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1.
Background Renal transplantation in sensitized candidates remains a highly significant challenge worldwide. The production of panel reactive antibody (PRA) against human leukocyte antigen (HLA) is a major risk factor in presensitized recipients. The aim of this study was to evaluate the impact of HLA matching and recipients' PRA on two-year outcome in presensitized renal allograft recipients.
Methods We determined the percentage of panel reactivity and specificity of anti-HLA immunoglobulin (Ig) G antibodies in 73 presensitized renal allograft recipients compared with 81 unsensitized recipients (control group). HLA genotyping of both recipients and corresponding donors was performed by PCR with sequence-specific primers (PCR-SSP). We analyzed the factors influencing the early graft outcome (two-year rejection rates and survival rates of the grafts), including HLA mismatching, class and degree of panel reactivity, and target antigen of donors.
Results Presensitized recipients had a worse two-year outcome than unsensitized recipients (P=0.019 for rejection rate, P=0.01 for survival rate). The difference in number of HLA-mismatched alleles with either 6-antigen matching (Ag M) standard or amino acid residue matching (Res M) standard was not significant between the rejection and non-rejection groups of presensitized recipients or between the graft survival group and graft loss group. Compared with the control group, recipients with both PRA-I and PRA-II antibodies had a significantly worse two-year outcome (P=0.001 for rejection rate, P=0.002 for survival rate). The two-year outcomes of the peak PRA 〉50% group and its subgroup, at-transplant PRA 〉50% group, were significantly worse compared with the control group (P=0.025 and P=0.001 for rejection rate, P=0.043 and P=0.024 for survival rate). The rejection rates of the at-transplant target antigen positive group and its subgroup, HLA-I target antigen positive group, were significantly higher than the control group (P=0.001 and P=-0.001), target antigen negative group (P=0.003 and P=0.001), and peak target antigen positive with negative at-transplant target antigen group (P=0.024 and ,0=-0.002). Two-year graft survival rates of the target antigen positive group and HLA-I target antigen positive group were significantly lower than the control group (P=0.012 and ,P=0.001). The two-year outcome of target antigen unknown group was similar to that of the target antigen positive group. Presensitized recipients with pre-transplant plasmapheresis or immunoadsorption (PRA prepared group) had a better but non-significant two-year outcome than the control group. However, the PRA unprepared presensitized recipients were different to the control group (P=-0.004 for rejection rate and P=-0.005 for survival rate). Hyperacute rejection (HR) occurred in three recipients with positive HLA-I target antigen and without mismatch according to Res M and in one case with positive PRA-II (for an unknown target antigen). No HR occurred in eight cases with positive HLA-II target antigens.
Conclusions Pre-transplant PRA preparations might improve the access of presensitized patients to renal donors. Avoiding antigen-positive donors remains a fundamental measure in preventing HR and early rejections.  相似文献
2.
目的探讨生存素反义寡核苷酸(生存素-ASODN)对化疗药多西紫杉醇(泰索帝)诱导膀胱癌细胞系BIU87细胞凋亡的影响。方法将已构建成功的生存素-ASODN真核表达载体pcDNA3-SWas通过脂质体介导转染膀胱癌细胞系BIU87,并筛选转染成功的阳性克隆;采用逆转录聚合酶链反应(RT-PCR)法检测其生存素mRNA表达;锥虫蓝拒染法观察生存素-ASODN与泰索帝联合应用对BIU87细胞生存的影响;细胞计数和四甲基偶氮唑盐(MTT)试验测定转染细胞对泰索帝敏感性;琼脂糖凝胶电泳分析细胞凋亡DNA断裂情况;核染色检测凋亡细胞的细胞核的变化;流式细胞术检测细胞凋亡率。结果转染生存素-ASODN真核表达载体pcDNA3-SWas的BIU87-SVVas细胞生存素mRNA表达水平下降、细胞增殖明显受抑,与转染pcDNA3空载体BIU87-neo细胞、未转染载体的BIU87细胞进行比较,差异均有统计学意义(均P〈0.05);经琼脂糖凝胶电泳,BIU87-SVVa8细胞可见到DNA梯形条带,而其他对照组未见到;与BIU87-neo、BIU87细胞相比,BIU87-SVVas细胞的细胞核呈致密浓染;加入泰索帝的BIU87-SVVas细胞组的凋亡率大幅度增加。结论生存素-ASODN可促进泰索帝诱导BIUg7细胞凋亡及增加其对泰索帝的敏感性,为膀胱癌的生物学治疗研究奠定了实验基础。  相似文献
3.
