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The original article to which this Erratum refers was published in Human Psychopharmacology: Clinical and Experimental 16 (3) 2001, 247-255.  相似文献   
74.
BACKGROUND/AIMS: To examine the role of apoptosis in experimental unilateral ureteral obstruction (UUO). METHODS: Rat kidneys were examined 3, 7 and 11 days following UUO or sham operation (SO). Tissue was immunohistochemically stained for alpha-smooth muscle actin (alpha-SMA), proliferating cell nuclear antigen (PCNA), Bcl-2 and Bax proteins. Apoptotic analysis was carried out in kidney sections using in situ end labelling of endonuclease cleaved DNA. RESULTS: The relative volume (Vv) of cortical interstitium and interstitial alpha-SMA increased progressively following UUO. ED1-positive monocytes/macrophages peaked at day 7 and significantly decreased at day 11. PCNA-positive cells in tubulointerstitium were significantly increased on day 3. Staining returned to the level of the SO group by day 11, meanwhile those in the interstitium remained much higher than baseline. TUNEL-positive cells were persistently raised following UUO. Transient tubular cell proliferation seemed unable to counteract the apoptosis since tubular atrophy was apparently present by day 11 of UUO. However, interstitial cell proliferation was high enough to overwhelm apoptosis, particularly with respect ot myofibroblasts, since alpha-SMA immunostaining and Vv remained elevated. The ratio of the number of PCNA-positive cells to apoptotic cells formed a predictive pattern for the staining score of interstitial alpha-SMA (R(2) = 47.23%, p < 0.05) and Vv (R(2) = 49.93%, p < 0.05). Tubular Bcl-2 immunostaining peaked on day 3, and then gradually decreased to baseline by day 11. The expression of Bax protein was inhibited on day 3 when compared with that of the SO group, but increased with time following UUO. CONCLUSION: These findings suggest an important role for apoptosis and its regulatory proteins in the processes of tubular atrophy and fibrogenesis following UUO.  相似文献   
75.
Apoptosis has been proposed to play an important role in the progression of renal scarring. The mechanisms that determine whether a cell enters the apoptotic program are complex. Bax and Bcl-2 are recognized modulators of this event; their relative levels determine the fate of cells. A role for apoptosis in the progression of renal scarring in the remnant kidneys of rats submitted to subtotal nephrectomy (SNx) has been described. This study investigated the expression (protein and mRNA) of Bax and Bcl-2 in remnant kidneys between day 7 and day 120 post-SNx. Northern blot analysis showed that bax mRNA was increased in remnant kidneys from day 7 (150% of control; P: < 0.05), whereas bcl-2 mRNA was decreased from day 15 (23% of control; P: < 0.05) resulting in a 14-fold increase in the ratio of bax to bcl-2 mRNA by day 120. Western blot analysis showed similar changes in Bax and Bcl-2 protein in remnant kidneys, resulting in a 147-fold increase in the ratio of Bax to Bcl-2 on day 120. Immunohistochemistry showed increases in Bax to be located predominantly in tubules in SNx kidneys. Interestingly, Bcl-2 immunostaining increased in some epithelial cells within atrophic tubules despite the overall decrease in Bcl-2 protein and mRNA. The overall renal apoptotic cells correlated closely with the ratio of bax to bcl-2 at both the mRNA and protein levels (r = 0.594 and 0.308, respectively; P: < 0.05). Furthermore, tubular apoptosis correlated positively with the mRNA level of bax (r = 0.471; P: < 0.01) and negatively with the mRNA and protein levels of bcl-2 (r = -0.443 and -0.607, respectively; P: < 0.01). The increase in the ratio of the death inducer (Bax) to the death repressor (Bcl-2) at the mRNA and protein levels may control the apoptosis associated with the progression of tubular atrophy and chronic renal fibrosis within remnant rat kidneys. These observations may have prognostic and therapeutic implications in chronic renal failure.  相似文献   
76.
Cognitive impairment in multiple domains is common in patients with schizophrenia and may be a powerful determinant of poor functional ability and quality of life. We report a double-blind, placebo-controlled, cross-over study of donepezil augmentation in a schizoaffective disorder patient stabilized on olanzapine pharmacotherapy. The patient showed significant improvements in several cognitive measures and increased activation of prefrontal cortex and basal ganglia on functional MRI during the donepezil augmentation. In addition, the donepezil augmentation resulted in a reduction of depressive symptoms and in significant improvements in functional abilities and quality of life. Further studies of donepezil augmentation of neuroleptics in schizophrenia are warranted.  相似文献   
77.
This paper addresses the issues surrounding clinical credibility and describes how a Hong Kong specialist nurse teacher maintains clinical credibility. The aim is to explore the credibility of the nurse teacher in relation to the clinical knowledge and skills that will enhance postgraduate students' clinical scholarship. The paper describes a model for maintaining specialist teachers' clinical credibility and innovative strategies to achieve this goal.  相似文献   
78.
CONTEXT: Highly active antiretroviral therapy (HAART) has turned human immunodeficiency virus (HIV) infection into a chronic condition, and this has led to increased incidence of anal dysplasia among HIV-positive patients. Routine anal evaluation including the anal canal and perianal area is recommended for this population, especially for patients infected by oncogenic human papillomavirus (HPV) types. CASE REPORT: A 54-year-old homosexual HIV-positive man presented with a six-year history of recurrent perianal and anal warts. He had previously undergone incomplete surgical excision and fulguration in another institution on two occasions. He had been using HAART over the past two years. He presented some condylomatous spreading lesions occupying part of the anal canal and the perianal skin, and also a well-demarcated slightly painful perianal plaque of dimensions 1.0 x 1.0 cm. Both anal canal Pap smears and biopsies guided by high-resolution anoscopy revealed high-grade squamous intraepithelial lesion. Biopsies of the border of the perianal plaque also revealed high-grade squamous intraepithelial lesion. HPV DNA testing of the anus detected the presence of HPV-16 type. The patient underwent local full-thickness excision of the lesion. Histological analysis on the excised tissue revealed high-grade squamous intraepithelial lesion with one focus of microinvasive squamous cell cancer measuring 1 mm. No lymph vessel or perineural invasion was detected. The patient showed pathological evidence of recurrent anal and perianal high-grade squamous intraepithelial lesions at the sixth-month follow-up and required further ablation of those lesions. However no invasive squamous cell carcinoma recurrence has been detected so far.  相似文献   
79.

