全文获取类型
收费全文 | 3952篇 |
免费 | 270篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 64篇 |
儿科学 | 171篇 |
妇产科学 | 89篇 |
基础医学 | 463篇 |
口腔科学 | 157篇 |
临床医学 | 398篇 |
内科学 | 802篇 |
皮肤病学 | 223篇 |
神经病学 | 348篇 |
特种医学 | 159篇 |
外科学 | 435篇 |
综合类 | 33篇 |
一般理论 | 2篇 |
预防医学 | 306篇 |
眼科学 | 18篇 |
药学 | 361篇 |
中国医学 | 4篇 |
肿瘤学 | 195篇 |
出版年
2021年 | 59篇 |
2020年 | 39篇 |
2019年 | 52篇 |
2018年 | 73篇 |
2017年 | 45篇 |
2016年 | 71篇 |
2015年 | 76篇 |
2014年 | 82篇 |
2013年 | 148篇 |
2012年 | 164篇 |
2011年 | 171篇 |
2010年 | 116篇 |
2009年 | 102篇 |
2008年 | 191篇 |
2007年 | 196篇 |
2006年 | 188篇 |
2005年 | 151篇 |
2004年 | 137篇 |
2003年 | 143篇 |
2002年 | 149篇 |
2001年 | 138篇 |
2000年 | 137篇 |
1999年 | 125篇 |
1998年 | 45篇 |
1997年 | 49篇 |
1996年 | 35篇 |
1995年 | 34篇 |
1994年 | 34篇 |
1993年 | 28篇 |
1992年 | 83篇 |
1991年 | 80篇 |
1990年 | 87篇 |
1989年 | 89篇 |
1988年 | 79篇 |
1987年 | 71篇 |
1986年 | 68篇 |
1985年 | 68篇 |
1984年 | 49篇 |
1983年 | 49篇 |
1982年 | 26篇 |
1981年 | 27篇 |
1979年 | 37篇 |
1978年 | 32篇 |
1977年 | 34篇 |
1975年 | 29篇 |
1974年 | 26篇 |
1972年 | 37篇 |
1971年 | 27篇 |
1969年 | 28篇 |
1967年 | 25篇 |
排序方式: 共有4228条查询结果,搜索用时 31 毫秒
41.
Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献42.
Outcome of surgical treatment for early adenocarcinoma of the esophagus or gastro-esophageal junction 总被引:10,自引:0,他引:10
Westerterp M Koppert LB Buskens CJ Tilanus HW ten Kate FJ Bergman JJ Siersema PD van Dekken H van Lanschot JJ 《Virchows Archiv : an international journal of pathology》2005,446(5):497-504
Adenocarcinoma of the esophagus, or GEJ, has a poor prognosis. Early lesions [i.e. high grade dysplasia (HGD) or T1-carcinoma] are potentially curable. Local endoscopic therapies are promising treatment options for superficial lesions; however, for deeper lesions, surgical resection is considered to be the treatment of choice. To contribute to therapeutic decision-making, we retrospectively analysed the outcome of transhiatal esophagectomy in 120 patients with pathologically proven HGD (n=13) or T1-adenocarcinoma (n=107) of the distal esophagus or gastro-esophageal junction (GEJ). Tumors were subdivided into six different depths of invasion (T1-mucosal m1-m3, T1-submucosal sm1-sm3), and the frequency of lymphatic dissemination and time to locoregional and/or distant recurrence were analysed. Only one of the 79 T1m1-3/sm1 tumors (1%) showed lymph node metastases as compared with 18 out of 41 T1sm2-3 tumors (44%). There was a significant difference in recurrence-free period between T1m1-m3/sm1 versus T1sm2-sm3 tumor patients (P log rank <0.0001), with 5-year recurrence-free percentages of 97% and 57%, respectively. In multivariate analysis including age, gender, tumor differentiation grade, N-stage and depth of invasion, only N-stage was an independent prognostic factor for recurrence-free period (hazard rate=5.9, 95% CI 1.7–20.7). However, if N-stage was excluded from analysis, only depth of invasion (T1sm2-3 versus T1m1-m3/sm1) was an independent prognostic factor for recurrence-free period (hazard rate=7.5, 95% CI 2.0–27.7). These data indicate that T1m1-m3/sm1 adenocarcinomas of esophagus or GEJ show a very low risk of lymphatic dissemination and are therefore eligible for local endoscopic therapy. After transhiatal surgical resection, almost half of the patients with T1sm2-sm3 lesions develop recurrent disease within 5 years, and therefore need additional therapy to improve survival. 相似文献
43.
