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971.
PROBLEM/CONDITION: Much chronic disease and injury morbidity and mortality is associated with high-risk behaviors (e.g., cigarette smoking, excessive alcohol consumption, and physical inactivity) and with lack of preventive health care (e.g., screening for cancer). States use the Behavioral Risk Factor Surveillance System (BRFSS) to collect data about these modifiable health behaviors and to monitor trends and significant changes in their populations over time. REPORTING PERIOD: 1992 and 1993. DESCRIPTION OF SYSTEM: The BRFSS is a state-based telephone survey of the civilian, noninstitutionalized, adult (persons > or = 18 years of age) population. In 1992, 48 states and the District of Columbia participated in the BRFSS; in 1993, 49 states and the District of Columbia participated. Several questions were added to the BRFSS in 1993. RESULTS: As in previous years, state-specific variations occurred in the prevalence of high-risk behaviors, awareness of certain medical conditions, use of preventive health services, and health-care coverage. In 1993, 4.0% (range: 1.4% - 6.4%) of adults reported riding with a driver who had had too much alcohol to drink. The percentage of persons > or = 50 years of age who had ever had a proctoscopic examination ranged from 25.6% to 51.5% (median: 36.8%). Among adults > or = 65 years of age, 27.4% (range: 18.5 % - 40.0%) had ever had a pneumococcal vaccination, and 49.9% (range: 28.7% - 66.2%) had had an influenza vaccination within the past 1 year. INTERPRETATION: The variations in prevalence across states likely reflect socioeconomic differences, differences in state laws enacted to discourage risky behaviors, different levels of effort to screen for certain types of cancer or risk factors for other diseases, and other factors. ACTION TAKEN: States will continue to use the BRFSS to collect data about health behaviors. Analysis of these data will enable states to monitor factors that may affect the rate of chronic disease and injury mortality and morbidity and to develop public health policies to address these problems. 相似文献
972.
973.
DI Axel BR Brehm K Wolburg-Buchholz EL Betz G K?veker KR Karsch 《Canadian Metallurgical Quarterly》1996,33(4):327-339
Cell-to-cell interactions are mainly involved in the control of the proliferation, migration, differentiation and function of different cell types in a wide range of tissues. In the arterial vessel wall, human arterial endothelial cells (haEC) and smooth muscle cells (haSMC) coexist in close contact with each other. In atherogenesis, haSMC can migrate from the media to the subintimal space to form fibromuscular and atheromatous plaques. In the present study, a transfilter coculture system is described, in which the interface between haSMC and confluent or proliferative haEC can be studied in detail. Cells were cocultured on the opposite sides of a porous filter which separates both cell types like the internal elastic lamina in vivo. In cocultures containing proliferative haEC, haSMC growth was significantly stimulated (33.4 +/- 5.7 cells/section, p < 0.05) compared to haSMC monocultures (22.9 +/- 2.5 cells/section) and cocultures containing confluent haEC (15.6 +/- 2.9 cells/section). If confluent haEC were injured mechanically, haSMC growth increased highly significantly (71.3 +/- 16.8 cells/section, p < 0.001). Thus, cell-rich proliferates containing 5-7 layers of haSMC embedded in extracellular matrix were formed after 14 days. On the other hand, after haSMC migration to the endothelial side had occurred, the addition of LDL and monocytes to cocultures with arterial media explants and haEC resulted in the formation of lipid-rich, low-cellular structures. After 28 days, characteristic in vitro plaque growth was induced; the plaque contained a lipid core with predominantly necrotic cells, extracellular lipid accumulations, atypically shaped lipid-loaded haSMC and macrophages, similar to in vivo foam cells, as well as an increased amount of extracellular matrix (collagen I, III and IV). These areas were surrounded by typical fibromuscular caps consisting of smooth muscle alpha-actin-positive haSMC. Finally, the formation of capillaries by haEC could also be observed within these structures. 相似文献
974.
975.
CM Waterman-Storer SB Karki SA Kuznetsov JS Tabb DG Weiss GM Langford EL Holzbaur 《Canadian Metallurgical Quarterly》1997,94(22):12180-12185
Fast axonal transport is characterized by the bidirectional, microtubule-based movement of membranous organelles. Cytoplasmic dynein is necessary but not sufficient for retrograde transport directed from the synapse to the cell body. Dynactin is a heteromultimeric protein complex, enriched in neurons, that binds to both microtubules and cytoplasmic dynein. To determine whether dynactin is required for retrograde axonal transport, we examined the effects of anti-dynactin antibodies on organelle transport in extruded axoplasm. Treatment of axoplasm with antibodies to the p150(Glued) subunit of dynactin resulted in a significant decrease in the velocity of microtubule-based organelle transport, with many organelles bound along microtubules. We examined the molecular mechanism of the observed inhibition of motility, and we demonstrated that antibodies to p150(Glued) disrupted the binding of cytoplasmic dynein to dynactin and also inhibited the association of cytoplasmic dynein with organelles. In contrast, the anti-p150(Glued) antibodies had no effect on the binding of dynactin to microtubules nor on cytoplasmic dynein-driven microtubule gliding. These results indicate that the interaction between cytoplasmic dynein and the dynactin complex is required for the axonal transport of membrane-bound vesicles and support the hypothesis that dynactin may function as a link between the organelle, the microtubule, and cytoplasmic dynein during vesicle transport. 相似文献
976.
