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31.
Unilateral intranigral injections of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) and MPP+ (1-methyl-4-phenylpyridine) were given to young rats and unilateral intranigral injections of MPTP were given to old rats. MPTP in old rats and MPP+ in young rats induced ipsiversive circling for at least one week after injection and contraversive circling after the systemic administration of apomorphine; the number of D-2 receptors (Bmax) in the striatum of the injected hemisphere increased compared with that of control rats. MPTP in young rats induced only short-lasting ipsiversive circling and no contraversive circling after apomorphine; the number of striatal D-2 receptors did not increase. These results suggest that the neurotoxicity of MPTP is age-dependent in the rat, and that MPTP has neurotoxic effects on the nigrostriatal dopaminergic system in old rats and induces dopamine receptor supersensitivity in the denervated striatum.  相似文献   
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This study was designed to examine the acute response of normal arterial wall to pulsed laser irradiation. Irradiation with an Excimer or a Holmium YAG laser was performed in 15 normal iliac sites of 8 male New Zealand white rabbits. The excimer laser was operated at 308 nm, 25 Hz, 50 mj/mm2/pulse, and 135 nsec/pulse and the Ho:YAG laser was operated at 2.1 μm, 3.5 Hz, 400 mj/ pulse, 250 μsec/pulse. The excimer and Ho:YAG laser were coupled into a multifiber wire-guided catheter of 1.4 and 1.5 mm diameter, respectively. The mean luminal diameter increased similarly from 2.01 ± 0.29 to 2.46 ± 0.27 mm (P < 0.0005) and from 2.09 ± 0.53 to 2.45 ± 0.30 mm (P < 0.005) after excimer and Ho:YAG laser irradiation, respectively. Perforation occurred in 3 of 15 Ho:YAG irradiated sites and 0 of 15 excimer laser irradiated sites. The sites irradiated with excimer or Ho:YAG laser had similar histologic features, consisting of shedding of the endothelium, disorganization of internal elastic lamina, localized necrosis of vascular smooth muscle cells, and fissures in the medial layer. However, the sites irradiated with excimer laser had lower grading scores than those irradiated with the Ho:YAG laser (P<0.05). Irradiation with excimer or Ho:YAG laser of normal arteries results in: (1) vasodilation of the irradiated artery; (2) localized mechanical vascular injury, and (3) Ho:YAG laser induces more severe damage to the arterial wall than excimer. © 1993 Wiley-Liss, Inc.  相似文献   
34.
Metastatic liver disease can modify the metabolic response to critical illness. Systemic lactic acidosis may arise from an increased production due to inadequate peripheral tissue oxygen transport, altered metabolic function such as depressed pyruvate oxidation or insufficient hepatic clearing capacity due to tumor replacement of functional liver mass. Hepatic venous catheterization in a patient with extensive metastatic melanoma to the liver and adult respiratory distress syndrome indicated a marked disparity between whole body and liver oxygenation which may arise due to a markedly stepped up splanchnic oxygen utilization unmatched by a proportionate rise in regional oxygen delivery. Since some neoplasms may exhibit increased metabolic activity, it is suspected that these metastatic lesions may have contributed to the observed regional hypermetabolism thereby worsening hepatic hypoxia and exacerbating lactic acidosis. This case also illustrates the difficulties in interpreting global indicators of metabolic function and oxygenation in critically ill patients.  相似文献   
35.
Zusammenfassung Mit Hilfe der Daten aus dem Nationalen Gesundheitssurvey wird die Frage diskutiert, inwieweit Angaben zu Krankheiten in einer Befragung zur Abschätzung von Prävalenzen für eine Gesundheitsberichterstattung herangezogen werden können. An dem Beispiel der Selbstangaben zum Herzinfarkt wird die Reliabilität und Plausibilität solcher Daten untersucht. Abschliessend werden diese Zahlen Daten aus anderen Quellen, wie dem Herzinfarkt-Register und Fragebogenerhebungen, gegenübergestellt, um beurteilen zu können, ob die Raten plausibel sind Da jedoch auch die anderen Datenquellen ihre Schwächen und Defizite haben, wird der Nutzen von krankheitsbezogenen Selbsteinschätzungen zum Herzinfarkt insgesamt als positiv bewertet, weil damit auch Beziehungen zu sozialen und verhaltensbezogenen Merkmalen untersucht werden können.
