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61.
62.
We report a rare case of a localized fibrosis of the corpus cavernosum (CC) presenting as a nodular mass in the dorsal region of the penis without abnormal curvature of the organ. Histological and immunohistochemical examination revealed a fibrotic process, involving CC but not tunica albuginea, arising from the smooth muscle cells of the vascular channels. Two different morphological phases were identified in these vascular lesions: proliferative and residual phase. The proliferative phase was characterized by hyperplasia and moderate fibrous thickness of the smooth muscle layer of the vascular channels of CC, resulting with the formation of concentric perivascular cuffs and nodules. The residual phase was characterized by a progressive nodular fibrotic transformation with narrowing of the original vascular channels and replacement of the normal CC structures. The cells of this phase exhibited an immunophenotype of both fibroblasts (vimentin+; alpha-smooth muscle actin-) and myofibroblasts (vimentin+; alpha-smooth muscle actin+). The clinicopathological features of the lesion and histogenetic considerations are discussed.  相似文献   
63.
Paclitaxel (Taxol) a clinically active anticancer agent, exerts its cytotoxicity by inducing tubulin polymerization, leading to cellular mitotic block. In contrast, other antimitotic drugs, such as colchicine, podophyllotoxin, and vinblastine, act by depolymerizing microtubules. We report here (a) a semiautomated assay which measures the tubulin-polymerizing activity of paclitaxel analogs and (b) a cellular assay to measure the potential of these compounds to block cells in mitosis. The microtubule-polymerizing assay measured the turbidity of bovine brain microtubule protein (MTP) polymerized by the test compound in a 96-well plate. We maximized the sensitivity of this assay by conducting the polymerization reaction at 20 °C, at which temperature the baseline reaction, i.e. the basic ability of the untreated MTP control to polymerize, was minimal. At 20 °C, the effect of 0.05 μg/ml of paclitaxel on MTP could be detected, whereas at 37 °C, >1 μg/ml of paclitaxel was required to detect a significant effect relative to untreated MTP. We describe the analysis of the complex curves of MTP polymerization with varying concentrations of test compounds. The polymerization of microtubules leads to cells being blocked in mitosis. This mitotic blocking effect in intact cells was determined using a cell settling chamber which allowed eight samples to be deposited on a slide. This method required a smaller number of cells (103–105), maintained cell morphology, and allowed for rapid screening of samples. The activity of several new paclitaxel analogs is reported. Received: 9 May 1996 / Accepted: 5 March 1997  相似文献   
64.
Determination of obstructive site in obstructive sleep apnoea (OSA) is of paramount importance is planning the management. Cephalometric evaluation of lateral X-rays when combined with clinical assessment and fibreoptic examination of the airway helps in locating the site of obstruction. The usual technique of cephalometry has been modified so as to give a better delineation of the soft tissues. Holding a 2mm card board in the mouth and using barium paste helped in more accurate calculations. Using our technique, various parameters have been quantified and a number of controls were studied and normal range derived. Further improvement in cephalometry has been done by using C.T. cephlometry topogram technique. A topogram is a scan done on a running table top cranio-caudally. Using the topogram technique 38 OSA patients were evaluated for all the parameters. The technique, its advantages over traditional cephalometry and the values obtained in the study are discussed in this paper.  相似文献   
65.
