全文获取类型
收费全文 | 1144篇 |
免费 | 55篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 40篇 |
妇产科学 | 108篇 |
基础医学 | 151篇 |
口腔科学 | 63篇 |
临床医学 | 60篇 |
内科学 | 99篇 |
皮肤病学 | 23篇 |
神经病学 | 27篇 |
特种医学 | 39篇 |
外科学 | 169篇 |
综合类 | 110篇 |
一般理论 | 1篇 |
预防医学 | 45篇 |
眼科学 | 14篇 |
药学 | 45篇 |
中国医学 | 3篇 |
肿瘤学 | 194篇 |
出版年
2023年 | 8篇 |
2022年 | 12篇 |
2021年 | 23篇 |
2020年 | 18篇 |
2019年 | 23篇 |
2018年 | 24篇 |
2017年 | 13篇 |
2016年 | 8篇 |
2015年 | 16篇 |
2014年 | 34篇 |
2013年 | 40篇 |
2012年 | 65篇 |
2011年 | 60篇 |
2010年 | 64篇 |
2009年 | 43篇 |
2008年 | 78篇 |
2007年 | 61篇 |
2006年 | 68篇 |
2005年 | 65篇 |
2004年 | 57篇 |
2003年 | 45篇 |
2002年 | 54篇 |
2001年 | 52篇 |
2000年 | 30篇 |
1999年 | 45篇 |
1998年 | 15篇 |
1997年 | 23篇 |
1996年 | 14篇 |
1995年 | 4篇 |
1994年 | 20篇 |
1993年 | 4篇 |
1992年 | 14篇 |
1991年 | 9篇 |
1990年 | 14篇 |
1989年 | 24篇 |
1988年 | 17篇 |
1987年 | 4篇 |
1986年 | 8篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1981年 | 3篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1975年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1968年 | 2篇 |
排序方式: 共有1208条查询结果,搜索用时 382 毫秒
1.
2.
P. G. Ngan S. Jayagopal E. N. George D. McGeorge A. Juma 《European journal of plastic surgery》2007,30(4):189-194
A survey was carried out to ascertain the preference for donor site scar orientation in patients undergoing pedicled latissimus
dorsi breast reconstruction and their views on breast reconstruction in general. One hundred twelve women (59 Chinese, 53
Western) completed the questionnaire. Participants were asked to state their preferred scar orientation (i.e., oblique, horizontal,
or vertical) based on photographs showing the position of the scars. Demographic information and views on issues surrounding
breast reconstruction in general were also collected. Data was analyzed non-parametrically with chi-square test and t test. The mean age of participants was 39.5 years (20–73 years). Seventy-seven percent of the participants would opt for
an immediate breast reconstruction if offered (p < 0.001). Eighty-six percent would have objection to the use of silicone implant as a whole or part of a reconstruction (p < 0.001). Vertical and horizontal scars were the preferred orientation, with no women choosing the oblique orientation as
their first choice (p < 0.001). The non-Chinese of 40 years or older, as well as Chinese women from all age groups, preferred the horizontal scar
(p < 0.05). We demonstrated that both culture and age impact on the preferred scar orientation in breast reconstruction. Women
in the age group we commonly reconstruct favored the horizontal scar. However, the younger women of non-Chinese origin tended
to favor the vertical scar. 相似文献
3.
4.
Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to
the lung, liver, and, less frequently, to the brain. Renal involvement is rare. Magnetic resonance imaging (MRI) is a useful
modality to image the affected tissues; it contributes to the evaluation and management of the disease. One case of renal
choriocarcinoma with MRI evaluation is reported.
Received: 24 February 1997/Accepted: 14 April 1997 相似文献
5.
6.
Assessment of cell proliferation in hydatidiform mole using monoclonal antibody MIB1 to Ki-67 antigen. 总被引:4,自引:2,他引:4 下载免费PDF全文
AIMS--To assess the role of Ki67 immunoreactivity in predicting the clinical progress of hydatidiform mole. METHODS--Tissue from 87 hydatidiform moles, 11 normal first trimester placentas, 11 normal term placentas and 17 spontaneous abortions were examined for expression of Ki67 antigen, using the monoclonal antibody MIB1. RESULTS--Ki67 immunoreactivity was significantly higher in the tissue from normal first trimester placentas than in that from normal term placentas and spontaneous abortions. Among the 87 patients with hydatidiform moles studied, 20 developed persistent gestational trophoblastic disease and required subsequent treatment. There was no statistically significant difference in the Ki67 index between the 20 patients who developed persistent disease and those who did not. CONCLUSION--Hydatidiform moles which give rise to persistent trophoblastic disease do not have a higher proliferative rate than those which do not. The Ki67 index is not useful for predicting the prognosis of molar pregnancies. 相似文献
7.
