全文获取类型
收费全文 | 1239篇 |
免费 | 150篇 |
国内免费 | 41篇 |
学科分类
医药卫生 | 1430篇 |
出版年
2023年 | 9篇 |
2022年 | 17篇 |
2021年 | 28篇 |
2020年 | 32篇 |
2019年 | 35篇 |
2018年 | 44篇 |
2017年 | 51篇 |
2016年 | 39篇 |
2015年 | 68篇 |
2014年 | 95篇 |
2013年 | 84篇 |
2012年 | 76篇 |
2011年 | 93篇 |
2010年 | 101篇 |
2009年 | 76篇 |
2008年 | 67篇 |
2007年 | 69篇 |
2006年 | 69篇 |
2005年 | 62篇 |
2004年 | 48篇 |
2003年 | 57篇 |
2002年 | 46篇 |
2001年 | 56篇 |
2000年 | 27篇 |
1999年 | 21篇 |
1998年 | 12篇 |
1997年 | 8篇 |
1996年 | 11篇 |
1995年 | 6篇 |
1994年 | 9篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有1430条查询结果,搜索用时 15 毫秒
1.
目的 对多激素分泌性垂体泌乳素腺瘤的克隆状态以及激素分泌谱进行分析。方法 对26例女性垂体泌乳素腺瘤患者(单激素分泌性PRL腺瘤7例,多激素分泌性PRL腺瘤19例)进行肿瘤标本的免疫组化分析,并且提取DNA行HUMARA分析。结果免疫组化分析提示本组多激素分泌性垂体PRL腺瘤具有10种不同的激素分泌谱,现代分子生物学HUMARA克隆分析提示11/13例(85%)多激素分泌性垂体PRL腺瘤为单克隆起源。结论 结果提示垂体泌乳素腺瘤除了分泌泌乳素外,还可以分泌多种垂体激素,而且绝大多数多激素分泌性垂体腺瘤的起源是单克隆性的。 相似文献
2.
A correlation between apoptosis and proliferation in astrocytomas and oligodendrogliomas, but not in glioblastomas, has been previously reported. An index for apoptosis and proliferation was established for each tumor in a series of 20 brain metastases, and its correlation was studied using the Spearman rank correlation test. Apoptosis index (AI) ranged between 1 and 78% (mean ± SD: 11.48 ± 16.4). Proliferation index (PI) ranged between 2.4 and 21% (mean ± SD: 8.23 ± 4.8). When the relationship between AI and PI was studied, a clear correlation was found (r: 0.8965, 95% CI: 0.74–0.95; P < 0.0001). Therefore, it is concluded that a clear correlation exists between proliferation and apoptosis in secondary tumors of the brain. 相似文献
3.
膀胱尿路上皮癌MMP-2表达及其与FAK、p53、bcl-2、Ki-67的关系 总被引:16,自引:1,他引:16
目的 比较不同分化和浸润程度膀胱尿路上皮癌MMP—2表达及其与FAK、p53、bcl—2和Ki—67的关系。方法 采用免疫组化EnVision法对83例膀胱尿路上皮癌和68例非肿瘤尿路上皮,进行MMP—2、FAK、p53、bcl—2和Ki—67的表达检测。结果 MMP—2在肿瘤组织中的表达显著高于非肿瘤性移行上皮,其表达强度随肿瘤分化程度降低和浸润深度增加而显著增强。分化差和浸润性膀胱癌中FAK和p53表达增强,并与MMP—2表达呈正相关;分化差膀胱癌中Ki—67表达增强而bcl—2表达丢失,Ki—67与MMP—2表达呈正相关。结论 在膀胱尿路上皮癌的进展和分化过程中,肿瘤分化程度越低,肿瘤细胞分泌MMP—2越多,其浸润和转移的能力也越强。FAK、p53、Ki—67和bcl—2不但与肿瘤细胞的生长密切相关,还可能直接或间接地参与了MMP—2的调控。 相似文献
4.
