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1.
Liu J  Wang Q  Wu DC  Wang XW  Sun Y  Chen XY  Zhang KL  Li H 《Neuroscience letters》2004,363(3):257-261
Resveratrol induces differentiation and Fas-independent apoptosis of medulloblastoma cells by a largely unknown mechanism. CYP1A1 and 1B1 are involved in resveratrol-mediated tumor suppression but their expression in medulloblastoma cells and their relevance to anti-medulloblastoma activity of resveratrol have not been described. The statuses of CYP1A1 and 1B1 in UW228-3 medulloblastoma cells without and with resveratrol treatments were elucidated in this study with ethoxyresorufin O-deethylation assay, followed by RT-PCR, immunocytochemical staining and Western blot hybridization. CYP1A1/1B1 enzymatic activity was low in UW228-3 cells but became several folds higher upon resveratrol treatments. CYP1A1 was undetectable and CYP1B1 was expressed in normally cultured cells. Accompanied by the increased fraction of apoptosis, enhanced CYP1A1 and downregulated CYP1B1 were observed in resveratrol-treated cells in time- and dose-related fashions. Our results demonstrate for the first time that in the medulloblastoma cell system, CYP1A1 upregulation is paralleled with resveratrol-induced differentiation and apoptosis, while CYP1B1 may not be an essential element in metabolic activation of resveratrol in those cells. CYP1A1 and 1B1 are resveratrol response genes and potential chemosensitive markers of medulloblastoma cells.  相似文献   
2.
目的:评估圆锥角膜快速跨上皮交联手术前以及术后1mo Corvis ST参数的重复性及差异性。方法:研究纳入了30例30眼圆锥角膜患者进行分析。圆锥角膜患者术前和术后1mo分别进行三次Corvis ST重复测量。采用组内相关系数(ICC)、克伦巴赫alpha系数(Cronbach'α)、可重复性系数(RC)和变异系数(CV)评估Corvis ST参数的可重复性。采用配对t检验或Wilcoxon秩和检验评估术前与术后Corvis ST参数的差异。结果:术前39个Corvis ST参数中,26个(66.67%)参数重复性较好,6个(15.38%)参数重复性中等,7个(17.95%)参数的重复性较差。交联术后1mo,34个(87.18%)参数的重复性较好,3个(7.69%)参数重复性中等,2个(5.13%)参数的重复性较差。与术前相比,交联术后1mo圆锥角膜患者的眼压、生物力学校正眼压、第一次压平时间、曲率半径、第一次压平时的形变幅度、最大压陷偏离长度、角膜硬度参数值增加;而陡峭曲率、平坦曲率、平均曲率、第二次压平时间、2 mm最大形变幅度比值和综合半径值降低(均P<0.05)。结论:交联手术前和术后1mo Corvis ST参数均具有较好的可重复性,术后1mo圆锥角膜患者的角膜硬度较术前增加。  相似文献   
3.
目的:观察角膜硬度参数(SP-A1)在不同年龄以及不同严重程度分级圆锥角膜患者中的特征。

方法:横断面研究。连续纳入2018-09/2020-12在河南省立眼科医院诊断为圆锥角膜的患者247例345眼,平均年龄24.51±6.38岁。根据年龄将患者分为≤20岁组、21~30岁组和≥31岁组。采用Amsler-Krumeich(AK)分级将圆锥角膜严重程度分为AK1、AK2、AK3和AK4。测量患者视力、角膜平坦曲率(K1)、角膜陡峭曲率(K2)、角膜平均曲率(Km)、最薄点角膜厚度(TCT)。应用角膜生物力学分析仪(Corvis ST)测量患者的角膜SP-A1以及眼压、最大形变振幅(DA Max)、第1次压平时间(A1T)、第1次压平速度(A1V)、第2次压平时间(A2T)、第2次压平速度(A2V)、凹面半径(Radius)、生物力学校正眼压(bIOP)。采用Spearman秩相关分析SP-A1与其他参数的相关性。采用单因素方差分析比较不同年龄组以及不同疾病严重程度间SP-A1差异。

结果:不同年龄组间性别构成比、最佳矫正视力(LogMAR)、眼压、K1、K2、Km、TCT和严重程度分级比较差异无统计学差异(P>0.05)。圆锥角膜患者SP-A1与年龄呈弱的正相关(rs=0.137, P=0.011)。≥31岁组患者角膜SP-A1显著高于≤20岁组和21~30岁组(P<0.05)。≤20岁和21~30岁组中SP-A1与K1、K2和Km呈负相关,≥31岁组中SP-A1仅与K2呈负相关(P<0.05)。此外,总人群及各年龄组中SP-A1与DA Max、A1V和A2T呈负相关(P<0.05),与TCT、眼压、bIOP、A1T、A2V和Radius呈正相关(P<0.05)。随着疾病严重程度的增加年龄≤20岁组和21~30岁组圆锥角膜患者的SP-A1逐渐降低(P<0.05)。年龄≥31岁的圆锥角膜患者,AK1组与AK4组、AK2组与AK3组、AK2组与AK4组SP-A1的比较差异有统计学意义(P=0.008、0.035、0.001)。

结论:圆锥角膜患者SP-A1与年龄正相关,且在年龄≤30岁的患者中,SP-A1会随着疾病严重程度增加而逐渐降低。  相似文献   

4.
