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1.
The pharmacokinetics of the new fluoroquinolone antimicrobial ofloxacin were studied in 18 subjects with normal renal function or varying degrees of renal impairment, including patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis. Apparent total body and renal clearances declined and elimination half-life increased with decreasing creatinine clearance. CAPD and haemodialysis removed clinically insignificant fractions of ofloxacin body burden over the study period (6-15% and 9-11% of the dose, respectively). The apparent volume of distribution, peak concentration, time to peak concentration, and non-renal clearance were not altered significantly by renal insufficiency. An extended dosing interval of 24-48 h is recommended, depending upon the degree of renal impairment, when creatinine clearance falls below 50 mL/min. In addition, supplemental doses would not appear to be necessary during CAPD and following haemodialysis.  相似文献   
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Cutaneous manifestations of Lyme borreliosis   总被引:1,自引:0,他引:1  
Summary The dermatological symptoms of Lyme borreliosis present with a typical clinical pattern and characteristic time of appearance. In contrast to other manifestations of Lyme borreliosis they are easily recognizable in most of the cases. In the first stage, erythema migrans arises at the tick bite site. With this symptom the diagnosis of Lyme borreliosis can be established. During all manifestations of Lyme borreliosis the history of erythema migrans is an important parameter to verify the diagnosis. In the early stage of disease a lymphocytic proliferation can appear at the tick bite site, at the ear lobe, or at the mamilla. Borrelia lymphocytoma can be diagnosed when antibodies againstBorrelia burgdorferi are positive. Years after infection, acrodermatitis chronica atrophicans arises at distal body sites causing livid swelling and gradually skin atrophy. Skin lesions can be accompanied by neuropathies, mostly of the lower legs, which in contrast to the skin lesions, do not respond well to antibiotic therapy. There is evidence that some cases of Shulman syndrome, morphea and lichen sclerosus et atrophicus might be related to a borrelia infection as indicated by cultivation ofB. burgdorferi from skin biopsies of morphea and response to antibiotic treatment in some cases. The classical dermatological symptoms of Lyme borreliosis, erythema migrans, borrelia lymphocytoma and acrodermatitis chronica atrophicans respond to oral antibiotic treatment. In acrodermatitis chronica atrophicans parenteral antibiotic therapy is sometimes necessary.
Hautmanifestationen der Lyme-Borreliose
Zusammenfassung Dermatologische Manifestationen der Lyme-Borreliose zeichnen sich durch ihr charakteristisches Erscheinungsbild und durch den typischen Zeitpunkt ihres Auftretens aus und sind im Gegensatz zu anderen Symptomen meist gut zu diagnostizieren. Die Diagnose des Erythema chronicum migrans, das an der Zeckenstichstelle entsteht, erlaubt einerseits die exakte Diagnose einer Lyme-Borreliose und stellt in Spätstadien oft einen wichtigen anamnestischen Parameter zur Verifizierung einer durchgemachten Borrelieninfektion dar. Lymphozytäre Proliferationen können einerseits an der Zeckenstichstelle, andererseits auch an abstehenden Körperpartien beobachtet werden. Ein Borrelienlymphozytom kann dann diagnostiziert werden, wenn Antikörper gegenBorrelia burgdorferi nachweisbar sind. Die Acrodermatitis chronica atrophicans entsteht nach jahrelanger Latenz an abstehenden Körperpartien und führt zur Hautatrophie. Gelegentlich sind Begleitneuropathien möglich, welche im Gegensatz zu den Hautveränderungen auf die antibiotische Therapie nicht so gut ansprechen. Es gibt Berichte, wonach einige Fälle von Shulman Syndrom, Morphea und Lichen sclerosus et atrophicus auch durch eine Infektion mitB. burgdorferi verursacht werden. Die Isolierung vonB. burgdorferi aus Morphealäsionen dürfte dazu einen direkten Hinweis geben. Die klassischen dermatologischen Symptome Erythema chronicum migrans, Borrelienlymphozytom und Acrodermatitis chronica atrophicans sprechen auf orale antibiotische Therapie an. Bei letzterer Erkrankung muß manchmal auf eine parenterale antibiotische Therapie zurückgegriffen werden.
