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991.
Bang KM Althouse RB Kim JH Game SR 《International journal of occupational and environmental health》1999,5(4):251-255
The authors examined the temporal trends of age-specific pneumoconiosis mortality from coal worker's pneumoconiosis (CWP), asbestosis, and silicosis in the United States in 1985-1996. Mortality data were derived from the National Center for Health Statistics multiple causes of death files for the period. Age-specific mortality rates were computed for three age groups (15-44, 45-64, and > or = 65 years) among decedents with mention of CWP, asbestosis, or silicosis. Linear regression analysis was performed to examine the annual changes in age-specific mortality rates, by age group, with each specific condition. The CWP mortality rates declined significantly (p = 0.0001) in the groups 45 years old and older, but not in the age group 15-44. Asbestosis mortality rates declined significantly (p = 0.005) for the age group 45-64, while increasing (p = 0.0001) for those aged 65 years and older. However, in the younger age group 15-44, the rates showed no significant trend. Silicosis mortality rates declined significantly (p = 0.0001) for all groups. The continued occurrence of deaths from CWP, asbestosis, and silicosis among young adults may be the result of high levels of exposure to occupational risks. These results suggest that pneumoconiosis surveillance may help to evaluate the temporal pneumoconiosis mortality patterns in the United States. 相似文献
992.
Jie Jin Wang Paul Mitchell Wayne Smith Stephen R. Leeder 《Australian and New Zealand journal of public health》1999,23(2):147-153
OBJECTIVE: To assess prevalence and risk factors associated with use of community support services in a representative older Australian population. METHODS: The Blue Mountains Eye Study surveyed 3,654 people aged > or = 49 years, 82.4% of eligible residents from an area west of Sydney during 1992-94. Questions about use of community support services were asked during face-to-face interview. Information on marital and living status, socio-economic status measures, past medical history and self-ranked health status were also collected. RESULTS: 186 (5.4%) persons including 124 women (6.3%) and 62 men (4.2%) reported regular use of community support services, including Meals-on-Wheels (n = 52), Home Care (n = 147) or visits from a community nurse (n = 63). All three services were used by 17 persons and two services by 42 persons. There was a marked age-related increase in use of services from 1.8% in persons aged < 60 years to 25.3% in persons aged 80+ years. Factors significantly associated with use of community services in a multivariate model were: age (OR 1.7 per age decade), living alone (OR 2.5), walking disability (OR 4.1), visual impairment (OR 3.0), stroke history (OR 2.2), arthritis history (OR 1.8), low perceived health status (OR 1.7), cancer history (OR 1.7) and a history of any falls in the past 12 months (OR 1.6). CONCLUSIONS: Our study has found a wide range of health-related factors that impact on the use of community support services, particularly conditions causing difficulty in walking. IMPLICATIONS: These data may assist health planners in identifying target populations for the provision of community support services. 相似文献
993.
采用高效液相凝胶色谱法(GC-HPLC)、醋酸纤维膜电泳和半微量定氮法测定50%声振人血白蛋白空气微球制剂中球壁蛋白的含量。GC-HPLC确证了球壁蛋白主要成分为人血白蛋白;醋酸纤维膜电泳测定空气人血白蛋白微球制剂中人血白蛋白纯度>90%;半微量定氮法测出球壁蛋白含量平均值为3.56%左右,99%正常值范围为2.52%-4.60%。 相似文献
994.
Heel pain in children is common, and its evaluation is challenging. Medical history and physical examination may be unrevealing owing to children's limited communication skills. Often, advanced laboratory and imaging studies are required to make an accurate diagnosis. The most common causes of heel pain in children are apophysitis, enthesopathy, and overuse syndromes such as tendinitis. Juvenile rheumatoid arthritis is relatively uncommon. In very active children, occult fractures must also be evaluated. Pain unrelated to activity may indicate tumors, infection, or congenital problems. In general, heel pain in children is treated nonoperatively. For fractures in particular, children are less likely than adults to receive surgical treatment. 相似文献
995.
