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1.
目的探讨1 470 nm激光剜除治疗高危前列腺增生的手术技巧及临床效果。 方法回顾分析2018年6月至2018年9月中山大学附属第三医院泌尿外科采用1 470 nm激光治疗共89例高危前列腺增生患者的临床资料,年龄平均(68±3)岁,前列腺体积(57.4±2.6)ml。所有患者均采用"寻找层面,先易后难,剜切结合"的层面递进法思路行激光腔内前列腺剜除术,比较患者术中及术后情况。 结果89例均顺利完成手术,与术前相比,术后3个月患者最大尿流率明显增加,[(6.9±2.1) ml/s vs(19.8±3.6) ml/s]。国际前列腺症状评分显著好转,[(24.6±1.7) vs(8.0±1.2)]。术中无输血、无电切综合征、无直肠和膀胱穿孔病例,无输尿管损伤、大出血、心脑血管意外等严重并发症发生。 结论层面递进法激光剜除技术构想对于高危前列腺增生外科包膜层面的寻找、减少术后并发症有独到优势,且易于掌握,或可为业界同行提供一个新的思路。  相似文献   
2.
Idiotypic characterization of antibody-induced antibody responses   总被引:4,自引:0,他引:4  
Anti-idiotypic antisera were produced in syngeneic (C57BL/6) mice against a monoclonal anti-Dextran B512 (Dex) antibody (38-13). In radioimmunoassays, anti-idiotypic antibodies were shown to react with the homologous idiotype, while failing to recognize another monoclonal anti-Dex antibody, independently derived from C57BL/6 mice (D-16). Plaque inhibition tests confirmed the specificity of the anti-idiotypic antibodies and revealed that the 38-13 idiotype is expressed by about half of all anti-Dex antibodies produced in C57BL/6, but not in CBA mice. Injection of normal (but not athymic) C57BL/6 mice with low doses of 38-13 monoclonal antibodies, contained culture supernatants or ascitic fluids, resulted in a 10-20 fold increase in the numbers of anti-Dex PFC detected in the spleen 5 days later, the majority of which carried the 38-13 idiotype.  相似文献   
3.
Cell membrane proteins encoded for by the major histocompatibility complex (MHC)1 are associated with the antigenic determinant(s) recognized on trinitrophenyl (TNP)-modified cells by syngeneic murine cytotoxic T lymphocytes and by hapten-reactive guinea pig T cells. To investigate the relationship of the TNP moiety on TNP-modified cells to these major histocompatibility antigens, peritoneal exudate cells or splenocytes from two inbred guinea pig strains and one inbred murine strain were TNP-modified, radioiodinated and lysed in detergent. TNP-derivatized proteins were then isolated using an anti-TNP immunoabsorbent, and the presence on TNP-derivatized histocompatibility antigens in the eluted proteins was determined by immunoprecipitation experiments and SDS-polyacrylamide gel electrophoretic analysis. Whereas most of the various histocompatibility antigens examined were found to be TNP-derivatized in amounts proportional to the degree of membrane protein derivation as a whole, only small amounts of TNP-modified strain 2 guinea pig Ia antigens were found, and no hapten-modified strain 13 guinea pig Ia antigens were detected. It is concluded that, in contrast to most MHC gene products, strain 13 Ia antigens are not derivatized on TNP-modified cells and, thus, represent an important exception demonstrating that histocompatibility antigens need not be directly TNP-derivatized for T cell recognition and activation.  相似文献   
4.
A sensitive and reproducible enzyme-linked immunosorbent assay (ELISA) has been developed using T cell hybridomas as coating antigen, for detection of Fc receptors for IgA (Fc alpha R). T-T hybridomas were generated from fusions of Fc alpha R+ T cell clones from mouse Peyer's patches with the Fc alpha R- R1.1 T lymphoma cell line. The 2 T-T hybridomas (designated Th HA) used here express Fc alpha R as determined by a rosette method and by ELISA. Th HA cells were cultured under conditions for maximum Fc alpha R expression, were added to individual wells of 96-well EIA plates, and were fixed in situ with glutaraldehyde. Plates were incubated with purified mouse monoclonal IgA, IgM or IgG1 and were developed with beta-galactosidase-coupled goat IgG antibodies specific for mouse heavy chains. Using the ELISA, both Th HA cell lines were shown to express significant levels of Fc alpha R, lower but detectable Fc mu R, and no discernible Fc gamma 1R. Interestingly, the rosette assay only allowed detection of receptors for IgA. When splenic lymphocytes were used, good Fc mu R and less Fc alpha R expression occurred on these cells as determined by ELISA and rosetting; however, no Fc gamma 1R cells were detected by either method. Thus, the ELISA is sensitive and reproducible, and allows an objective measurement of FcR expressed on T cells.  相似文献   
5.
