全文获取类型
收费全文 | 580篇 |
免费 | 115篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 19篇 |
妇产科学 | 5篇 |
基础医学 | 118篇 |
口腔科学 | 3篇 |
临床医学 | 85篇 |
内科学 | 79篇 |
皮肤病学 | 13篇 |
神经病学 | 11篇 |
特种医学 | 123篇 |
外科学 | 26篇 |
综合类 | 36篇 |
预防医学 | 29篇 |
眼科学 | 1篇 |
药学 | 14篇 |
中国医学 | 2篇 |
肿瘤学 | 137篇 |
出版年
2024年 | 2篇 |
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 12篇 |
2020年 | 8篇 |
2019年 | 10篇 |
2018年 | 26篇 |
2017年 | 17篇 |
2016年 | 23篇 |
2015年 | 14篇 |
2014年 | 25篇 |
2013年 | 30篇 |
2012年 | 19篇 |
2011年 | 23篇 |
2010年 | 21篇 |
2009年 | 29篇 |
2008年 | 19篇 |
2007年 | 26篇 |
2006年 | 13篇 |
2005年 | 14篇 |
2004年 | 32篇 |
2003年 | 33篇 |
2002年 | 34篇 |
2001年 | 35篇 |
2000年 | 18篇 |
1999年 | 21篇 |
1998年 | 34篇 |
1997年 | 15篇 |
1996年 | 14篇 |
1995年 | 12篇 |
1994年 | 15篇 |
1993年 | 18篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1974年 | 1篇 |
排序方式: 共有702条查询结果,搜索用时 546 毫秒
41.
原发性颅内恶性淋巴瘤的CT诊断郭凡樊长姝北京铁路总医院CT室100038提要对6例经手术病理证实的原发性颅内恶性淋巴瘤的CT表现进行分析后,认为对发生在中线区表现为均匀高密度,边缘清楚具有分叶征象的病灶,可作为CT的表现的特点。在放、化疗过程中出现肿... 相似文献
42.
Westendorp IC Tiemessen MA de Jong M Soomers A Wakelkamp IM Boersma WG 《The Netherlands journal of medicine》2005,63(6):227-229
Moraxella catarrhalis rarely causes severe infections or bacteraemia in healthy subjects. In the literature only four cases of clinical sepsis with M. catarrhalis have been described, mostly in immunocompromised patients. We describe a case of a 34-year-old patient with Kugelberg-Welander disease and low body weight (28 kg) who developed clinical sepsis due to M. catarrhalis bacteraemia. A review of the literature is given. 相似文献
43.
Sherman GG Scott LE Galpin JS Kuhn L Tiemessen CT Simmank K Meddows-Taylor S Meyers TM 《Pediatric research》2002,51(6):740-745
Increased expression of CD38 on CD8(+) T cells is associated with activation of the immune system, progression of HIV disease, and death in adults. The prognostic significance of these cells in HIV-infected children, where the picture is complicated by age-related differences in CD38 expression, remains controversial. Measuring the unimodal expression of CD38 on CD8(+) T cells in adults and children by flow cytometry is best accomplished by quantitating the antigen on the cell surface. To our knowledge, this technique has not previously been reported in a pediatric population. Vertically HIV-infected children were age matched for mild (n = 26) and severe (n = 23) clinical disease. Eleven age-matched HIV-negative controls were included for comparison. Quantitation of CD38 on CD8(+) T cells was performed at baseline and 1 y later. The ages of the children in the three clinical groups did not differ significantly (p = 0.6004). HIV-infected children had significantly increased CD38 measurements in comparison with the HIV-negative controls (p = 0.0131), and the severe disease group tended to have higher measurements than the mild disease group. Increased CD38(+)CD8(+) T cells were significant predictors of death within the first year (p = 0.043). These findings support the view that increased CD38 expression on CD8(+) T cells has the same prognostic significance in pediatric as in adult HIV disease. 相似文献
44.
45.