Background Dysregulation of apoptosis has been implicated not only in carcinogenesis and tumor progression but also in tumor recurrence. We investigated whether the expression of X-linked inhibitor of apoptosis (XIAP) might predict early recurrence in patients with non-muscular invasive bladder cancer. Methods The cohort comprised 176 consecutive patients with primary superficial bladder cancer treated with transurethral resection. Immunohistochemical staining using the standard avidin-bioUn-peroxidase technique and RT-PCR were used to detect XIAP protein and mRNA expressions in cancer tissues. The relationship between XIAP expression and clinicopathological characteristics, cancer recurrence were analyzed. Results XIAP expression was observed in 108 cases (61.4%) and no expression in 68. There was no correlation between XIAP expression rate and the tumor pathological grade, but was an apparent trend toward the increased XIAP levels from well (G1) to poor (G3) differentiated cancer. Eighty-two (46.6%) patients experienced tumor recurrence at a mean of 28.6 months of the follow-up; 66 of them expressed XIAP (61.1%) and 16 were XIAP negative (23.5%). Twelve patients presented with invasive disease at the time of relapse and all of them expressed XIAP. Patients without XIAP expression or with low tumor grades had significantly higher recurrence-free survival than those with XIAP expression (log rank test ,P=-0.0015) or high tumor grades (log rank test P〈0.001). Multivariate analysis revealed that XIAP expression, tumor grade, and tumor number were independent predictors for the recurrence of non-muscular invasive bladder cancer (P=-0.004, 0.016, and 0.043, respectively). Conclusions XIAP may be considered as a new independent prognostic marker for early recurrence of non-muscular invasive bladder cancer.  相似文献
4.
目的尝试应用经脐单孔多通道腹腔镜技术切除猪肾,总结基本操作技巧,提高手术熟练程度,降低临床实践风险。方法采用Triport单孔系统完成10例次(5只)经腹单纯猪肾切除,总结手术操作经验,包括术中对Port的安置、左右手器械的选配、内镜的选择、基本操作手法的优化等,观察手术操作水平的变化。结果10例次手术均顺利完成,未另外增加工作通道,无周围脏器损伤等并发症发生;肾切除时间从75min缩短至23min。器械干扰是单孔腹腔镜肾切除术的难点,器械X型交叉可部分解决此问题,据此设计的4种基本操作模式避免器械干扰。结论单孔腹腔镜猪肾切除操作有助于初学者提高手术熟练程度,掌握手术技巧,缩短学习曲线,有利于降低临床实践风险。  相似文献
5.
It has been suggested that progression of bladder transitional cell cancer (BTCC) may be regulated at the molecular level by a typical pattern of expression of genes involved in apoptosis. Re-cently Livin, belonging to the inhibitors of apoptosis (IAP) family, has been found to be expressed in most solid tumors, where its expression is suggested to have clinical significance. In order to explore the significance of Livin expression in the development of BTCC, immunohistochemistry and RT-QPCR were used to detect the expression of Livin mRNA in tumor tissues and adjacent normal tissues of 30 cases of BTCC. The results showed that the positive rate of Livin expression in adjacent normal tissues and tumor tissues was 0 and 60% (18/30) respectively. The -△△CT value of Livin in BTCC tissues was 8.0454 (7.4264-8.6644) times of that in adjacent normal tissues. The expression of Livin mRNA had no correlation with tumor pathological grades and clinical stages. It was sug-gested that there was weak expression of Livin mRNA in adjacent normal tissues, but strong in tumor tissues.  相似文献
6.
目的初步尝试机器人单孔腹腔镜下行猪肾部分切除术及肾盂输尿管成形术,评估机器人单孔腹腔镜下行泌尿外科重建手术的可行性和不同通道技术的人机工程学效果,总结操作经验。方法猪肾部分切除术:完全侧卧位,平脐水平,沿腹直肌外缘切开4 cm长皮肤切口,钝性分离皮下脂肪,以气腹针建立气腹。按菱形将4个套管置入腹腔,其中左右为8mm的达芬奇机器人金属套管,上下为Surgiquest 10 mm无阀套管。安装机器人臂后,按常规完成肾部分切除术,肾脏缺损采用"滑夹"的无结技术进行全层水平褥式缝合关闭。肾盂输尿管成形术(UPJ):改用Surgiquest新型无阀单孔通道,切口两侧置入8 mm的机器人金属套管。观察镜接12 mm普通腹腔镜套管后,置入单孔通道内,按常规完成UPJ成形术。结果完成肾部分切除术2例,通道建立时间分别为5、8 min,机器人系统安装时间为11、9 min,手术操作时间为55、42 min,温缺血时间23、18min,出血50、20 ml。完成肾盂输尿管成形术2例,通道建立时间为17、12 min,机器人安装时间为5、4 min,手术操作时间为32、25 min,出血均为0 ml。结论机器人单孔腹腔镜手术在合理安置通道后,能顺利完成泌尿外科高难度重建手术;专用机器人单孔通道可获得更理想的人机工程学效果。  相似文献
7.