目的 了解职业技术类院校护理及助产专业医学生的心理对其医患沟通技能的影响作用,为职业技术类院校的医学生医患沟通技能提升提供指导。 方法 利用成熟的医学生医患沟通态度、技能以及心理学相关量表设计调查问卷,采用全部抽样的方式,对忻州职业技术学院护理专业学生进行调研,并最终获得264份有效问卷用于逐步进入法的多元线性回归分析。 结果 分析结果表明,医学生学习医患沟通技能的积极态度(r=0.39,P<0.001)、情绪疏泄能力(r=0.29,P<0.001)、观点采择意识(r=0.20,P<0.001)对其医患沟通技能水平的作用具有统计学意义。 结论 职业技术类院校在培养医学生的医患沟通技能时,应重点关注学生的积极学习态度、情绪疏泄能力和观点采择意识。  相似文献   
6.
目的 通过已建立的小鼠睾丸体外培养系统,研究四种内分泌干扰物(Endocrine Disrupting Chemicals,EDCs)对男性内分泌系统的影响。 方法 将新生小鼠的睾丸组织在体外环境中培养24h,而后在培养基中分别加入浓度为0.1μM, 1μM, 10μM and 100μM的四种(DEHP、MEHP、NP、p, p’-DDE)内分泌干扰物并培养72h,同时设置对照组;培养结束后进行组织学观察,测定冻存培养基中睾酮和抑制素βB (INH-βB)的分泌水平,同时测定细胞色素P450侧链裂解酶(P450Scc)、3β-羟基类固醇脱氢酶(3β-HSD)、细胞色素P45017α-羟化酶(P450C17)和波形蛋白(vimentin)的基因表达情况。 结果 所有剂量组中睾酮的分泌水平均发生改变;P450Scc、3β-HSD、P450C17和INH-βB蛋白质的表达及mRNA水平均受到四种内分泌干扰物的影响(P<0.05);DEHP和MEHP降低了波形蛋白的mRNA水平(P<0.05),而NP和p, p’-DDE对波形蛋白没有显著影响(P>0.05)。 结论 本研究建立的体外培养新生小鼠睾丸模型中,所选的四种已知EDCs改变了两种睾丸激素水平,三种类固醇合成酶以及与支持细胞功能相关的波形蛋白的表达。  相似文献   
7.
目的 建立啤酒中4种N-亚硝胺类化合物(N-亚硝基二甲胺、N-亚硝基二乙胺、N-亚硝基二丙胺、N-亚硝基二苯胺)的同位素稀释固相萃取-气相色谱串联质谱测定方法。 方法 样品经活性炭固相萃取小柱富集、二氯甲烷洗脱,洗脱液经氮吹浓缩定容后,采用INNOWAX毛细管色谱柱分离,多反应监测(MRM)模式检测,同位素稀释内标法定量。 结果 各物质在5 μg/L~200 μg/L范围内线性关系良好,相关系数均大于0.9995。方法的检出限为0.03-0.10 μg/L,定量限为0.10~0.33 μg/L。不同水平的加标回收率为72.1%~100.3%,相对标准偏差为1.5%~9.5%(n=6)。 结论 该方法操作简单,灵敏度和准确度高,适用于啤酒中4种N-亚硝胺类化合物的测定。  相似文献   
8.
