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BACKGROUND: We investigated the effect of alpha-lipoic acid (LA) on reperfusion injury in a rat ovarian torsion-detorsion model. The changes in tissue and plasma levels of malondialdehyde (MDA), end-product of lipid peroxidation, superoxide dismutase (SOD), xanthine oxidase (XO) and nitric oxide (NO), were determined. Ovarian histopathological findings were scored and compared among groups. MATERIALS AND METHODS: Thirty-two female Sprague-Dawley rats were divided into four groups. Sham operation was performed in group I; in group II only ovarian torsion was performed. Group III received intraperitoneal injections of saline, and group IV received LA via intraperitoneal injections (LA group: aqueous solution at 36 mg/kg of body weight per day, saline group: equal volume of saline) 21, nine, and one hour before torsion of the ovary. Rats in the torsion group were killed after 360 degrees clockwise adnexial torsion for three hours, and ovaries were harvested. After three hours of adnexial detorsion, the rats in saline group and LA group were killed and adnexa were surgically removed. RESULTS: Ovarian tissue damage scores were significantly different among groups and were seen to correlate with tissue MDA levels. Ovarian tissue and serum MDA, NO and serum XO levels in the group III were significantly higher than those of the groups I and IV (P<0.05). The serum levels of SOD in the group III were significantly lower than those of the groups I and IV (P<0.05). CONCLUSION: These results suggest that LA pretreatment has beneficial effects in the prevention of ischaemia-reperfusion injury of the ovaries.  相似文献   
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Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
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STUDY OBJECTIVE: To compare hemodynamics, recovery profiles, early postoperative pain control and costs of total intravenous anesthesia (TIVA) with propofol and remifentanil and propofol and alfentanil. DESIGN: Randomized, double-blind study. SETTING: University hospital. PATIENTS: 40 ASA physical status I and II adult patients scheduled for lumbar discectomy. INTERVENTIONS: Patients were randomly assigned to receive either remifentanil-propofol or alfentanil-propofol. Anesthesia was induced with remifentanil 1 microg kg(-1) or alfentanil 20 microg kg(-1) with propofol 2 mg kg(-1), and maintained with infusions of propofol 150 to 100 microg kg(-1)min(-1) and either remifentanil 0.1 microg kg(-1) min(-1) or alfentanil 0.5 microg kg(-1) min(-1). MEASUREMENTS: Hemodynamic parameters (heart rate and mean arterial pressure), times to awakening, and tracheal extubation were recorded. In the postanesthesia care unit, pain level, frequency of analgesic demand, frequency of postoperative nausea and vomiting (PONV), partial oxygen saturation (SpO2), and respiratory rates were noted. Drug dosages and costs of each technique were determined. MAIN RESULTS: The mean arterial pressure significantly decreased compared to baseline values 1 minute after induction (p < 0.05) in both groups, and it significantly decreased at 5, 15, and 30 minutes perioperatively in the remifentanil group compared to the alfentanil group (p < 0.05). Time of extubation, spontaneous eye opening, and response to verbal command were similar in both groups. Visual analog scale pain scores at 30 minutes and 60 minutes were significantly lower in the alfentanil group than remifentanil group (p < 0.05). At 15, 30, and 60 minutes after terminating the operation oxygen saturation and respiratory rate were significantly higher (p < 0.05) and analgesics were required sooner in the remifentanil group than the alfentanil group (p < 0.05). The frequency of PONV was similar in both groups. The remifentanil-propofol anesthesia was found to be slightly more expensive as compared to the alfentanil based TIVA (33.41 +/- 4.53 vs. 29.97 +/- 4.1 USD) (p < 0.05). CONCLUSIONS: Both remifentanil and alfentanil provided a reasonably rapid and reliable recovery. The remifentanil-based TIVA was associated with high intraoperative cost and early postoperative pain, but it allowed a more rapid respiratory recovery.  相似文献   
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Multidisciplinary management of breast cancer concurrent with pregnancy.   总被引:3,自引:0,他引:3  
The management of PABC is very difficult. The incidence of PABC is low, but may be increasing because of the number of women who are becoming pregnant at a later age. More investigation is needed to understand whether the biology of PABC is different from that of breast cancer in nonpregnant women. One exciting area of further research is the potential relationship between mutations in known breast cancer susceptibility genes and breast cancer development during pregnancy. Diagnosis or PABC remains challenging because of the anatomic and physiologic changes that occur in the breast during pregnancy. Understanding the generic influences on PABC may help physicians in diagnosing this disease earlier, and understanding the tumor-receptor characteristics of PABC can help physicians deliver effective treatment. The various modalities available for treatment of PABC and their risks and benefits must be discussed openly with patients and their families. Abortion is not usually recommended. Modified radical mastectomy is the recommended treatment for PABC diagnosed during the first trimester. Neoadjuvant or adjuvant chemotherapy can be given with minimal risks to the fetus during the second or third trimester. Radiation therapy is contraindicated during pregnancy because of the potential for injury to the fetus. Breast conservation therapy, with radiation treatments given after delivery or after neoadjuvant chemotherapy, is an option for women with PABC diagnosed late in pregnancy. Once the appropriate treatment modality is chosen, its implementation must not be delayed because of the pregnancy. Most of the literature shows that women with PABC have the same survival stage for stage as nonpregnant women with breast cancer. But some studies suggest that the prognosis is worse for patients who present with advanced-stage PABC. Finally, recurrence and survival in most patients previously treated for breast cancer do not appear to be adversely affected by subsequent pregnancy. Above all, the patient with breast cancer diagnosed during pregnancy is best served by early and continued involvement of a multidisciplinary cancer treatment team.  相似文献   
28.
The treatment of unstable trochanteric femoral fractures is still challenging, and the proximal femoral nails are becoming more commonly used. The proximal femoral nailing is usually performed on a fracture table under traction which is associated with some possible complications. In our study, we tried to present the results of proximal nailing surgery performed in the lateral decubitus position and manual traction on a radiolucent table without the fracture table traction.  相似文献   
29.
Background