George J Barshack I Keren P Gazit A Levitzki A Keren G Roth A 《Experimental and molecular pathology》2005,78(3):233-238
BACKGROUND: Inflammation has been shown to play an important role in promoting the response to arterial injury and proinflammatory cytokines, such as tumor necrosis factor (TNF) alpha, are candidate mediators. AG-556 is a tyrosine kinase inhibitor proven to be effective in a model of multiple sclerosis-like syndrome in mice due to its immunomodulating effect. In the current study, we investigated the effect of the tyrphostin AG-556 on neointimal thickening and cytokine profile in a model of arterial injury in the mouse. METHODS: Injury was induced by external cuff placement on the left femoral artery of wild-type C57BL/6 mice. AG-556 dissolved in DMSO was injected intraperitoneally daily to the injured mice in a dosage of 2 mg/mouse. Control mice received DMSO injections. Histological analysis was carried out to assess neointimal formation. Splenocytes were cultured in the absence and presence of a mitogen for evaluation of thymidine incorporation and cytokine production. RESULTS: AG-556 treatment significantly attenuated intimal thickening (43,000+/-17,000 microm2; n=11) when compared to DMSO administration (286,000+/-127,000 microm2; n=10; P<0.05). Basal interferon-gamma production by splenocytes from AG-556-treated mice was increased by approximately 20-fold in comparison with levels in DMSO-treated animals, whereas Con-A induced secretion of the cytokine was similar between both groups. Levels of TNF-alpha, IL-4 and IL-10 in the culture supernatant from treated and non-treated animals did not differ significantly. CONCLUSION: The tyrosine kinase inhibitor AG-556 may have a role in the reduction of intimal thickening. The effect could be mediated via an immune modulating effect involving a significant increase in the smooth muscle cell inhibitory cytokine IFN-gamma. 相似文献
44.
L. F. Fitzgerald, C. L. Hulin, and F. Drasgow (1995) proposed that victim characteristics, such as race, might moderate the relationships between sexual harassment and its job, psychological, and health status outcomes. This study describes 2 theoretical positions, tokenism and double jeopardy, that could account for this possible moderation by race, as well as the alternative view that no moderating effects exist. The effects of race are empirically examined through simultaneous path analysis. Results indicate that whereas mean levels of harassment differ across race, the phenomenon of sexual harassment unfolds similarly across races; race is not a moderator of the relationships between sexual harassment and the variables proposed as its antecedents and outcomes. 相似文献
45.
S Schwarzbaum A Nissim I Alkalay M C Ghozi D G Schindler Y Bergman Z Eshhar 《European journal of immunology》1989,19(6):1015-1023
The generation of anti-IgE monoclonal antibodies has permitted the identification of various serological epitopes on the IgE molecule. The relationship of the sites on IgE recognized by such antibodies to the Fc epsilon receptor (Fc epsilon R) interaction site has been determined using cross-inhibition studies. However, interpretation of this type of experiment is limited by problems of steric hindrance. Thus, to accomplish precise mapping on the IgE molecule of the Fc epsilon R interaction site and the binding sites of various anti-IgE mAb, we employed site-directed mutagenesis of the IgE heavy chain gene. To this end we have constructed and expressed a recombinant murine constant epsilon heavy chain (C epsilon) gene bearing a (4-hydroxy-3-nitrophenyl)acetic acid (NP)-binding VH region. Several site-specific mutants in the C epsilon 3 and C epsilon 4 domains of this recombinant C epsilon gene were prepared and expressed by transfection into the light chain-producing J558L myeloma cell line. The resulting IgE antibodies were tested for binding to mast cells and to various anti-IgE mAb. The mutants produced include a proline to histidine point mutant at amino acid residue 404 in the C epsilon 3 domain, a mutant with a truncated C epsilon 4 domain, a mutant with a 45 amino acid deletion in the carboxy end of C epsilon 3, and a chimeric human C epsilon in which the human C epsilon 3 was replaced by the homologous mouse C epsilon 3 domain. These mutants have permitted the localization, to the C epsilon 3 domain, of the epitopes recognized by the 84.1C and 95.3 anti-IgE mAb. The 84.1C mAb recognizes a site on IgE which is identical or very close to the Fc epsilon R binding site, and 95.3 recognizes a site on IgE which is related, but not identical to the Fc epsilon R binding site. The antigenic determinant recognized by the 51.3 mAb, which is inefficient at blocking the IgE-Fc epsilon R interaction, has been mapped to the C epsilon 4 domain. When tested for binding to the Fc epsilon R on RBL-2H3 cells, the point mutant bound to the Fc epsilon R with twofold reduced affinity, while the C epsilon 3 deletion mutant and the mutant truncated in C epsilon 4 lost all receptor binding activity.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
46.
