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991.
BACKGROUND: Resuscitation with racemic lactated Ringer's solution induces cellular apoptosis. This study was conducted to determine if the elimination of D-lactate isomer would attenuate apoptosis in the liver, and to investigate the possible mechanisms. STUDY DESIGN: Sprague Dawley rats (n=30, 5 per group) were subjected to modified volume-controlled hemorrhage and randomized to the following groups: no hemorrhage (sham); no resuscitation (NR); resuscitation with racemic lactated Ringer's (DL-LR); L-isomer LR (L-LR); ketone (beta-hydroxybuturate) Ringer's (KR); or pyruvate Ringer's (PR). Animals were sacrificed 2 hours later and expressions of proapoptotic proteins (BAD), antiapoptotic (bcl-2) proteins, and poly-ADP ribose polymerase (PARP) cleavage in liver were analyzed by Western blotting. Contribution of the phosphatidylinositol 3-kinase/serine/threonine kinase (PI3k/Akt) pathway was assessed by measuring total and phosphorylated PI3K, Akt, BAD, and endothelial nitric oxide synthase (eNOS) proteins. The terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay was used to detect the apoptotic cells. Liver ATP levels were measured using a luciferase reaction assay. RESULTS: Hemorrhage significantly decreased the hepatic ATP level and resuscitation improved it, but it returned to normal only in the L-isomer lactated Ringer's and ketone Ringer's groups. Expression of proapoptotic proteins was significantly lower in the pyruvate Ringer's and ketone Ringer's groups; L-isomer lactated Ringer's and pyruvate Ringer's resuscitation significantly increased bcl-2 expression. Poly-ADP ribose polymerase fragmentation and total number of apoptotic cells were significantly increased in the racemic lactated Ringer's group. There was no significant induction of Akt activity or changes in phosphorylated BAD, Akt, or eNOS levels. CONCLUSIONS: Resuscitation with racemic lactated Ringer's induces hepatic apoptosis, which is decreased if the D-isomer of lactate is eliminated. Apoptosis is reduced even more when lactate is substituted with beta-hydroxybutyrate or pyruvate. The beneficial effects are not through improvements in the energy status or activation of the PI3K/Akt pathway.  相似文献   
992.
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   
993.
A patient who presented with priapism after ingestion of alfuzosin is described. He presented with recurrent priapism, which was relieved temporarily after physical exercise. It did not subside with pharmacologic management and was managed surgically using Winter's procedure. It remained quiescent for a short period, only to reappear later. After additional conservative management, he was well enough to be discharged. At 12 months of follow-up, he was well, had no penile fibrosis, was able to have unaided intercourse, and had moderately bothersome lower urinary tract symptoms. This case illustrates that no therapeutic drug is without side effects and emphasizes the need to warn patients appropriately.  相似文献   
994.
We are presenting a 5-year-old boy with a traumatic high-flow priapism developed after a straddle injury and successfully treated by compression and simultaneous monitoring with a duplex ultrasound probe. We believe that this may be an alternative method against conventional treatment modalities including conservative follow-up, sympathomimetic drug administration, percutaneous embolization of the fistula, and surgical ligation.  相似文献   
995.
Rapid induction of a profound hypothermic state (suspended animation) can maintain viability of key organs during repair of lethal injuries. Conventional cardiopulmonary bypass equipment (roller pump) used to induce and reverse hypothermia is expensive, bulky, requires standard electricity, and is not transportable. Development of a small, portable, battery operated, disposable, pump can logistically facilitate induction and maintenance of hypothermia. In this experiment, a portable prototype pump was tested and its performance was compared with the regular roller pump in a swine model of lethal vascular injuries. METHODS: Uncontrolled hemorrhage was induced in 16 swine (80-120 lbs) by creating an iliac artery and vein injury (nonlethal). After 30 minutes of pulseless shock, the descending thoracic aorta was lacerated (lethal injury). Through a left thoracotomy approach, a catheter was placed in the aorta and cold organ preservation solution was infused to rapidly (2 degrees C/min) induce hypothermia (10 degrees C) for 60 minutes. The performance of the prototype pump was initially tested in a nonsurvival experiment (four animals). Then, 12 animals were cooled either with (n = 6/group) (1) conventional roller pump or (2) small prototype pump. The injuries were repaired during hypothermic arrest and the animals were re-warmed (0.5 degrees C/min). Whole blood was infused during resuscitation on cardiopulmonary bypass. Surviving animals were closely monitored for 3 weeks for postoperative complications, neurologic deficits, and organ dysfunction. RESULTS: The flow rates and the time needed to induce and reverse profound hypothermia were no different between the prototype and the conventional roller pumps. Three-week survival rates were 83% in both groups. Only a transient increase in liver enzymes, and markers of cellular injury (creatine kinase, lactate dehydrogenase) was noted (no meaningful difference between groups), with no long-term organ dysfunction. CONCLUSIONS: In this large animal model of lethal vascular injuries, a portable, battery operated, disposable, rotary pump performed as well as the conventional roller pump. The logistical advantages of this system make it an attractive choice for inducing hypothermia in emergency departments and austere settings, and for maintaining hypothermia during transport.  相似文献   
996.
