全文获取类型
收费全文 | 469篇 |
免费 | 33篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 17篇 |
妇产科学 | 25篇 |
基础医学 | 58篇 |
口腔科学 | 7篇 |
临床医学 | 39篇 |
内科学 | 95篇 |
皮肤病学 | 2篇 |
神经病学 | 4篇 |
特种医学 | 99篇 |
外科学 | 32篇 |
综合类 | 41篇 |
预防医学 | 20篇 |
眼科学 | 5篇 |
药学 | 16篇 |
中国医学 | 1篇 |
肿瘤学 | 37篇 |
出版年
2021年 | 3篇 |
2017年 | 4篇 |
2015年 | 6篇 |
2014年 | 9篇 |
2013年 | 13篇 |
2012年 | 10篇 |
2011年 | 10篇 |
2010年 | 12篇 |
2009年 | 14篇 |
2008年 | 10篇 |
2007年 | 23篇 |
2006年 | 14篇 |
2005年 | 12篇 |
2004年 | 14篇 |
2003年 | 13篇 |
2002年 | 11篇 |
2001年 | 9篇 |
2000年 | 11篇 |
1999年 | 7篇 |
1998年 | 16篇 |
1997年 | 15篇 |
1996年 | 13篇 |
1995年 | 5篇 |
1994年 | 14篇 |
1993年 | 4篇 |
1992年 | 8篇 |
1991年 | 10篇 |
1990年 | 10篇 |
1989年 | 19篇 |
1988年 | 17篇 |
1987年 | 20篇 |
1986年 | 30篇 |
1985年 | 14篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 7篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1978年 | 4篇 |
1977年 | 10篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1972年 | 3篇 |
1971年 | 4篇 |
1969年 | 3篇 |
1965年 | 4篇 |
1963年 | 3篇 |
1928年 | 2篇 |
排序方式: 共有503条查询结果,搜索用时 15 毫秒
21.
22.
Dvorak AM; Tepper RI; Weller PF; Morgan ES; Estrella P; Monahan-Earley RA; Galli SJ 《Blood》1994,83(12):3600-3612
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo. 相似文献
23.
Kimberley L. Kaufman Swetlana Mactier Nicola J. Armstrong Duthika Mallawaaratchy Scott N. Byrne Lauren E. Haydu Valerie Jakrot John F. Thompson Graham J. Mann Richard A. Scolyer Richard I. Christopherson 《Clinical & experimental metastasis》2014,31(4):407-421
There is an urgent need to identify more accurate prognostic biomarkers in melanoma patients, particularly in those with metastatic disease. This study aimed to identify melanoma and leukocyte surface antigens predictive of survival in a prospective series of AJCC stage IIIb/c melanoma patients (n = 29). Live cell suspensions were prepared from melanoma metastases within lymph nodes (LN). The suspensions were immuno-magnetically separated into CD45+ (leukocyte) and CD45? (non-hematopoietic, enriched melanoma cell) fractions. Surface antigens on CD45? and CD45+ cell populations were profiled using DotScan? microarrays (Medsaic Pty. Ltd.) and showed differential abundance levels for 52 and 78 antigens respectively. Associations of the surface profiles with clinicopathologic and outcome data (median follow-up 35.4 months post LN resection) were sought using univariate (log-rank test) and multivariate (Wald’s test; modelled with patient’s age, gender and AJCC staging at LN recurrence) survival models. CD9 (p = 0.036), CD39 (p = 0.004) and CD55 (p = 0.005) on CD45+ leukocytes were independently associated with distant metastasis-free survival using multivariate analysis. Leukocytes with high CD39 levels were also significantly associated with increased overall survival (OS) in multivariate analysis (p = 0.016). LNs containing leukocytes expressing CD11b (p = 0.025), CD49d (p = 0.043) and CD79b (p = 0.044) were associated with reduced OS on univariate analysis. For enriched melanoma cells (CD45? cell populations), 11 surface antigens were significantly correlated with the disease-free interval (DFI) between diagnosis of culprit primary melanoma and LN metastasis resection. Nine antigens on CD45+ leukocytes also correlated with DFI. Following validation in independent datasets, surface markers identified here should enable more accurate determination of prognosis in stage III melanoma patients and provide better risk stratification of patients entering clinical trials. 相似文献
24.
Grossman RI; Braffman BH; Brorson JR; Goldberg HI; Silberberg DH; Gonzalez- Scarano F 《Radiology》1988,169(1):117-122
Thirteen patients with definite multiple sclerosis (MS), studied 16-24 months previously with magnetic resonance (MR) imaging with and without enhancement by intravenously administered gadolinium diethylenetriaminepentaacetic acid (DTPA) dimeglumine, were reexamined with a similar protocol. Assessment of enhancement and clinical activity in both studies revealed that enhancement was observed in 13 of 14 cases in which clinical activity had changed within 4 weeks of the study and thus appeared more sensitive than clinical examination in determining active disease. The 3-minute postinjection, short repetition time image (TR) was the most efficient for depicting enhancement. Enhancing lesions (active plaques) arose from previously hyper- or isointense regions on long TR images. Previously active lesions reverted to areas of iso- or hyperintensity on long TR images. Serial comparison of long TR images in this population reveals a decrease in high-intensity lesions on long TR images in some cases and an increase in others. The findings of high-intensity regions on long TR images and previously enhancing lesions both becoming isointense suggests that transient inflammatory changes with concomitant edema without demyelination and/or with significant remyelination may occur in some MS lesions. MS lesions are dynamic; both active and inactive lesions may show dramatic change on longitudinal MR imaging studies. 相似文献
25.
