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61.
Serum concentrations of soluble human leukocyte class I antigens (sHLA-I) and of the intercellular adhesion molecule-1 (sICAM-1) are increased in the early inflammatory stages of several immune-related diseases. These soluble molecules also exert immunomodulatory activity, including regulation of natural killer (NK) cell cytotoxicity. The aim of this study was to verify whether sHLA-I and sICAM-1 serum concentrations are related to the various stages of pelvic endometriosis, which is an immune-related disorder associated with impaired in-vitro NK cell activity. Serum sHLA-I and sICAM-1 concentrations were similar in patients and in healthy donors. However, when evaluated according to disease stage, sHLA-I and sICAM-1 concentrations were higher in patients with endometriosis stage I-II (revised American Fertility Society classification), or with non-pigmented peritoneal lesions. In conclusion, studies on sHLA-I and sICAM-1 may help to clarify the pathogenic mechanisms of endometriosis, and their serum concentrations may serve as additional markers for the early detection of recurrence of the disease during the monitoring of treatment outcome.  相似文献   
62.
We describe a patient with a non-0:1, non-0:139 Vibrio cholerae septicemia associated with ecythema gangrenosa-like skin lesions. The patient acquired the infection in Puerto Rico. Given the high fatality rate, it is important for the medical community to consider the diagnosis in high risk patients with exposures in Puerto Rico tropical waters.  相似文献   
63.
Blood pressure (BP) is recursively variable during the day-night cycle because of a physiological circadian rhythm. The aim of this study is, therefore, to show how to construct the population reference limits (desms) for BP in its time varying 24-h pattern, starting from a small sample, in order to facilitate their use in a local context. The sample for standardization comprised 427 clinically healthy subjects (211 males and 216 females), ranging in age from 16 to 100 years, attending their routine activities. The procedure begins with the statistical biometry related to the sample, and proceeds with the computation of the BP desms related to (1) the time-qualified discrete values; (2) the parameters of circadian rhythm; (3) the daily pressure load. The pertaining rules are explained step by stop, allowing each one to prepare the proper local desms for BP 24-h pattern. These standards may be useful for validating the individual BP monitoring according to the upper limits of the circadian physiological variability in the diagnostic procedure for identifying hypertensive subjects.  相似文献   
64.
The amino acid sequences of two ribonucleases from a callus cell culture of Panax ginseng were determined. The two sequences differ at 26% of the amino acid positions. Homology was found with a large family of intracellular pathogenesis-related proteins, food allergens and tree pollen allergens from both dicotyledonous and monocotyledonous plant species. There is about 30% sequence difference with proteins from species belonging to the same plant order (Apiales: parsley and celery), 60% with those from four other dicotyledonous plant orders and about 70% from that of the monocotyledonous asparagus. More thorough evolutionary analyses of sequences lead to the conclusion that the general biological function of members of this protein family may be closely related to the ability to cleave intracellular RNA and that they have an important role in cell metabolism. As the three-dimensional structure of one of the members of this protein family has been determined recently [Gajhede et al., Nature Struct Biol 3 (1996) 1040-1045], it may be possible to assign active-site residues in the enzyme molecule and make hypotheses about its mode of action. Structural features in addition to the cellular site of biosynthesis indicate that this family of ribonucleases is very different from previously investigated ones.  相似文献   
65.
The autonomic tone has been shown to influence the duration of the QT interval, however the independent contribution of sympathetic and parasympathetic tone is not fully elucidated. The influence of autonomic tone on QT duration was studied in 10 young healthy volunteers by evaluating the changes in QT and RR duration induced by i.v. isoproterenol infusion and by standing before and after i.v. administration of propranolol or atropine. Furthermore, the relationship between RR interval and QT duration was evaluated during nocturnal sinus arrhythmia and submaximal exercise test. Low doses of isoproterenol reduced RR (p < 0.01) but not QT interval duration, while higher doses influenced both RR (p < 0.0001) and QT (p < 0.001) duration. Propranolol did not influence standing-induced shortening of RR and QT intervals; on the contrary, atropine administration abolished standing-induced QT interval shortening, without influencing RR changes. QT duration resulted significantly related to preceding RR interval at peak exercise (r = 0.87, p < 0.001) and during nocturnal sinus arrhythmia (r = 0.73, p < 0.0005), however, the regression lines showing the correlation between QT and preceding RR interval were different. Both sympathetic and parasympathetic tone appear to contribute to heart rate-independent changes in QT duration. In the basal state parasympathetic more than sympathetic tone influences the relation QT-heart rate. Major increases of sympathetic nervous system activity may change the relation QT-heart rate. Thus, in case of abrupt autonomic changes, any proposed formula for heart rate correction of QT may result inappropriate, also in the normal range of heart rate.  相似文献   
66.
