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61.
Quinidine gluconate 324 mg sustained release tablets (Quinaglute) was administered as a single dose to 15 healthy male subjects following an overnight fast, immediately following a high fat (HF) breakfast or immediately following a low fat (LF) breakfast. Serum samples were obtained over a 48 h period and analyzed for quinidine content using a high performance liquid chromatographic assay. Under the conditions of the study, both the rate and extent of quinidine bioavailability was significantly affected by food. The extent of bioavailability was statistically significantly greater (p less than 0.05) following both the HF and LF meals as compared to that in the fasted state. Rate of bioavailability was significantly enhanced following the LF meal as compared to that of the other two treatment groups. Although peak concentrations were greater and time to peak concentrations somewhat later following the HF meal versus those under fasting conditions, these differences were not statistically significant. In addition, the characteristics of the serum concentration-time profile (as defined by the number, magnitude, and time of occurrence of the multiple absorption maxima) was unique for each of the three treatment groups. Possible mechanisms underlying these results are explored.  相似文献   
62.
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes.  相似文献   
63.
A significant increase in urine arylsulfatase A activity (p less than 0.01) was found in patients with urothelial tumors. Arylsulfatase A activity was 1.36 +/- 1.10 U/24-h urine in control specimens, 1.90 +/- 1.66 U/24-h urine in various genitourinary tract disorders, and 3.90 +/- 1.98 U/24-h urine in transitional cell carcinoma specimens. Surgical treatment of the neoplastic patients lowered the arylsulfatase A activity found in urine to within reference values. The arylsulfatase A excreted by patients with these tumors was highly sensitive to thermal inactivation while the enzyme activity in the control urines was less affected by the heat treatment. The time course of the arylsulfatase A reaction with 4-nitrocatechol sulfate was not linear in normal individuals, while it was linear in 90% of patients with urothelial tumors. This difference in the kinetic pattern of the enzyme could be used to increase the diagnostic specificity of the determination.  相似文献   
64.
Saturated fat is known to elevate serum cholesterol, whereas soluble dietary fiber has a hypocholesterolemic effect. The objective of this study was to compare the effects of barley and wheat diets supplemented with five fat sources on lipid metabolism in chicks. In two separate experiments, broiler chicks were fed isonitrogenous diets containing 23% protein, 11.4% dietary fiber and 10% dietary fat for 17 d. Diets contained 60% either hull-less barley or red spring wheat, with either palm oil, dehydrated egg yolk, butter, tallow or corn oil. Growth, feed efficiency, plasma lipids, liver cholesterol, and fecal fat and dry matter were measured. All chicks fed wheat grew faster and had greater food efficiency than those fed barley. All barley-fed chicks had lower (P less than 0.0001) total plasma cholesterol concentration (3.1 to 4.0 mmol/L) than those fed wheat (6.0 to 11.3 mmol/L). Chicks fed palm oil with wheat had the highest total cholesterol, 11.3 mmol/L. Liver cholesterol concentration was higher (P less than 0.0001) for all wheat-fed chicks (22.8-86.4 mmol/g) compared with those fed barley (6.7 to 12.2 mmol/g). Fecal crude fat was higher (P less than 0.05) for chicks fed barley, and excreta dry matter was lower for barley-fed chicks. Results indicate that the high soluble fiber content of this barley exerts a hypocholesterolemic effect in chicks regardless of dietary fat source, possibly mediated through lowered fat absorption.  相似文献   
65.
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   
66.
67.
The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements.  相似文献   
68.
A cross-sectional study was conducted among 395 patients presenting with genital ulcers at a primary health care centre in Kigali, Rwanda. Using clinical data and the results of a rapid plasma reagin (RPR) test, we simulated the diagnostic outcome of two simple WHO flowcharts for the management of genital ulcers. These outcomes and a clinical diagnosis were then compared with the laboratory diagnosis based on culture for genital herpes and Haemophilus ducreyi and serology for syphilis. The prevalence of HIV infection was high (73%) but there was no difference between HIV-positive and HIV-negative patients in the clinical presentation and etiology of genital ulcer disease. The proportion of correctly managed chancroid and/or syphilis cases was 99% using a syndromic approach, 82.1% using a hierarchical algorithm including an RPR test, and 38.3% with a clinical diagnosis. In situations where no laboratory support is available, a simple syndromic approach is preferable to the clinical approach for the management of genital ulcer. If an RPR test can be included in the diagnostic strategy, patients with a reactive RPR test should be treated for both syphilis and chancroid infection.  相似文献   
69.
An original technique of voice rehabilitation following total laryngectomy based on the concept of a myomuscosal unit was originally described by Strome. Thirty-one cases of myomucosal shunts (MMS) are analyzed in the present report. The 14 initial cases failed because of a lack clinical and surgical experience and insufficient selection of the patients. Among the last 17 cases, 1 was lost to follow-up, 1 had an insufficient follow-up, and 2 patients refused to speak with the MMS instead of a patent shunt; 5 of the remaining patients had voices evaluated as excellent, 7 had voices interpreted as good and only 1 patient had a voice evaluated as poor. Aspiration was not a problem. Eleven patients were found to stenose their shunt, but fistula were recalibrated successfully. The MMs can be used safely in oncological surgery and only 1 of 31 deaths in our total experience was due to a local recurrence. These findings show that the MMS is a reliable procedure for voice restoration following total laryngectomy; a prosthesis is not required and there are currently no oncological limits to the procedure. However, a very close follow-up of the patients is required after surgery.  相似文献   
70.
Female Djungarian hamsters (Phodopus sungorus) have proportionately more adipose tissue in superficial depots than males of similar age and body composition. In both sexes, the proportion in superficial depots increases with increasing fatness. This species may be useful as a model for human obesity because it becomes as obese as modern humans without genetic, surgical or dietary manipulation and the sex differences in adipose tissue distribution resemble those of humans.  相似文献   
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