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991.
J Gon T Nakagawa T Tagami H Maeda T Kitano H Sakuma K Nakamura 《Kaku igaku. The Japanese journal of nuclear medicine》1991,28(1):1-10
Intrahepatic shunt ratio was calculated from the fraction of the uptake constant and the blood background, analyzing the data of 99mTc-(Sn)-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) hepatobiliary imaging by Rutland method. Shunt flow and total hepatic blood flow (THBF) were also calculated from the values for the effective hepatic blood flow (EHBF) estimated from the blood clearance technique. In 15 cases of normal volunteer, the average of the shunt ratio, shunt flow, and THBF were 18.4 +/- 5.4 (S.D.)%, 137.8 +/- 49 ml/min, and 753 +/- 83.2 ml/min, respectively. In 8 cases of chronic hepatitis, the values were 35.2 +/- 2.6%, 276 +/- 55.4 ml/min, and 794.1 +/- 119.4 ml/min, respectively. In 12 cases of liver cirrhosis, the values were 51.4 +/- 12.6%, 353.9 +/- 141.3 ml/min, and 685.6 +/- 174.8 ml/min, respectively. In cases of chronic hepatitis and liver cirrhosis, in comparison with normal cases, the values for the shunt ratio and shunt flow were significantly increased (p less than 0.001) and those for EHBF were significantly decreased (p less than 0.001), but those for THBF were not significantly altered. There was a significant inverse correlation between the shunt ratio and EHBF (r = -0.842) in all 35 cases. This method is considered to be useful for differential diagnosis, estimation of the grade of the diseases, and evaluation of pathophysiology of various diffuse liver diseases. 相似文献
992.
J S Kauer 《Trends in neurosciences》1991,14(2):79-85
Odor information appears to be encoded by activity distributed across many neurons at each level in the olfactory pathway. Thus olfactory circuits function as parallel distributed processors. New methods for observing distributed activity in such systems permit computer simulations to be constructed that are constrained by patterns of activity observed in the real system. Analysis of the system using a combination of physiological measurements and computational approaches might elucidate the principles by which odors are discriminated. 相似文献
993.
We have systematically investigated the involvement of endogenous opioids in gonadotropin secretion during primate sexual maturation by examining LH/FSH responses to gonadotropin-releasing hormone (GnRH) and changes in LH secretion during infusions of saline or naloxone, an opiate antagonist, in ten male chimpanzees between one and nine years of age. Animals were anesthetized with ketamine (10 mg/kg) and injected or infused IV with GnRH, naloxone or saline. Circulating levels of serum LH were elevated to the same extent (approximately 400%) in response to GnRH (100 micrograms) in animals 1-5 years old (juvenile) and in animals 6-9 years old (pubertal). No differences were noted between the two groups in GnRH-stimulated levels of serum FSH. During treatment with naloxone (0.14 mg/kg bolus followed by 0.2 mg/kg/h maintenance infusion for 3 h), serum LH levels in pubertal animals were significantly (p less than 0.05) elevated by as much as 95% over LH levels found during treatment with saline. Juvenile animals, on the other hand, failed to demonstrate significant increases in serum LH following naloxone at the doses tested. A strong correlation (r = .84) was found between circulating testosterone and serum LH levels during naloxone treatment. These data indicate that opioid inhibition of LH secretion can be reversed by naloxone only when puberty is reached in chimpanzees and suggest an alteration in opioid regulation of GnRH near the time of puberty. The strong correlation between testosterone levels and LH responses to naloxone suggests that steroids may participate in the maturation of opioid control of LH during puberty of nonhuman primates. 相似文献
994.
Use of sonography to evaluate carotid atherosclerosis in the elderly. The Cardiovascular Health Study. CHS Collaborative Research Group 总被引:10,自引:0,他引:10
D H O'Leary J F Polak S K Wolfson M G Bond W Bommer S Sheth B M Psaty A R Sharrett T A Manolio 《Stroke; a journal of cerebral circulation》1991,22(9):1155-1163
Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies. 相似文献
995.
J H Lipschutz R M Pascuzzi J Bognanno T Putty 《Stroke; a journal of cerebral circulation》1991,22(6):813-815
A 43-year-old woman suffered a blast-type injury to the head and neck. She subsequently developed bilateral internal carotid artery occlusion and bilateral anterior cerebral artery infarction not demonstrated by magnetic resonance imaging scan 24 hours after the explosion, but confirmed by a second scan 8 days after the explosion. In patients with blast-type injury to the head and neck who develop coma with a nonfocal neurological exam, the possibility of bilateral carotid artery occlusion and bilateral ischemic infarction should be considered. 相似文献
996.
The General Practice Research Club was established in 1969, and now has 120 members. A meeting of the club is held twice a year, at which various papers, from research ideas through to completed, published studies are presented. A survey of 40 individuals who had presented papers at meetings during the period 1984-89 showed that almost half (18) had presented papers on clinical topics. As a result of the presentation, 29 individuals had modified their research, with 11 undertaking major alterations. The meeting was rated most highly by those offering ideas and plans for research. Most individuals responded positively to the meetings, commenting that they valued peer review, found the meetings encouraging, and useful for focusing ideas. Lack of criticism and feedback was commented upon. The club has an important role to play in encouraging research by service general practitioners. 相似文献
997.
Klebsiella pneumoniae liver abscess associated with septic endophthalmitis is a rare observation. To our knowledge, only 10 cases have been reported in the international literature. We report a further case of complication occurring in an adult woman with hypothyroidism, and comment on the role of CT for the work-up. 相似文献
998.
Recent clinical drug trials have demonstrated that early intervention with zidovudine will delay disease progression in asymptomatic or minimally symptomatic HIV-infected individuals. These trials will encourage larger numbers of seropositive persons to seek access to primary care, overloading specialized clinics for AIDS and HIV care. The care of early HIV-infected individuals will need to be delivered by mainstream primary care providers. This article discusses the initiation and management of zidovudine, and chemoprophylaxis against Pneumocystis carinii pneumonia in early HIV infection. 相似文献
999.
Peter d'Abbs 《Drug and alcohol review》1989,8(1):21-29
The “restricted areas” provisions of the Northern Territory Liquor Act constitute a preventative policy aimed at reducing the effects of alcohol abuse, particularly on Aboriginal communities. Under the provisions, communities can apply to be declared “dry” or semi-restricted with respect to liquor. Since their inception in 1979, the provisions have given rise to continuing controversy. This paper addresses some of the issues associated with the controversy. Patterns of alcohol consumption on “dry”, semi-restricted and unrestricted communities are compared, and the incidence of apprehension for public drunkenness before and after restricted area declarations is examined. The paper also discusses the provisions under which vehicles implicated in acts of illicit “grog-running” are forfeited to the NT Government. It is concluded that the restricted area provisions are associated with reduced levels of alcohol consumption and apprehensions for drunkenness, and are therefore beneficial in outcome. However, it is also argued that at present the provisions are flawed in that, while some aspects serve to promote community control over alcohol consumption, other elements have the effect of undermining community control and responsibility. 相似文献
1000.