Joseph L. Kelley III Amal Kanbour-Shakir Scott L. Williams Wayne A. Christopherson 《Gynecologic oncology》1991,43(3):291-294
Metastatic disease presenting in the mammary gland from gynecologic malignancies is a rare occurrence. A case of metastatic adenosquamous carcinoma of the cervix presenting as an inflammatory breast lesion is reported. Metastases within the breast have distinct clinical, radiographic, and histologic features and should be suspected in a patient with a breast mass and a known extramammary primary. As with other distant metastases of cervical cancer, mammary gland involvement portends a poor prognosis. 相似文献
26.
A case report of a patient with recurrent squamous cell carcinoma of the cervix is presented in whom the recurrence was confined to the gastrointestinal tract and omentum in the upper abdomen. No evidence of recurrent disease was present in the pelvis or paraaortic lymph node bearing areas. Possible mechanisms for this unusual location of recurrence are discussed. 相似文献
27.
S Niesert W Christopherson K Korte M D Mitchell P C MacDonald M L Casey 《American journal of obstetrics and gynecology》1986,155(6):1348-1352
Amnion is believed to be a tissue of central importance in the biochemical processes of parturition. In this tissue, prostaglandin E2 is the near exclusive prostaglandin produced. And although the production of prostaglandin E2 is increased during labor in women, the levels of the major metabolite of prostaglandin E2 in maternal plasma are not elevated; rather, the levels of 13,14-dihydro-15-ketoprostaglandin F2 alpha, the major circulating metabolite of prostaglandin F2 alpha, are increased strikingly. Because of this apparent paradox, we considered the possibility that prostaglandin E2, originating in amnion, chorion laeve, or decidua vera, is converted to prostaglandin F2 alpha in decidua vera by the action of prostaglandin E2-9-ketoreductase. We found that prostaglandin E2 9-ketoreductase, the enzyme that catalyzes the conversion of prostaglandin E2 to F2 alpha, is present in cytosolic fractions prepared from homogenates of uterine decidua vera tissue. The specific activity of 9-ketoreductase in cytosolic fractions of decidua of six women varied from 3.2 to 155 pmol X min-1 X mg-1 protein. We also evaluated the conversion of exogenous prostaglandin E2 to F2 alpha in intact human endometrial stromal cells in monolayer culture. We found that prostaglandin E2, added to the culture medium, was converted to prostaglandin F2 alpha by endometrial stromal cells that were maintained in the presence of inhibitors of prostaglandin synthase. The extent of conversion of exogenous prostaglandin E2 to F2 alpha, however, was low relative to the specific activity of prostaglandin E2 9-ketoreductase found in decidual cytosol. These findings are consistent with the possibility that prostaglandin E2 formed in decidua vera tissue may be converted in that tissue to prostaglandin F2 alpha by 9-ketoreductase; on the other hand, prostaglandin E2 formed in contiguous tissues probably is not converted significantly to prostaglandin F2 alpha by decidual 9-ketoreductase. 相似文献
28.
Haberichter SL Jozwiak MA Rosenberg JB Christopherson PA Montgomery RR 《Arteriosclerosis, thrombosis, and vascular biology》2002,22(6):921-926
The von Willebrand factor (VWF) propeptide (VWFpp) is critical for the targeting of VWF multimers to storage granules. VWFpp alone efficiently navigates the storage pathway in AtT-20 and endothelial cells and chaperones mature VWF multimers to storage granules when the two proteins are expressed in cis or in trans. To further define the role of VWFpp in granular sorting, we examined its ability to sort an unrelated protein, C3alpha into the regulated secretory pathway. Chimeric constructs of VWFpp and the alpha-chain of C3 were developed. The C3alpha protein expressed alone did not sort to granules in AtT-20 cells. The trans expression of C3alpha and VWFpp resulted in granular storage of VWFpp but no corresponding storage of C3alpha. When C3alpha is expressed as a single chain molecule with VWFpp that was rendered uncleavable by furin, C3alpha is re-routed to storage and is colocalized with VWFpp. The uncleavable protein was expressed in bovine aortic endothelial cells where it sorted to Weibel-Palade bodies, colocalized with bovine VWF, and was released when agonist stimulated. We now demonstrate that VWFpp re-routes a constitutively secreted protein to the regulated storage pathway. Furthermore, our studies suggest that the VWFpp storage signal is contained within amino acids 201 to 741. 相似文献
29.
30.
MB Viana M Murao G Ramos HM Oliveira RI de Carvalho M de Bastos EA Colosimo WS Silvestrini 《Archives of disease in childhood》1994,71(4):304-310
One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries. 相似文献