The negative impact of anastomotic leakage on cancer-specific survival and recurrence patterns has been recognized in colorectal cancer. In pancreatic cancer, pancreatic fistula (PF) is a serious morbidity, but its negative effect on long-term outcome remains to be elucidated. The aim of this study was to determine the impact of PF on pancreatic cancer recurrence.

Methods

The medical records of 184 patients with curative pancreatectomy for pancreatic cancer were reviewed. PF was scored on the basis of the International Study Group of Pancreatic Fistula classification. Overall and disease-free survivals and recurrence patterns were analyzed. Grade A PF was excluded because the negative effects can be negligible.

Results

PF occurred in 51 of the 184 patients (27.7%). The mortality related to PF was 0.5% (1 of 184). PF was an independent risk factor for peritoneal recurrence (hazard ratio 3.974; 95% confidence interval 1.345–11.737; P = 0.013). According to the analysis of disease-free survival in patients with peritoneal recurrence, time to recurrence was shorter and the survival rate was worse in patients with PF than in those without PF (5.6 vs. 8.2 months; 6-month survival, 40 vs. 71%; 1-year survival, 7 vs. 19%; P = 0.053). PF was an independent prognostic factor after multivariate analysis (hazard ratio 3.257; 95% confidence interval 1.201–8.828; P = 0.020).

Conclusions

PF was statistically significantly related to peritoneal recurrence, and patients with PF developed peritoneal recurrence earlier than those without PF. With regard to the development of peritoneal recurrence, PF may be considered to be a negative prognostic factor.

  相似文献   
30.
BACKGROUND AND PURPOSE: We investigated the impact of percutaneous renal procedures on estimated glomerular filtration rate (GFR) of patients with chronic kidney disease (CKD). PATIENTS AND METHODS: The GFRs of adult patients were calculated using the Modification of Diet in Renal Disease formula, and the patients were staged according to the Kidney Disease Outcome Quality Initiative CKD classification system. The study included 185 patients with preoperative GFR values less than 60 mL/min/1.73 m(2). The impact of percutaneous nephrolithotomy (PCNL) on GFR was analyzed by comparing the preoperative GFR with the GFR before discharge and at postoperative month 3. RESULTS: Patients with CKD had a significant increase in the GFR after the procedure. In postoperative month 3, the mean GFR was more than 60 mL/min/1.73 m(2) in 25% of the patients with CKD and less than 60 mL/min/1.73 m(2) in 75%. While all patients with stage 5 CKD improved to better stages, some other patients' conditions declined to stage 5 from better stages at the end of postoperative month 3. No patient needed dialysis. The presence of urinary tract infections tended to affect GFR negatively. CONCLUSION: Estimated GFR, as a better indicator of renal function, is significantly affected by the PCNL procedure. While significant improvement was observed in late-stage patients with CKD, unexpected deterioration could occur in patients at earlier stages.  相似文献   
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