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OBJECTIVE: To test the hypothesis that short stature is associated with abdominal obesity, insulin resistance and lipid profile changes. METHODS: Anthropometric data were collected from 237 women (18-60 years old), residents of a shantytown in Maceió. Biochemical profiles of 60 individuals drawn from this population were determined. RESULTS: Total and low-density lipoprotein (LDL) cholesterol levels and insulin resistance rose with increasing waist : hip circumference ratio, particularly in women. Short, overweight individuals exhibited larger biochemical alterations than overweight individuals of average stature. CONCLUSION: Short stature, when associated with overweight, is a risk factor for increased insulin resistance and alterations in lipid profile.  相似文献   
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Specific receptors for bombesin/gastrin releasing peptide (GRP) on the androgen-independent human prostate cancer cell lines PC-3 and DU-145 were characterized. No specific binding of 125I-[Tyr4]-bombesin to the androgen-dependent human prostate cancer cell line LNCaP was detectable. The binding of 125I-[Tyr4]-bombesin to PC-3 and DU-145 cells was found to be time- and temperature-dependent, saturable, and reversible. Scatchard analysis revealed a single class of binding sites with high affinity (Kd 9.8 × 10?11 M for PC-3, and 9.1 × 10-11 M for DU-145 cells at 25°C) and with a binding capacity of 44,000 binding sites/cell and 19,000 binding sites/cell, respectively. Bound 125I-[Tyr4]-bombesin was rapidly internalized by PC-3 cells. The nonhydrolyzable GTP analog GTP-gamma-S caused a dose-dependent inhibition of 125I-[Tyr4]-bombesin binding to PC-3 and DU-145 cells, indicating that a G-protein (guanine nucleotide-binding protein) couples the bombesin receptor to intracellular effector systems. Bombesin and GRP(14-27) inhibited the binding of 125I-[Tyr4]-bombesin to both cell lines in a dose-dependent manner with inhibition constants (Ki of 0.5 nM and 0.4 nM, respectively. Both cell lines express the bombesin/GRP preferring bombesin receptor subtype, since, in displacement studies, neuromedin B was more than 200 times less potent than bombesin and GRP(14-27) in inhibiting the binding of 125I-[Tyr4]-bombesin. Two synthetic bombesin/GRP antagonists, RC-3095 and RC-3110, powerfully inhibited the specific binding of 125I-[Tyr4]-bombesin with Ki 0.92 nM and 0.26 nM on PC-3 cells, and 3.3 nM and 0.89 nM on DU-145 cells, respectively. These findings indicate that the PC-3 and DU-145 human prostate cancer cell lines possess specific high-affinity receptors for bombesin/GRP, and are suitable models for the evaluation of the antineoplastic activity of new bombesin/GRP antagonists in the treatment of androgen-independent prostate cancer. © 1994 Wiley-Liss, Inc.  相似文献   
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This study examined verbal-subjective, peripheral and central physiological responses of motor vehicle accident (MVA) survivors with subclinical posttraumatic stress disorder (PTSD), without PTSD symptoms as well as healthy controls. Seven persons of each group were exposed to positive, neutral, accident-related and negative, non-accident-related slides. The verbal-subjective ratings of the slides did not differ between the groups. In contrast to the verbal ratings of the trauma-related materials, the behavioral and physiological responses showed a remarkable dissociation from these reports. The startle responses were enhanced to accident-related slides only in the PTSD group and MVA survivors with PTSD had a significantly lower response to the neutral slides than MVA survivors without PTSD. P200 was lower to positive, neutral and negative slides in the PTSD group compared to both other groups. The late positive complex showed no group-related effects. The data suggest that traumatized persons with PTSD show exaggerated emotional responses to trauma-related stimuli and reduced cognitive responses to several types of stimuli that may interfere with the extinction of the emotional trauma memory.  相似文献   
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Eight genotypes (A-H) of hepatitis B virus (HBV) have been described, HBV genotypes F and H being autochthonous to America. HBV genotype F has been classified in four clusters. The objective of this study was to gain insight into the molecular epidemiology of HBV American genotypes, as well as to analyze the genotype-related polymorphism in some functional domains of the surface proteins. The sequences of the S region of 106 isolates genotype F and H were analyzed, out of which 47 isolates genotype F circulated in different Venezuelan populations. Most of the Venezuelan isolates genotype F were grouped in cluster III (n = 39) and 7 in cluster II. One isolate obtained from a blood donor could not be classified in any clade and harbored amino acid substitutions characteristic of a vaccine escape mutant (G145R) and a stop codon in the surface antigen. Amino acid analysis of the PreS and S gene products showed unique genetic characteristics in genotype F and H sequences in some important domains involved in the early steps of infection. Out of 30 available sequences, two complete genome sequences of HBV genotype F from Venezuela were obtained. Phylogenetic analysis of these complete genomes confirmed the presence of four clusters inside genotype F, differing in more than 4% nucleotide divergence. Our extended analysis showed that genotype F clades Ia, III, and IV exhibit a restricted geographic distribution (Central America, the North and the South of South America, respectively) while clades Ib and II are found in all the Americas except in the Northern South America and North America respectively.  相似文献   
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Major depression is conditionally linked to a polymorphism of the human serotonin transporter gene (SLC6A4). During the presentation of aversive, but not pleasant, pictures, healthy carriers of the SLC6A4 short (s) allele showed stronger activation of the amygdala on functional magnetic resonance imaging. s carriers also showed greater coupling between the amygdala and the ventromedial prefrontal cortex, which may contribute to the abnormally high activity in the amygdala and medial prefrontal cortex seen in major depression.  相似文献   
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The aim of this study was to test source modeling strategies for EEC-data from a clinical group of amputees. The experimental conditions (measuring time, age and condition of the patients) resulted in low quality EEC-data. Noise reduction was achieved by a principal component analysis (PCA) and a multiple signal classification (MUSIC). A comparison of the results of these two methods with traditional signal handling yielded superior results for the MUSIC algorithm.  相似文献   
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