Pronk M Tiemessen I Hupperets MD Kennedy BP Powell FL Hopkins SR Wagner PD 《High altitude medicine & biology》2003,4(4):431-443
The arterial blood lactate [La] response to exercise increases in acute hypoxia, but returns to near the normoxic (sea level, SL) response after 2 to 5 weeks of altitude acclimatization. Recently, it has been suggested that this gradual return to the SL response in [La], known as the lactate paradox (LP), unexpectedly disappears after 8 to 9 weeks at altitude. We tested this idea by recording the [La] response to exercise every 2 weeks over 8 weeks at altitude. Five normal, fit SL-residents were studied at SL and 3,800 m (Pbar = 485 torr) in both normoxia (PIO2 = 150 torr) and hypoxia (PIO2 = 91 torr approximately air at 3,800 m). Arterial [La] and blood gas values were determined at rest and during cycle exercise at the same absolute workloads (0, 25, 50, 75, 90, and 100% of initial SL-VO2Max) and exercise duration (4, 4, 4, 2, 1.5, and 0.75 min, respectively) at each time point. [La] curves were elevated in acute hypoxia at SL (p < 0.01) and at 3,800 m fell progressively toward the SL-normoxic curve (p < 0.01). On the same days, [La] responses in acute normoxia showed essentially no changes over time and were similar to initial SL normoxic responses. We also measured arterial catecholamine levels at each load and found a close relationship to [La] over time, supporting a role for adrenergic influence on [La]. In summary, extending the time at this altitude to 8 weeks produced no evidence for reversal of the LP, consistent with prior data obtained over shorter periods of altitude residence. 相似文献
46.
47.
Duration of Sample Storage Dramatically Alters Expression of the Human Immunodeficiency Virus Coreceptors CXCR4 and CCR5
下载免费PDF全文
![点击此处可从《Clinical and Vaccine Immunology : CVI》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Expression of the chemokine receptors CXCR4 and CCR5 was monitored using EDTA-anticoagulated whole blood held for different time periods prior to fluorescent-antibody staining. When left overnight CXCR4 expression on leukocytes was substantially increased, whereas CCR5 expression was reduced. The results were similar when heparin and acid-citrate-dextrose were used as anticoagulants. 相似文献
48.
49.
BACKGROUND:
The FocalPoint Slide Profiler is an automated cervical cytology screening system that is approved for primary screening. It identifies up to 25% of slides as requiring No Further Review. However, few studies have evaluated FocalPoint performance with glandular abnormalities.METHODS:
Sixty‐six SurePath Papanicolaou (Pap) tests with a diagnosis of atypical glandular cells were identified. A total of 172 Pap tests with a diagnosis of “endometrial cells present” were included as controls. Follow‐up histology was abnormal if diagnosed as high‐grade squamous intraepithelial lesions, adenocarcinoma in situ, carcinoma, or complex endometrial hyperplasia. The FocalPoint software ranked each case into 1 of 7 categories: quintiles 1 (high risk) through 5 (low risk), No Further Review, and Process Review.RESULTS:
A total of 215 slides were qualified for review; 38 (57.6%) atypical glandular cells cases were abnormal on follow‐up biopsy, and 27 (71.1%) atypical glandular cells with abnormal follow‐up qualified for review; no cases were classified No Further Review, and 9 (33%) were ranked in quintile 1. Twenty‐three (82.1%) atypical glandular cells with benign follow‐up were qualified for review; 3 (11%) cases were classified No Further Review, and 4 (17%) were ranked in quintile 1. There was a statistically significant difference between the ranking of benign atypical glandular cells cases, abnormal atypical glandular cells cases, and control cases (P = .03). However, when collapsed into No Further Review versus all other quintiles, the differences were not significant (P = .20).CONCLUSIONS:
The FocalPoint Slide Profiler did not classify glandular lesions with abnormal follow‐up in the No Further Review category. However, these cases were not preferentially ranked in quintile 1. FocalPoint‐screened slides need to be carefully reviewed for glandular abnormalities, regardless of the quintile ranking. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society. 相似文献50.
Modern surgical teaching is evolving at speed. The environment in which we learn and teach is subject to a number of extrinsic pressures. These are influencing ways in which medical students and trainees learn and are taught the discipline of surgery. As a surgical educator it is useful to understand the reasons for these changes and to acquire the skills necessary to provide effective teaching. This short article looks at reasons why one would wish to develop surgical teaching skills, covers basic principles associated with delivery of effective teaching sessions and briefly reviews other avenues that may enhance teaching practice. 相似文献