全文获取类型
收费全文 | 399篇 |
免费 | 22篇 |
国内免费 | 6篇 |
专业分类
儿科学 | 27篇 |
妇产科学 | 3篇 |
基础医学 | 43篇 |
口腔科学 | 9篇 |
临床医学 | 28篇 |
内科学 | 95篇 |
皮肤病学 | 5篇 |
神经病学 | 10篇 |
特种医学 | 85篇 |
外科学 | 33篇 |
综合类 | 7篇 |
预防医学 | 24篇 |
眼科学 | 6篇 |
药学 | 35篇 |
肿瘤学 | 17篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 8篇 |
2014年 | 5篇 |
2013年 | 16篇 |
2012年 | 5篇 |
2011年 | 3篇 |
2010年 | 15篇 |
2009年 | 15篇 |
2008年 | 10篇 |
2007年 | 12篇 |
2006年 | 12篇 |
2005年 | 10篇 |
2004年 | 4篇 |
2003年 | 4篇 |
2002年 | 9篇 |
2001年 | 5篇 |
1999年 | 11篇 |
1998年 | 26篇 |
1997年 | 28篇 |
1996年 | 30篇 |
1995年 | 22篇 |
1994年 | 25篇 |
1993年 | 18篇 |
1992年 | 9篇 |
1991年 | 3篇 |
1990年 | 7篇 |
1989年 | 11篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 10篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 10篇 |
1975年 | 3篇 |
1973年 | 1篇 |
排序方式: 共有427条查询结果,搜索用时 31 毫秒
91.
Independent prognostic significance of a nuclear proliferation antigen in diffuse large cell lymphomas as determined by the monoclonal antibody Ki-67 总被引:12,自引:0,他引:12
Grogan TM; Lippman SM; Spier CM; Slymen DJ; Rybski JA; Rangel CS; Richter LC; Miller TP 《Blood》1988,71(4):1157-1160
To assess the prognostic significance of the growth fraction in diffuse large cell lymphoma (DLCL), we studied 105 DLCL patients with the monoclonal antibody Ki-67 applied to frozen tissue sections. Ki-67 detects a nuclear antigen associated with cell proliferation not found in resting cells. Ki-67 findings and other clinical prognostic factors were correlated with outcome using univariate and multivariate analyses in the proportional hazards model. High proliferative activity, defined as nuclear Ki-67 expression in greater than 60% of malignant cells (Ki- 67 greater than 60), was found to be a strong predictor of poor survival among these patients (P = .003, log-rank). The 19 patients with Ki-67 greater than 60% had a median survival of 8 months compared with a median survival of 39 months for the 86 patients with Ki-67 less than or equal to 60%. Examination of pretreatment clinical variables indicated the patient groups were similar with regard to age, sex, stage, B symptoms, tumor bulk, and lactate dehydrogenase (LDH). Both patient groups received comparable curative intent therapy and showed comparable complete response rate precluding treatment differences as modifying outcome. Multivariate analysis indicated Ki-67 is an independent predictor of survival (multivariate P = .006). Further statistical analysis using only B-cell DLCL patients treated with CHOP (63 patients) indicated that Ki-67 greater than 60 retained strong prediction of poor outcome (P = .002, log-rank) among this homogeneous group. We conclude that high proliferative activity (Ki-67 greater than 60) is an independent factor allowing laboratory prediction of probable poor outcome of DLCL. 相似文献
92.
Between January and March 1986, 117 wives of insulation workers exposed to asbestos were screened by means of chest radiography, pulmonary function testing, and a detailed questionnaire. The final study group included 93 women over 40 years of age. Eighteen of these (19.4%) demonstrated pleural changes consistent with asbestos exposure, including pleural plaque (88.9%), diaphragm plaque (27.8%), pleural calcification (16.6%), and diffuse pleural thickening (5.5%). In statistical correlation between the groups with normal and abnormal radiographs, the only factor that proved significant was the year of first exposure (the duration of the latent period). Finally, radiographs of the husbands were compared for 17 of the 18 wives with radiographic abnormalities. Fourteen of the husbands (82%) demonstrated more severe radiographic changes than their wives. 相似文献
93.
94.
