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BACKGROUND: Multiple reconstructive methods have been used for the treatment of postburn scar contractures including skin grafting, geometric relaxation techniques, local flaps and free flaps. PURPOSE: In the present study, the authors evaluated efficiency of the use of rhomboid flap and double Z-plasty technique in the treatment of chronic postburn contractures. METHODS: Twelve white male with postburn scar contracture were treated using rhomboid and double Z-plasty technique. The cause of burn, duration of contracture, postoperative follow-up period, preoperative and postoperative motion lag of joints and improvement in motion were recorded. CONCLUSIONS: All operations were successful. Severe contracture lines crossing flexion folds can be released effectively by using rhomboid flap and double Z-plasty technique without distorting the specialized flexion areas and with broken scar lines which is essential to avoid from recurrence.  相似文献   
43.
BACKGROUND: There has been growing public concern on the effects of electromagnetic radiation (EMR) emitted by cellular phones on human health. Many studies have recently been published on this topic. However, possible consequences of the cellular phone usage on human sperm parameters have not been investigated adequately. METHODS: A total number of 27 males were enrolled in the study. The semen sample obtained from each participant was divided equally into two parts. One of the specimens was exposed to EMR emitted by an activated 900 MHz cellular phone, whereas the other was not. The concentration and motility of the specimens were compared to analyze the effects of EMR. Assessment of sperm movement in all specimens was performed using four criteria: (A) rapid progressive, (B) slow progressive, (C) nonprogressive, (D) no motility. RESULTS: Statistically significant changes were observed in the rapid progressive, slow progressive and no-motility categories of sperm movement. EMR exposure caused a subtle decrease in the rapid progressive and slow progressive sperm movement. It also caused an increase in the no-motility category of sperm movement. There was no statistically significant difference in the sperm concentration between two groups. CONCLUSIONS: These data suggest that EMR emitted by cellular phone influences human sperm motility. In addition to these acute adverse effects of EMR on sperm motility, long-term EMR exposure may lead to behavioral or structural changes of the male germ cell. These effects may be observed later in life, and they are to be investigated more seriously.  相似文献   
44.
Background: The purpose of the present study was to compare the cost‐effectiveness and efficacy of nebulizer recombinant human DNase (rhDNase) and hypertonic saline (HS) as monotherapy and combined treatment in neonatal atelectasis. Methods: Eighty‐seven newborns with persistent atelectasis who did not respond to traditional treatment were studied retrospectively. Group 1 did not receive nebulizer drugs; Group 2 received 7%HS; Group 3 received rhDNase; and Group 4 received both 7%HS and rhDNase. Subjects' chest X‐ray scores, partial pressure of CO2, respiratory rate, fraction of inspired oxygen (FiO2) peak inspiratory pressure, atelectasis healing rate, median duration of nebulizer treatment and costs were compared. Results: Percentages of improvement in atelectasis on Day 3 of treatment in Group 1, Group 2, Group 3 and Group 4 were 27, 70, 81 and 95%, respectively, while median duration of treatment was 8.1, 3.3, 2.9 and 2.4 days, respectively. Comparison of chest X‐ray scores, partial pressure of CO2, respiratory rate, FiO2 and peak inspiratory pressure values before and 48 h after treatment did not yield a significant difference for the control group (P > 0.05), while a marked improvement was observed in other groups for all parameters (P < 0.05). The most distinct improvement was in Group 4, followed by Group 3. Conclusions: Although both the combined treatment with HS and rhDNase and their monotherapies are effective in the treatment of persistent atelectasis in newborns receiving mechanical ventilation, their combined use produces higher efficacy. The efficacy of rhDNase is superior to monotherapy with HS. Use of these two treatments concomitantly reduces the cost. To the best of our knowledge, the present study is the first to use HS alone or in combination with rhDNase in newborn patients.  相似文献   
45.
Gitelman syndrome (GS) is an autosomal recessive disorder characterized by hypokalemia, metabolic alkalosis, hypomagnesemia and hypocalciuria. Glomerulonephritis associated with GS is rarely documented in the literature. We present an adult patient with GS whose renal biopsy revealed focal segmental glomerulosclerosis.  相似文献   
46.
