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991.
We investigated the involvements of sympathetic and nonadrenergic nervous systems in the inhibitory reflex following bronchoconstriction in dogs. Inhalations of a 0.00125% solution of histamine and Ascaris suum antigen (3 mg protein) to the bronchial side induced reflex tracheal constriction following bronchoconstriction. An intra-arterial infusion of 5 micrograms/min of atropine to the tracheal site changed the reflex tracheal constrictions by histamine and antigen inhalations into tracheal dilatations. The reflex tracheal dilatations were abolished by the combination of intra-arterial propranolol (100 micrograms) and transections of both the bilateral superior laryngeal nerves and the spinal cord at the C1 level. The reflex tracheal constrictions induced by histamine and antigen inhalations were increased with 100 micrograms propranolol. Furthermore, the reflex tracheal constrictions were enhanced by the combination of 100 micrograms propranolol and transection of the spinal cord. These findings indicate that during the constriction of the bronchial smooth muscle, not only a reflex tracheal constriction mechanism but also one of reflex dilatation operates and that the latter reflex response may be mainly mediated by the sympathetic nerves, with partial involvement of the nonadrenergic nerves. This inhibitory reflex may attenuate asthmatic bronchoconstriction.  相似文献   
992.
Three dimensional computed tomography was performed in 150 children suffering from a bone lesion of the base of the skull and face. These lesions were either malformative, neoplastic, infectious or traumatic. 3D CT provided an essential anatomical approach to the lesions facilitating the choice of the most appropriate treatment. 3D CT is also indicated in the follow-up of these operated children, particularly of the growth of the operated bone segment and its relations with adjacent structures.  相似文献   
993.
Acquired cystic disease has been documented to complicate most forms of chronic renal damage; it has only infrequently been described in transplanted kidneys. Five patients with noncystic ESRD and chronically rejected transplants in which acquired cystic disease arose are reported. The diagnosis of acquired cystic disease was established in examination of transplant nephrectomies from four patients and a core biopsy from the fifth. The allografts were in place from 44 to 80 months; three patients were treated with hemodialysis before the diagnosis of acquired cystic disease, whereas two received peritoneal dialysis. Three of the four patients evaluated had cysts in the native kidneys. Although papillary hyperplasia of lining epithelium was evident in four specimens, only one kidney was the site of neoplasms in the form of multiple small tubular adenomas. No malignant neoplasms were noted in this study or in the few similar previous ones; however, it is possible that chronically rejected transplanted kidneys may harbor neoplasms with the same malignant potential as those in acquired cystic disease in native kidneys.  相似文献   
994.
Emulphor, a polyethoxylated vegetable oil, is now being usedwidely to incorporate volatile organic compounds (VOCs) andother lipophilic compounds into aqueous solutions for biochemical,pharmacokinetic, and toxicological studies. Previous work inthis laboratory demonstrated that 0.25% Emulphor did not alterthe kinetics or hepatotoxicity of low doses of CCl4 comparedto when the halocarbon was given to rats orally in water. Thepresent study was undertaken as there was concern that higherconcentrations of Emulphor (necessary to maintain lipophilicVOCs in stable aqueous emulsions for extended periods) mightalter the VOCs' absorption, disposition, and/or toxicity. Dosagesof 10 and 180 mg CCl4/kg bw were given, as an aqueous emulsionusing 1, 2.5, 5, or 10% Emulphor, by gavage to fasted male Sprague–Dawleyrats. Serial microsamples of blood were collected from an indwellingcannula in unanesthetized, freely moving rats at intervals of2-60 min for up to 12 hr. The samples' CCl4 content was measuredby headspace gas chromatography. Thereby, it was possible toobtain blood CCl4, concentration-versus-time profiles. Animalswere euthanized 24 hr postdosing and blood was collected formeasurement of serum enzymes as indices of hepatotoxicity. Notoxicologically significant differences in pharmacokinetic parametersas a function of Emulphor concentration were found. Similarlythe hepatotoxic potency of 10 and 180 mg/kg CCl4, as reflectedby elevation in serum enzyme activities, did not vary significantlywith the concentration of Emulphor utilized. Hence, it can beconcluded that Emulphor, in concentrations as high as 10% (equivalentto 260 mg Emulphor/kg bw) in aqueous emulsions, does not significantlyaffect the absorption, disposition, or acute hepatotoxicityof CCl4 in male Sprague–Dawley rats.  相似文献   
995.