目的尝试单孔腹腔镜下经膀胱根治性切除猪前列腺,探讨其可行性,总结操作难点,为后续临床应用奠定基础。方法采用雄性未阉割香猪,全麻下进行膀胱外翻皮肤造口;将TriPort单孔多通道系统经造口处置入膀胱并固定;建立气膀胱后,用传统腹腔镜器械模拟人经膀胱前列腺根治性切除术;经膀胱完成膀胱内口与尿道吻合,经皮肤造口取出前列腺标本后关闭膀胱和腹腔。结果共完成了6例动物实验,前3例失败,原因为膀胱操作空间无法保证、吻合操作失败等;后3例均顺利完成,手术时间分别是190、160、110min,前列腺完整切除,间断吻合6针恢复尿道连续性。结论单孔腹腔镜下经膀胱猪前列腺根治性切除技术可行,但操作难度较大,鉴于猪解剖结构与人存在较大差异,需进一步在尸体模型上进行类似尝试,目前尚不适合向临床阶段过渡。  相似文献
8.
大鼠肾移植三种尿路重建术式的比较   总被引:8,自引:1,他引:7  
目的 对大鼠肾移植3种尿路重建术式进行比较,筛选出稳定性好、并发症少的手术方案.方法 以3种术式进行大鼠同系肾移植尿路重建:A组,供/受体输尿管端端吻合术(n=14);B组,供体膀胱瓣-受体膀胱吻合术(n=15);C组,供体输尿管-受体膀胱浆肌层隧道术(n=17).对各组尿路重建时间、尿路并发症以及血肌酐动态指标进行比较.结果 A、B、C 3组手术时间分别为(6±2.0)min、(14±2.5)min、(7±2.0)min, A组与C组差异无统计学意义, B组用时分别与A组、C组差异有统计学意义(P<0.05);术后,A组输尿管梗阻发生率最高(21.4%),B组尿漏发生率最高(13.3%);C组术后尿路并发症总发生率最低,为11.8%,A、B两组术后尿路并发症总发生率分别为28.5%和26.1%,与C组之间差异均有统计学意义(P<0.05);血肌酐监测显示A组术后40d与C组差异有统计学意义(P<0.05),术后60d与B、C两组间差异有统计学意义(P<0.05).结论 供体输尿管-受体膀胱浆肌层隧道吻合术后尿路并发症少,对移植肾恢复影响小,是大鼠肾移植尿路重建的较理想方案.  相似文献
9.
后腹腔镜肾癌根治术67例报告   总被引:7,自引:2,他引:5  
目的:探讨后腹腔镜肾癌根治术的手术经验和临床效果. 方法:2006年1月至2007年12月,后腹腔镜肾癌根治术67例.男44例,女23例.年龄23-80岁,平均52岁.肿瘤位于右侧35例,左侧32例;位于肾上极15例,中极29例,下极23例.肿瘤直径1.5~8.0 cm,平均4.64 cm.术前肿瘤分期:T1N0M0 64例,T2N0M0 3例.结果:手术时间为55~253 min,平均110 min.术中出血10~500ml,平均98ml,前10例平均出血152ml,后10例平均出血量仅58ml.术后住院7~12d,平均8d.术后肠功能恢复时间1~2 d.术后随访2~26个月,平均12.1个月.无局部复发或远处转移,无切口或操作孔肿瘤种植. 结论:后腹腔镜肾癌根治术具有微创、出血少、术后恢复快等优点,是一种安全、可靠的手术方法.  相似文献
10.
阳虚体质者内分泌及免疫功能变化   总被引:7,自引:0,他引:7  
观察阳虚体质者内分泌功能和环核苷酸系统及免疫功能的变化,探索阳虚质特征、成因与生理生化指标的关联性。方法:在临床流行病学调查的基础上,按阳虚质和平和质的诊断标准筛选阳虚质60例和平和质50例,清晨8:00~9:00空腹抽取静脉血8ml,3000r/min离心5min分离血清,-70℃冰箱中保存,采用酶联免疫吸附检测(enzyme—linked immunosorbent assay,ELISA)法测定阳虚质及平和质血清皮质酮、皮质醇、促肾上腺皮质激素(adrenocorticotrophic hormone,ACTH)、环腺苷酸(cyclic adenosine monophosphate,cAMP)、环乌苷酸(cyclic guanosine monophosphate,cGMP)、游离三碘甲状腺原氨酸(free triiodothyronine,FT3)、游离甲状腺素(free thyroxine,FT4)、促甲状腺素(thyrotropic—stimulating hormone,TSH)、白细胞介素1β(interleukin-1β,IL-1β)和白细胞介素2(interleukin-2,IL-2)水平,计算cAMP/cGMP比值,并对阳虚质与平和质上述指标之间的差异进行分析。结果:与平和质比较,阳虚质血清皮质酮、cAMP/cGMP比值、IL-1β和TSH含量较高,而血清皮质醇、ACTH、cGMP及FT。含量则较低。结论:阳虚质与下丘脑-垂体肾上腺轴、下丘脑-垂体甲状腺轴功能减退,及环核苷酸系统和免疫功能紊乱具有一定的关联性。  相似文献
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