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101.
Objectives: To determine the severity of hepatic histological lesions in anti-HCV positive parenteral drug abusers and to correlate it with the level of ALT activity and HCV RNA determined by polymerase chain reaction (PCR).
Methods: Twenty-nine of the 62 anti-HCV-positive parenteral drug abusers who consecutively entered a Rehabilitation Center of Athens consented to liver biopsy and were prospectively and thoroughly followed up for a mean of 12.9 (range 6-33) months. Anti-HCV was detected by a second-generation enzyme immunoassay and confirmed by a second-generation recombinant immunoblot assay. Serum samples were tested for HCV RNA by nested PCR with primers from the highly conserved 5' untranslated region of the HCV genome.
Results: Liver biopsy revealed lesions compatible with chronic hepatitis in 26 (89.6%) and a normal liver in three (10.4%) of the 29 patients. In particular, 11 (37.9%) had minimal and 15 (57.1%) had mild chronic hepatitis; fibrosis was absent or mild in all cases. Histological grade and stage were significantly milder in patients with persistently normal ALT activity than in those with increased ALT activity. However, chronic hepatitis was observed in five (62.5%) of the eight patients with normal ALT levels. The presence of serum HCV RNA was not significantly correlated with the severity of histological lesions. HCV RNA was detected in 16 (57.1%) of the 28 cases tested. In particular, HCV RNA was detected in one (33.3%) of the three cases with normal liver and in three (37.5%) of the eight patients with normal ALT levels.
Conclusions: Liver biopsy appears to be the method of choice for the accurate evaluation of anti-HCV positive parenteral drug abusers, irrespective of ALT activity and presence of serum HCV RNA. Chronic hepatitis is observed in the majority and the state of "healthy" carrier of HCV in the minority of this epidemiological setting.  相似文献   
102.
We have identified a subset of CD56(+)CD3(-) human natural killer (NK) cells that express CD4 and the HIV coreceptors CCR5 and CXCR4. These cells can be productively infected in vitro by both CCR5- and CXCR4-using molecular clones of HIV-1 in a CD4-dependent manner. Analysis of HIV-infected persons showed that viral DNA is present in purified NK cells, and virus could be rescued from these cells after in vitro cultivation. Longitudinal analysis of the HIV-1 DNA levels in NK cells from patients after 1-2 years of highly active antiretroviral therapy indicated that NK cells remain persistently infected and account for a substantial amount of the viral DNA in peripheral blood mononuclear cells. These results demonstrate that a subset of non-T cells with NK markers are persistently infected and suggest that HIV infection of NK cells is important for virus persistence. The properties of the virus reservoir in these cells should be considered in attempts to further optimize antiretroviral therapies.  相似文献   
103.

Objective

Identify the psychosocial variables that predict smokers’ compliance with smoke-free policies at work, and non-smokers’ assertiveness for smoke-free rights in Greek and Bulgarian workplaces.

Methods

Data were collected from employees in Greece and Bulgaria. The main outcome measures were smokers’ compliance with smoke-free policies, and non-smokers’ assertiveness intentions. Demographic variables, tobacco use and dependence, as well as beliefs about second-hand smoke (SHS) exposure and smoking at work were also assessed.

Results

Regression analyses showed that smokers’ compliance with smoke-free policies was predicted by age, perceived health risks of smoking, and beliefs related to the benefits of smoking at work. Non-smokers’ assertiveness was predicted by annoyance from exposure to SHS at work, and assertiveness-related social cognitions (e.g., attitudes, social norms, and self-efficacy).

Conclusions

Interventions to promote support for tobacco control policies at work in Greece and Bulgaria may benefit from targeting smokers’ beliefs about the actual effects of tobacco use on health and job performance. Accordingly, efforts to promote non-smokers assertiveness should build stronger assertiveness-related attitudes, convey anti-smoking normative messages, and strengthen self-efficacy skills.  相似文献   
104.
105.
To further examine the genetic and clinical features of hypertrophic cardiomyopathy caused by mutations in the cardiac troponin T (cTnT) gene, we screened 143 probands from our hypertrophic cardiomyopathy population for mutations in this gene. We report that the Arg278Cys missense mutation in the cTnT gene had a different clinical presentation in 2 different families and was associated with a clinical profile that deviates from what is currently expected for cTnT gene mutations.  相似文献   
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Two daughters of a propositus with documented McArdle's disease were shown by enzyme assay, gel electrophoresis, and immunoblotting to be partially deficient in skeletal muscle phosphorylase and, presumably, heterozygous for the trait. Both exhibited only the adult form of the skeletal muscle isozyme. By 31P-nuclear magnetic resonance, both heterozygotes showed a greater production of acid during fully aerobic exercise than when blood flow was occluded in ischemic exercise. This pattern is in contrast to that of control subjects, where there is significantly greater acid production in ischemic versus aerobic exercise, and distinct from that of phosphorylase-negative patients in which no acid is produced in either circumstance. We suggest that these heterozygotes may have adapted to their diminished phosphorylase by enhancing utilization of plasma glucose. If so, this mechanism could account for the observation that most of the symptoms of McArdle's disease are often manifest only in adulthood. These studies also show that although there are very high concentrations of phosphorylase in skeletal muscle (approximately 2% of the soluble protein), such a high level is essential for normal muscle glycogenolysis.  相似文献   
109.
This article is the second of two parts outlining the objectives for resident rotations in intensive care units. It is part of a larger continuing series on the goals and objectives to direct the training of emergency medicine residents on off-service rotations. The critical care unit allows the resident an opportunity to provide continuing care for critically ill patients, many of whom enter the health care system through the emergency department. Critical care medicine is a natural continuum of emergency medicine, and provides the resident with the ability to follow the natural progression of seriously ill patients, as well as build confidence and experience in caring for the critically ill and injured. These objectives are designed to help focus the resident's reading and study during the rotation.  相似文献   
110.
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