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901.
902.
903.
Peroperative tinidazole and placebo treatment were compared with respect to incidence of postoperative infections in a double blind investigation on patients admitted for elective bowel surgery. Patients in the tinidazole group had a significantly reduced postoperative infection rate, compared with the placebo group (7.4% and 46%, respectively). Complications in general were fewer in the tinidazole group and costs for antibiotic treatment decreased. All tinidazole-treated patients had clinically effective blood concentrations of the drug at the time of the operation. In contrast with the placebo-treated subjects, the individuals who developed postoperative wound infections from the tinidazole group had no growth of anaerobic bacteria and no antibody response to Bacteroides sp. The use of tinidazole may therefore be recommended for the prevention of postoperative anaerobic infections in patients undergoing bowel surgery.  相似文献   
904.
The dystrophic forms of epidermolysis bullosa (DEB) are due to mutations in the type VII collagen gene (COL7A1). In dominant DEB, a characteristic genetic lesion is a glycine substitution mutation within the collagenous domain of the protein. In this study, we have examined the molecular basis of six new families in which the proband has clinical features and/or ultrastructural findings consistent with DEB. The results revealed a glycine substitution mutation in all six families, four of which are novel and previously unpublished. In three families with clinically unaffected parents, de novo mutations G2043R and G2040V were found. These results emphasize the predominance of glycine substitution mutations in dominant DEB, and indicate that in some cases the phenotype is due to de novo dominant mutations.  相似文献   
905.
PURPOSE: To assess the safety and effectiveness of an immunotoxin, MDX-RA, designed to inhibit posterior capsule opacification (PCO). SETTING: Eleven private practices in the United States. METHODS: This study comprised 63 eyes of 63 patients having extracapsular cataract extraction by phacoemulsification; these patients were enrolled in a Phase I/II clinical investigation of the immunotoxin MDX-RA. At the close of surgery, 21 patients were treated with placebo, 23 patients with 50 units of the immunotoxin, and 19 patients with 175 units of the immunotoxin as an aqueous solution. The patients were monitored for 24 months after primary cataract surgery using external eye and slitlamp examinations, visual acuity assessment, ophthalmoscopy, pachymetry, tonometry, endothelial cell counts, and lens capsule photography. Posterior capsule opacification, recorded on lens capsule photographs, was graded independently by a committee of 3 cataract surgeons. The incidence of neodymium:YAG (Nd:YAG) capsulotomy was projected from the opacification results. RESULTS: The immunotoxin, at the 50 unit dose, was well tolerated and effective in inhibiting PCO. At the 175 unit dose, there was a trend toward increased postoperative inflammation that was transient with no residua. From 6 to 24 months postoperatively, the 50 unit dose significantly inhibited PCO compared with the placebo (P < .05). This significant reduction in PCO translated into a significantly lower projected need for Nd:YAG capsulotomy in the 50 unit than the placebo group (P < .004). About 60% in the placebo group and 4% in the 50 unit group were projected to need an Nd:YAG capsulotomy by 3 years postoperatively. CONCLUSION: The immunotoxin was well tolerated and was effective in reducing PCO for up to 24 months after cataract surgery. Although these preliminary results are encouraging, a larger study is underway to determine whether the reduction in PCO by the immunotoxin decreases the need for Nd:YAG capsulotomy.  相似文献   
906.