目的 了解云南省中-缅、中-老、中-越跨境婚姻家庭艾滋病、梅毒和乙肝检测情况,为完善跨境婚姻家庭预防母婴传播相关服务政策提供科学依据。 方法 对目前居住在云南省边境地区的中国籍和跨境婚姻家庭进行调查和访谈,收集一般人口学特征、最近一次怀孕期间三病检测情况等信息。经整理后,使用构成比和率对指标进行计算,使用卡方检验、秩和检验比较中国籍和跨境婚姻家庭各项检测服务状况。 结果 外籍媳妇主要以农民、文盲/小学、无经济收入的少数民族为主。配偶检测率,老挝籍低于当地中国籍媳妇(〖XC五号.EPS;P〗=7.87,P=0.005),缅甸籍、越南籍与当地中国籍没有差异;缅甸籍高于老挝籍和越南籍(〖XC五号.EPS;P〗=41.84,P<0.001)。三病检测点知晓率,缅甸籍媳妇低于当地中国籍媳妇(〖XC五号.EPS;P〗=6.11,P<0.03),越南籍、老挝籍与当地中国籍没有差异;老挝籍高于缅甸籍和越南籍(〖XC五号.EPS;P〗=44.03,P<0.001)。获得预防母婴传播相关知识比例,三个外籍媳妇均低于当地中国籍(〖XC五号.EPS;P〗=19.84,P<0.001;〖XC五号.EPS;P〗=7.52,P=0.006;〖XC五号.EPS;P〗=4.38,P=0.036)。 结论 边境地区针对跨境婚姻家庭开展艾滋病、梅毒和乙肝预防母婴传播相关工作取得实效,三病检测情况与当地中国籍基本一致,但在其他服务利用上仍存在一定差距,外籍媳妇孕早期三病检测率及其配偶检测率、相关预防母婴传播知识获取还有待提升,需要运用更加有效的服务管理模式来促进三病检测可及性的进一步提高。  相似文献   
9.
目的:观察TNP-470对人恶性胶质瘤细胞系SHG-44体内和体外生长的影响。方法:采用MTT法、软琼脂克隆法、流式细胞仪、光镜和透射电镜技术观察SHG-44细胞体内外增殖、克隆形成、细胞周期和形态学变化及异种移植瘤生长情况。结果:20-2000ng/mlTNP-470可显著抑制SHG-44细胞体外增殖,克隆形成率显著降低,G0/G1期细胞明显增多,S、G2/M期细胞减少。彩和30mg/kg体重TNP-470隔日皮下注射后,移植瘤体积缩小、重量显著减轻,组织出现明显调亡细胞和坏死。结论:TNP-470对SHG-44细胞的生长抑制作用与其调控细胞周期和诱导细胞凋亡相关,提示TNP-470作为一种血管生成抑制剂对胶质瘤细胞生长也具有直接抑制作用。  相似文献   
10.
Conclusion The molecules described herein as antiangiogenic agents and antimetastatic agents represent a wide variety of molecular structures with a wide variety of biological effects and targets. Most often these agents have been generally classified as antiangiogenic or antimetastatic by their effects in an in vitro bio-assay system. The diversity in this group of molecules gives strength to the potential of this approach in therapeutic applications. The biological and biochemical pathways involved in angiogenesis are numerous and redundant. It is likely that there are many angiogenic factors and many pathways of invasion, therefore it is likely that blockade of more than one pathway related to angiogenesis and/or invasion will be necessary to impact on the natural progress of a malignant disease.The vasculature forms the first barrier to penetration of molecules into tumors. Although the antiangiogenic agent treatments administered in this study did not inhibit angiogenesis in these tumors completely, the vasculature present in the treated tumors may be impaired compared to control tumors. Overall, therefore, the best speculation is that the main targets for the antiangiogenic agents are extracellular matrix processes and/or tumor endothelial cells and that inhibition and/or impairment of these non-malignant functions can improve therapeutic responses when used in combination with cytotoxic therapies. The incorporation of antiangiogenic agents and/or antimetastatic agents into therapeutic regimens represents an important challenge. The successful treatment of cancer requires the eradication of all malignant cells and therefore treatment with cytotoxic therapies. The compatibility of antiangiogenic therapy and/or anti-invasion agents with cytotoxic chemotherapeutic agents is not obvious [316].The goal of the addition of any non-cytotoxic potentiator to a therapeutic regimen is to take a good therapy and, without additional toxicity, push it to cure.Cyclophosphamide is a good drug against the Lewis lung carcinoma although no long-term survivors of animals bearing Lewis lung carcinoma are achieved with cyclophosphamide treatment alone. Adding antiangiogenic agents to treatment of this tumor with cyclophosphamide produced a cure rate of 40–50%, meaning that both the primary and metastatic disease has been eradicated in these animals. Cures were achieved only when the antiangiogenic treatments extended from days 4–18 post Lewis lung tumor implantation. The results obtained with the addition of antiangiogenic agents to cytotoxic anticancer therapies in in vivo models of established solid tumors have been very positive and provide direction for future clinical trials including these antiangiogenic agents. Two conclusions may be drawn. First, combinations of antiangiogenic and/or antimetastatic agents evoke a greater effect on tumor response to therapy than does treatment with single agents of these classes. Second, treatment with antiangiogenic agents and/or antimetastatic agents can interact in a positive way with cytotoxic therapies.  相似文献   
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