Krimer LS; Hyde TM; Herman MM; Saunders RC 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):722-731
The entorhinal cortex (ERC) has been implicated in the pathophysiology of
Alzheimer's disease, schizophrenia and other disorders affecting cognitive
functions. While powerful anatomical and histochemical methods
(immunohistochemistry, in situ hybridization, etc.) may be applied
(although with limitations) to postmortem human brain, each analysis should
utilize a cytoarchitectonic approach to provide appropriate comparisons
within the subdivisions of the ERC. Accordingly, we describe here the
normal cyto- and myeloarchitecture of the human ERC as a prerequisite for
the accompanying study of this region in schizophrenia. Our parcellation of
this cortex differs from previous treatments in three ways. First, we
adopted specific criteria of inclusion to define each subdivision of the
region. Although distinctive ERC features are most prominent in the
intermediate portion of this region, at least one of these features was
considered the minimum necessary criterion to include adjacent tissue in
the entorhinal area. Second, we used morphometric measurements (neuronal
size and density as well as subdivisional volume and laminar thickness) to
support our qualitative evaluation. Third, we have applied to the human ERC
the conventional cytoarchitectonic nomenclature of the entorhinal cortex
used previously in studies of non-human primates. This allows a more
accurate extrapolation of the available numerous experimental anatomical,
physiological and psychological data on this region to the human. As in the
monkey, the five main subareas were recognized in the human (prorhinal,
lateral, intermediate, sulcal and medial) but three required further
subdivision (intermediate, sulcal and medial). The morphometric results
obtained suggested a progression of the human entorhinal cortex from the
peripheral to the central subareas, with the intermediate subarea (281) as
the most complete entorhinal subdivision. Compared with non-human primates,
the human ERC not only retains the basic periallocortical organization but
also demonstrates further evolution. Taken together with available
experimental data on the connectivity of this brain region, these results
provide an anatomical basis for evaluating the ERC in human behavior.
相似文献
95.
96.
Inhibition of the intrinsic factor X activating complex by protein S: evidence for a specific binding of protein S to factor VIII 总被引:4,自引:2,他引:2
Protein S is a vitamin K-dependent nonenzymatic anticoagulant protein that acts as a cofactor to activated protein C. Recently it was shown that protein S inhibits the prothrombinase reaction independent of activated protein C. In this study, we show that protein S can also inhibit the intrinsic factor X activation via a specific interaction with factor VIII. In the presence of endothelial cells, the intrinsic activation of factor X was inhibited by protein S with an IC50 value of 0.28 +/- 0.04 mumol/L corresponding to the plasma concentration of protein S. This inhibitory effect was even more pronounced when the intrinsic factor X activation was studied in the presence of activated platelets (IC50 = 0.15 +/- 0.02 mumol/L). When a nonlimiting concentration of phospholipid vesicles was used, the plasma concentration of protein S (300 nmol/L) inhibited the intrinsic factor X activation by 40%. Thrombin-cleaved protein S inhibited the endothelial cell-mediated factor X activation with an IC50 similar to that of native protein S (0.26 +/- 0.02 mumol/L). Protein S in complex with C4b-binding protein inhibited the endothelial cell-mediated factor X activation more potently than protein S alone (IC50 = 0.19 +/- 0.03 mumol/L). Using thrombin activated factor VIII, IC50 values of 0.53 +/- 0.09 mumol/L and 0.46 +/- 0.10 mumol/L were found for native protein S and thrombin-cleaved protein S, respectively. The possible interactions of protein S with factor IXa, phospholipids, and factor VIII were investigated. The enzymatic activity of factor IXa was not affected by protein S, and interaction of protein S with the phospholipid surface could not fully explain the inhibitory effect of protein S on the factor X activation. Using a solid-phase binding assay, we showed a specific, saturable, and reversible binding of protein S to factor VIII with a high affinity. The concentration of protein S where half-maximal binding was reached (B1/2max) was 0.41 +/- 0.06 mumol/L. A similar affinity was found for the interaction of thrombin-cleaved protein S with factor VIII (B1/2max = 0.40 +/- 0.04 mumol/L). The affinity of the complex protein S with C4B-binding protein appeared to be five times higher (B1/2max = 0.07 +/- 0.03 mumol/L). Because the affinities of the interaction of the different forms of protein S with factor VIII correspond to the IC50 values observed for the intrinsic factor X activating complex, the interaction of protein S with factor VIII may explain the inhibitory effect of protein S on the intrinsic factor X activating complex.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
97.
98.
99.
100.
RA Schwartz†‡ TM Bridges§ AK Butani† A Ehrlich§ 《Journal of the European Academy of Dermatology and Venereology》2008,22(5):606-615
Solar ultraviolet light electromagnetic waves are a known environmental carcinogenic agent closely associated with the development of skin cancer in light‐complexioned individuals. Outdoor workers have higher annual exposure to ultraviolet light. We will review the topic of actinic keratoses among these individuals as this common rudimentary form of superficial cutaneous squamous cell carcinoma is explored in greater detail. 相似文献