A high-performance liquid chromatography assay for hydroxyurea in human serum was developed based on a commercial colorimetric assay kit for urea (Sigma Diagnostics). Serum (0.5 ml), spiked with methylurea as an internal standard, was treated with 70% perchloric acid. Supernatant (0.2 ml) was combined with 0.7 ml of BUN acid reagent and 0.6 ml of BUN color reagent. The resulting colored reactant (100 microl) was analyzed on a 300 x 3.9 mm Bondclone 10 C18 column coupled with a UV-Vis detector, at 449 nm. The mobile phase was 13% acetonitrile in water. Retention times of colored derivatives of hydroxyurea and methylurea were 6.5 and 12.2 min, respectively. The log-log calibration curve was linear from 0.0065 to 1.31 mM. Average accuracy was 99.9+/-4.0% and the intra- and inter-day error of assay did not exceed 11%. 相似文献
977.
H van Keulen DE Feely PT Macechko EL Jarroll SL Erlandsen 《Canadian Metallurgical Quarterly》1998,84(2):294-300
OBJECTIVES: To present our experience with the results of three different methods of treatment of idiopathic varicoceles. METHODS: A total of 301 patients with 417 varicoceles were retrospectively assigned into three groups according to the method of treatment. Group 1 included 94 patients with 131 varicoceles treated by open surgery. Group 2 consisted of 120 patients with 163 varicoceles treated by percutaneous retrograde sclerotherapy, and in group 3, 87 patients with 123 varicoceles were treated by laparoscopic varicocelectomy. Of all patients, 222 (73.8%) were closely followed up with clinical and Doppler ultrasound examinations 6 and 12 months after the treatment. Seminal analysis was carried out before treatment and repeated in 172 patients with subfertility or infertility 4 to 6 months after treatment. RESULTS: Patients in the three treatment groups were balanced regarding the different variables. The mean operative time was significantly shorter among patients with open surgery. The cost of sclerotherapy is one fourth to one fifth that of surgery and the cost of laparoscopy is double. Sclerotherapy was successful in 96 (82.8%) of 116 left varicoceles and in only 24 (51%) of 47 right varicoceles. The recurrence rate at follow-up was not significantly different among the three groups. The recurrence rate increased progressively with the increase of varicocele size from grade I to grade III in all groups. The overall incidence of postoperative complications was significantly higher among patients with open surgery. Postoperative spermiogram showed a significant increase in the density and motility and a significant reduction in the percentage of abnormal forms in all groups. The pregnancy rate was approximately similar in all groups. CONCLUSIONS: First, sclerotherapy is best used for isolated left-sided varicoceles. Second, laparoscopy is the treatment of choice for bilateral varicoceles. Finally, open surgery still has a role in isolated right-sided varicoceles and in left-sided cases with failed sclerotherapy. 相似文献
978.
N Lewin-Epstein T Sagiv-Schifter EL Shabtai A Shmueli 《Canadian Metallurgical Quarterly》1998,36(9):1361-1370
OBJECTIVES: In the past few years, the SF-36 Health Survey has drawn considerable attention from researchers in non-English-speaking countries. This report contributes to the growing body of literature on this instrument by reporting the results of a national study conducted in Israel. The study examined the psychometric properties of the Hebrew translation based on a sample of the adult population of Israel and evaluated the results from a cross-national perspective. METHODS: The sample included 2,030 adults drawn from the Jewish population, aged 45 to 75 years. The SF-36 Health Survey was administered in face-to-face interviews as part of a broader health study. RESULTS: The pattern of correlations among items and the internal consistency scores pointed to high reliability. Confirmatory factor analysis using the Amos 3.61 program supported the hypothesized factorial structure. Specifically, the items clustered around eight health dimensions, as was found in studies in other societies. Clear and statistically significant differences in the SF-36 Health Survey scores were found among age groups and population groups distinguished by the degree of chronic health problems. CONCLUSIONS: Results of the analysis indicate that the instrument provided an appropriate measure of general health status. The findings clearly indicate that the translation into the Hebrew language and the application of the instrument to a culturally heterogeneous population did not diminish the qualities of the instrument. They also point to certain items that might be modified to reduce problems of synonimity and embeddedness. 相似文献
979.
EL Le Prisé 《Canadian Metallurgical Quarterly》1998,2(6):763-770
Prognosis of oesophageal cancer is poor. There have been phase II-III trials of postoperative chemotherapy with the aim of improving survival. Chemoradiotherapy seems more promising than both chemotherapy and radiotherapy alone. In contrast, better results obtained with chemoradiotherapy were associated with an increase in morbidity and mortality, and finally overall survival was uncommonly improved. It is necessary to implement new multidisciplinary randomised trial. 相似文献
980.
L Vázquez G Maldonado C Agundis A Pérez EL Cooper E Zenteno 《Canadian Metallurgical Quarterly》1997,279(3):265-272
Recombinant vaccinia virus (VV) vectors that express the envelope (Env) protein of the human immunodeficiency virus-type 1 (HIV-1) have been previously shown to elicit HIV-specific cytotoxic T-lymphocyte (CTL) and weak antibody responses in non-human primate studies and clinical trials. In first clinical trials, single Env proteins were presented to the immune system by VV recombinants and other vectors, but individuals were not protected against later exposures to heterologous HIV. It is likely that the generation of protective immune responses against diverse HIV will require that vaccines encompass proteins from not just one, but multiple distinct HIV isolates. Here is described the simple construction of numerous new VV, each expressing a unique, truncated, Env protein (VVenv). Mouse experiments were performed to evaluate the ability of these VVenv to elicit immune responses. HIV-1-specific antibodies appeared within one month following one intraperitoneal inoculation of mice with single or mixed VVenv, reaching plateau levels by 4 months. The magnitude of antibody production was poor at the dose of 10(5) p.f.u. VVenv per animal, but improved with increasing doses of VVenv up to 10(7) p.f.u. per animal. The subcutaneous route of VV immunization, previously proven safe in human trials, was also effective for administering VVenv. These results highlight the strengths of recombinant VV constructs as vehicles for the presentation of multiple HIV-1-Env proteins to the naive immune system. 相似文献