Expression of c-myc and c-fms oncogenes in trophoblastic cells in hydatidiform mole and normal human placenta. 总被引:3,自引:0,他引:3 下载免费PDF全文
A N Cheung G Srivastava S Pittaluga T K Man H Ngan R J Collins 《Journal of clinical pathology》1993,46(3):204-207
AIMS: To compare the expression of c-myc and c-fms proto-oncogenes in the placenta and hydatidiform mole. METHODS: Twelve hydatidiform moles and six induced abortion cases were collected. c-myc and c-fms proto-oncogene expression was analysed by northern blot hybridisation and immunohistochemical staining. RESULTS: The results of northern blot hybridisation analysis showed that c-fms was expressed more strongly in hydatidiform moles compared with normal placenta of similar gestational age. Moreover, c-fms mRNA concentrations increased with more advanced gestational age in moles but not in normal placentas. c-myc expression was very low in hydatidiform moles and normal placentas. Both oncogenes, however, had no direct correlation with the clinical course of the molar pregnancies. CONCLUSION: The difference in c-fms expression between hydatidiform moles and normal placentas suggests that c-fms may have a role in the development of molar pregnancies. 相似文献
8.
Expression in non-Hodgkin's lymphoma of the bcl-2 protein associated with the t(14;18) chromosomal translocation 总被引:20,自引:0,他引:20
B Y Ngan Z Chen-Levy L M Weiss R A Warnke M L Cleary 《The New England journal of medicine》1988,318(25):1638-1644
For many non-Hodgkin's lymphomas, the bcl-2 gene has been implicated as a likely proto-oncogene, since it is consistently located at or near the breakpoint sites of t(14;18) chromosomal translocations. To define the role of the protein product of the bcl-2 gene in lymphoid cancers, we used anti-bcl-2 antibodies to perform immunohistochemical studies of frozen sections of 136 tissue specimens affected by lymphoma or non-neoplastic lymphoid disorders. Immunoreactive bcl-2 protein was observed in the neoplastic cells in almost all the follicular lymphomas, whereas no bcl-2 protein was detected in follicles affected by non-neoplastic processes or in normal lymphoid tissue. Every tumor with molecular-genetic evidence of t(14;18) translocation expressed detectable levels of bcl-2 protein, regardless of whether the breakpoint was located in or at a distance from the bcl-2 gene. These data show consistent expression of a proto-oncogenic protein in a large proportion of non-Hodgkin's lymphomas and provide further support of a role for bcl-2 in the pathogenesis of all lymphomas with the t(14;18) karyotypic abnormality. Increased expression of bcl-2 after t(14;18) translocations may be a specific marker for B-cell cancers, and demonstration of the protein with use of anti-bcl-2 antibodies could be useful in the diagnosis of many non-Hodgkin's lymphomas. 相似文献
9.
Monocytoid B-cell lymphoma: a study of 36 cases 总被引:3,自引:0,他引:3
We have studied 36 cases of monocytoid B-cell lymphoma (MBCL). We confirm the predilection for females (30 of 36; ratio, five women to one man). The median age was 65 years (range, 29 to 85 years). Monocytoid B-cell lymphoma characteristically involves peripheral lymph nodes (30 of 36) with a propensity for paraparotid or intraparotid nodes. Salivary glands were affected in five patients. Other extranodal sites of involvement included breast, thyroid, stomach, and soft tissue of chest wall. Eight patients manifested with Sj?gren's syndrome, one had systemic lupus erythematosus, one presented initially with Raynaud's phenomenon, and two had a monoclonal gammopathy. "Composite lymphomas" were encountered in seven patients. In addition, association with or progression to a higher-grade lymphoma, ie, mixed small and large cell (one) and large cell (six), was observed in seven patients and was associated with a more aggressive behavior of the lymphoma. Immunohistochemical studies performed on biopsy sections from 20 patients confirmed the B-cell nature of MBCL. An average reactivity of less than 10% of the monocytoid B cells with the proliferation marker Ki-67 was demonstrated, in keeping with the indolent behavior of MBCL. Despite our observation of follicular lymphomas frequently accompanying MBCL, the t(14;18) chromosomal translocation does not appear to play a pathogenetic role for MBCL, as determined by molecular studies for the t(14;18) chromosomal translocation and immunologic studies for the BCL2 protein. Our observations also provide support for the proposal that there is an overlap between MBCL and "MALT lymphomas" (those arising from mucosa-associated lymphoid tissue). 相似文献
10.
Replicative MCM7 protein as a proliferation marker in endometrial carcinoma: a tissue microarray and clinicopathological analysis 总被引:3,自引:0,他引:3
Li SS Xue WC Khoo US Ngan HY Chan KY Tam IY Chiu PM Ip PP Tam KF Cheung AN 《Histopathology》2005,46(3):307-313
AIMS: To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues. METHODS AND RESULTS: Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50). CONCLUSIONS: In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients. 相似文献