Routine repeat head CT for minimal head injury is unnecessary   总被引:2,自引:0,他引:2  
BACKGROUND: Patients with MHI and a positive head computed tomography (CT) scan frequently have a routine repeat head CT (RRHCT) to identify possible evolution of the head injury requiring intervention. RRHCT is ordered based on the premise that significant injury progression may take place in the absence of clinical deterioration. METHODS: In a Level I urban trauma center with a policy of RRHCT, we reviewed the records of 692 consecutive trauma patients with Glasgow Coma Scale scores of 13-15 and a head CT (October 2004 through October 2005). The need for medical or surgical neurologic intervention after RRHCT was recorded. Patients with a worse and unchanged RRHCT were compared, and independent predictors of a worse RRHCT were identified by stepwise logistic regression. RESULTS: There were 179 patients with MHI and RRHCT ordered. Of them, 37 (21%) showed signs of injury evolution on RRHCT and 7 (4%) required intervention. All 7 had clinical deterioration preceding RRHCT. In no patient without clinical deterioration did RRHCT prompt a change in management. A Glasgow Coma Scale score less than 15 (13 or 14), age higher than 65 years, multiple traumatic lesions found on first head CT, and interval shorter than 90 minutes from arrival to first head CT predicted independently a worse RRHCT. CONCLUSIONS: RRHCT is unnecessary in patients with MHI. Clinical examination identifies accurately the few who will show significant evolution and require intervention.  相似文献   
997.
INTRODUCTION: The liver is critical in multiple processes, including the clearance of endogenous compounds, the synthesis of macromolecules, and organ-specific biotransformation processes. Therefore, the liver's regenerating capacity is of vital importance. Multiple pathways are activated in the complex process that leads to hepatic regeneration. In the present study, we aimed to evaluate the effect of proton pump inhibitors omeprozole, lansoprazole, and pantoprazole on hepatic regeneration following partial hepatectomy. MATERIALS AND METHODS: Four groups were formed with 32 rats in each. Partial liver resections were performed for all animals. Omeprazole (71.4 microg/day), lansoprazole (107 microg/day), pantoprazole (143 microg/day) and placebo (0.5 cm(3)) were administered to the groups respectively. A quarter of the rats in each group were sacrificed on the 1st postoperative day. The rest were sacrificed on the 3rd, 5th and 7th postoperative days. The remnant regenerating liver mass was removed and weighed, and Ki-67 monoclonal antibody levels were measured. RESULTS: There was no statistical difference between the four groups on the first day in evaluating the weight of the liver mass (p = 0.09) and Ki-67 (p = 0.268) levels. Only the omeprazole group showed a difference; the Ki-67 level was lower in the omeprazole group on the 3rd (p = 0.003, p = 0.0001, p = 0.003), 5th (p = 0.017, p = 0.001, p = 0.0001) and 7th (p = 0.0001) days compared to the other groups. Also the weight of the remnant liver mass was lower in the omeprazole group on the 3rd, 5th and 7th (p = 0.0001) days. CONCLUSION: We figured out that lansoprazole and pantoprazole have no effects on liver regeneration, whereas omeprazole showed a negative effect on hepatic regeneration.  相似文献   
998.
BACKGROUND/AIMS: Ischemia-reperfusion injury is a serious clinical situation which can cause serious morbidity and mortality. An experimental renal ischemia-reperfusion injury model was designed to evaluate the role of glyceryl trinitrate (GTN) on renal function and histology. METHODS: 50 Wistar albino rats were used in our study. Five groups were formed: (1) sham-control group; (2) acute renal ischemia (ARI) group with placebo (0.9% NaCl) infusion; (3) GTN infusion with a 75 microg/kg/min dose prior to ARI was administered; (4) GTN infusion with a 150 microg/kg/min dose prior to ARI was given, and finally (5) 150 microg/kg/min GTN infusion after the ARI period was applied. Serum BUN and creatinine levels were measured for evaluation of renal function. T(max-sec), glomerular filtration rate (GFR), and T(max-min) results following a (99m)Tc-DTPA diuretic renal scintigraphy were used. Histological examination was performed on nephrectomy specimens. RESULTS: Groups 2 and 5 showed higher BUN, creatinine, and lower GFR values than the other groups (p = 0.0001). There was no difference in BUN, creatinine, and GFR levels between groups 2 and 5 (p = 0.971, p = 0.739, p = 0.393). Also the T(max-sec) values were higher in groups 2 and 5 compared with the other groups (p = 0.0001). The presence of tubular necrosis was different between groups and was higher in groups 2 and 5 (p = 0.002). CONCLUSION: The application of GTN, a nitric oxide donor, has caused significant improvement in renal function when applied prior to an experimentally designed renal ischemia-reperfusion model. But administration of GTN had no effect after occurrence of ischemia.  相似文献   
999.
OBJECTIVE: To correlate ovarian endometrioma diameter with the extent of pelvic adhesions. STUDY DESIGN: Forty women with unilateral ovarian cysts thought to be endometriomas were prospectively recruited. The interventions were transvaginal ultrasound to measure the size of the ovarian endometrioma and a laparoscopic surgical procedure, including detailed pelvic assessment. Main outcome measures were pelvic adhesion scores using the American Fertility Society revised classification of endometriosis. RESULTS: Thirty-two women met the inclusion criteria. Twelve had an endometrioma < 3 cm in diameter; 12, 3-5 cm; and 8, > 5 cm. Adhesion scores from various anatomic areas did not differ across these 3 groups. No correlation between the size of the endometrioma and associated pelvic adhesions was found using multiple regression analysis. CONCLUSION: The size of an endometrioma measured by transvaginal ultrasound does not correlate with the extent of adhesive disease. Small (< 3 cm) endometriomas may be associated with a considerable degree of pelvic adhesions.  相似文献   
1000.
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