The rectus abdominis muscle and musculocutaneous flaps have contributed to the efficient reconstruction of tissue defects that require a large amount of cutaneous and muscular tissue. In this article, outcomes of soft-tissue defects after reconstruction with the rectus abdominis muscle and musculocutaneous flaps were retrospectively analyzed. From August 2003 to June 2009, 25 flaps were transferred to reconstruct a wide variety of soft-tissue defects in the breast, chest wall, groin, perineal, and head and neck regions, as well as the upper and lower extremities. The rectus abdominis muscle and musculocutaneous flaps were used as part of 11 different approaches in 25 cases. There were 13 male and 12 female patients; the mean patient age was 44.2 years. The mean follow-up period was 8 months (range, 4–15 months). The overall success rate was 100%, and all flaps healed uneventfully. All reconstructive procedures were completed without any major complications. Rectus sheets were repaired primarily, and no mesh application was used. Minor complications related to transferred flaps were wound infection and dehiscence in one case, wound dehiscence in two cases, and flap lymphedema in one case. Minor complications related to the donor site were seroma in one case and wound infection and dehiscence in another case. This study presents our experience with the rectus abdominis muscle and musculocutaneous flaps in a series of 25 cases. The indications for the use of this particular flap with other flaps are discussed.  相似文献   
47.
The measurement of aortic stiffness (As) [aortic strain (S), pressure strain elastic modulus (Ep) and pressure strain normalized by diastolic pressure (Ep*)] is suggested as an excellent marker of subclinical arterial sclerosis. We aimed to investigate the presence of As and to determine the relationship between As and some risk factors in children with chronic renal failure (CRF). Twenty-six pre-dialysis (PreD) [female/male (F/M) 7/19] patients and 23 chronic peritoneal dialysis (CPD) (F/M 13/10) patients were assessed. Twenty-nine healthy children were selected as a control group (F/M 14/15). We determined anemia, abnormal calcium/phosphate metabolism, hypertension, diastolic dysfunction, increased left ventricular mass (LVM), hypertriglyceridemia, increased stiffness (Ep, Ep*), and decreased strain (S) in the CRF (PreD and CPD) group compared with the controls (P < 0.05). Presence of renal disease, LVM and usage of angiotensin-converting enzyme inhibitor (ACE-I) in all groups; female gender, duration of disease and the usage of anti-hypertensive drug therapy in CRF patients; and LVM and LVM index in healthy children were found to be independent predictors for aortic stiffness and/or strain. In conclusion, CRF is associated with significant arterial functional abnormalities in uremic children and not controlled by dialysis treatment. These results suggest that, even in young children, uremia has a profound impact on arterial function.  相似文献   
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49.
Irmak MK  Sizlan A 《Medical hypotheses》2006,66(5):1000-1007
Essential hypertension is a complex multifactorial disorder with epigenetic and environmental factors contributing to its prevalence. Epigenetic system is a genetic regulatory mechanism that allows humans to maintain extraordinarily stable patterns of gene expression over many generations. Sympathetic nervous system plays a major role in the maintenance of hypertension and the rostral ventrolateral medulla is the main source of this sympathetic activation. A possible mechanism to explain the sympathetic hyperactivity in the rostral ventrolateral medulla is an action of the area postrema. Area postrema seems to be the region where a shift of the set-point to a higher operating pressure occurs resulting in hypertension. But, how can a shift occur in the area postrema. We propose that melatonin-induced epigenetic modifications in the neurons of area postrema plays a role in this shift. Area postrema is reported to contain high levels of melatonin receptors that play a role in the epigenetic modifications in certain cells. Environmental stressors cause epigenetic modifications in the neurons of area postrema via the pineal hormone melatonin and these changes lead to a shift in the set-point to a higher operating pressure. This signal is then sent via efferent projections to key medullary sympathetic nuclei in rostral ventrolateral medulla resulting in increases in sympathetic nerve activity. This model may explain the long-term alterations in sympathetic activity in essential hypertension.  相似文献   
50.
In the present study, the in vivo micronucleus (MN) test in fish erythrocytes was used to evaluate the genotoxic potentials of water samples collected from four different sites along the Nilufer Stream which empties into the Marmara Sea on the north-west of Turkey. Nilufer Stream receives discharges of industrial and domestic wastes resulting from industrialization and urbanization activities in Bursa city. Nile tilapias (Oreochromis niloticus) were exposed to collected water samples under laboratory conditions for 3 and 6 days. Micronuclei analyses were carried out in peripheral blood erythrocytes. In addition to micronuclei, other nuclear abnormalities (NAs) such as bi-nucleated cells and binuclei with nucleoplasmic bridge and cells with blebbed, notched and lobbed nuclei, were assessed in the erythrocytes. Chemical analyses were also carried out in the water samples to assess the presence of major pollutants. MN and NA frequencies were significantly elevated in fishes exposed to water from polluted areas compared to those exposed to clean water sample. The results of this study indicate that Nilufer Stream is contaminated with potential genotoxic chemicals and the genotoxicity is possibly related with the industrial, agricultural and domestic activities.  相似文献   
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