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We evaluated erectile haemodynamics in mice and characterized the corpus cavernosum morphologically. Four-month-old male BALB/c mice and Sprague-Dawley rats were used. The following stimulation parameters were tested to achieve maximal erectile responses: voltage, 1-6 V; frequency, 6-24 Hz; pulse width, 1 msec; duration, 1 min (n = 7 per group). In a separate group of mice and rats (n = 10 per group), we measured systemic arterial pressure by use of either a 24-gauge angiocatheter or smaller calibre PE-10 tubing. Cavernous tissues from mice, rats or patients with psychogenic erectile dysfunction were stained for factor VIII, alpha-actin and Masson trichrome. Electrical stimulation of the cavernous nerve in mice produced voltage-dependent erectile responses of up to 5 V, with the highest response at a frequency of 12 Hz. The maximal intracavernous pressure recorded at this stimulation parameter was comparable with that in rats. A PE-10 catheter was more reliable for measuring systemic arterial pressure in mice than was a 24-gauge angiocatheter, and the values recorded were similar between mice and rats. The content of endothelial cells, smooth muscle cells and collagen was similar between mice and rats. However, the cavernous tissue of both animals contained lesser amounts of smooth muscle cells and greater amounts of collagen than that of humans (p < 0.01). These results suggest that the mouse is a useful and technically feasible model for the study of penile erection and has functional and structural properties similar to those of rats.  相似文献   
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Purpose

To compare the perioperative relative renal function and determine predictors of deterioration and recovery of separate renal function in patients with renal stones >10 mm and who underwent mini-percutaneous nephrolithotomy or retrograde intra-renal surgery.

Patients and methods

A main stone >10 mm or stones growing, high-risk stone formers and extracorporeal shock-wave lithotripsy-resistant stones were prospectively included in 148 patients. Patients with bilateral renal stones and anatomical deformities were excluded. Renal function was evaluated by estimated glomerular filtration rate, 99m-technetium dimercaptosuccinic acid and 99m-technetium diethylenetriamine pentaacetate prior to intervention and at postoperative 3 months. Logistic regression analyses were performed to find predictors of functional deterioration and recovery.

Results

The overall stone-free rate was 85.1 %. A third of patients (53/148, 35.8 %) with renal stones >10 mm showed deterioration of separate renal function. Mean renal function of operative sites showed 58.2 % (36.8 %/63.2 %) of that of contralateral sites in these patients. Abnormal separate renal function showed postoperative recovery in 31 patients (58.5 %). Three cases (5.7 %) showed deterioration of separate renal function despite no presence of remnant stones. Improvement rates of the abnormal separate renal function did not differ according to the type of surgery. The presence of hydronephrosis and three or more stones were significant predictors for renal function deterioration. Female gender and three or more stones were significantly correlated with postoperative recovery.

Conclusions

Mini-percutaneous nephrolithotomy or retrograde intra-renal surgery was effective and safe for renal function preservation. Patients with multiple large stones should be considered for candidates of active surgical removal.
  相似文献   
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血脾屏障形态学的实验研究   总被引:5,自引:0,他引:5  
目的 探讨血脾屏障的形态学特征,研究其组成和变化规律,确立血脾屏障的概念。方法选用Wistar大鼠30只,其中10只经尾静脉注射碳粒。取脾脏组织制作病理切片进行HE染色、Foot染色、Masson染色、免疫组织化学染色(CD68、CD34)及透射电镜病理,观察血脾屏障的形态结构特征。结果碳粒在脾脏中围绕血脾屏障形成环状分布。巨噬细胞,血管内皮细胞,胶原纤维及网状组织在血脾屏障中均有特征性分布。结论血脾屏障是位于边缘区,环绕白髓存在的,窦周血管内皮细胞及其基膜、巨噬细胞、网状细胞和网状纤维(网状组织)及胶原纤维组成的生物屏障,它通过细胞间较致密结合的机械屏障作用和巨噬细胞的生物吞噬作用发挥抗原滤过作用,维持白髓的内环境稳态。它随生发中心的形成而逐渐成熟,通透性发生变化。  相似文献   
15.
目的:探讨慢性胰腺炎K-ras基因突变的临床病理学意义。方法:9例手术切除的慢性胰腺炎的石蜡标本,用微解剖法分离慢性胰腺炎的胰导管上皮粘液细胞增生灶,提取,扩增DNA,用ASO斑点杂交检测K-ras基因第12密码子的碱基序列。对9例接受手术治疗的病人进行长期随访,结果:9例慢性胰腺炎中4例有明显的胰导管上皮粘液细胞增生,其中2例被检出GAT型突变,分别占全组和有胰管上皮粘液细胞增生的22%和505,两个突变病例分别是接受了胰体尾切除和胰头十二指肠切除手术,术后分别随访17年和10年,没有发现任何恶变迹象,结构:慢性胰腺为可以检出K-ras基因突变,发生了K-ras基因突变的慢性胰腺炎上皮粘液细胞增生灶,未必一定发生为胰腺癌,胰液、粪便、末梢血液和尿液的检测,以及胰腺组织细针刺液检出K-ras基因突变,对胰腺癌的诊断有重要参考价值,但不应视为胰腺癌的确诊依据。  相似文献   
16.
Objective NaFeEDTA was considered as a promising iron fortificant for controlling iron deficiency anemia. Soy sauce is a suitable food carrier for iron fortification and is a popular condiment in China. Iron absorption rates of NaFeEDTA and FeSO4 were observed and compared in adult female subjects. Methods The stable isotope tracer method was used in Chinese females consuming a typical Chinese diet. Ten healthy young Chinese women were selected as subjects in the 15-day study. A plant-based diet was used based on the dietary pattern of adult women in the 1992 National Nutrition Survey. Six milligram of 54Fe in 54FeSO4 soy sauce and 3 mg 58Fe in Na58FeEDTA soy sauce were given to the same subjects in two days. Food samples and fecal samples were collected and analyzed. Results Iron absorption rates of NaFeEDTA and FeSO4 were 10.51%±2.83 and 4.73%±2.15 respectively. The 58Fe(NaFeEDTA) absorption was significantly higher than that of 54Fe(FeSO4)(P<0.01). The iron absorption rate from NaFeEDTA was 1.2 times higher than that from FeSO4 in Chinese adult women consuming a typical Chinese diet. Conclusion The higher absorption rate of NaFeEDTA suggested that NaFeEDTA would be a better iron fortificant used in soy sauce for the controlling of iron deficiency anemia in China.  相似文献   
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Radiofrequence ablation of liver cancers   总被引:4,自引:0,他引:4  
Primary and secondary malignant liver cancer are some of most common malignant tumors in the world. Chemotherapy and radiotherapy are not very effective against them. Surgical resection has been considered the only potentially curtive option, but the majority of patients are not candidates for resection because of tumor size, location near major intrahepatic blood vessels and bile ducts, precluding a margin-negative resection, cirrhotic, hepatitis virus infection or multifocial. Radiofrequence ablation (RFA), which is a new evolving effective and minimally invasive technique, can produce coagulative necrosis of malignant tumors. RFA should be used percutaneously, laparascopically, or during the open laparotomy under the guidance of ultrasound, CT scan and MRI. RFA has lots of advantages superior to other local therapies including lower complications, reduced costs and hospital stays, and the possibility of repeated treatment. In general, RFA is a safe, effective treatment for unresectable malignant liver tumors less than 7.0 cm in diameter. We review the principle, mechanism, procedures and experience with RFA for treating malignant liver tumors.  相似文献   
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