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991.
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin, and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy. At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6 per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain an adequate blood concentration of CsA without causing side effects. This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh, USA  相似文献   
992.
993.
Identification of Alcohol Abuse and Alcoholism with Biological Parameters   总被引:3,自引:0,他引:3  
The prevalence and incidence of heavy alcohol consumption are major problems which have been increasing in many countries in recent years. It is crucial for physicians to consistently identify early drinking problems as well as the various end disease states in order to minimize suffering and maximize recovery. This paper reviews the evolutionary development of clinical tools for detection of alcohol abuse. The focus is primarily on clinical/biochemical indicators of alcohol abuse, emphasizing but not limited to changes in hematological characteristics, liver enzyme activity, lipids, immune function factors, hormones, neurological factors, and some physically based tests. Use of test combinations and sophisticated statistical analysis of pattern changes in test batteries evidence increased diagnostic efficiency.  相似文献   
994.
995.
The objective of the study was to compare the clinical outcomes at the short-term follow-ups of two novel transobturator mid-urethral sling procedures – the transobturator tape (TOT) procedure and the tension-free vaginal tape (TVT)-obturator procedure. The study cohort consisted two groups of 40 women with urodynamically proven stress urinary incontinence (SUI). The patients in one group underwent the TOT procedure, performed according to Delorme (Prog Urol 11:1306–1313, 2001); those in the second group underwent the TVT-obturator operation, performed according to de Leval (Eur Urol 44:724–730, 2003). Intra-operative diagnostic cystoscopy was not performed with either the TVT-obturator or the TOT procedures. The average follow-up was 12 months. The two patient groups were similar in terms of demographic and therapeutic criteria, except for patient age, which was significantly younger in the TVT-obturator group. Previously reported TVT-related operative complications, such as bladder penetration, intra-operative bleeding, field infection and post-operative pelvic floor relaxation, were not observed in patients of either group. Bowel and urethral injuries were also not recorded. The therapeutic failure rates were 10% for the TOT procedure and 5% for the TVT-obturator procedure. Urinary frequency and urgency post-operatively were reported in 25% of the TOT patients and 19% of the TVT-obturator patients, pelvic or vaginal pain affected 10% of the TOT and 5% of the TVT-obturator patients, while post-operative voiding difficulty was experienced by 12.5% of the TOT and 7.5% of the TVT-obturator patients. None of the above-mentioned differences between the two patient groups were of statistical significance. The TVT-obturator and TOT procedures, both minimally invasive, novel, mid-urethral sling procedures, seem to be safe, easy-to-perform and effective in treating female SUI. The patients of both study groups suffered less intra- and post-operative surgical complications than previously been reported in connection with the TVT operation. The TVT-obturator patients had fewer therapeutic failures, less post-operative urinary frequency and urgency, less pelvic pain and less voiding difficulty. All of these findings, however, had no statistical significance; consequently, long-term comparative data collection will be required before solid conclusions can be drawn on the superiority of either of these two operative techniques.  相似文献   
996.
997.
The ratio of PaO2 to FiO2 was often low (300 or less) in four patients with complications of hyperosmolar hyperglycemic non-ketotic diabetic coma (HHNKDC) following open heart surgery. Four of our patients had poor oxygenation and subsequent spontaneous recovery from in the immediate post-operative period, although HHNKDC occurred only in one during this period. In the 3 others, poor oxygenation without accompanying HHNKDC lasted for 1–6 days and HHNKDC developed about 2 weeks after open heart surgery at time when poor oxygenation reoccurred. If a working diagnosis of congestive heart failure was made only on the basis of the most common probability, and the fluid supply was restricted, HHNKDC would readily occur or be aggravated by the dehydration iatrogenically produced. It is thus concluded that HHNKDC should be included in diagnoses for pulmonary dysfunction.  相似文献   
998.
999.
1000.
Andrew G. Herzog  MD  MSc 《Headache》2007,47(S2):S68-S78
Migraine is 3 times more common in postpubertal women than in men. Migraine is frequently exacerbated perimenstrually and commonly occurs exclusively at that time. It is often benefited by pregnancy and menopause. Estrogen withdrawal has been implicated as a mechanism for triggering migraines. The mechanism, however, is not well understood. Reproductive steroids have neuroactive properties that can modulate neuronal morphology and physiology. Increasing evidence suggests that circulating reproductive steroid levels regulate the balance of neuroexcitatory and neuroinhibitory activities in some brain regions by influencing synaptic plasticity. Estrogen has neuroexcitatory, whereas progesterone has neuroinhibitory, effects in most preclinical and clinical models. Several neurotransmitter systems that are implicated in migraine vary with reproductive steroid levels during the reproductive cycle. Estrogen stabilization may provide effective treatment in susceptible women, especially for catamenially exacerbated migraine.  相似文献   
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