全文获取类型
收费全文 | 537篇 |
免费 | 53篇 |
国内免费 | 45篇 |
专业分类
儿科学 | 39篇 |
妇产科学 | 2篇 |
基础医学 | 71篇 |
口腔科学 | 13篇 |
临床医学 | 89篇 |
内科学 | 128篇 |
皮肤病学 | 8篇 |
神经病学 | 23篇 |
特种医学 | 129篇 |
外科学 | 25篇 |
综合类 | 17篇 |
预防医学 | 19篇 |
眼科学 | 6篇 |
药学 | 50篇 |
中国医学 | 1篇 |
肿瘤学 | 15篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 4篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 4篇 |
2014年 | 9篇 |
2013年 | 13篇 |
2012年 | 4篇 |
2011年 | 5篇 |
2010年 | 24篇 |
2009年 | 23篇 |
2008年 | 8篇 |
2007年 | 35篇 |
2006年 | 7篇 |
2005年 | 10篇 |
2004年 | 7篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 10篇 |
2000年 | 14篇 |
1999年 | 13篇 |
1998年 | 44篇 |
1997年 | 35篇 |
1996年 | 37篇 |
1995年 | 24篇 |
1994年 | 20篇 |
1993年 | 22篇 |
1992年 | 15篇 |
1991年 | 10篇 |
1990年 | 15篇 |
1989年 | 31篇 |
1988年 | 33篇 |
1987年 | 25篇 |
1986年 | 21篇 |
1985年 | 16篇 |
1984年 | 10篇 |
1983年 | 11篇 |
1982年 | 10篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 11篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1974年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有635条查询结果,搜索用时 208 毫秒
1.
2.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
3.
4.
Enhanced mucosal priming by cholera toxin and procholeragenoid with a lipoidal amine adjuvant (avridine) delivered in liposomes
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The mucosal adjuvant activity of avridine, a synthetic lipoidal amine [N,N-dioctadecyl-N',N'-(2-hydroxymethyl) propanediamine, previously designated CP-20,961), was studied in rats immunized intraintestinally with cholera toxin or procholeragenoid. Avridine was most efficient as an adjuvant when incorporated into liposomes; liposomes that lacked avridine had no adjuvant effect. Coadministration of avridine-containing liposomes with enteric priming doses of cholera toxin or procholeragenoid enhanced the efficiency of priming for secondary mucosal anti-cholera toxin responses, i.e., the establishment of memory, five- to sevenfold. Avridine-containing liposomes had no significant effect, however, on either the primary mucosal anti-cholera toxin response, when given with the primary dose of antigen, or on the secondary response, when given with the booster dose to previously primed animals. Little or no adjuvant effect occurred when avridine-containing liposomes were given concurrently with antigen, but at a separate mucosal site or parenterally, or at the site of enteric immunization, but 1 day earlier or later. These results support the notion that adjuvants may be developed which enhance the mucosal immunogenicity of locally applied antigens and suggest that liposomes may be effective vehicles for delivery of such adjuvants. 相似文献
5.
Flow cytometric analysis of the effects exerted by monoclonal antibodies on binding and uptake of Leishmania mexicana subsp. mexicana promastigotes by murine peritoneal macrophages.
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A flow cytometric assay was developed to quantitate the binding kinetics of Leishmania mexicana subsp. mexicana promastigotes to murine peritoneal macrophages and to determine if selected membrane-specific monoclonal antibodies would exert an effect on the binding process. A total of three monoclonal antibodies, all reactive with a similar 42-kilodalton surface membrane component by Western blot analysis, enhanced parasite-macrophage binding at levels greater than 45%. An additional three monoclonal antibodies that identified low-molecular-weight antigens of the promastigote (15 to 20 kilodaltons) had no effect on the binding process. Of these antibodies, however, one did appear to inhibit the internalization of the parasites after it attached to the macrophage membrane. 相似文献
6.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献
7.
Typhus and typhuslike rickettsiae associated with opossums and their fleas in Los Angeles County, California.
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)
S G Williams J B Sacci Jr M E Schriefer E M Andersen K K Fujioka F J Sorvillo A R Barr A F Azad 《Journal of clinical microbiology》1992,30(7):1758-1762
The recent discovery of cat fleas (Ctenocephalides felis) infected with a typhuslike rickettsia (designated the ELB agent) raises the question of whether similar rickettsial infections exist in wild cat flea populations. We verified the presence of the ELB agent and Rickettsia typhi in urban and suburban areas of Los Angeles, Calif. Opossums trapped in close proximity to the residences of human murine typhus cases in Los Angeles county and other areas within the city of Los Angeles were tested for the presence of typhus group rickettsiae by the polymerase chain reaction (PCR). The presence of rickettsiae in the spleen tissues of three opossums (n = 9) and in 66 opossum fleas (n = 205) was determined by PCR and was verified by dot blot and Southern transfer hybridization. Further analysis of the amplified PCR products generated by a series of primer pairs derived from either the 17-kDa antigen gene or the citrate synthase gene revealed that both R. typhi and the ELB agent were present in the tested samples. Dual infection was not noted in the samples; however, the fleas were infected with either R. typhi or the ELB agent. The presence of the ELB agent in the cat flea population may have implications for public health. Whether this agent is responsible for the mild cases of human murine typhus in urban and suburban areas of Los Angeles or in other endemic foci remains to be determined. 相似文献
8.
9.
Based on the dissection of 30 hemi-mandibles, the authors report a study of the inferior alveolar artery in its intraosseous course. On morphologic considerations they propose a classification of the collaterals into two groups: the principal collaterals destined for the teeth and the bony alveolar tissue and the secondary collaterals destined for the sheath and the nerve as well as the bony tissue around the canal. Loss of the teeth and absorption of the alveolar bone modify the caliber of the inferior alveolar arterial axis, the distribution of its collaterals and possibly its mode of termination. These facts suggest a consideration of the vascularization of the mandible in terms of four sectors. They arrive at practical conclusions that may be drawn from this study in stomatology. 相似文献
10.