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991.
J T Johnson R L Wagner D E Schuller J Gluckman J Y Suen N L Snyderman 《Archives of otolaryngology--head & neck surgery》1992,118(5):488-490
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
992.
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
993.
M Aihara Y Aihara G Schmidt-Wolf I Schmidt-Wolf B I Sikic K G Blume N J Chao 《Blood》1991,77(9):2079-2084
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
994.
995.
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
996.
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
997.
Y Herabutya N Israngura Na Ayudthaya 《International journal of gynaecology and obstetrics》1991,34(2):169-173
Nineteen cases of mid-trimester pregnancy were terminated using prostaglandin E2 gel applied intracervically. In this prospective study, 42% were primipara with gestational age at the time of abortion between 16 and 28 weeks. The induction to abortion time was 19.65 +/- 10.37 h with a success rate of 89%. The average number of applications was 1.8 times (range 1-3 times) and the average dosage of prostaglandin required was 5.5 mg (range 3-9 mg). The complications were minimal except retained placenta in 42% of cases. Prostaglandin E2 in form of gel applied intracervically is an effective alternative to the commonly used hypertonic saline or, more recently, to prostaglandin analogues for termination of pregnancy in the second trimester. 相似文献
998.
K Takayasu Y Muramatsu N Moriyama S Yamazaki T Takayama S Hirohashi Y Shimamura A Takahashi 《Journal of computer assisted tomography》1992,16(2):212-215
To differentiate focal nodular hyperplasia (FNH) from other hepatic tumors, especially hepatocellular carcinoma, we evaluated the hemodynamics of histologically proved FNH in three patients, two by arterial angio-CT and one by microangiography of the resected specimen. These studies demonstrated the centrifugal blood supply of FNH (early filling of central tumor vessels radiating to periphery, and lobulated tumor stains with central low density area in the late phase), which could not be demonstrated by dynamic CT or hepatic angiography. Arterial angio-CT is useful as a further study, when differential diagnosis of FNH is uncertain by other imaging techniques. 相似文献
999.
1000.
Polyester-crystic cast was observed to reach the peritubular capillary plexus following injection in sheep kidneys. Microvascular structures in this region are also reported in this study. Glomeruli were found to vary in size and shape. Diameters of afferent arterioles were larger than those of efferent arterioles. The glomerulus is supplied by more than one afferent arteriole, and in some regions, the blood in afferent arterioles joins collateral circulation via the intercapillary plexus. Morphological properties at the end of the peritubular capillary plexus were found to be remarkably significant. 相似文献