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1.
BACKGROUND: Most of our knowledge concerning obstructive uropathy has been derived mainly from surgically manipulated animal models, and the pathogenesis of congenital obstructive hydronephrosis is not fully elucidated. Nitric oxide (NO) acts as an important biological modulator with diverse physiological functions, which can be either toxic or protective depending on the situation. NO is synthesized from l-arginine by nitric oxide synthase, and in the kidney iNOS is expressed spontaneously. The aim of our study is to investigate the expression of iNOS protein and its relationship with tubulointerstitial fibrosis and tubular cell apoptosis in congenital hydronephrosis. METHODS: We conducted histological studies on 18 kidneys of six-week-old-rats from an inbred colony of congenital hydronephrosis with reference to the histological grading of the affected kidney, tubulointerstitial fibrosis, renal tubular atrophy, and tubular cell apoptosis. Renal transforming growth factor-beta1 (TGF-beta1) level was determined by a sandwich ELISA assay and the expression of iNOS was analyzed by western blotting. RESULTS: Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. Renal TGF-beta1 level was higher in hydronephrotic kidneys than normal control kidneys (364.81 +/- 52.60 vs. 221.19 +/- 22.53 pg/mg protein, P < 0.05). Tubular apoptotic score in hydronephrotic kidneys was also significantly higher than in the normal control kidneys (1.97 +/- 0.42 vs. 0.14 +/- 0.02/HPF, P < 0.01). The expression of iNOS protein was lower in the affected kidneys compared with the normal control kidneys (8.79 +/- 0.78 vs. 14.00 +/- 0.83 arbitrary unit, P < 0.01). There was a negative correlation between iNOS expression and histological grading in congenital hydronephrosis. The iNOS expression also correlated negatively with renal interstitial fibrosis, TGF-beta1 level and tubular cell apoptosis. CONCLUSION: Our study confirmed the down-regulation of iNOS expression in affected kidneys from rats with congenital hydronephrosis, in which the cytoprotective effect of NO may be lost or weakened.  相似文献   
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The effects of camostat mesilate, a synthetic serine protease inhibitor on gastric microcirculation and active oxygen species generated by leucocytes from the gastric and jugular veins in the early period after thermal injury were assessed. Male Wistar rats were anaesthetized and a 30% full skin-thickness dorsal burn was inflicted. Camostat mesilate (100 mg/kg) was dissolved in distilled water and administered orally to rats 40 min before thermal injury (the camostat group). The control animals (the vehicle group) were administered distilled water orally. Rolling leucocytes as well as Monastral blue B deposits in venules were observed using in vivo microscopy. Active oxygen species were measured by chemiluminescence. Camostat mesilate decreased the total length of gastric erosion, venular deposits of Monastral blue B, and rolling of leucocytes in venules, and relatively increased luminol-dependent chemiluminescence activity generated by zymosan-stimulated leucocytes 15 min after thermal injury. These results suggest that serine proteases are involved in the formation of gastric erosions and gastric microcirculatory disturbance in the early period after thermal injury.  相似文献   
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目的:体外分离、扩增成人骨髓间质干细胞(MSCs)和向内皮细胞(ECs)定向诱导分化,开辟心血管组织工程种子细胞的新来源。 方法: 采用Percoll(1 073 g/L)从正常成人骨髓中分离出MSCs,纯化和扩增后流式细胞仪鉴定其纯度;用血管内皮生长因子(VEGF)诱导MSCs向ECs分化,Ⅷ因子(vWF)免疫组化和透射电镜(TEM)鉴定细胞性质。 结果: 5.0×105个MSCs在体外扩增15代后,获得8.0×1012个MSCs,扩增了约1.6×107倍;MSCs在加入VEGF诱导培养大约14-21 d,80%-90%的诱导细胞对Ⅷ因子相关抗原呈阳性反应;TEM可观察到胞浆内有Weible-palade小体,证实为ECs。 结论: 成人骨髓MSCs在体外具有定向诱导分化为ECs的潜能,这为心脏组织工程瓣体外构建, 尤其是在小儿先天性心脏病组织工程研究中种子细胞的来源提供了可能性。  相似文献   
