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101.
Chronic wounds are characterized by failure in wound-healing response and a delay in healing or nonclosure of the wounds. This results in a high effort in clinical treatment and/or home care. A major difference between acute wounds and chronic wounds is the imbalance of proteinase inhibitors and proteinase activity that regulates the degradation and regeneration of the extracellular matrix proteins. Collagen and collagen/oxidized regenerated cellulose dressings act as a competitive substrate for matrix metalloproteinase-2, matrix metalloproteinase-9, and bacterial collagenase and influence this imbalance positively. Both wound dressings, approved for chronic wound treatment, the bovine collagen type I sponge and the oxidized regenerated cellulose collagen sponge, did not differ significantly in their sorption profiles for all enzymes. In general, binding was enhanced with a longer incubation time. The density of the device and the accessible surface, which can be controlled by the manufacturing process, are the crucial factors for the efficiency of the wound dressing.  相似文献   
102.
PURPOSE: Ureteral stents are common devices in urological practice. However, a stent may provoke lower urinary tract symptoms that severely affect quality of life. We evaluated the relationship between ureteral stents and male erection/female sexuality. MATERIALS AND METHODS: A total of 30 men and 20 women undergoing ureteral stent positioning were considered. Patients affected by risk factors for erectile dysfunction or hormonal and metabolic alterations were excluded. Hystero-ovariectomy and menopause were considered exclusion criteria. Three questionnaires were administered before stenting and 45 to 60 days after stent positioning, including the International Prostate Symptom Score, the International Index of Erectile Function-5 for men and the Female Sexual Function Index for women. RESULTS: Mean age was 45 years in men and 39 years in women. The mean+/-SD International Index of Erectile Function-5 score was 23.2+/-1.27 and the mean Female Sexual Function Index score was 32.15+/-2.71 before stent positioning. No lower urinary tract symptoms were reported before the procedure. After the ureteral stent was indwelling the mean International Index of Erectile Function-5 score was 13.5+/-4.01 and the mean Female Sexual Function Index score was 23.6+/-14.66 (p=0.000 and 0.007, respectively). Of 30 men 25 reported a pathological International Index of Erectile Function-5 score and 6 of 20 women denied any sexual activity due to stent related anxiety, resulting in the minimum Female Sexual Function Index score. In the remaining 14 women sexual life was not significantly impaired by the ureteral stent (p=0.08). CONCLUSIONS: Ureteral stents impaired the quality of sexual life in male and female subjects. In men the most important distress was in regard to erectile function, probably related to lower urinary tract symptoms. Conversely female sexuality appeared to be severely impaired due to stent related psychological concerns.  相似文献   
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104.

Introduction

The treatment of portal hypertension is complex and the the best strategy depends on the underlying disease (cirrhosis vs. schistosomiasis), patient''s clinical condition and time on it is performed (during an acute episode of variceal bleeding or electively, as pre-primary, primary or secondary prophylaxis). With the advent of new pharmacological options and technical development of endoscopy and interventional radiology treatment of portal hypertension has changed in recent decades.

Aim

To review the strategies employed in elective and emergency treatment of variceal bleeding in cirrhotic and schistosomotic patients.

Methods

Survey of publications in PubMed, Embase, Lilacs, SciELO and Cochrane databases through June 2013, using the headings: portal hypertension, esophageal and gastric varices, variceal bleeding, liver cirrhosis, schistosomiasis mansoni, surgical treatment, pharmacological treatment, secondary prophylaxis, primary prophylaxis, pre-primary prophylaxis.

