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111.
112.
OBJECTIVE: To compare objectively the pain associated with tubal occlusion by Silastic rings versus electrocoagulation during laparoscopic tubal ligation under local anesthesia. METHODS: Consecutive patients scheduled for laparoscopic tubal ligation under local anesthesia were randomized to Silastic rings (N = 50) or electrocoagulation (N = 52) as the method of tubal occlusion. Sterilization was performed under local anesthesia in a standard fashion. Bupivacaine 0.5% was used as the local anesthetic agent. Operative pain was measured based on intraoperative anesthesia requirements and a modified McGill pain questionnaire. This questionnaire was used to assess pain at 15 minutes, 1 hour, and 24 hours postoperatively. RESULTS: Demographics were similar for the two groups. Operative time was shorter in the Silastic-ring group (16.7 versus 21.8 minutes; P = .001), and this group also required less intraoperative anesthesia (P = .004). There were no statistical differences between the groups in self-reported pain intraoperatively or postoperatively. No patient in either group required antiemetics or pain medication in the recovery room. CONCLUSION: Silastic rings appear preferable to bipolar electrocoagulation for laparoscopic tubal sterilization under local anesthesia when long-acting local agents are used for tubal anesthesia.  相似文献   
113.
The purpose of the study was to evaluate the neuromuscular transmission defect in preeclamptic women receiving intravenous magnesium sulfate and to study the correlation of the degree of defect with serum magnesium and calcium levels. The study population included: group 1, 14 preeclamptic women receiving magnesium sulfate and undergoing induction of labor; group 2, six preeclamptic women studied in the postpartum period while receiving magnesium sulfate; and group 3, 10 normotensive women undergoing induction of labor. The neuromuscular transmission studies were performed with standard techniques before and during the administration of magnesium sulfate. During magnesium sulfate therapy patients in groups 1 and 2 showed abnormal responses characterized by an initial low-amplitude muscle action potential followed by a progressive increase in the amplitudes of the successive responses. There was significant correlation between the degree of the neuromuscular transmission defect and serum magnesium levels, serum calcium levels, and the magnesium/calcium ratio in groups 1 and 2. All studies were normal in group 3. The findings confirm the occurrence of abnormal neuromuscular transmission in preeclamptic women receiving magnesium sulfate, and the intensity of the defect correlates significantly with increased serum magnesium levels and decreased serum calcium levels.  相似文献   
114.
We describe four obese, chronically hypertensive women presenting with antepartum pulmonary edema in whom invasive hemodynamic monitoring showed elevated wedge pressure, normal to high cardiac index, and normal systemic vascular resistance. Echocardiography revealed large chambers, thick walls, and increased left ventricular mass with normal systolic but abnormal diastolic function. These findings are indicative of intrinsic volume overload occurring in the presence of impaired left ventricular relaxation, a combination resulting in high filling pressures and pulmonary congestion. Diuretic therapy is indicated in this subset of patients, who could not be recognized by the usual clinical parameters such as history and physical examination, chest x-ray, and arterial blood gas.  相似文献   
115.
With improved survival of very low birth weight infants, the incidence of bronchopulmonary dysplasia has significantly increased. Pulse oximetry appears to be an adequate alternative to transcutaneous PO2, for continuous arterial oxygen saturation (SaO2) monitoring in neonates; however, its usefulness has not been very well documented in very low birth weight infants. We studied 68 patients with birth weight less than 1,250 g; 44 neonates had respiratory distress syndrome and 24 had bronchopulmonary dysplasia. Using a Nellcor N-100 pulse oximeter, we compared transcutaneous oxygen saturation with simultaneous arterial samples analyzed for SaO2 (range 78% to 100%) using an IL 282 co-oximeter. Fetal hemoglobin was measured in 66 patients. We also evaluated the accuracy of transcutaneous PO2 in reflecting arterial PO2 in patients with bronchopulmonary dysplasia. Over a wide range of PO2, PCO2, pH, heart rate, BP, hematocrit, and fetal hemoglobin, linear regression analysis revealed a close correlation between pulse oximeter values and co-oximeter measured SaO2 in patients with acute (r = .88, Y = 19.41 + 0.79X) and chronic (r = .90, Y = 9.72 + 0.92X) disease. Regression analysis of transcutaneous v arterial PO2 in infants with bronchopulmonary dysplasia showed an r value of .78. In addition, in these patients with chronic disease, the mean difference between pulse oximeter SaO2 and co-oximeter measured SaO2 was 2.7 +/- 1.9% (SD); whereas the mean difference between transcutaneous and arterial PO2 was -14 +/- 10.7 mm Hg. Our findings indicate that pulse oximetry can be used reliably in very low birth weight infants with acute and chronic lung disease, for SaO2 values greater than 78%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
116.