本研究通过回顾性分析自体外周造血干细胞移植、自体骨髓移植及二者联合移植在治疗难治性恶性淋巴瘤的疗效、毒副作用、造血和免疫功能恢复速度等临床方面的差异,总结归纳三种不同移植方式在治疗难治性淋巴瘤方面的优劣。68例难治性恶性淋巴瘤患者接受了大剂量放化疗结合自体造血干细胞移植治疗,其中10例患者为单一自体骨髓移植(autologous bone marrow transplantation,ABMT),46例患者为单一自体外周血造血干细胞移植(autologous peripheral blood hematopoietic stem cell transplantation,APBHSCT),12例患者为自体外周血造血干细胞联合自体骨髓移植(autologous peripheral blood hematopoietic stem cells transplantation combined with autologous bone marrow transplantation,APBHSCT+ABMT)。结果表明:ABMT、APBHSCT、APBHSCT+ABMT的治疗有效率和1、3、5年生存率分别为(90%和75%、57.1%、33.3%);(86.4%和74.4%、54.2%、38.1%);(83.3%和72.7%、55.6%、40%)。白细胞恢复时间分别为13天、11天、8天,血小板恢复时间分别为17天、14天、9天。在移植后3个月、6个月、1年时检测ABMT、APBHSCT、APBHSCT+ABMT患者T细胞亚群正常率分别为(0%、33.3%、60%),(10.8%、32%、73.9%),(27.3%、55.6%、85.7%)。结论:自体外周血造血干细胞联合自体骨髓移植与单一自体外周造血干细胞移植治疗难治性恶性淋巴瘤的临床疗效和毒副作用当,但联合造血干细胞移植(APBHSCT+ABMT)患者的造血功能恢复略快,有利于拓宽年龄偏大和造血功能受损患者移植方式的选择。  相似文献   
5.
目的:探讨胶质纤维酸性蛋白(GFAP)在青光眼大鼠视网膜Müler细胞上的诱导表达情况及可能的意义。方法:采用烧灼涡静脉的方法制作大鼠青光眼模型,分别于术后2h;1,3d;1,2,3wk取材,制作视网膜矢状位冰冻切片和视网膜铺片,进行GS/GFAP免疫荧光双标。提取视网膜总蛋白行GFAP免疫印迹半定量分析。结果:视网膜矢状位切片可见,正常大鼠视网膜中,GFAP阳性染色只出现在神经节细胞层的星形胶质细胞上,而Müller细胞不表达GFAP。制作青光眼模型术后2h,Müller细胞上出现GFAP阳性染色,术后1,3d,GFAP的表达显著增加,到术后1wk,GFAP在Müller细胞上的表达量达到高峰,一直持续到术后3wk,免疫印迹半定量分析与以上结果吻合。术后1wk视网膜铺片中清晰可见Müller细胞足板出现GFAP的诱导表达。结论:高眼压时GFAP在Müller细胞上的诱导表达尤其在足板处的强烈表达是Müller细胞对眼压升高产生的一种反应,GFAP可能是一种潜在的有用的生物标记物。  相似文献   
6.
OBJECTIVES: To describe prevalence and estimated attribution of human papillomavirus (HPV) types in U.S. cervical, vaginal, and vulvar precancers and cancers. METHODS: U.S. studies reporting HPV typing for cervical intraepithelial neoplasia (CIN), vulvar intraepithelial neoplasia (VIN), and vaginal intraepithelial neoplasia (VaIN) and/or invasive cancers of those sites were gathered from the PubMed database (http://www.ncbi.nlm.nih.gov/sites/entrez/). Selected studies had PCR testing data for > or =10 cases for a disease endpoint. Analytic methods augmented prior reviews of cervical disease with an updated and expanded analysis (including vulvar and vaginal disease), new selection criteria for specimens, and adjustment for histologic type, where possible, among pooled cancer cases. In addition, for analyses of estimated attribution of HPV types, we incorporated accounting methods for lesions infected with multiple HPV types. RESULTS: Data from 22 U.S. studies meeting review eligibility criteria were tabulated. Following adjustment for the presence of multiple HPV types in a single specimen, the top two HPV types contributing to disease were CIN 1 (HPV 16/66; 15.3%), CIN 2/3 (HPV 16/31; 61.9%), cervical cancer (HPV 16/18; 79.2%), VIN 1 (HPV 6/11; 41.7%), VIN 3 (HPV 16/18; 84.0%), vulvar cancer (HPV 16/33; 55.5%), VaIN 3 (HPV 16/18; 65.1%), and vaginal cancer (HPV 16/18; 72.7%). CONCLUSIONS: The HPV type distribution and proportion of cases testing positive for any HPV type were observed to vary among U.S. cervical, vulvar, and vaginal neoplasias and by grade of disease. Adjustment for the presence of multitype HPV infections can have an important effect on the estimated attribution of HPV types to disease, particularly for types other than HPV 16.  相似文献   
7.