Conclusion

Pre-primary prophylaxis doesn''t have specific treatment strategies; the best recommendation is treatment of the underlying disease. Primary prophylaxis should be performed in cirrhotic patients with beta-blockers or endoscopic variceal ligation. There is controversy regarding the effectiveness of primary prophylaxis in patients with schistosomiasis; when indicated, it is done with beta-blockers or endoscopic therapy in high-risk varices. Treatment of acute variceal bleeding is systematized in the literature, combination of vasoconstrictor drugs and endoscopic therapy, provided significant decline in mortality over the last decades. TIPS and surgical treatment are options as rescue therapy. Secondary prophylaxis plays a fundamental role in the reduction of recurrent bleeding, the best option in cirrhotic patients is the combination of pharmacological therapy with beta-blockers and endoscopic band ligation. TIPS or surgical treatment, are options for controlling rebleeding on failure of secondary prophylaxis. Despite the increasing evidence of the effectiveness of pharmacological and endoscopic treatment in schistosomotic patients, surgical therapy still plays an important role in secondary prophylaxis.  相似文献   
105.
Lifestyle and dietary factors may influence the association of IL-6 polymorphisms with bone mass. In 1574 unrelated men and women from the Framingham Offspring Cohort, we observed significant hip BMD differences between IL-6 -174 genotypes only in older women, those without estrogens, and those with a poor calcium intake. Hence, association of IL-6 polymorphisms with BMD may be limited to discrete population subgroups. INTRODUCTION: Interleukin (IL)-6 plays a central role in the pathogenesis of osteoporosis. Two functional variants in the IL-6 promoter have previously been associated with IL-6 expression, bone resorption levels, and BMD in late postmenopausal women, but results were conflicting in different populations. We hypothesized that the association between IL-6 promoter alleles and BMD may be affected by interactions with lifestyle and dietary factors known to influence bone turnover. MATERIALS AND METHODS: Among the Offspring Cohort of the Framingham Heart Study, 1574 unrelated men and women were genotyped for IL-6 -572 and -174 alleles. Interaction analyses with years since menopause, estrogen status, physical activity, smoking, dietary calcium, vitamin D, and alcohol intake were based on BMD measurements at the hip. RESULTS AND CONCLUSIONS: In models that considered only the main effects of IL-6 polymorphisms, no significant association with BMD was observed in either gender. In contrast, p values (0.003-0.096 by ANOVA) suggestive of an interaction between IL-6 -174 genotypes and years since menopause, estrogen status, dietary calcium, and vitamin D intake were observed in women (n = 819). In turn, BMD was significantly lower with genotype -174 GG compared with CC, and intermediate with GC, in women who were more than 15 years past menopause and in those without estrogens or with calcium intake <940 mg/day. In estrogen-deficient women with poor calcium intake, BMD differences between genotypes CC and GG were 10.2% at femoral neck (p = 0.012), 12.0% at trochanter (p = 0.012), and 16.8% at Ward's area (p = 0.0014). In contrast, no such interactions were observed in men (n = 755). In conclusion, IL-6 genetic variation was prominently associated with hip BMD in late postmenopausal women, those without estrogen replacement therapy, and those with inadequate calcium intake. In contrast, IL-6 polymorphisms are unlikely to be significant determinants of bone mass in other women or men.  相似文献   
106.
Background: Short administration of volatile anesthetics preconditions myocardium and protects the heart against the consequences of subsequent ischemia. Activation of tyrosine kinase is implicated in ischemic preconditioning. The authors investigated whether desflurane-induced preconditioning depends on activation of tyrosine kinase.

Methods: Sixty-four rabbits were instrumented for measurement of left ventricular pressure, cardiac output, and myocardial infarct size (IS). All rabbits were subjected to 30 min of occlusion of a major coronary artery and 2 h of subsequent reperfusion. Rabbits underwent a treatment period consisting of either no intervention for 35 min (control group, n = 12) or 15 min of 1 minimum alveolar concentration desflurane inhalation followed by a 10-min washout period (desflurane group, n = 12). Four additional groups received the tyrosine kinase inhibitor genistein (5 mg/kg) or lavendustin A (1.3 mg/kg) at the beginning of the treatment period with (desflurane-genistein group, n = 11; desflurane-lavendustin A group, n = 12) or without desflurane inhalation (genistein group, n = 9; lavendustin A group, n = 8).