STUDY OBJECTIVE: To compare postoperative nausea, emesis, analgesia, and recovery between propofol-ketamine and propofol-fentanyl in outpatient laparoscopic tubal ligations with general anesthesia. STUDY DESIGN: Prospective, randomized, blinded study. SETTING: Tertiary-care women's hospital. PATIENTS: 120 ASA physical status I and II ambulatory patients scheduled for elective laparoscopic tubal ligation. INTERVENTIONS: Patients were randomized to two groups to receive either ketamine (1-1.5 mg/kg) or fentanyl (3-5 microg/kg). MEASUREMENTS: Measured variables included total dose of ketamine, fentanyl, propofol, and operating time. Vital signs, pain visual analog scale scores (VAS), nausea VAS, presence of emesis, treatment for nausea and vomiting, pruritus, sedation, and presence of dreaming were recorded on postanesthesia care unit (PACU) admission, PACU discharge, stepdown unit admission, and hospital discharge. Results are expressed as means +/- SD or medians and analyzed using t-test, Chi-square, or Mann-Whitney (p < 0.05). MAIN RESULTS: No differences were noted with respect to propofol dose, operating times, pain or nausea VAS scores, emesis, treatment for nausea and vomiting, pruritus, and sedation on PACU admission, PACU discharge, stepdown unit admission, and hospital discharge. The ketamine group had a higher heart rate, required more pain medication, and had a higher frequency of dreaming on PACU admission than the fentanyl group. These differences became insignificant on PACU discharge. CONCLUSIONS: For outpatient laparoscopic tubal ligations with general anesthesia, propofol-ketamine does not improve postoperative nausea, emesis, analgesia or recovery compared with the propofol-fentanyl combination.  相似文献   
117.
West Nile virus (WNV) is a member of the Flaviviridae family of vector-borne pathogens. Clinical signs of WNV infection include neurologic symptoms, limb weakness, and encephalitis, which can result in paralysis or death. We report that the WNV-capsid by itself induces rapid nuclear condensation and cell death in tissue culture. Apoptosis is induced through the mitochondrial pathway resulting in caspase-9 activation and downstream caspase-3 activation. Capsid gene delivery into the striatum of mouse brain or interskeletal muscle resulted in cell death and inflammation, likely through capsid-induced apoptosis in vivo. These studies demonstrate that the capsid protein of WNV may be responsible for aspects of viral pathogenesis through induction of the apoptotic cascade.  相似文献   
118.
Arsenic is an ubiquitous element in the environment causing oxidative burst in the exposed individuals leading to tissue damage. Antioxidants have long been known to reduce the free radical-mediated oxidative stress. Therefore, the present study was designed to determine whether supplementation of alpha-tocopherol (400 mg/kg body weight) and ascorbic acid (200 mg/kg body weight) to arsenic-intoxicated rats (100 ppm in drinking water) for 30 days affords protection against the oxidative stress caused by the metalloid. The arsenic-treated rats showed elevated levels of lipid peroxide, decreased levels of non-enzymatic antioxidants and activities of enzymatic antioxidants. Administration of alpha-tocopherol and ascorbic acid to arsenic-exposed rats showed a decrease in the level of lipid peroxidation (LPO) and enhanced levels of total sulfhydryls, reduced glutathione, ascorbic acid and alpha-tocopherol and so do the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase to near normal. These findings suggest that alpha-tocopherol and ascorbic acid prevent LPO and protect the antioxidant system in arsenic-intoxicated rats.  相似文献   
119.
120.
Molecular analysis of Candida albicans isolates from individual patients often yields a single strain at multiple sites. Whether this strain-limitation is due to virulence factors favoring the invasive strain or to lack of genetic diversity in the gastrointestinal reservoir is uncertain. We elected to study C. albicans genotypes in the fecal flora among healthy volunteers and inpatients. Self-obtained stool swabs or stool samples were cultured on inhibitory mold agar. From each subject with C. albicans, nine colonies were randomly selected, individually propagated, and typed utilizing random amplified polymorphic DNA. Colonies were considered identical (all bands matched), related variants (one to three unique bands), or distinct strains (more than three unique bands). Analysis showed a single clone in 33/43 (76.7%) volunteers and 6/18 (33.3%) inpatients (P = 0.018), two to four related variants in eight (18.6%) volunteers and 10 (55.6%) inpatients, and two distinct strains in two volunteers (4.6%) and two inpatients (11.1%). Strain variation was more common in females (33.5 versus 5.6%; P = 0.04) and tended to increase with age (r = 0.245, P = 0.06). These findings illustrate that most healthy subjects harbor a single strain of C. albicans in the fecal flora. This strain may undergo genetic evolution leading to minor clonal variations. The mechanisms for strain selection, maintenance and possible evolution remain to be delineated.  相似文献   
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