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81.
目的 观察成人胰岛细胞及肾联合移植治疗胰岛素依赖型糖尿病合并尿毒症的临床效果。方法 对 4例胰岛素依赖型糖尿病合并尿毒症的患者施行成人胰岛细胞及肾联合移植。肾移植为常规术式 ,在移植肾开放血液循环后 ,将分离、纯化、培养好的胰岛细胞注入门静脉中。移植后监测患者的空腹血糖、基础C 酞、糖化血红蛋白及肾功能的变化 ,并与其术前各项指标比较。结果  4例患者术后在观察期间内胰岛素的用量均较术前减少超过 2 5 % ,且持续 3个月以上 ;空腹血糖基本保持在正常水平 ,基础C 酞也基本维持在正常水平 ,糖化血红蛋白于术后降至正常水平 ;4例患者的移植肾功能良好 ,3例患者已恢复正常工作。结论 成人尸体胰岛细胞及肾联合移植治疗胰岛素依赖型糖尿病合并尿毒症的临床效果较好 ,具有操作简单、安全等优点  相似文献   
82.
Radiocontrast-induced nephropathy (RCIN) is a common cause of hospital-acquired acute renal failure and is associated with a high mortality rate. RCIN is potentially preventable, because administration of the radiocontrast agent is predictable, and a high-risk population has been identified. This multicenter, prospective, randomized, double-blind, placebo-controlled trial was performed to evaluate the efficacy of intravenous atrial natriuretic peptide (anaritide, ANP 4-28) to prevent RCIN. Patients with stable chronic renal failure (serum creatinine greater than 1.8 mg/dL or serum creatinine between 1.5 and 1.8 mg/dL with estimated creatinine clearance of < or = 65 mL/min) were assigned to receive either placebo or one of three doses of anaritide (0.01 microg/kg/min, 0.05 microg/kg/min, or 0.1 microg/kg/min) for 30 minutes before and continuing for 30 minutes after radiocontrast administration. All patients were given intravenous 0.45% saline for 12 hours before the radiocontrast procedure and continuing for 12 hours after the last dose of radiocontrast. Both ionic and nonionic radiocontrast agents were administered. RCIN was defined as either an absolute increase of serum creatinine of > or = 0.5 mg/dL or a percent increase of > or = 25% over baseline. Of the 247 patients who completed the study, 50% had diabetes mellitus. There were no statistical differences in baseline serum creatinine, change in serum creatinine, or the incidence of RCIN. The incidence of RCIN was placebo, 19%; anaritide (0.01), 23%; anaritide (0.05), 23%; anaritide (0.1), 25%. Patients with diabetes mellitus had a significantly greater incidence of RCIN: placebo, 26% versus 9%; anaritide (0.01), 33% versus 13%; anaritide (0.05), 26% versus 21%; anaritide (0.1), 39% versus 8% (diabetic v nondiabetic, P < 0.002). There was no effect in the diabetic or nondiabetic groups by anaritide on the incidence of RCIN. Comparison of the highest-risk group of patients, defined as patients with diabetes mellitus and a baseline serum creatinine > or = 1.8 mg/dL, with the lowest-risk group, defined as patients without diabetes mellitus and a baseline serum creatinine of 1.8 mg/dL or less, did not show a beneficial effect of anaritide administration. In conclusion, administration of intravenous anaritide before and during a radiocontrast study did not reduce the incidence of RCIN in patients with preexisting chronic renal failure, with or without diabetes mellitus.  相似文献   
83.
84.
目的 探讨IgA肾病的病理特点,提高诊断合格率.方法 回顾性分析3例有血尿症状的IgA肾病患者被误诊为尿路感染血尿的经过和原因.结果 3例患者均为系膜增生性IgA肾病患者,HaasⅠ级2例、HaasⅡ级1例,均于发病前出现过尿路感染,确诊后均已治愈.结论 IgA肾病的复杂性和隐匿性使其易被误诊,临床诊断要全面掌握IgA肾病的临床与病理特点,不能局限于表面症状的诊断.  相似文献   
85.