Epidemiology of rotavirus diarrhea in Egyptian children and implications for disease control. 总被引:3,自引:0,他引:3
A B Naficy R Abu-Elyazeed J L Holmes M R Rao S J Savarino Y Kim T F Wierzba L Peruski Y J Lee J R Gentsch R I Glass J D Clemens 《American journal of epidemiology》1999,150(7):770-777
Reliable epidemiologic data are essential for formulating effective policy to control rotavirus disease through immunization. The objective of this study was to describe the epidemiology of rotavirus diarrhea in a population-based cohort of children under 3 years of age residing in Abu Homos, Egypt, in 1995-1996. Rotavirus diarrhea incidence rates (episodes per person-year) were 0.13 for infants aged <6 months, 0.61 for those aged 6-11 months, 0.17 for those aged 12-23 months, and 0.15 for those aged 24-35 months. Fifty-six percent of children with rotavirus diarrhea had clinical dehydration; 90% of rotavirus diarrheal episodes occurred between July and November. In infants under 1 year of age, receipt of breast milk was associated with a lower incidence of rotavirus diarrhea. No other sociodemographic or environmental factor was found to be significantly associated with rotavirus diarrhea. Of 46 rotavirus isolates with strains identified, 41 (89%) were G serotypes 1 and 2. Rotavirus diarrhea was a major cause of morbidity in this cohort. Promotion of breastfeeding may exert a protective effect in young infants in this setting, but improvements in water and sanitation are unlikely to be effective preventive measures. The use of effective immunization against rotavirus in early infancy should be considered a public health priority. 相似文献
996.
N. T. Kim Oanh B.-E. Bengtsson L. Bætz Reutergårdh D. T. Hoa P.-A. Bergqvist D. Broman Y. Zebühr 《Archives of environmental contamination and toxicology》1999,37(3):303-309
A bleached sulfate integrated pulp and paper mill producing printing and writing paper from mixed tropical hardwood and
bamboo was studied. The mill uses a “conventional bleaching sequence,” C-E-H1-H2, with an average molecular chlorine consumption
of 50 kg per ton of air-dried pulp (ADP). The content of polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs)
in the bleaching filtrate in terms of the nordic toxicity equivalent (N-TEQ) was 33.5, 1.15, 0.56, and 0.014 pg/L for the
E, C, H1, and H2 bleaching stages, respectively. The corresponding PCDFs and PCDDs loads in ng/t ADP were in the same ranking,
i.e., 670, 69, 11.2, and 0.28, respectively. The congener and isomeric pattern of PCDFs and PCDDs of the bleaching filtrate and
the bleached pulp was found to be typical for the chlorine bleaching plant effluent. The obtained dioxin load formed in the
mill is in agreement with Western studies for the given multiple chlorine of 0.21–0.23. The load is, however, lower than reported
discharges from Scandinavian mills using 1980s bleaching technologies, but substantially higher than the discharges from mills
with modern bleaching technologies. Modifications in the bleaching plant to reduce molecular chlorine use are necessary to
reduce dioxin formation.
Received: 15 July 1998/Accepted: 17 March 1999 相似文献
997.
Expression of calcium channel alpha1 subunits in oocytes or cell lines has proven to be a powerful method in the analysis of structure-function relations, but these experimental systems are of limited value in the examination of neuron-specific functions such as transmitter release. Cell lines derived from neurons are often capable of these functions, but their intrinsic calcium channel alpha1 subunits are complicating factors in experimental design. We have examined the biophysical and molecular properties of calcium channels in a little studied neuroblastoma-glioma hybrid cell line, 140-3, a close relative of the NG108-15 cell line, to test whether this cell line might serve a role as an expression system for neural mechanisms. This cell was selected as it contains an intact transmitter release mechanism yet secretes little in response to depolarization. Patch-clamp recording revealed only a prominent low-threshold, rapidly inactivating calcium current with a single-channel conductance of approximately 7 pS that was identified as T type. A search for calcium channel alpha1 subunit messenger RNA in the 140-3 cells with three different tests only revealed alpha1C, whereas alpha1A-alpha1C were present in the parent NG108-15 line. We made a particular effort to search for alpha1E, since this subunit has been associated with a low-voltage-activated current. Our findings suggest that, since the principal nerve terminal-associated calcium channels (alpha1A, alpha1B, alpha1E) are absent in the 140-3 cell, this cell line may prove a particularly useful model for the analysis of the role of high-voltage-activated calcium channels in complex functions of neuronal cells. 相似文献
998.
