全文获取类型
收费全文 | 939篇 |
免费 | 42篇 |
国内免费 | 28篇 |
专业分类
儿科学 | 27篇 |
妇产科学 | 10篇 |
基础医学 | 83篇 |
口腔科学 | 266篇 |
临床医学 | 64篇 |
内科学 | 94篇 |
皮肤病学 | 15篇 |
神经病学 | 6篇 |
特种医学 | 159篇 |
外科学 | 50篇 |
综合类 | 122篇 |
预防医学 | 24篇 |
药学 | 57篇 |
1篇 | |
肿瘤学 | 31篇 |
出版年
2023年 | 5篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 14篇 |
2013年 | 24篇 |
2012年 | 32篇 |
2011年 | 19篇 |
2010年 | 27篇 |
2009年 | 38篇 |
2008年 | 35篇 |
2007年 | 43篇 |
2006年 | 29篇 |
2005年 | 22篇 |
2004年 | 27篇 |
2003年 | 21篇 |
2002年 | 18篇 |
2001年 | 24篇 |
2000年 | 21篇 |
1999年 | 19篇 |
1998年 | 51篇 |
1997年 | 42篇 |
1996年 | 42篇 |
1995年 | 27篇 |
1994年 | 25篇 |
1993年 | 23篇 |
1992年 | 16篇 |
1991年 | 14篇 |
1990年 | 11篇 |
1989年 | 32篇 |
1988年 | 28篇 |
1987年 | 27篇 |
1986年 | 26篇 |
1985年 | 28篇 |
1984年 | 16篇 |
1983年 | 15篇 |
1982年 | 27篇 |
1981年 | 11篇 |
1980年 | 17篇 |
1979年 | 14篇 |
1978年 | 12篇 |
1977年 | 13篇 |
1976年 | 11篇 |
1975年 | 9篇 |
1966年 | 3篇 |
1955年 | 2篇 |
1953年 | 2篇 |
排序方式: 共有1009条查询结果,搜索用时 15 毫秒
1.
S Gunasti† SS Marakli† I Tuncer‡ N Ozpoyraz§ VL Aksungur† 《Journal of the European Academy of Dermatology and Venereology》2007,21(6):811-817
BACKGROUND: We have seen several patients with itchy lichenified plaques located bilaterally on the elbows and/or knees and have named this condition 'psoriatic neurodermatitis' (PN). OBJECTIVE: The purpose of this study was to compare clinical and histopathological characteristics of these patients to those of patients with typical lichen simplex chronicus (LSC). METHODS: Nineteen patients with PN and 34 patients with typical LSC were included. Besides clinical dermatological evaluation, the prick test was carried out on 49 patients; the Phadiatop test on 40 patients; the patch test with European standard series on 47 patients; histopathological evaluation on 39 patients; and clinical psychiatric examination on 38 patients. RESULTS: Almost exclusively, PN was seen in females and was located on the extremities. It caused more plaques than typical LSC did. In PN, the plaques were smaller, sharper, more keratotic and less excoriated, and had fewer lichenoid papules around them. Itching was usually more severe in the evening, while resting and in a hot environment in typical LSC, but not in PN. In plaques of PN, microabscesses in the horny layer, hypogranulosis, regular acanthosis and thinning of the suprapapillary plates were more frequent, and hyperpigmentation in the basal layer was less. In patients with PN, depressive disorder was found more frequently; and generalized anxiety disorder or psychosomatic characteristics, less. There were no significant differences in the results of prick, Phadiatop and patch tests between patients with PN and those with typical LSC. CONCLUSION: In our opinion, it is most likely that the so-called PN is itchy psoriasis superimposed by LSC. 相似文献
2.
3.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
5.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
6.
7.
8.
A "reverse" hybridization method is described, in which whole chromosomal DNA was extracted from 10-20 colonies of "unknown" strains in pure culture and labelled with digoxigenin by a random primer technique. DNA probes were prepared from a total of 23 strains and hybridized with targets containing 100 ng purified, denatured DNA from 38 reference strains fixed to nitrocellulose. 21/23 digoxigenin-labelled DNA probes successfully detected all members of the homologous species present on filters. Probes to Fusobacterium nucleatum strains 364 and MG detected 3/4 and 1/4 members of this species, respectively; 13/23 probes were 100% specific, but cross reactions between 10 probes and DNA targets from closely related, heterologous species occurred in 15/834 possible instances. False-positive reactions that occurred between closely related species were, however, easily distinguished and did not prevent the accurate identification of probe strains. Digoxigenin-labelled probes were capable of detecting 100 pg of homologous DNA. The reverse hybridization procedure allows identification or grouping of a large number of isolates within 3 days and provides a more economical means of characterizing subgingival isolates than predominant cultivable techniques and conventional phenotypic testing. This method could be adapted for the direct identification of microorganisms in subgingival plaque samples. 相似文献
9.
Role of bacterial products in periodontitis: immune response in gnotobiotic rats monoinfected with Eikenella corrodens. 下载免费PDF全文
D A Johnson U H Behling C H Lai M Listgarten S Socransky A Nowotny 《Infection and immunity》1978,19(1):246-253
The development of humoral and cell-mediated immune responses to Eikenella corrodens (a bacterium that causes periodontal lesions in gnotobiotic rats) was measured and compared with the rate of appearance of macroscopic lesions. A possible inverse relationship was found. A strong cell-mediated immune response, as measured by skin reactivity and lymphocyte mitogenesis, occurred between 4 and 6 weeks after infection and subsided soon thereafter to a low response level. Humoral antibodies to endotoxin from E. corrodens could not be detected at any time. The disease developed only after the cell-mediated immune response diminished, thus suggesting that lack of an efficient immune response may permit the development of the disease. This is seemingly in contradiction to the assumption that tissue destruction in such cases is caused by the immune response and its products. We are inclined to believe, based on our findings reported here, that the lack of immune responsiveness to the bacterium and/or its products is the major causative factor in the development of periodontitis. At the same time, we wish to emphasize that occurrence of both phenomena during the long development of periodontal disease is possible. 相似文献
10.