全文获取类型
收费全文 | 4466篇 |
免费 | 388篇 |
国内免费 | 142篇 |
专业分类
耳鼻咽喉 | 60篇 |
儿科学 | 39篇 |
妇产科学 | 105篇 |
基础医学 | 849篇 |
口腔科学 | 137篇 |
临床医学 | 256篇 |
内科学 | 408篇 |
皮肤病学 | 104篇 |
神经病学 | 259篇 |
特种医学 | 194篇 |
外国民族医学 | 5篇 |
外科学 | 355篇 |
综合类 | 779篇 |
现状与发展 | 1篇 |
预防医学 | 114篇 |
眼科学 | 28篇 |
药学 | 243篇 |
2篇 | |
中国医学 | 44篇 |
肿瘤学 | 1014篇 |
出版年
2024年 | 5篇 |
2023年 | 41篇 |
2022年 | 82篇 |
2021年 | 107篇 |
2020年 | 106篇 |
2019年 | 109篇 |
2018年 | 100篇 |
2017年 | 133篇 |
2016年 | 130篇 |
2015年 | 156篇 |
2014年 | 256篇 |
2013年 | 222篇 |
2012年 | 245篇 |
2011年 | 307篇 |
2010年 | 300篇 |
2009年 | 325篇 |
2008年 | 266篇 |
2007年 | 244篇 |
2006年 | 265篇 |
2005年 | 222篇 |
2004年 | 204篇 |
2003年 | 172篇 |
2002年 | 127篇 |
2001年 | 135篇 |
2000年 | 103篇 |
1999年 | 86篇 |
1998年 | 75篇 |
1997年 | 58篇 |
1996年 | 62篇 |
1995年 | 57篇 |
1994年 | 47篇 |
1993年 | 28篇 |
1992年 | 31篇 |
1991年 | 21篇 |
1990年 | 19篇 |
1989年 | 25篇 |
1988年 | 16篇 |
1987年 | 14篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1984年 | 15篇 |
1983年 | 9篇 |
1982年 | 5篇 |
1981年 | 11篇 |
1980年 | 5篇 |
1978年 | 2篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1974年 | 2篇 |
排序方式: 共有4996条查询结果,搜索用时 0 毫秒
61.
对西京医院进行根治性放疗的食管鳞状细胞癌患者 64例 ,照射剂量DT64~ 70Gy ,进行前瞻性研究 ,对其治疗前活检标本进行SP免疫组化染色 ,计数其阳性细胞数 ,并计算阳性率 ,观察其阳性率与食管癌放疗疗效及预后的关系。结果PCNA阳性率 5 1%~ 67 1% ,中央值 3 2 0 % ,PCNA阳性率 >40 %者较低于此值者预后明显差。p16在低分化癌中较高分化癌阳性表达率低 ,且随着病期的进展阳性表达率降低 ,P <0 0 5 ;Ki 67与近期疗效及预后未见明显差异。初步研究结果提示 ,PCNA阳性率是判断放疗疗效有意义的指标 ,且与p16联合检测对食管鳞癌放疗前恶性程度评定和预后估计有重要意义 相似文献
62.
目的 :探讨结直肠癌组织中Survivin表达的临床病理学意义及其与癌细胞增殖的关系。方法 :免疫组织化学染色方法 (SP法 )检测 10 6例结直肠癌组织中Survivin、Ki 6 7、P5 3的表达 ,分析Survivin表达与Ki 6 7增殖指数、P5 3表达及各临床病理因素的关系。结果 :Survivin阳性表达结直肠癌的Ki 6 7增殖指数 (4 1.31%± 19.83% )明显高于Survivin阴性者 (2 6 .2 1%± 2 0 .36 % ) ,Survivin表达与肿瘤细胞增殖呈正相关 (P <0 .0 5 )。Survivin表达与P5 3表达无显著相关。Survivin在结直肠癌组织中的表达率为 6 4 .2 % (6 8/10 6例 ) ,癌旁形态学正常的结直肠粘膜未见Survivin表达 ;Survivin在中高分化结直肠癌表达阳性率 72 .4 % (6 3/87例 ) ,明显高于低分化结直肠癌 (2 6 .3% ,5 /19例 ) ,P <0 .0 5。此外 ,Survivin表达与患者性别、肿瘤位置、浸润深度、淋巴结转移、远处转移以及Dukes’分期无显著相关 (P >0 .0 5 )。结论 :凋亡抑制蛋白Survivin在结直肠癌组织中阳性表达率为 6 4 .2 % ,与细胞分化程度有关 ,可促进结直肠癌细胞的增殖 相似文献
63.