目的:探讨Cadherin-Catenin复合体在胃癌癌变过程中的表达及生物学意义。方法:建立组织芯片技术平台,应用该技术和免疫组化sp法检测2种蛋白在胃癌石蜡标本中的表达。结果:126例标本的组织芯片制备成功。其中E-cad在4组中的阳性率分别为86.7%,80.7%,55%和53.8%,胃癌组与正常胃和胃炎组比较有统计学意义(P<0.05和P<0.05)。而β-cat的阳性率分别为93.3%,57.7%,55%和49.2%,其中胃癌组,胃上皮非典型增生,胃炎组与正常组比较均有统计学意义(P<0.01,P<0.05和P<0.05)。两种蛋白的表达与胃癌的组织分化和淋巴结转移显著相关,但与年龄、临床分期等无明显相关。结论:建立了组织芯片技术平台,本研究中E-cad、β-cat的表达下调指示二者与胃癌发生密切相关,且均与胃癌组织分化和淋巴结转移密切相关,联合检测E-cad、β-cat可作为预测胃癌发生和发展的肿瘤标志物。  相似文献   
86.
Rhee  BG; Hall  ER; McIntire  LV 《Blood》1986,67(1):240-246
A cone and plate viscometer and Coulter Counter were used to study platelet modulation of polymorphonuclear leukocyte (PMNL) aggregation caused by controlled shear stress. As an index of aggregation, the large-particle percentage (LPP) was calculated. This represents the ratio of aggregated cell count to total cell count. PMNL suspensions in buffer (1.0 X 10(7) cells per milliliter, final concentration) did not show any aggregate formation at shear stresses below 150 dynes/cm2 for one minute exposure time (LPP less than 3%). However, there was PMNL aggregation in mixed PMNL and platelet-rich plasma suspensions in this shear stress range. Supernatant plasma from sheared platelets initiated PMNL aggregation at moderate shear stress (150 dynes/cm2 for one minute; LPP, 20.3% +/- 2.5%). In contrast, platelet release factors, such as adenosine diphosphate (2 mumol/L) and serotonin (2 mumol/L) did not cause PMNL aggregation (LPP, 2.9% +/- 1.2% and 3.3% +/- 0.8%, respectively). The use of a cyclo-oxygenase inhibitor (acetylsalicylic acid, 50 mumol/L) did not suppress the aggregation of PMNLs after shear (LPP, 20.1% +/- 2.4%). However, preincubation with nordihydroguaiaretic acid (10 mumol/L), an inhibitor of C-5 and C-12 lipoxygenase, and 6,9- deepoxy-6,9-(phenylimino)-6,8-prostaglandin I1 (U-60257, 10 mumol/L), an inhibitor of C-5 lipoxygenase in human leukocytes, suppressed this aggregation (LPP, 9.1% +/- 2.5% and 10.4% +/- 3.2%, respectively). Also, the formation of lipoxygenase products (5-HETE, 12-HETE, 15-HETE, and LTB4) activated by shear stress was documented by reversed phase- high-performance liquid chromatography (RP-HPLC). These data support the possibility of a cooperation between platelets and leukocytes in shear-induced PMNL aggregation that is dependent on C-12 or C-5 lipoxygenase activity, or both.  相似文献   
87.
目的探讨绝经前后女性冠心病患者高密度脂蛋白(HDL)颗粒及低密度脂蛋白(LDL)颗粒与冠状动脉病变程度的关系。方法收集经冠状动脉造影确诊的女性冠心病患者79例,根据是否绝经分为绝经前组(n=37)和绝经后组(n=42)。Lipoprint脂蛋白分析仪对HDL颗粒及LDL颗粒进行检测分析,探讨两种脂蛋白颗粒与冠状动脉病变程度的关系。结果与绝经前组比较,绝经后组大颗粒HDL浓度(102.6±45.2 mg/L比143.8±49.7 mg/L,P0.05)及所占比例(23.34%±8.26%比31.15%±7.98%,P0.05)、LDL颗粒平均直径(259.5±8.1比265.7±3.7,P0.05)均降低,小颗粒HDL浓度(124.0±76.8 mg/L比87.0±34.9 mg/L,P0.05)及所占比例(27.26%±12.34%比18.62%±6.53%,P0.05)、LDL B型比例(73.8%比48.6%,P0.05)、Gensini积分(50.88±26.46比30.43±18.54,P0.05)均增高。绝经前组及绝经后组多支病变患者大颗粒HDL浓度、LDL颗粒平均直径均低于单支病变患者,Gensini积分高于单支病变患者;绝经后组大颗粒HDL浓度、LDL颗粒平均直径均低于绝经前组,小颗粒HDL所占比例及Gensini积分高于绝经前组。绝经前组和绝经后组LDL颗粒大小及大颗粒HDL浓度均与Gensini积分呈负相关。结论与绝经前组相比,绝经后组大颗粒HDL浓度较低,小颗粒HDL浓度较高,LDL颗粒平均直径较小,冠状动脉病变程度较严重;大颗粒HDL浓度及LDL平均直径与冠状动脉病变严重程度明显相关。  相似文献   
88.