Fluorescence quenching was used to study the site-specific binding of the Escherichia coli regulatory protein TyrR to a fluoresceinated oligonucleotide (9F30A/30B) containing a TyrR binding site. The equilibrium constant for the interaction (KL) was measured as a function of temperature and salt concentration in the presence and absence of ATPgammaS, a specific ligand for TyrR. Fluorescence titrations yielded a KL value of 1.20 x 10(7) M-1 at 20 degrees C, which was independent of the acceptor (9F30A/30B) concentration in the range 5-500 nM, indicating that the system exhibits true equilibrium binding. Clarke and Glew analysis of the temperature dependence of binding revealed a linear dependence of R ln KL on temperature in the absence of ATPgammaS. The thermodynamic parameters obtained at 20 degrees C (theta) were = -35.73 kJ mol-1, = 57.41 kJ mol-1, and = 93.14 kJ mol-1. Saturating levels of ATPgammaS (200 microM) strengthened binding at all temperatures and resulted in a nonlinear dependence of Rln KL on temperature. The thermodynamic parameters characterizing binding under these conditions were = -39.32 kJ mol-1, = 37.16 kJ mol-1, = 76.40 kJ mol-1, and = -1.03 kJ mol-1 K-1. Several conclusions were drawn from these data. First, binding is entropically driven at 20 degrees C in both the presence and absence of ATPgammaS. This can partly be accounted for by counterions released from the DNA upon TyrR binding; in the absence of ATPgammaS and divalent cations, the TyrR-9F30A/30B interaction results in the release of two to three potassium ions. Second, the more favorable value, and hence tighter binding observed in the presence of ATPgammaS, is primarily due to a decrease in (-20.3 kJ mol-1), which overcomes an unfavorable decrease in (-16.7 kJ mol-1). Third, the negative value obtained in the presence of ATPgammaS indicates that the binding of ATPgammaS favors a conformational change in TyrR upon binding to 9F30A/30B, yielding a more stable complex.  相似文献   
907.
908.
A previously well 24-year-old man complained of persistent epigastric pain after a session of intensive muscle building exercise especially of the abdominal muscles. The abdomen was diffusely tender without guarding. There was an increased concentration of bilirubin (64.7 mumol/l), GOT (117 U/l), GPT (529 U/l) and alkaline phosphatase (150 U/l). Ultrasound examination showed a widening of the choledochal duct to 11 mm without signs of gallstones. Endoscopic retrograde cholangiography additionally revealed contrast-medium extravasation from the left hepatic duct. Computed tomography, performed immediately afterwards, confirmed the extravasation, while liver and pancreas were unremarkable. Laparoscopy revealed a 5 mm tear in the left hepatic duct, close to the hepatic duct bifurcation with bile effusion into the peritoneal cavity. The latter was rinsed endoscopically with Ringer's solution and drains were placed in the omental bursa and subhepatically in the region of the bile leak. To relax the sphincter Oddi glycerol trinitrate was administered postoperatively, for the first five days 72 mg/24 h intravenously, then for nine days twice daily 20 mg by month. No more bile drained as early as the second postoperative day and the patient was free of symptoms 2 weeks later.  相似文献   
909.
OBJECTIVE: To determine the effectiveness of botulinum toxin injections for the management of hyperfunctional facial lines in patients with dystonia. DESIGN: Twenty-six patients were included in the study: 24 patients had dystonic movement of the face as either a primary or secondary component, and two patients were treated for purely hyperfunctional lines. Botulinum toxin type A was injected via a monopolar hollow-bore Teflon-coated electromyography needle into the facial muscles associated with the hyperfunctional lines. Doses were divided into 1.25- to 10-U aliquots. Qualitative assessments by the patient and physician were made before injection and 2 to 3 weeks after injection. PATIENTS: Twenty-six patients (two male and 24 female) with hyperfunctional lines were included. The ages were from 32 to 84 years with an average age of 59 years. Twenty had dystonia, four had hemifacial spasm, and two had pure hyperfunction without neuromuscular disease. RESULTS: All of the patients had an effect of toxin within the first 24 to 72 hours. All of the patients experienced benefit from the toxin injections with partial or total resolution of painful contractions or unsightly hyperfunctional lines and spasms. The effects of the injection lasted 3 to 6 months. No systemic side effects were noted. Adverse effects included mild, temporary eyelid or lip weakness. CONCLUSION: Based on this initial pilot study, botulinum toxin may be an important new option for the treatment of patients with hyperfunctional facial lines.  相似文献   
910.
Following bilateral lesions to the posterior medial hypothalamus (homologue of the mammalian ventromedial nucleus), adult male ring doves regain full courtship behavior and the ability to stimulate female egg-laying when housed continuously with females. Males with PMH lesions housed singly and only tested periodically with females continue to show deficits in courtship. These findings suggest that the social environment present in adulthood itself can directly influence recovery from brain lesions. They also demonstrate the importance of PMH in the mediation of male ring dove courtship behavior.  相似文献   
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