P21WAF1, P27KIP1, TP53 and C-MYC analysis in 204 ovarian carcinomas treated with platinum-based regimens. 总被引:8,自引:0,他引:8
J Plisiecka-Ha?asa G Karpińska T Szymańska I Zió?kowska R Madry A Timorek J Debniak M U?ańska M Jedryka A Chudecka-G?az M Klimek A Rembiszewska E Kraszewska B Dybowski J Markowska J Emerich A P?uzańska M Goluda I Rzepka-Górska K Urbański J Zieliński J Stelmachów M Chrabowska J Kupryjańczyk 《Annals of oncology》2003,14(7):1078-1085
BACKGROUND: The prognostic and predictive value of cell cycle regulatory proteins in ovarian cancer has not been established. We evaluated the clinical and biological significance of P21(WAF1), P27(KIP1), C-MYC, TP53 and Ki67 expressions in ovarian cancer patients. MATERIALS AND METHODS: Immunohistochemical analysis was performed on 204 ovarian carcinomas of International Federation of Gynecology and Obstetrics (FIGO) stage IIB to IV treated with platinum-based chemotherapy. Multivariate analysis with Cox and logistic regression models was performed in the whole group, and in the TP53-negative and TP53-positive subgroups. RESULTS: High P21(WAF1) labeling index (LI) was an independent positive predictor of platinum-sensitive response (P = 0.02). Overall survival was positively influenced by P21(WAF1) LI (P = 0.02) or by P21(WAF1) plus P27(KIP1) LI (P = 0.004) in the TP53-negative group only. Ki67 LI showed borderline association with disease-free survival (P = 0.05). Growth fraction was negatively associated with P21(WAF1) and P27(KIP1) indices in the TP53-negative group (P = 0.023 and 0.008, respectively), and these associations were borderline or lost in the TP53-positive group. Endometrioid and clear cell carcinomas differed from other carcinomas by having a low incidence of TP53 accumulation, a high incidence of C-MYC overexpression (70%) and a low median Ki67 LI (all with P <0.001). CONCLUSIONS: We have shown an independent predictive value of P21(WAF1) LI in ovarian carcinoma patients. The prognostic value of P21(WAF1) and P21(WAF1) plus P27(KIP1) LI was determined by TP53 status. A high frequency of C-MYC overexpression in endometrioid and clear cell carcinomas may suggest its role in the development of these tumor types. 相似文献
64.
Michael Crump Carol A. Sawka Gerrit DeBoer Roger B. Buchanan James N. Ingle John Forbes J. William Meakin Wendy Shelley Kathleen I. Pritchard 《Breast cancer research and treatment》1997,43(3):201-210
Increased dietary fat intake and rate of breastepithelial cell proliferation have each been associated withthe development of breast cancer. The goal ofthis study was to measure the effect ofa low fat, high carbohydrate diet on therate of breast epithelial cell proliferation in womenat high risk for breast cancer. Women wererecruited from the intervention and control groups ofa randomized low fat dietary intervention trial, breastepithelial cells were obtained by fine needle aspiration,and cell proliferation was assessed in these samplesusing immunofluorescent detection of Ki-67 and PCNA. Theeffects of needle size and study group oncell yield and cytologic features of the cellswere also examined. Fifty three women (20 inthe intervention group and 33 in the controlgroup) underwent the biopsy procedure. Slides from 38subjects were stained for Ki-67 and from 14subjects for PCNA. No cell proliferation (fluorescence) wasdetected for either Ki-67 or PCNA in anyof the slides. Epithelial cell yield and numberof stromal fragments were greater with a largerneedle size. Numbers of stromal fragments and bipolarnaked nuclei were greater in the low fatas compared to the control group but nodifferences in epithelial cell yield were observed betweenthe two groups. This study confirms that fineneedle aspiration biopsy is a feasible method ofobtaining epithelial cells from women without discrete breastmasses, but suggests that cell proliferation cannot beassessed using Ki-67 and PCNA in such samples. 相似文献
65.
An association has previously been reported between exposure to medical diagnostic ionizing radiation and papillary thyroid cancer in women. To further evaluate potential mechanisms in carcinogenesis, the expression of p53, c-erbB-2, as well as Ki-67, estrogen and progesterone receptors were analyzed by immunohistochemistry in 19 women exposed to X-rays and for comparison in nine women without such reported exposure. They all had papillary thyroid cancer. No difference was found between these groups. The results of this study showed that p53, c-erbB-2, Ki-67, estrogen and progesterone receptors are not involved in papillary thyroid cancer associated with exposure to medical diagnostic ionizing radiation. 相似文献
66.
67.