Lithium augments GM-CSA generation in canine cyclic hematopoiesis   总被引:1,自引:0,他引:1  
Hammond  WP; Rodger  ER; Dale  DC 《Blood》1987,69(1):117-123
Cyclic hematopoiesis in gray collie dogs can be cured by lithium treatment. We examined the mechanism of lithium's effect by developing an assay for the canine equivalent of GM-CSF (called GM-CSA). Phytohemagglutinin (PHA)-stimulated canine blood mononuclear cells produce GM-CSA in a dose-dependent manner; this GM-CSA stimulates more neutrophil-containing colonies than does endotoxin-treated dog serum. Production of GM-CSA by PHA-stimulated normal dog cells was not altered by lithium. However, cells from gray collies during their neutrophilic period increased their GM-CSA when lithium (2 mEq/L) was added to low doses of PHA, whereas neutropenic gray collie cells did not. These data suggest that lithium could modulate cyclic hematopoiesis by increasing intramedullary GM-CSA at the time when marrow neutrophilic progenitor cells are at their nadir.  相似文献   
89.
Bang  A; Speck  ER; Blanchette  VS; Freedman  J; Semple  JW 《Blood》1996,88(8):2959-2966
Leukoreduced allogeneic platelet transfusions have been previously shown to initially stimulate an in vitro cellular cytotoxicity and subsequently Induce the formation of immunoglobulin G (IgG) antidonor alloantibodies. To further characterize these responses and determine if they are related, recipient BALB/c H-2d mice were treated with aminoguanidine (AMG), a selective inhibitor of inducible nitric oxide synthase (iNOS), and transfused weekly with 2 x 10(8) C57BL/6 H2b platelets. In control, non-AMG-treated mice, transfusion significantly (P < .01) increased serum levels of interferon-gamma (IFN-gamma) by day 1 posttransfusion (PT). IFN-gamma returned to pretransfusion levels by day 3 PT, and its production was not affected by AMG treatment. Serum interleukin-4 (IL-4), on the other hand, was undetectable before and during the transfusion protocol. By day 3 PT, recipient spleen cells could mediate in vitro anti-P815 (auto), anti-EL4 (allo), and anti-R1.1 (third-party MHC) cytotoxicity, and these responses were maximal by day 7 PT. Concurrently, a significant reduction in the vitro ability of recipient splenocytes to respond to Concanavalin A (ConA) was observed; this was not seen with lipopolysaccharide (LPS) stimulation. Elevated levels of NO2- were found in the ConA culture supernatants from transfused mice at day 3 PT. Serum antidonor alloantibodies were detected by the fifth platelet transfusion. AMG treatment of recipient mice significantly inhibited the transfusion. Induced cytotoxicity and ConA-stimulated NO2- production, and restored ConA-induced proliferation to normal levels. AMG appeared to selectively inhibit platelet-induced alloantibody production in that it did not affect antibody production induced by transfusions with 10(5) allogeneic leukocytes or by immunization with a foreign protein antigen, human gamma globulin, in adjuvant therapy. These results indicate that an in vivo AMG-sensitive mechanism is essential for recipients to initiate a humoral IgG immune response against allogeneic platelets.  相似文献   
90.
An abnormal increase in numbers of CCGG sites methylated in the 5' region of the human calcitonin (CT) gene occurred in tumor cell DNA samples from 90% (17 of 19) of patients with non-Hodgkin's T and B cell lymphoid neoplasms and in 95% (21 of 22) of tumor cell DNA samples from patients with acute nonlymphocytic leukemia (ANLL). The changes were not seen in patients with chronic myelogenous leukemia (0 of 9). The abnormal methylation patterns appear to be a property only of transformed or malignant cells since they were not found in DNA from nonneoplastic adult tissues including sperm, early myeloid progenitor cells, benign lymphoid hyperplasia, peripheral lymphocytes stimulated to divide, or early myeloid progenitor cells (obtained by immunoaffinity using anti-My-10 antibody), but they did appear after Epstein-Barr virus transformation of lymphocytes. Moreover, during the course of therapy in patients with ANLL, the hypermethylation pattern reflects the presence of the leukemic clone even in normal-appearing granulocytes derived from this clone. The increased methylation of the CT gene may then provide an important molecular marker for biologic events in human cell transformation or tumor progression and may prove clinically useful in monitoring patients with lymphoid and acute myelogenous neoplasms.  相似文献   
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