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991.
Shunichi Takaya MD Shunzaburo Iwatsuki Takashi Noguchi Hisaaki Koie Iman Zaghloul Raman Venkataramanan Thomas E. Starzl 《Surgery today》1989,19(1):49-56
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.
Ronald R. Watson PhD Mary E. Mohs MS RD Cteamond Eskelson PhD Richard E. Samptiner MD Barbara Hartmann PhD 《Alcoholism, clinical and experimental research》1986,10(4):364-385
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.
996.
Shuji Seki MD 《Surgery today》1987,17(2):123-129
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
997.
998.
999.
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
1000.
Michael S. Runyon MD Peter B. Richman MD Jeffrey A. Kline MD 《Academic emergency medicine》2007,14(1):53-57
Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two‐page paper survey including 15 multiple‐choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty‐seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE. 相似文献