M. M. F. J. Tinnemans M.-H. J. H. Lenders F. C. S. Ramaekers B. Schutte G. P. M. ten Velde S. S. Wagenaar G. H. Blijham 《Virchows Archiv : an international journal of pathology》1995,427(3):295-301
In a series of 44 bronchial biopsies from patients suspected of having endobronchial lung carcinoma, the validity of proliferating cell nuclear antigen (PCNA) and Ki67 antigen as proliferative indicators was evaluated in ethanol fixed, paraffin embedded tissue. The percentages of cells positive for these markers were compared to the in vivo bromodeoxyuridine (BrdU) labelling index. A good correlation was found between PCNA immunoreactivity and BrdU labelling index, while Ki67-antigen expression showed a significant relation with BrdU labelling index and with PCNA expression. All three parameters showed a trend towards similar values for the individual cases. Based on the fact that Ki67 antigen is expressed in all cycling cells, whereas replicon-associated PCNA and BrdU only reflect the S-phase fraction, the differences between Ki67-antigen scores on the one hand and BrdU and PCNA scores on the other were smaller than expected. In order to determine the degree of concordance between immunohistochemically and flow cytometrically detected proliferation variables, BrdU incorporation was measured using both methods in duplicate bronchial specimens. Discrepancies in labelling indices were observed predominantly in DNA diploid samples, with consistently lower values in the flow cytometrically analysed specimens. In tumour specimens with an aneuploid DNA content, flow cytometric determination of proliferative activity yielded results similar to those obtained by tissue section examination. We conclude that the scores for PCNA and Ki67 antigen, immunohistochemically detected in ethanol fixed, paraffin embedded tissue reflect functional proliferative activity. 相似文献
5.
The increasing availability of means for the early detection of prostatic cancer has brought under scrutiny the criteria used for prognosis and emphasized our limitations in understanding what determines the rate of progression in these cancers. The rate of cancer cell proliferation has been under intense investigation, which, however, has yielded conflicting results. In this study we evaluated the proliferative activity of benign and neoplastic prostatic epithelium, using various existing methodologies. We first analysed the variability introduced by the methodological approach and then attempted to demonstrate whether determination of the proliferative capacity had any clinical consequence that complemented the histological grading. Tissue samples from patients, 88 with cancer and 46 with benign prostatic pathology, were studied using in vitro bromodeoxyuridine (BrdU) incorporation as well as Ki67 and the proliferating cell nuclear antigen (PCNA) to estimate the proliferative activity. Increased proliferation was found consistently in inflammation and metaplasia, but not in hyperplasia. In contrast, cancers showed marked variability. Although average proliferation indices increased with grade, there was a wide scatter of values. Correlation was stronger with stage, but also depended on the methodology. Bromodeoxyuridine indices over 10 per mille had a positive predictive value of 79 per cent for cancers extending beyond the prostatic capsule and may prove particularly helpful for evaluating patients with grade 7 cancer. This observation is significant, since grade 7 cancers are the most frequent and the least predictable. 相似文献
6.
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
7.
A. D'Errico W. F. Grigioni M. Fiorentino P. Baccarini G. L. Grazi A. M. Mancini 《Pathology international》1994,44(9):682-687
The overexpression of p53 protein and the Ki67 proliferative index was evaluated in 96 hepatocellular carcinomas (HCC), 67 in cirrhotic livers and 29 in non-cirrhotic ones, and in 13 non-carcinomatous lesions, all surgically resected from Italian patients. Overexpression of p53 was detected only in carcinomatous lesions, and was significantly related to the grade of HCC ( P < 0.001). In fact, p53 was observed in 7/7 (100%) cases of grade IV, 13/43 (30.3%) of grade III, and 10/ 46 (21.7%) of grade II. The relationship between p53 and Ki67 scores was determined in serial sections from corresponding areas of both diffuse and patchy immunoreactivity. In the overall population, p53-positive tumors showed a significantly higher Ki67 score (15.9 ± 5.5% vs 9.2 ± 4.3% [ P < 0.001]). This observation was evident in all grades of HCC. 相似文献
8.