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We compared the effects of exogenous pentagastrin and meal-stimulated gastrin on plasma immunoreactive calcitonin (iCT) in various studies of 13 normal adult men. Bolus intravenous injection of pentagastrin (0.5 μg/kg) produced increases of iCT in 8 of 9 men. There was a linearly increasing response of iCT concentrations to increasing doses of pentagastrin (0.0625, 0.125, 0.25, and 0.5 μg/kg) and to achieved serum immunoreactive pentagastrin concentrations (r=0.72, P<0.01). To determine the effects of endogenous gastrin upon peripheral iCT concentrations, we measured serum immunoreactive gastrin (iG) and plasma iCT in four men at frequent intervals for 240 min after ingestion of low-(100 mg) and high- (400 mg) calcium meals. Serum iG increased in all subjects, with a peak at ~30 min. However, plasma iCT levels were unchanged from basal throughout the study. The increase of pentagastrin (0.3 pmol/ml) which caused a barely detectable increase of iCT was five-to tenfold greater than the mean maximal increases of gastrin after low- and high-calcium meals (0.04 and 0.06 pmol/ml, respectively). These results suggest that increases of plasma iCT concentrations after administration of pentagastrin in man reflect pharmacologic phenomena and that postprandial gastrin secretion may be insufficient to affect peripheral iCT concentrations.  相似文献   
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The response to cardiopulmonary exercise (CPX) in patients with heart failure (HF) with normal left ventricular (LV) ejection fractions (EFs) is not well characterized. To determine if CPX testing could distinguish between patients with HF with normal EFs (>50%; i.e., diastolic HF) and those with decreased EFs (> or =50%; i.e., systolic HF), CPX responses were compared between 185 patients with systolic HF (79% men, mean age 62.6 +/- 10.9 years) and 43 with diastolic HF (54% men, mean age 67.4 +/- 9.8 years) enrolled in a phase II multicenter clinical trial. All patients were evaluated with echocardiography and a standardized CPX test as part of the trial. CPX variables, including oxygen uptake at peak exercise (peak VO(2)) and the slope of the ventilation/carbon dioxide production ratio (VE/VCO(2)), were determined and analyzed by core laboratory personnel. Echocardiographic measurements included the LV EF, the E/A ratio, filling time, cavity volumes, right ventricular function, and mitral regurgitation. Patients in the diastolic HF group tended to be older (p <0.08), with more women (p <0.006) and with greater body mass indexes (p <0.02), than those in the systolic HF group. There was no significant difference in the use of beta blockers or the incidence of coronary artery disease. Patients with diastolic HF had decreased E/A ratios (0.9 +/- 0.4 vs 1.4 +/- 1.1, p <0.02, diastolic HF vs systolic HF) and increased filling times (30.4 +/- 3.2 vs 26.5 +/- 4.7 ms, p <0.01, diastolic HF vs systolic HF). No significant differences in peak VO(2) (14.4 +/- 1.9 vs 15.6 +/- 3.2 ml/kg/min, p = 0.06, diastolic HF vs systolic HF) were observed. The VE/VCO(2) ratios for the 2 groups were abnormal and comparable (32 2 +/- 7.5 vs 34.0 +/- 8.3, p = 0.3, diastolic HF vs systolic HF). In conclusion, the CPX response in patients with diastolic HF and systolic HF is markedly abnormal and indistinguishable with regard to peak VO(2) and ventilation despite marked differences in the LV EF.  相似文献   
7.
Abstract Helicobacter pylori infection is the most common cause of duodenal ulcer disease, yet duodenal ulcer is an uncommon outcome of H. pylori infection. We reviewed the possible explanations such as differences in the host or in the strain of H. pylori. Host factors reviewed included genetic susceptibility to H. pylori infection and excess gastric acid secretion. The role of potential H. pylori virulence factors not present in all strains such as the cagA gene and the results of other molecular methods to identify disease-specific differences among isolates was also reviewed. Although cure of H. pylori infection resolves gastrin releasing peptide stimulated acid secretion there was no change in parietal cell mass. Twin studies have shown genetic differences in H. pylori susceptibility. There was no difference in the prevalence of the cagA gene between H. pylori infected asymptomatic volunteers and duodenal ulcer patients ( P = 1.0). DNA-DNA hybridization of whole genomic DNA in solution and cluster analysis of rep-PCR genomic DNA fingerprints suggest that isolates from patients with duodenal ulcer disease are different from those obtained from individuals with asymptomatic gastritis. Cluster analysis of the rep-PCR DNA fingerprints revealed two major groups of the strains; one set consisted of strains from patients with duodenal ulcer disease and the second cluster consisted largely of strains from individuals with asymptomatic gastritis. Recent molecular studies suggest that disease-specific cell lineages or strains may exist among H. pylori isolates leading to the various outcomes observed in patients with H. pylori infection.  相似文献   
8.