杞菊地黄汤对化学诱导光感受器细胞凋亡大鼠的治疗观察   总被引:1,自引:0,他引:1  
目的观察不同剂量杞菊地黄汤对N甲基N亚硝脲(NmethylNnitrosourea,MNU)诱导的大鼠光感受器细胞凋亡的影响。方法SD大鼠分为正常组、模型对照组以及杞菊地黄汤6倍、3倍、1倍和1/3倍各剂量组。TUNEL法检测光感受器细胞的凋亡,常规HE染色测量视网膜外核层的厚度。结果与模型对照组相比,3倍与1倍剂量杞菊地黄汤能显著降低MNU诱导的大鼠外核层细胞凋亡百分率(P<0.01),维持外核层厚度(P<0.01);6倍和1/3倍剂量杞菊地黄汤组大鼠与模型组无差异(P>0.05)。结论3倍与1倍剂量的杞菊地黄汤对MNU诱导的光感受器细胞凋亡有抑制作用。  相似文献   
8.
Zhang KL  Ma JX  Chen XY  Sun Y  Kong QY  Liu J  Li H 《Oncology reports》2004,12(6):1335-1340
CYP1A1 expression in various tissues of 43 gastric cancer cases was analyzed with frozen tissue array-based immunohistochemical staining (IHC), RT-PCR, Western blot analysis and EROD (7-ethoxyresourfin-O-deethylase) assay. CYP1A1 was detected immunohistochemically in 86% (37/43) of gastric cancers, in both 57% (4/7) of atrophic gastritis and intestinal metaplasia and in 7.7% (1/13) of non-cancerous mucosa. RT-PCR and Western blot analysis revealed coincident results with that of IHC and ruled out possible concurrent CYP1A2 expression. EROD assay showed increased CYP1A1/1B1 activity in either cancer or premalignant tissues but not in non-cancerous ones. The frequencies of CYP1A1 expression are significantly different between non-cancerous and premalignant (P<0.025) or cancer groups (P<0.005), suggesting that CYP1A1 is expressed at relatively early stage of gastrocarcinogenesis and exerts its effects throughout the stepwise oncogenic processes.  相似文献   
9.
Ma KL  Yuan YH  Song LK  Han N  Chen NH 《Neuroscience letters》2011,491(2):148-152
The α-synuclein protein is a major component of Lewy bodies found in the brains of patients with Parkinson's disease (PD). Recently, α-synuclein 98 (α-syn98), a small isoform of the wild type protein was isolated. The neurotoxicity of this protein was assessed by over-expressing α-syn98 in dopaminergic cells. Enhanced expression of α-syn98 was insufficient to adversely affect the survival of neurons or to promote aggregation of the protein. However, when exposed to rotenone, α-syn98 over-expressing dopaminergic cells demonstrated significantly increased cytotoxicity and aggregate formation. Furthermore, we found enhanced basal ROS production and MDA levels in α-syn98 over-expressing neurons. High basal oxidative stress induced by α-syn98, combined with oxidative stress caused by rotenone treatment, promoted aggregate formation and significantly decreased cell viability. These data indicate that α-syn98 can enhance the susceptibility of dopaminergic neurons to oxidative insults by raising steady-state levels of oxidative stress.  相似文献   
10.
The constitutive androstane receptor (CAR) plays an important role in regulating the expression of detoxifying enzymes, including cytochrome P450 2B (CYP 2B). Phenobarbital (PB) induction of human CYP 2B6 and mouse CYP 2b10 has been shown to be mediated by CAR. Our previous study showed that PB-induced CYP 2B1 expression in rat primary hepatocytes is down-regulated by both n-6 and n-3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA); however, the mechanism for this down-regulation by DHA was previously unknown. The objective of the present study was to determine whether change in CAR translocation is involved in the down-regulation by n-6 and n-3 PUFAs of PB-induced CYP 2B1 expression in rat primary hepatocytes. We used 100 microM arachidonic acid, linoleic acid, eicosapentaenoic acid, and DHA to test this hypothesis. PB triggered the translocation of CAR from the cytosol into the nucleus in a dose-dependent and time-dependent manner in our hepatocyte system, and the CAR distribution in rat primary hepatocytes was significantly affected by DHA. DHA treatment decreased PB-inducible accumulation of CAR in the nuclear fraction and increased it in the cytosolic fraction in a dose-dependent manner. The down-regulation of CYP 2B1 expression by DHA occurred in a dose-dependent manner, and a similar pattern was found for the nuclear accumulation of CAR. The results of immunoprecipitation showed a CAR/RXR heterodimer bound to nuclear receptor binding site 1 (NR-1) of the PB-responsive enhancer module (PBREM) of the CYP 2B1gene. The EMSA results showed that PB-induced CAR binding to NR-1 was attenuated by DHA. Taken together, these results suggest that attenuation of CAR translocation and decreased subsequent binding to NR-1 are involved in DHA's down-regulation of PB-induced CYP 2B1 expression.  相似文献   
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