investigated whether there was a correlation between SNP genotypes in the IL-4 promoter and heart failure, and rejection after HTX. METHODS: Seventy HTX patients, 61 donors, and 36 controls were genotyped for the 3 SNPs by sequencing. RESULTS: Of the SNPs at -285 and -81, only the C and A alleles, respectively, were found in this study. Both alleles were found for the -590 SNP. No relation between patient genotype of the SNP at -590 and heart failure and rejection was found. However, incidence of rejection was significantly lower in patients that received a donor heart with the T-positive genotype compared with patients that received a heart from a T-negative donor. Patients who had the T-negative genotype and received a heart from a T-positive donor, suffered significantly less from rejection than T-negative patients that received a T-negative donor heart. This was not significant in the T-positive patient group. CONCLUSIONS: This indicates that IL-4 production within the donor heart and by cells from the donor is important for reducing incidence of episodes of rejection. 相似文献
994.
995.
H. Draper 《Journal of Renal Care》2002,28(Z2):39-42
The majority of patients being treated for acute renal failure in intensive care units have multiple medical problems. Accordingly, the withdrawal of renal replacement therapies should be considered as part of a general decision about whether to initiate or continue with treatment per se. Several guidelines on withdrawing and withholding therapy have been produced and some common themes emerge: concerns to avoid euthanasia, potential for benefit, patient consent (shared decision‐making), team consensus/decision‐making, and the provision of appropriate palliative care and resource implications. Each of these is considered in turn, although the word limit for this paper does not permit detailed exposition. 相似文献
996.
C. Sch?fer H. H. Klünemann B. Ibach J. Mueller A. Putzhammer I. Trender-Gerhard G. Schuierer H. E. Klein 《Der Nervenarzt》2002,24(1):879-882
Wir berichten über den ersten Fall von polyzystischer lipomembran?ser Osteodysplasie oder “brain, bone and fat disease” in
Deutschland. Die nach dem Erstbeschreibern auch als Morbus J?rvi-Hakola-Nasu bezeichnete Erkrankung ist bisher vor allem in
Japan und in Finnland beschrieben worden. Einzelne F?lle wurden aus Schweden, Norwegen, Italien, Südafrika, Belgien und den
USA berichtet. Im deutschsprachigen Raum ist bisher ein Fall aus ? ver?ffentlicht worden. 相似文献
997.
998.
Neurological dysfunction of the bladder in workers exposed to dimethylaminopropionitrile 总被引:1,自引:0,他引:1
Neurogenic bladder dysfunction, characterized by hesitancy, need to strain, decreased stream, and increased duration of urination, developed in 104 (63%) of 166 employees working in the manufacture of polyurethane foam. Highest rates of illness (69%) occurred in production workers, and no illness occurred in office or warehouse workers. Onset of the epidemic coincided with introduction of a catalyst, dimethylaminopropionitrile (DMAPN), and monthly case incidence rates increased as DMAPN use increased. Outbreak ceased abruptly when DMAPN use was stopped. Of eight patients who underwent neurourologic testing during recovery, seven lacked either detrusor reflex or normal sensation of bladder filling; seven had a subclinical sensory abnormality; three had prolonged sacral-evoked responses; and two of these three had limb motor neuropathies. Dimethylaminopropionitrile is unique among known neurotoxins in producing urinary symptoms more frequently than limb nerve symptoms. 相似文献
999.
G E Davies A V Thompson Z Niewola G E Burrows E L Teasdale D J Bird D A Phillips 《Occupational and environmental medicine》1983,40(4):442-449
Twenty four volunteers who had been allergic to laboratory animals for some years were examined by means of a questionnaire paying particular attention to symptoms associated with rats and by serological and skin tests with extracts of rat urine (retrospective study). Nasal and eye symptoms were reported by 21 and 16 individuals respectively: 13 had asthma. Positive skin tests and high levels of specific IgE antibody to rat urine extract were found in 17 of the more severely affected individuals and this group included 12 of those with asthma. Latent periods of work with animals before symptoms appeared varied from 0.5 to 12 years. Also 148 individuals were studied during their first year of work with animals (prospective study). Symptoms developing during the year were reported by 15%, asthma by 2%. IgE antibody levels to rat urine were raised in 40% of affected and 6% of the unaffected individuals but there was no significant correlation between symptoms and either antibody levels or positive skin tests. Allergic symptoms developing during the first year of postemployment were, on the whole, much milder than those seen in the retrospective study. A tentative conclusion is that most individuals who become allergic to laboratory animals develop the condition in a mild form during their first year of employment but it appears probable that atopic individuals, although having an equal chance of developing allergy as compared with non-atopic individuals, may eventually progress to a more severe form of the disease. 相似文献
1000.
In comparative histological and cytological studies on 270 prostatic carcinoma patients highly and moderately differentiated tumors were found to be more frequent histologically than cytologically. An early and reliable sign of response to hormone therapy proved to be reticularization and vacuolization of the nuclear chromatin. Follow-up studies by means of multiple aspiration biopsies with cytologic examinations seem to be more reliable in prognostic terms than examination of the histological tumor structure. 相似文献