全文获取类型
收费全文 | 349篇 |
免费 | 19篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 30篇 |
妇产科学 | 5篇 |
基础医学 | 29篇 |
口腔科学 | 7篇 |
临床医学 | 35篇 |
内科学 | 79篇 |
皮肤病学 | 14篇 |
神经病学 | 17篇 |
特种医学 | 58篇 |
外科学 | 22篇 |
综合类 | 17篇 |
预防医学 | 37篇 |
眼科学 | 4篇 |
药学 | 18篇 |
肿瘤学 | 13篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 6篇 |
2014年 | 7篇 |
2013年 | 15篇 |
2012年 | 6篇 |
2011年 | 12篇 |
2010年 | 10篇 |
2009年 | 17篇 |
2008年 | 8篇 |
2007年 | 22篇 |
2006年 | 5篇 |
2005年 | 7篇 |
2004年 | 7篇 |
2003年 | 7篇 |
2002年 | 9篇 |
2001年 | 12篇 |
2000年 | 5篇 |
1999年 | 6篇 |
1998年 | 12篇 |
1997年 | 15篇 |
1996年 | 19篇 |
1995年 | 9篇 |
1994年 | 18篇 |
1993年 | 14篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 13篇 |
1988年 | 6篇 |
1987年 | 11篇 |
1986年 | 15篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 6篇 |
1975年 | 3篇 |
1973年 | 1篇 |
排序方式: 共有386条查询结果,搜索用时 15 毫秒
1.
2.
3.
M A Green M A Heumann H M Wehr L R Foster L P Williams Jr J A Polder C L Morgan S L Wagner L A Wanke J M Witt 《American journal of public health》1987,77(11):1431-1434
The largest reported United States outbreak of illness caused by a foodborne pesticide was due to aldicarb-contaminated watermelons. In Oregon, where the first episodes of toxicity were reported, 264 reports were received, and 61 definite cases were identified. Residues of aldicarb, a cholinesterase inhibitor, were found in 10 of 16 tested melons which had been eaten by persons meeting the case definition. The outbreak demonstrates the need for enhanced physician vigilance with respect to anticholinesterase intoxication. It also demonstrates the value of an established system for reporting of unusual illness to public health officials. 相似文献
4.
Promoting clinically effective practice: general practitioners' awareness of sources of research evidence 总被引:3,自引:1,他引:2
Prescott K; Lloyd M; Douglas HR; Haines A; Humphrey C; Rosenthal J; Watt I 《Family practice》1997,14(4):320-323
BACKGROUND: Practitioners are being encouraged to base their clinical
practice on research evidence. In order to do this, they must be aware of
and use the sources of evidence. METHODS: A questionnaire survey was
undertaken to establish GPs' awareness of research evidence in their
clinical practice and, in fundholding practices, its influence on
purchasing plans. Questionnaires were sent to 360 lead fundholders in North
Thames Region and 440 of a random sample of the remaining general
practitioners in the region for comparison. RESULTS: Questionnaires were
returned by 62% of lead fundholders and 63% of GPs in the random sample.
There was limited use of the electronic sources of clinical effectiveness.
There was greater reported awareness of published sources of research
evidence and fundholding GPs were significantly more likely to have
referred to publications summarizing research evidence. CONCLUSIONS: GPs
seem to make more use of published clinical effectiveness sources than the
electronic databases. Consequently, they need educational and technical
support if they are to make full use of the available sources of research
evidence available in other media.
相似文献
5.
6.
Liver-infiltrating T helper cells in autoimmune chronic active hepatitis stimulate the production of autoantibodies against the human asialoglycoprotein receptor in vitro. 总被引:2,自引:0,他引:2 下载免费PDF全文
H. L
HR U. TREICHEL T. PORALLA M. MANNS K. H. MEYER ZUM BÜSCHENFELDE B. FLEISCHER 《Clinical and experimental immunology》1992,88(1):45-49
Autoantibodies against the human asialoglycoprotein receptor (ASGPR) occur in the sera of patients with autoimmune liver disorders. Liver-infiltrating T cell clones that specifically recognize the ASGPR have been described in patients with autoimmune chronic active hepatitis (AI-CAH) and primary biliary cirrhosis (PBC). Recently, we have shown that peripheral blood mononuclear cells (PBMC) from patients with AI-CAH or PBC but not chronic viral hepatitis secreted anti-ASGPR antibodies in vitro. In this study we characterized the influence of liver-infiltrating T cells on the secretion of ASGPR-specific autoantibodies by autologous B cells in cell culture supernatants. T cell clones from liver biopsies of three patients with chronic autoimmune liver disorders (one with AI-CAH, two with PBC) were isolated and investigated for their proliferative response to soluble ASGPR and their helper function provided to autoantibody-secreting B lymphocytes. PBMC from these patients secreted autoantibodies spontaneously in their cell culture supernatants and showed a proliferative response to ASGPR. T cell-depleted PBMC, however, lacked spontaneous antibody secretion. Four CD4+CD8- liver-infiltrating T cell clones showed a proliferative response to ASGPR and also induced spontaneous anti-ASGPR antibody production in cell culture supernatants when added to autologous T cell depleted PBMC. Activated supernatants of these T cell clones failed to induce antibody production. None of seven CD4+CD8- and two CD4-CD8+ T cell clones non-responding to ASGPR provided this help for antibody secretion. Anti-ASGPR secretion in vitro could not be inhibited by the addition of MoAbs raised against monomorphic determinants on HLA class II molecules. The addition of purified ASGPR or polyclonal-activating pokeweed mitogen showed no influence on the production of autoantibodies in these cultures. These data show that B lymphocytes require T cell help for the production of ASGPR-specific antibodies. This help can be provided by ASGPR-responsive T helper cells via cellular interactions. 相似文献
7.
8.
Janneche Utne Skaare Anuschka Polder 《Archives of environmental contamination and toxicology》1990,19(5):640-645
Milk samples of 14 women were analyzed for PCBs (polychlorinated biphenyls),p,p-DDE, and HCB (hexachlorobenzene) during 11 intervals of a 120 day-lactation period. A general downward trend in residue levels was evident, and a statistically significant decline was observed for residue levels of PCBs (P<0.01) and HCB (P=0.02) on the milk fat basis. Primipara (n=9) had from 1.5 to 2.1 times higher mean residue levels than mothers nursing their second or third child (n=9). Significant declines in residue levels during lactation of the first child were found, while no pronounced changes in residue levels were observed during lactation of the second or third child. Overall, residue levels in this study were lower than corresponding levels found earlier in Norway, and within the range of the corresponding levels found in another Norwegian human milk survey done at the same time. 相似文献
9.
One hundred patients undergoing abdominal surgery were included in this prospective study. The role of local application of Betadine, use of synthetic sutures, and use of low pressure subcutaneous suction drainage were evaluated in preventing post-operative wound infection. The infection rate was 15 per cent with Betadine, 15.4 per cent with prolene, 20 per cent with subcutaneous suction drainage and 30.8 per cent in the control group.KEY WORDS: Surgical wound infection, Betadine, Sutures, Infection control 相似文献
10.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献