Background

Several studies have demonstrated skills transfer after virtual reality (VR) simulation training in laparoscopic surgery. However, the impact of VR simulation training on transfer of skills related to laparoscopic colectomy remains not investigated. The present study aimed at determining the impact of VR simulation warm-up on performance during laparoscopic colectomy in the porcine model.

Methods

Fourteen residents naive to laparoscopic colectomy as surgeons were randomly assigned in block to two groups. Seven trainees completed a 2-h VR simulator training in the laparoscopic sigmoid colectomy module (study group). The remaining seven surgeons (control group) underwent no intervention. On the same day, all participants performed a sigmoid colectomy with anastomosis on a pig. All operations were video recorded. Two board-certified expert colorectal surgeons independently assessed performance during the colectomy on the swine. Examiners were blinded to group assignment. The two examiners used a previously validated clinical instrument specific to laparoscopic colectomy. The primary outcome was the generic and specific skills score values.

Results

Surgeons undergoing short-duration training on the VR simulator performed significantly better during laparoscopic colectomy on the pig regarding general and specific technical skills evaluation. The average score of generic skills was 17.2 (16.5–18) for the control group and 20.1 (16.5–22) for the study group (p = 0.002). The specific skills average score for the control group was 20.2 (19–21.5) and 24.2 (21–27.5) for the study group (p = 0.001). There was acceptable concordance (Kendall’s W) regarding the video assessment of generic (W = 0.78) and specific skills (W = 0.84) between the two examiners.

Conclusions

A single short-duration VR simulator practice positively impacted surgeons’ generic and specific skills performance required to accomplish laparoscopic colectomy in the swine model.  相似文献   
80.
放线瑞香宁碱的解热镇痛作用   总被引:1,自引:0,他引:1  
洪庚辛  滕忠  覃文才  韦宝伟 《药学学报》1988,23(10):779-782
从青藤科植物黑吹风(Illigera sp)总生物碱中分离出一个单体,经化学鉴定命名为放线瑞香宁碱(actinodapbnine简称Ac)。分子式C_(18)H_(17)NO_4,为10-甲氧基-1,2-(次甲二氧基)-6-去甲阿朴菲-9-醇(图1)。动物实验表明,Ac具有解痉、镇痛、局麻及降低小鼠体温等作用,并证明其镇痛作用系非中枢性。本文进一步研究其镇痛作用和对不同动物正常  相似文献   
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