Results: Hemodynamic values were similar in all groups during baseline (left ventricular pressure, 87 +/- 14 mmHg [mean +/- SD]; cardiac output, 198 +/- 47 ml/min), during coronary artery occlusion (left ventricular pressure, 78 +/- 12 mmHg; cardiac output, 173 +/- 39 ml/min), and after 2 h of reperfusion (left ventricular pressure, 59 +/- 17; cardiac output, 154 +/- 43 ml/min). IS in the control group was 55 +/- 10% of the area at risk. The tyrosine inhibitors had no effect on IS (genistein group, 56 +/- 13%; lavendustin A group, 49 +/- 13%; each P = 1.0 vs. control group). Desflurane preconditioning reduced IS to 40 +/- 15% (P = 0.04 vs. control group). Tyrosine kinase inhibitor administration had no effect on IS reduction (desflurane-genistein group, 44 +/- 13%; desflurane-lavendustin A group, 44 +/- 16%; each P = 1.0 vs. desflurane group).  相似文献   

107.
The incidence of inflammatory abdominal aortic aneurysm (IAAA) in a late review of the literature is estimated about 2-15% overall aortic aneurysms. In our data this type of aneurysm is 3.6 overall aortic aneurysms treated. In the majority of the cases, IAAA is juxtarenal or infrarenal. Ethiopathogenesis of IAAA till today is not certain. Recent hypothesis on IAAA attribute the same ethiopathogenesis in both atherosclerotic and inflammatory aneurysm. The interaction of genetic, environmental and infective factors should be able to determine an autoimmune inflammatory reaction of variable severity. 80% of the patients suffering from IAAA present abdominal or lumbar pain, loss of weight and increase of the RC sedimentation velocity. The IAAA's natural history goes to rupture. Entrapment of nearstanding organs totally involved in the fibrotic process is the most frequent complication. Usually there is a compression of the ureter and the duodenum with consequenced hydroureteronephrosis and bowel obstruction. Preoperative diagnosis is possible; CT scan and MRI guarantee and accuracy about 90%. Intraoperatively the external wall of IAAA appears whitish and translucent and always there are tenacious adhesion given by the avventital wounds inflammation. Confirm is given by the histological examination of the aneurysmatic wall and peravventitial tissues. Our experience and a late review of the literature concorde that surgical indication for the treatment of IAAA is the same for the atherosclerotic one. This conviction is supported by the fact that the diagnostic methodical evolution and the improvement in mininvasive surgical technique lowered perioperating morbility and mortaliy. We prefer, according with many authors, retroperitoneal approach to juxtarenal IAAA, instead of standardized transperitoneal access with xifo-pubical or transversal under costal incision. This approach offers some advantages as easier exposition of aorta, whose postero-lateral wall is hardly ever involved in inflammatory process, little duodenum's and left renal veins manipulation and low incidence of paralytic ileum and respiratory disease. Endovascular surgery hasn't in this moment any role in juxtarenal IAAA treatment because this type of aneurysm has inadequate proximal neck. In the future, probably, endovascular repair will be possible using a new type of endograft with renal legs. Often surgical treatment is inadequate to control retroperitorenal fibrosis and so surgeon has to use perioperating pharmacolocical therapy.  相似文献   
108.
The influence of a very low caloric diet (VLCD) on high density lipoproteins (HDL) is controversial. This study was designed to evaluate the influence of a VLCD on lipids and lipoproteins, especially on HDL subfractions (HDL2, HDL3) in obese women. After a 4-day period of isocaloric standard diet, 30 women at least 50% above ideal body weight were switched for 15 days on a protein-sparing modified diet providing 1.57 MJ per day. Mean body weight reduction was 5.6 +/- 0.7 kg. After the VLCD, total, very low density lipoproteins (VLDL), low density lipoproteins (LDL) and HDL cholesterol significantly decreased in all the subjects (p less than 0.01). Both HDL subfractions were depressed after the VLCD (p less than 0.01) but the reduction occurred predominantly in the HDL2 subfraction, thus inducing a decrease in the HDL2 to HDL3 cholesterol ratio (p less than 0.01). The VLCD was associated with a slight but not significant increase in the LDL to HDL cholesterol ratio. This increase was due mostly to the rise in the LDL to HDL2 cholesterol ratio (p less than 0.01). Further studies are needed to evaluate the long-term changes of HDL subfractions during weight-reducing regimens.  相似文献   
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