Endoscopic surgery for obstructive hydrocephalus 总被引:12,自引:0,他引:12
Endoscopic surgery is popular in the neurosurgical field. The purpose of this study was to determine the role of endoscopy in obstructive hydrocephalus. From 1989 to 1999, we performed 81 endoscopic third ventriculostomies and 10 septostomies. Seventy-one of 81 operations were performed with endoscopic third ventriculostomy alone and 10 patients had endoscopic third ventriculostomy and ventriculoperitoneal shunt simultaneously. Age distribution varied from 2 months to 62 years of age. Our selection criteria included aqueductal stenosis (39 patients) and obstructive hydrocephalus due to tumor or cyst (42 patients). The most common candidate for endoscopic septostomy was atresia of the foramen of Monro (4 patients). Endoscopic septostomy was also performed to simplify shunting in patient; with multiseptated ventricle due to shunt infection, germinoma, thalamic tumor, craniopharyngioma, cyst and brain abscess. Sixty-five of 71 patients who were treated with endoscopic third ventriculostomy alone showed successful results (91.5%). However, 6 patients had unsatisfactory results and they needed a ventriculoperitoneal shunt. With no mortality, transient surgical complications were observed in 7 patients: 2 transient diabetes insipidus from electrical injury to the pituitary stalk, 1 epidural hematoma from sudden drainage of CSF, 1 delayed intraventricular hemorrhage. 2 obstruction of fenestration site and 1 transient memory disturbance from injury to the fornix. Endoscopic septostomy was useful in simplifying shunting in all cases with complicated hydrocephalus. Endoscopic surgery is straightforward and effective in appropriately selected cases with obstructive by drocephalus. 相似文献
999.
1000.
Somnay-Wadgaonkar K Nusrat A Kim HS Canchis WP Balk SP Colgan SP Blumberg RS 《International immunology》1999,11(3):383-392
In order to better understand the role of intestinal CD1d, we sought to define the cellular localization and further characterize the biochemical structure of CD1d in human intestinal epithelial cells (IEC). Using a CD1d-specific rabbit anti-gst-CD1d antibody, immunoprecipitation of radiolabeled cell surface proteins detected a previously identified 37 kDa protein as well as a 48-50 kDa protein which were confirmed by Western blotting with a CD1d-specific mAb, D5. Immunoprecipitation of protein lysates with the CD1d-specific mAb, D5 and 51.1.3, and the beta2-microglobulin (beta2m)-specific mAb, BBM.1, followed by N-glycanase digestion and Western blotting with the D5 mAb showed that the 48-50 kDa protein was a beta2m-associated, CD1d glycoprotein. CD1d was immunolocalized to the apical and lateral regions of native small and large intestinal IEC as defined by confocal laser microscopy using the D5 mAb and the rabbit anti-gst-CD1d antibody. In addition, a large apical intracellular pool of CD1d was identified. Identical observations were made with polarized T84 cells. Selective biotin labeling of apical and basolateral cell surfaces followed by immunoprecipitation with the D5 mAb, N-glycanase digestion and avidin blotting confirmed the presence of glycosylated CD1d on both cell surfaces and immunolocalization of the 37 kDa non-glycosylated form of CD1d to the apical cell surface. These studies show that CD1d is located in an ideal position for luminal antigen sampling and presentation to subjacent intraepithelial lymphocytes. 相似文献