目的研究直立式聚丙烯输液袋(简称直立式输液袋)壁厚度对袋体输液性能的影响,寻求输液袋各参数随壁厚度改变的变化规律。方法针对标示容量为100、250、500mL3种直立式输液袋,分别设置4种不同壁厚度(n2、n3、0.4、0.5mm),采用有限元方法模拟排液过程.研究直立式输液袋应力分布、实际加药空间及排空率等参数的变化规律。结果在标示容量一定的条件下.100mL的直立式输液袋应力随壁厚度变化不显著;250mL直立式输液袋随壁厚度的增加应力逐渐减小.最大应力降幅为65%:500mL直立式输液袋壁厚度为0-2~0.3mm时,应力变化不明显,而壁厚度由0.3mm到0.5mm,最大应力下降28%。3种直立式输液袋的实际加药空间、排空率和袋壁接触面积均随壁厚度的上升而降低,100mL直立式输液袋为27%、11%和67%,250mL直立式输液袋为54%、11%和38%,500mL直立式输液袋为49%、11%和43%。结论综合考虑应力分布、实际加药空间、排空率和袋壁接触面积等参数的变化规律,直立式输液袋壁厚度不宜过大。在所考虑的壁厚度参数中.最佳壁厚度为0.2mm,但最终的壁厚度确定还需要综合考虑直立式输液袋的透气、透湿性和抗穿刺能力等因素。  相似文献   
9.
目的探讨拇指末节皮肤软组织缺损岛状皮瓣修复的临床疗效。方法从2009年4月至2011年6月,对收治的45例(45指)拇指指端皮肤软组织缺损的患者分别采用示指背侧顺行岛状皮瓣、拇指尺背侧逆行岛状皮瓣、虎口背侧逆行岛状皮瓣、大鱼际桡侧逆行岛状皮瓣和指动脉侧方神经血管蒂岛状皮瓣等5种岛状皮瓣修复。通过术后随访,比较各种皮瓣的治疗效果、治疗优缺点和最佳适应损伤类型。结果45例皮瓣全部成活,植皮区I期愈合。术后1例虎口背侧逆行岛状皮瓣和1例拇指尺背侧逆行岛状皮瓣远端皮缘部分坏死,经伤口换药后,均成活。所有患者均获得随访,随访时间6—24(15.7±2.1)个月,末次随访时,皮瓣外观恢复满意,质地柔软,弹性好,未见明显色素沉着,拇指活动、对掌功能及皮肤感觉均恢复良好。结论拇指尺背侧逆行岛状皮瓣、虎口背侧逆行岛状皮瓣、大鱼际桡侧逆行岛状皮瓣和指动脉侧方神经血管蒂岛状皮瓣是修复拇指指端缺损的有效方法,临床治疗各有优点,临床可根据拇指皮肤缺损特点,选择最佳皮瓣治疗。  相似文献   
10.
目的 探讨远端蒂腓肠神经营养血管皮瓣的近端位置对皮瓣部分坏死的影响.方法 回顾性分析2001年4月至2009年5月应用远端蒂腓肠神经营养血管皮瓣转移修复小腿下段及足踝部创面的病例资料,共153位患者157例皮瓣.将小腿后面从外踝尖至腘窝横纹等分为9个区,从下至上依次为第1至第9区.皮瓣分为成活组(包括完全成活、远端表皮坏死和伤口裂开的皮瓣)和部分坏死组;根据皮瓣近端位置,将皮瓣分为近端不超过第6区(A组)、位于第7区(B组)、第8区(C组)和第9区即小腿上1/9区段(D组)4个组.皮瓣采用顺逆结合法切取.结果 皮瓣完全成活125例;远端表皮坏死8例,远端伤口裂开6例;远端部分坏死18例(11.5%).A、B、C和D组皮瓣部分坏死率分别为0(0/19)、2.3%(1/44)、11.3%(7/62)和31.3%(10/32),A组与B组、B组与C组比较,皮瓣部分坏死率的差异均无统计学意义(P>0.05);皮瓣部分坏死率:D组高于C组(P=0.012)、近端位于小腿下7/9区域的皮瓣(1.6%,1/63)低于小腿上2/9区域的皮瓣(18.1%,17/94),差异均有统计学意义(P=0.001).结论 远端蒂腓肠神经营养血管皮瓣的近端不超过小腿下7/9与上2/9交界线时,皮瓣成活可靠;皮瓣近端位于小腿上1/9区段时,皮瓣部分坏死的可能性明显增大.  相似文献   
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