C. W. Ang K. Krogfelt P. Herbrink J. Keijser W. van Pelt T. Dalby M. Kuijf B. C. Jacobs M. P. Bergman P. Schiellerup C. E. Visser 《Clinical microbiology and infection》2007,13(9):915-922
Weeks or months following Campylobacter infection, a small proportion of infected individuals develop Guillain-Barré syndrome (GBS) or reactive arthritis (ReA). Stool culture for Campylobacter is often negative in these patients, and serology is therefore the method of choice for diagnosing a recent infection with Campylobacter. This study developed a capture ELISA system to detect anti-Campylobacter IgA and IgM antibodies indicative of a recent infection. The sensitivity of the assay was 82.0% in uncomplicated Campylobacter enteritis patients, 96.2% in GBS patients who were culture-positive for Campylobacter, and 93.1% in culture-positive ReA patients, with a specificity of 93.0%. The assay allows identification of Campylobacter infection in patients with post-infectious neurological and rheumatological complications. 相似文献
47.
Fordyce Wilbert E. Brockway Jo Ann Bergman James A. Spengler Daniel 《Journal of behavioral medicine》1986,9(2):127-140
Back-pain patients with onset in the preceding 1–10 days and comparable on a back examination were randomly assigned to traditional management (A regimen) and behavioral treatment methods (B regimen). Patients were compared at 6 weeks and 9–12 months on a set of Sick/Well scores derived from patient reported vocational status (V), health-care utilization (HCU), claimed impairment (CI), and pain drawings (D) and on two measures of activity level. No differences were found at 6 weeks, but at 9–12 months, A-group S's were more sick. No A/B differences were found on activity-level measures. Group A S's showed significant increases in claimed impairment from preonset to follow-up, whereas Group B S's had returned at follow-up to preonset levelsA special acknowledgment is made to Darnel Rock, M.S., now of the Department of Psychology, Vanderbilt University, for his major contributions to the organization and analysis of the data of this study. 相似文献
48.
Vujic M Bergman A Romanus B Wahlström J Martinsson T 《International journal of molecular medicine》2004,13(1):47-52
Hereditary multiple exostoses (HME) is a well known autosomal dominant hereditary orthopedic disorder. Isolated exostoses, on the other hand, occur as sporadic events or as secondary post-traumatic sequel. The occurrence of solitary exostoses in individuals from pedigrees affected with HME may distort conclusions about carrier status and/or diagnosis. Both conditions are potentially malignant and both are associated with genetic alterations in either EXT1 or EXT2 genes. In this study, we present a seven-generation family from western Sweden consisting of 170 blood relatives, 38 of whom had multiple cartilaginous exostoses, while 8 had isolated exostoses. Linkage analysis aimed to discern one of the known EXT genes demonstrated linkage of the HME phenotype to the EXT2 gene. Subsequent mutation analysis revealed a novel mutation, nt112delAT, in this gene. All carriers of the detected mutation had multiple exostoses, indicating full penetrance. None of the pedigree members with isolated exostoses were carriers of the detected mutation. Two of the mutation carriers developed chondrosarcoma yielding a 5.2% risk of malignant development for this mutation. The detection of this mutation has enabled us to provide appropriate genetic counseling concerning this complex situation. 相似文献
49.
A lymphocytic tumor, 38C-13, induced by the chemical carcinogen 7, 12-dimethylbenz(a)anthracene in C3H/eB mice and adapted to tissue culture, produces 7-8 S IgM with "core" carbohydrates (N-acetylglucosamines, mannoses), but not "branch" carbohydrates (neuraminic acids, fucoses, galactoses) attached to the mu heavy, but not to the light chains. Turnover of the 7-8 S 38C-13 IgM is slow (half disappearance time = 10-15 h). The IgM is released from the cells as 7-8 S IgM. The ratio of IgM synthesis to the synthesis of all cellular glycoproteins is 0.005-0.01. After comparison of these data with data obtained with normal B lymphocytes before and after mitogenic stimulation, we conclude that 38C-13 tumor cells are transformed counterparts very near or within the population of small, mitogen-sensitive, resting B lymphocytes. 相似文献
50.