Summary With the data of the German National Health Survey the question is discussed, if self-reports on diseases, gained in a survey, are useful for estimating prevalences within the German population. Self-reports on myocardial infarction serve as an example for examining the reliability and plausibility of such data. The prevalence rate for myocardial infarction in this survey is compared with prevalence rates of other data sources as the MONICA-register and surveys. Because these other data sources have some problems and deficits according to their validity too, the value of self-reports on diseases from the National Health Survey is seen positively for establishing a health reporting system.

Résumé Les données de l'Enquête Nationale de la Santé en RFA sont discutées. La question est de savoir siles données subjectives de l'infarctus du myocarde peuvent être utilisées pour estimer des prévalences dans la population allemande. Dans cette étude les problèmes de compatibilité des données d'un questionnaire sont examinées et comparées avec des études similaires. Carles relevés du registre de l'infarctus du myocarde et d'autres enquêtes ont aussi des problèmes de validité, les données subjectives de l'Enquête Nationale sont jugées positivement pour estimer des prévalences de l'infarctus du myocarde. Avecces données il est posible en outre, d'analyser des prévalences se référant aux indicateurs sociaux et concernant une ligne de conduite pour la santé.
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The polymerase chain reaction (PCR) was used to detect varicella zoster virus (VZV) DNA in vesicle samples from patients with varicella and zoster. Primers and the oligonucleotide probe were chosen from the region of the immediate early gene 63. Procedures for preparing the DNA from the specimens were omitted, and the amplified DNA was directly detected in ethidium bromide-stained polyacrylamide or agarose gels, thus providing a rapid and less laborious assay. A total of 66 vesicle specimens including 3 crusts (collected on days 1-14 after the onset of exanthem) were tested by the simplified VZV-PCR, and 64 (97%) were positive. When the direct visualization of the amplified DNA was confirmed by DNA hybridization, a non-radioactive hybridization assay involving a digoxigenin-labelled oligonucleotide probe and detection by chemiluminescence proved as adequate as a radioactive hybridization assay. Thus, the VZV PCR described appears to be a useful diagnostic test for detecting and identifying varicella zoster virus.  相似文献   
38.
Extended -spectrum β -lactamases(ESBLs)aremainlyproducedbymembersofthefamilyEnter obacteriaceaewhichcanhydrolyzeβ -lactamantibi oticsincludingthethird - generationcephalosporinandaztreonam ,theESBLs- producingbacillishowedmedian -highresistancetoceftazidimeandaztreonamparticularly[1] .NowadaystheprevalenceofESBLs -producingstrainshavebeenreportedinmanyareasaroundtheworld[2 ] .ButthereisfewinformationabouttherelationshipbetweentheuseofantibioticandtheproductionofESBLs .Weperformedastud…  相似文献   
39.
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
40.
OBJECTIVE: This study was undertaken in order to determine the risk factors for pregnancies complicated by placental abruption in a socio-economically disadvantaged region in metropolitan Adelaide. METHODS: This was a retrospective case-control study including all singleton pregnancies resulting in placental abruption between 2001 and 2005. RESULTS: The overall incidence of placental abruption was 1.0%; the overall perinatal mortality among the births with abruption was 13%. Univariate analyses showed the following significant risk factors for placental abruption: preterm pre-labor rupture of the membranes (PRE-PROM; odds ratio (OR) 4.79, 95% confidence interval (CI) 1.52-15.08), non-compliance with antenatal care (OR 2.93, 95% CI 1.06-8.90), severe intrauterine growth restriction (IUGR), and elevated homocysteine levels (OR 45.55, 95% CI 7.05-458.93). Severe IUGR was significantly more common in the abruption group compared with the control group (p = 0.032). In the multivariate analysis, PRE-PROM remained a significant independent risk factor for placental abruption. Marijuana use, domestic violence, and mental health problems were more common (borderline significance) in the abruption group. Smoking and preeclampsia were not found to be associated with placental abruption in this study. CONCLUSIONS: In this high-risk population, PRE-PROM and elevated homocysteine levels appear to represent the major risk factors for placental abruption.  相似文献   
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