OBJECTIVE: To study the patterns and determinants of psychoactive drug use by Lisbon University students. MATERIALS AND METHODS: A cross-sectional survey was conducted, from January to April 2000, in a probabilistic sample of 1,147 students. Information about use of psychoactive drugs and co-variates was collected by a questionnaire administered by trained interviewers. Psychoactive drugs were considered to be all medicines classified in group N (nervous system) of the ATC system except the anesthetics (subgroup N01) and the analgesics (subgroup N02). RESULTS: 91 students (7.9%) had taken psychoactive drugs during the fortnight before the interview, 39 of whom (42.8%) mentioned continuous use. The prevalence of use was significantly higher in females (9.6%), older than 25 years (13.1%), married (16%), who considered themselves to have a weak health status (21.7%), as under intense stress (15.5%). After adjustment by multivariate analysis the variables sex, self-evaluation of health status and daily stress retained a higher significant association with psychoactive drug use. A total of 132 drugs were reported as being used in that period. Tranquilizers (ATC = N05B or N05C) were used by 82 students (7.2%), while 22 (1.9%) consumed psychoactive stimulants (N06B) and 19 (1.7%) antidepressants (N06A). In all of these therapeutical subgroups, females had higher consumption prevalence than males, but the difference was statistically significant only for tranquilizers (P < 0.001). Anxiety, depression and insomnia were the most frequently stated health problems. More than 90% of drug consumers considered they had a compliant attitude and about 60% considered themselves well-informed about adverse effects of the drug used. The reported prevalence of self-medication for psychoactive drugs used was 12.8%. CONCLUSIONS: The prevalence of psychoactive drug use among students of Lisbon University was higher than expected, considering age group and the usual health status of this population. The administration of a questionnaire was a very useful tool to characterise the pattern of use and the consumer's knowledge about the drugs consumed.  相似文献   
66.
Psoas abscess (PA) is an infrequent clinical entity and presents diagnostic and therapeutic challenges. Six cases are reported concerning diagnostic and therapeutic considerations. Clinical diagnosis is difficult because of non-specific symptoms. The primary psoas abscess has no definite etiology and is spread by hematogeneous route from a distant occult site. The PA can also be secondary to gastrointestinal pathology through direct infection of adjacent structures. The most common causes are Crohn's disease, appendicitis, diverticulitis and carcinoma. Routine laboratory evaluation is seldom useful for localizing the disease process. Conventional radiological techniques are often unhelpful. Modern imaging diagnosis techniques such as ultrasound and computerized tomography have allowed for a refinement in both the etiologic diagnosis and the treatment by means of CT-guided or ultrasound-guided percutaneous drainage of the abscess, thus avoiding surgical drainage in many cases. Immediately on diagnosis of PA prompt treatment is necessary. Percutaneous drainage should be performed whenever possible and in case of failure, surgical drainage should be practiced as well as intestinal resection, whenever indicated.  相似文献   
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68.
Background:School-aged children often participate in type 1 diabetes (T1D) self-care tasks. Despite widespread discussion about the importance of developing self-care skills in childhood, few explain how the health care team should assess the skills of children with T1D when performing insulin injections.Objective:We sought to assess content validity evidence in two checklists regarding injection technique performed by children.Methods:Two checklists were designed based on a systematic review of the insulin injection technique. Experts in pediatric diabetes, health literacy, and diabetes education assessed the checklists regarding their clarity, objectivity, and relevance. Content validity was assessed using the content validity ratio (CVR).Results:Eleven providers (72% nurses or physicians, professional experience 19.4 ± 10.1 years, 45% of specialists in endocrinology, and 18% in pediatrics) participated in the assessment. Experts considered items containing the word homogeneity inappropriate. Items related to the needle insertion angle and the skin fold did not reach the CVR critical value. The final version of the checklist for syringe injection comprised 22 items with CVR = 0.91, and the checklist for pen injection comprised 18 items with CVR = 0.87.Conclusions:The checklists presented clear, objective, and relevant content that assesses the skills of children with T1D for insulin injection. The checklists formally present the order of the technique and all the steps for insulin injection and allow a quantitative assessment of the operational skills of children. The developed instruments offer providers the possibility of continuous assessment of the progress of the pediatric clientele until they reach independence in diabetes self-care.  相似文献   
69.
Over the past decade, interest in drugs derived from medicinal plants has markedly increased. This study was aimed at a literature review focusing on studies investigating herbal drugs and other natural products, as well as their therapeutic application, side effects and possible drug interactions. Few studies were found to support their rational use in dentistry. Since there is an increasing use of phytotherapeutic agents in dentistry, further studies are needed to evaluate their safety and effectiveness for clinical use.  相似文献   
70.
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