应用组织芯片技术研究bcl-10、TopoⅡα及Ki-67在MALT型淋巴瘤中的表达和意义 总被引:2,自引:0,他引:2
目的应用组织芯片技术研究bcl蛳10、TopoⅡα及Ki蛳67在MALT型淋巴瘤中的表达及意义。方法建立包含84例MALT型淋巴瘤、7例弥漫性大B细胞淋巴瘤(DLBCL)、17例其他肿瘤及18例淋巴结反应性增生,共252点阵的组织芯片,应用免疫组织化学技术(S蛳P法)检测bcl蛳10、TopoⅡα及Ki蛳67在MALT型淋巴瘤中的表达。结果Ki蛳67、TopoⅡα的表达在ⅠE期与Ⅱ2E+Ⅲ期之间差异有显著性(P<0.05),并且与临床分期呈正相关(r=0.423,P=0.000;r=0.299,P=0.016)。淋巴结反应性增生中生发中心B细胞胞质大量表达bcl蛳10,边缘区中等量表达,在套区B细胞较少表达;在MALT淋巴瘤中,bcl蛳10核型表达7例(8.33%),胞质型表达27例(32.14%)。bcl蛳10胞质表达在低度和高度恶性MALT型淋巴瘤中差异有显著性(P<0.05);但与临床分期无关。核型表达者与肿瘤细胞浸润有关。结论MALT型淋巴瘤中TopoⅡα与Ki蛳67的作用相似,它们可作为预后评价的指标。bcl蛳10表达广泛地存在于MALT型淋巴瘤中,该基因异常表达可能与肿瘤恶性程度有关,可作为判断预后的指标之一,核表达可能与病情的进展有关,与肿瘤侵袭行为有关。 相似文献
68.
神经母细胞瘤血管内皮细胞生长因子、Ki-67抗原表达及微血管密度研究 总被引:1,自引:0,他引:1
目的 探讨血管内皮细胞生长因子(VEGF)、瘤内微血管密度(MVD)与神经母细胞瘤(NB)细胞增殖及预后的关系。方法 采用S-P免疫组化法,检测VEGF、CD34和Ki-67抗原在21例NB中的表达及MVD计数。结果 VEGF及Ki-67表达与NB病理分型及核分裂指数有关(P〈0.05或P〈0.01),而与NB分化与否、肿瘤大小及性别无关。MVD值在临床各病理参数间差异无显著意义。VEGF表达与MVD值、VEGF与Ki-67表达呈明显正相关(P〈0.01)。结论 VEGF、Ki-67表达与NB细胞增殖及预后密切相关。 相似文献
69.
Proliferation, Vascular Endothelial Growth Factor Expression and Cavernous Sinus Invasion in Growth Hormone Secreting Pituitary Adenomas 总被引:4,自引:0,他引:4
Summary Surgical cure of growth hormone producing pituitary adenomas (GHomas) becomes difficult when they invade the cavernous sinus
(CS). Tumour proliferative activity and angiogenesis are thought to be required for tumour growth and invasion, and vascular
endothelial growth factor (VEGF) activates neovascularization around tumours. In this study, the mechanism and clinical significance
of CS invasion is analysed. In 25 surgically treated GHomas, the extent of CS invasion was classified as high (Knosp's grade
3 and 4), and low (grade 0, 1 and 2) MR grades, and the MR grades were compared with tumour proliferative potential (Ki-67
expression), angiogenetic demand (VEGF expression), volume of adenomas and serum hormone levels.
The Ki-67 index of high MR grade adenomas (1.17±0.62%) was significantly higher than that of low MR grade adenomas (0.55±0.42%,
p=0.027), whereas VEGF expression showed no significant correlation with MR grades (p>0.999). Tumour volume also showed a
significant correlation with MR grade (p=0.002). VEGF expression was not correlated with serum hormone level and volume, but
was correlated with tumour proliferative potential. Proliferative potential and tumour volume were two independent factors
related to CS invasion. Although VEGF expression was not a direct factor related to CS invasion, it may indirectly play a
role in activation of tumour aggressiveness, which is required in CS invasion.
Our results show that high MR grade adenomas have higher proliferative ability. In order to improve the surgical outcome,
pre-operative medical debulking is indicated, particularly, in such adenomas. 相似文献
70.
胃肠道间质瘤中PCNA和 Ki-67的表达及其意义 总被引:1,自引:0,他引:1
目的探讨PCNA和Ki-67的表达与胃肠道间质瘤(GIST)临床病理学特征的关系及其相关性。方法应用免疫组化SP法观察40例胃肠道间质瘤中PCNA和Ki-67的表达。结果40例GIST中有26例表达PCNA,24例表达Ki-67,阳性表达率分别为65.0%和60.0%。PCNA和Ki-67的表达与组织学分级有关(P<0.01),两者的表达具有正相关性(r=0.471)。结论PCNA和Ki-67在胃肠道间质瘤的发生、发展中发挥作用,两者可作为判断GIST良恶性的客观指标。 相似文献