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Aging alters bladder functions where a decrease in filling, storage and emptying is observed. These changes cause urinary incontinence, especially in women. The aim of this study is to examine how aging affects the intracellular calcium movements due to agonist-induced contractions in permeabilized female rat bladder. Urinary bladder isolated from young and old female Sprague-Dawley rats were used. Small detrusor strips were permeabilized with β-escin. The contractile responses induced with agonists were compared between young and old groups. Carbachol-induced contractions were decreased in permeabilized detrusor from old rats compared to young group. Heparin and ryanodine decreased carbachol-induced contractions in young rats where only heparin inhibited these contractions in olds. Caffeine-induced contractions but not inositol triphosphate (IP3)-induced contractions were decreased in old group compared to youngs. The cumulative calcium response curves (pCa 8–4) were also decreased in old rats. Carbachol-induced calcium sensitization responses did not alter by age where GTP-β-S and GF-109203X but not Y-27632 inhibited these responses. Carbachol-induced contractions decrease with aging in rat bladder detrusor. It can be postulated as IP3-induced calcium release (IICR) is primarily responsible for the contractions in older rats where the decrease in carbachol contractions in aging may be as a result of a decrease in calcium-induced calcium release (CICR), rather than carbachol-induced calcium sensitization.  相似文献   
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PURPOSE: We systematically assessed the efficacy and safety of appetite stimulants in the management of cancer-related anorexia. Literature databases were searched for randomized controlled trials of appetite stimulants in the treatment of cancer anorexia. MATERIALS AND METHODS: Studies were graded according to quality. Fifty-five studies met inclusion criteria. RESULTS: Only two drugs have evidence to support their use for anorexia (progestins and corticosteroids). There is strong evidence against the use of hydrazine sulfate. The outcomes of these trials have been mixed and patient population heterogeneous. CONCLUSION: The optimal dose, time to start, and duration of treatment for many appetite stimulants for cancer anorexia is still unknown. A more systematic approach to research methodology with universal outcome measure and prospective randomized studies are need. Combination regimens are needed but this cannot at the present time be supported by the data presented.  相似文献   
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Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic pleiotropic effects have rarely been attributed to individual loci. We examine several classes of longevity-assurance genes: those involved in regulation of the gonad; the insulin-like growth factor pathway; free-radical scavenging; heat shock proteins and apoptosis. We find initial evidence that antagonistic pleiotropic effects are pervasive in each of these classes of genes and in various model systems--although most studies lack explicit studies of fitness components. This is particularly true of human studies. Very little is known about the early-life fitness effects of longevity loci. Given the possible medical importance of such effects we urge their future study.  相似文献   
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Multiple number of techniques and devices have been described concerning circumcision method so far. One of them is thermocautery device, and it has been widely used. Although there is controversy that the penis may be damaged due to the heat generated during the use of the device, not enough histopathological studies have been conducted. We aimed to determine the histopathological changes in human foreskin caused by heat after circumcision with thermocautery and to demonstrate the safety of the use of a thermocautery-assisted circumcision. Forty-one patients were divided into two groups according to the thermal energy used during cutting with thermocautery as follows: high temperature (Group 1, n = 22) and low temperature (Group 2, n = 19). The effect of the heat intensity and depth of the coagulation necrosis produced with thermocautery-assisted circumcisions performed at low and high temperatures were evaluated. The difference between the groups was not statistically significant. Tissue damage is extremely limited in thermocautery-assisted circumcisions, even when it is used at high temperatures. The thermocautery device can be used for effective and safe circumcisions.  相似文献   
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BACKGROUND: The aim of our study was to evaluate the effect of chordal transfer around the cleft on left atrioventricular valve competence in the late postoperative period. METHODS: Forty-four adult patients underwent surgical correction of partial atrioventricular septal defect between 1983 and 1997. Fenestration was found in 8 patients (18.2%) and cleft, in 35 (79.5%). There was no chordal support of the free edges of the left superior and left inferior leaflets around the cleft in 18 patients. Two chordae were mobilized from the left lateral leaflet and reimplanted into the tip of the left superior and left inferior leaflets around the cleft. RESULTS: At 5 years postoperatively, left atrioventricular valve insufficiency was severe in 5 patients and moderate in 11 patients who had had cleft closure alone. In contrast, severe valvular insufficiency was present in only 1 patient in the group with chordal transfer (p < 0.05). Reoperation was done in 5 patients with isolated cleft closure. Left AV valve replacement was performed in 1 patient. CONCLUSIONS: Chordal transfer plus cleft closure with interrupted sutures significantly reduces early and late left atrioventricular valve incompetence and also decreases the rate of reoperation.  相似文献   
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Aorta to pulmonary artery fistula is an uncommon and potentially fatal condition. This case is of a 48‐year‐old Caucasian male with congestive heart failure and multiple aortic valve replacement surgeries who presented with an acquired ascending aortic aneurysm to pulmonary artery fistula diagnosed using two‐dimensional transthoracic echocardiography via nonstandard imaging windows. Three‐dimensional transthoracic echocardiography using live/real time three‐dimensional color Doppler was used to assess the size of the opening of the fistula, providing additional value. This patient was surgically managed and is doing well 8 months postoperation.  相似文献   
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