全文获取类型
收费全文 | 1629篇 |
免费 | 67篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 27篇 |
妇产科学 | 16篇 |
基础医学 | 182篇 |
口腔科学 | 346篇 |
临床医学 | 83篇 |
内科学 | 287篇 |
皮肤病学 | 18篇 |
神经病学 | 91篇 |
特种医学 | 57篇 |
外科学 | 158篇 |
综合类 | 6篇 |
预防医学 | 240篇 |
眼科学 | 47篇 |
药学 | 86篇 |
中国医学 | 18篇 |
肿瘤学 | 25篇 |
出版年
2023年 | 14篇 |
2022年 | 16篇 |
2021年 | 58篇 |
2020年 | 39篇 |
2019年 | 40篇 |
2018年 | 46篇 |
2017年 | 38篇 |
2016年 | 31篇 |
2015年 | 38篇 |
2014年 | 56篇 |
2013年 | 86篇 |
2012年 | 101篇 |
2011年 | 132篇 |
2010年 | 83篇 |
2009年 | 58篇 |
2008年 | 90篇 |
2007年 | 102篇 |
2006年 | 91篇 |
2005年 | 73篇 |
2004年 | 64篇 |
2003年 | 58篇 |
2002年 | 57篇 |
2001年 | 28篇 |
2000年 | 29篇 |
1999年 | 18篇 |
1998年 | 20篇 |
1997年 | 17篇 |
1996年 | 11篇 |
1995年 | 9篇 |
1994年 | 7篇 |
1993年 | 13篇 |
1992年 | 7篇 |
1991年 | 8篇 |
1990年 | 8篇 |
1989年 | 12篇 |
1988年 | 12篇 |
1987年 | 11篇 |
1986年 | 6篇 |
1985年 | 20篇 |
1984年 | 6篇 |
1981年 | 5篇 |
1979年 | 8篇 |
1975年 | 9篇 |
1973年 | 8篇 |
1972年 | 4篇 |
1970年 | 4篇 |
1969年 | 5篇 |
1968年 | 6篇 |
1967年 | 8篇 |
1965年 | 4篇 |
排序方式: 共有1699条查询结果,搜索用时 125 毫秒
1.
2.
The authors present a synthesis of the proposals put forth by the health sector of Venezuela during the framing of the new Venezuelan Constitution. They summarize the background to the National Constituent Assembly and the legal framework typical of the health sector at that time, identify the methodological aspects that substantiated the health topics included in the new Constitution, and analyze the articles that shape the current constitutional health framework in Venezuela, summarizing their most important features and comparing them with neoliberal health proposals. 相似文献
3.
4.
5.
6.
Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
7.
Xavier AC Siqueira SA Costa LJ Mauad T Nascimento Saldiva PH 《Virchows Archiv : an international journal of pathology》2005,446(3):225-231
Autopsy findings of missed diagnoses that would probably have changed management or prognosis occur in up to 29% of cases in general hospitals. Such proportions may be higher in subsets of patients with complex diseases. We reviewed 2908 consecutive autopsies performed over a period of 29 months in a large-volume hospital, analyzing 118 autopsies of patients with hematological malignancies or severe aplastic anemia. A review of macroscopic reports as well as microscopic examination of tissue samples was performed. Medical records were reviewed for clinical diagnoses. Discordances between clinical and autopsy diagnoses were classified using Goldmans criteria. Additionally, we searched for clinical parameters correlated with occurrence of class-I discrepancy using a multivariate method. Median age was 46.5 years, and 25.4% had received a hematopoietic stem-cell transplant. Overall, 11.9% (6.6–19.1%) of patients died before conclusion of the hematological diagnosis and 33% (24.6–42.3%) died with no active hematological disease. We found class-I discrepancy in 31.3% (23.1–40.5 %) of cases. The most common among these diagnoses were hematological disease, pneumonia and gastrointestinal bleeding. In a univariate analysis, being elderly (P=0.04) was positively correlated with the finding of class-I discrepancies; while, having received previous specific hematological treatment (P=0.0005) or hematopoietic stem-cell transplants (P=0.013), or being admitted to a specialized hematology unit (P=0.0006) were negatively correlated to the occurrence of such discrepancies. Multivariate analysis showed that care in a specialized hematology unit (OR 0.34, 0.12–0.93) was independently associated with lower occurrence of discrepancies. We concluded that critical diagnoses are often missed in highly complex hematological patients especially in the absence of admission to specialized hematology units. 相似文献
8.
V. L. Calich L. M. Singer-Vermes A. M. Siqueira E. Burger 《International journal of experimental pathology》1985,66(5):585-594
Nine different inbred strains of mice inoculated intraperitoneally with yeast cells of Paracoccidioides brasiliensis showed significantly varying patterns of susceptibility. The A/SN strain was found to be the most resistant, while BIOD2/nSn, BIO.A and BIOD2/oSn the most susceptible strains. These susceptibility differences were not dependent on the size of challenge inocula and sex of animals. All strains studied showed a mean survival time proportional to the size of inocula used. Although almost all infected male mice presented a shorter survival time when compared with females, significant mortality differences between sexes were found only in two of the strains studied, namely BALB/c and BIOD2/nSn. The H-2 region did not influence the susceptibility pattern since the A/SN and BIO.A strains share the same H-2 haplotype and were respectively highly resistant and susceptible to P. brasiliensis. Furthermore, the presence of C5 and unresponsiveness to lipopolysaccharide had no influence on the mortality data observed. Specific antibodies were detected only in a small number of animals and titres were consistently low, appearing later in the resistant (A/SN) than in a susceptible strain (BIO.A). Omentum, spleen and liver were the most affected organs in both strains, but the susceptible mice had more granulomatous lesions and earlier dissemination of the fungus. 相似文献
9.
Haemorrhagic reactions elicited at sites of passive cutaneous anaphylaxis by the intravenous injection of aggregated γ-globulin
下载免费PDF全文
![点击此处可从《Immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
In guinea-pigs injected intradermally with a small amount of antibody and challenged 2 hours later, by the intravenous route, with a mixture of homologous antigen and aggregated γ-globulin, haemorrhagic reactions of the Arthus type develop at the sites of intradermal sensitization. This effect was obtained with γ-globulins of different species (human, rabbit and horse) by using different techniques for aggregation (heat, mercaptoethanol—urea and bis-diazobenzidine) and was always correlated with the ability of the aggregated globulin to fix complement.
Fluorescein labelled aggregates of γ-globulin were detectable in the wall of vessels at sensitized sites.
In experiments performed with guinea-pig antibodies, the localizing effect was observed only with γ1, whereas the γ2, Arthus-producing fraction proved completely ineffective.
Histamine and histamine liberators are not sufficient for eliciting the effect obtained with sensitizing antibody plus homologous antigen. It is postulated, therefore, that other effects occurring at the site of specific sensitization may also be responsible for the phenomenon.
相似文献