Angina, myocardial infarction, and sudden cardiac death are associated with thrombus formation in coronary arteries. It is generally believed that these conditions benefit from long-term exercise. However, the evidence for such amelioration or prevention is inconclusive and so is the mechanism through which long-term exercise exerts its beneficial effect on various ischaemic conditions. Because of the thrombotic events, the effects of exercise on platelet reactivity, blood coagulation and fibrinolysis have been extensively studied, but the findings are not consistent (1-9). This is mainly due to methodological problems. Analysis of platelet response to a variety of agonists and the dozen of coagulation and fibrinolysis variables makes the assessment of the overall platelet function, coagulation and fibrinolysis status extremely difficult.  相似文献   
67.
Cigarette smoke is a significant source of cadmium, lead, and toxic elements, which are absorbed into the human organism. In this context, the aim of this study was to investigate in vitro the presence of toxic elements, cadmium, and lead deriving from cigarette smoke in the resin composite, dentine, and dental enamel. Eight cylindrical specimens were fabricated from resin composite, bovine enamel, and root dentin fragments that were wet ground and polished with abrasive paper to obtain sections with 6‐mm diameter and 2‐mm thickness. All specimens were exposed to the smoke of 10 cigarettes/day during 8 days. After the simulation of the cigarette smoke, the specimens were examined with scanning electron microscopy (SEM) and the energy‐dispersive X‐ray analysis. In the photomicrographic analysis in SEM, no morphological alterations were found; however, the microanalysis identified the presence of cadmium, arsenic, and lead in the different specimens. These findings suggest that the deposition of these elements derived from cigarette smoke could be favored by dental structures and resin composite. Microsc. Res. Tech., 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
68.
Quantitative methodologies for the global in-depth comparison of proteomes are frequently based on chemical derivatization of peptides with isotopically distinguishable labeling agents. In the present work, we set out to study the feasibility of the dimethyl labeling method in combination with ZIC-cHILIC (zwitterionic hydrophilic interaction liquid chromatography) technology for quantitative proteomics. We first addressed the potential issue of isotope effects perturbing the essential coelution of differently labeled peptides under ZIC-cHILIC separation. The deuterium incorporation-induced effect can be largely eliminated by favoring the mixed-mode ZIC-cHILIC separation based on combined hydrophilic and ionic interactions. Then, we evaluated the performance and applicability of this strategy using a sample consisting of human cell lysate. We demonstrate that our approach is suitable to perform unbiased quantitative proteome analysis, still quantifying more than 2500 proteins when analyzing only a few micrograms of sample.  相似文献   
69.
Traditionally air quality networks have been carrying out the continuous, on-line measurement of volatile organic compounds (VOC) in ambient air with GC-FID. In this paper some identification and coelution problems observed while using this technique in long-term measurement campaigns are described. In order to solve these problems a GC-MS was set up and operated simultaneously with a GC-FID for C2-C11 VOCs measurement.There are few on-line, unattended, long term measurements of atmospheric VOCs performed with GC-MS. In this work such a system has been optimized for that purpose, achieving good repeatability, linearity, and detection limits of the order of the GC-FID ones, even smaller in some cases. VOC quantification has been made by using response factors, which is not frequent in on-line GC-MS. That way, the identification and coelution problems detected in the GC-FID, which may led to reporting erroneous data, could be corrected.The combination of GC-FID and GC-MS as complementary techniques for the measurement of speciated VOCs in ambient air at sub-ppbv levels is proposed. Some results of the measurements are presented, including concentration values for some compounds not found until now on public ambient air VOC databases, which were identified and quantified combining both techniques. Results may also help to correct previously published VOC data with wrongly identified compounds by reprocessing raw chromatographic data.  相似文献   
70.
Some organochlorine compounds, such as polychlorinated biphenyls (PCBs), have a tendency to bioaccumulate in humans and predators at the top of the food chain. We have recently confirmed the transplacental transfer of these compounds and the present study has been designed on the same material with the aim of investigating their potential health effects on newborns from 70 pregnant women, resident in a Northern Italy industrial town. Organochlorine compounds [namely, p,p′-dichlorodiphenyltrichloroethane (p,p′-DDT), p,p′-dichlorodiphenyldichloroethene (p,p′-DDE), hexachlorobenzene (HCB), and PCBs] have been analyzed both in cord and maternal serum, placenta, and maternal subcutaneous adipose tissue by GC-MSD. p,p′-DDT levels in the adipose tissue resulted significantly (p < 0.05) related to birth length. Mothers of neonates born by preterm programmed caesarean delivery showed significantly (p < 0.005 for both) higher serum p,p′-DDE serum concentrations and p,p′-DDT levels in the adipose tissue, as compared to mothers delivering at term.  相似文献   
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