Thomas Scholzen Elmar Endl Claudia Wohlenberg Sjaak van der Sar Ian G Cowell Johannes Gerdes Prim B Singh 《The Journal of pathology》2002,196(2):135-144
The expression of the nuclear protein Ki-67 (pKi-67) is strictly correlated with cell proliferation. Because of this, anti-Ki-67 antibodies can be used as operational markers to estimate the growth fraction of human neoplasia in situ. For a variety of tumours, the assessment of pKi-67 expression has repeatedly been proven to be of prognostic value for survival and tumour recurrence, but no cellular function has yet been ascribed to the Ki-67 protein. This study shows that a C-terminal domain of pKi-67 (Kon21) is able to bind to all three members of the mammalian heterochromatin protein 1 (HP1) family in vitro and in vivo. This interaction can be manipulated in living cells, as evidenced by ectopic expression of GFP-tagged HP1 proteins in HeLa cells, which results in a dramatic relocalization of endogenous pKi-67. Taken together, the data presented in this study suggest a role for pKi-67 in the control of higher-order chromatin structure. 相似文献
9.
目的 探讨肿瘤坏死因子诱导蛋白8样蛋白2(TIPE2)、细胞增殖核抗原Ki67在子宫内膜癌组织中的表达及对患者预后的评估价值。方法 选取2018年1月至2020年1月河北工程大学附属医院妇科收治的子宫内膜癌患者120例作为观察组,另选取同期收治的非子宫内膜癌患者130例作为对照组,所有入组患者均接受手术治疗。回顾性收集患者的临床及病理资料,比较两组患者子宫内膜组织中TIPE2、Ki67的表达水平。同时定期对观察组患者进行随访,分析患者2年生存情况,通过Cox比例风险回归模型分析子宫内膜癌患者预后的影响因素。结果 观察组、对照组子宫内膜组织中TIPE2阳性率分别为28.33%、71.54%。与对照组相比,观察组子宫内膜组织TIPE2阳性率降低(P<0.05);观察组、对照组子宫内膜组织中Ki67阳性率分别为33.33%、5.38%。观察组子宫内膜组织Ki67阳性率高于对照组(P<0.05)。对120例子宫内膜癌患者随访2年,至随访结束,93例患者存活,生存率77.50%。Cox模型分析结果显示,TIPE2阴性(HR=3.736,95%CI=1.016~13.157)为子宫内膜... 相似文献
10.
The Expression of the antiapoptotic oncoprotein BCL-2 and its correlation to tumor grade in 62 meningiomas (48 classic, 9
atypical, and 5 anaplastic) using single and double immunohistochemistry was investigated. BCL-2 expression was found in two
different cell populations identified as lymphocytes (BCL-2+CD3+) and tumor cells (BCL+/CD3–). Tumor-infiltrating lymphocytes
(TIL) (CD3+) were found within classic (9.5% of cells), atypical (2.4% of cells), and anaplastic (1.8% of cells) meningiomas.
In classic meningiomas, 66.5% of TIL were BCL-2-positive, in atypical meningiomas 79.2%, and in anaplastic meningiomas 37.9%.
In 33 (68.8%) of the classic meningiomas, medium to high counts of BCL-2+ tumor cells were detected. Atypical meningiomas
showed nearly equal percentages of high (two patients), medium (five patients), and low (two patients) BCL-2+ tumor cell counts,
whereas anaplastic meningiomas showed only medium (two patients) and low (three patients) BCL-2 tumor cell counts or were
BCL-2-negative (one patient). In summary, a significant inverse correlation between the number of BCL-2-positive tumor cells
and tumor grade in meningiomas was found. These findings support the hypothesis of cell survival prolongation by the antiapoptotic
ability of BCL-2 proto- oncogenes and demonstrate the prognostic relevance of BCL-2 immunoreactivity in meningiomas.
Received: 10 June 1998 / Accepted: 23 February 1999 相似文献