The leading cause of postoperative morbidity in patients undergoing major head and neck surgical procedures is postoperative infection. This prospective randomized multi-institutional clinical trial was designed to compare the effectiveness of clindamycin phosphate and high-dose cefazolin sodium therapy in preventing postoperative wound sepsis in patients undergoing contaminated head and neck surgical procedures in which flap reconstruction was required. Either clindamycin phosphate (900 mg) or cefazolin sodium (2 g) therapy was instituted intravenously prior to surgery and continued every 8 hours, for a total of 24 hours. The patients received postoperative follow-up, and the wounds were graded according to the worst condition observed. One hundred cases were evaluated. Fifty-one patients received clindamycin and 49 patients received high doses of cefazolin; wound infection developed in 10 patients (19.6%) and 11 patients (21.6%), respectively. This difference was not statistically significant. The average duration of surgery was approximately 8 hours for both the infected and the noninfected groups of patients. High-dose cefazolin and clindamycin have similar efficacy when administered prophylactically under these circumstances. Reconstruction with free vascularized tissue may aid in reducing postoperative wound infection.  相似文献   
996.
Rett's syndrome(RS) is a progressive neurodegenerative disorder characterized by exclusive occurrence in females, autistic behavior, dementia, gait ataxia, loss of purposeful use of the hands with stereotypic hand movement, and seizures. Initially RS was considered to be very rare; however, recent reports suggest that the prevalence is considerably higher and occurrence is world-wide. Because the pathophysiological process remains unknown, the diagnosis of RS is based mainly on its characteristic clinical features and course. We experienced two cases of RS which, to our knowledge, are the first reported in Korea. It is quite possible that many patients with RS not yet being diagnosed in Korea.  相似文献   
997.
Selective removal of malignant cells (purging) from bone marrow (BM) is a concern in autologous BM transplantation (ABMT). Use of vincristine, etoposide, or doxorubicin for purging could be rendered ineffective by the presence of multidrug-resistant (MDR) tumor cells. To circumvent this particular problem, we investigated whether 17F9, a monoclonal IgG2b antibody directed against the cell surface product of the MDR gene, P-glycoprotein, is effective in selective removal of MDR cells from BM when used with rabbit complement (C'). Using two different cell lines we have demonstrated that 17F9 + C' selectively lyses MDR-positive cells. Three rounds of antibody + C' resulted in 96.4% +/- 3.6% kill of K562/DOX and 100% +/- 0% of CEM/VLB cells. Mixtures of malignant cells and normal BM resulted in 99.85% removal of K562/DOX and 99.91% removal of CEM/VLB clonogenic cells. This treatment did not affect normal committed precursors compared with C' alone. The addition of the cytotoxic agent etoposide (VP-16) following antibody purging results in a 4.6 log reduction of malignant cells. Furthermore, this antibody was effective when used against patients' leukemic blasts. These results suggest the use of 17F9 + C' is effective and selective for removal of MDR cells from BM before ABMT and the addition of VP-16 enhances the purging efficacy.  相似文献   
998.
999.
A Akasawa  N Koya  Y Iikura 《Arerugī》1991,40(4):428-434
Twenty-two twins' families were investigated to determine the influence of a genetic factor in the etiology of allergic diseases in children. Zygosity was confirmed by eight red cell blood types and HLA type. Eight pairs of monozygotic twins were divided by a probability of monozygosity as calculated from Essen-M?ller's method. Concordance rate of allergic disease and asthma were 88% in MZ, 86% in DZ, 75%, 73% and that of positive rate of DF-specific IgE antibody were 60% in MZ, 58% in DZ. In DZ, not sharing the same HLA haplotypes, concordance of the positive rate of DF-specific IgE antibody was 0%. Concomitant coefficiency of total serum IgE levels were 0.593 in MZ, 0.063 in DZ. These data suggested that IgE production may be influenced by genetic factors.  相似文献   
1000.
Spectral slope of vowels produced by tracheoesophageal speakers   总被引:1,自引:0,他引:1  
Spectra of vowels were analyzed to determine whether differences exist between the spectral slope of vowels produced by tracheoesophageal (TE) speakers and normal speakers and, if so, to quantify such differences. The linear predictive autocorrelation method was used to calculate smoothed spectra and the spectra were normalized with respect to a low frequency component. Comparisons between normalized spectral energy within a selected high frequency range revealed that energy within this frequency range for vowels produced by TE speakers was significantly higher than that produced by normal speakers. A least-square distance matching procedure was used to quantify speaker group differences in the spectral slope of vowels. Average spectra of vowels produced by the normal speakers could be matched to average spectra of vowels produced by the TE speakers by decreasing the spectral slope of their vowels by 2-3 dB/octave.  相似文献   
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