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81.
Although tractors account for the majority of fatal farming-related injuries, little is known about the magnitude of this problem. The study population in this article was obtained from the five state Regional Rural Injury Study-I (RRIS-I) database that included 3939 farm households and 13,144 persons interviewed during 1990. Rates were calculated for sociodemographic variables and various exposures; logistic regression was used to calculate the relative risks and respective confidence intervals. Among the total farming-related injury events (n = 764), 65 (8.4%) were related to regular tractor (> or = 20 horsepower) use (495 injured persons per 100,000 persons per year). The rates increased incrementally for those persons working between 20 to 39 and 60 to 79 hours per week (range, 529 to 1430 per 100,000 persons). Among the 12 rollover events, there were only three injuries. The majority of injury events occurred while persons were mounting or dismounting the tractor (42%). Although only 7% of the cases were hospitalized, 83% required some type of health care. Among all injured persons, 43% were restricted from regular activities for 1 week or more and 20% were restricted for 1 month or more; 28% continued to have persistent problems. The finding of the large proportion of events associated with activities of mounting and dismounting suggests a need to investigate specific design characteristics of the tractors associated with these events and, in general, the tractors to which the population is exposed.  相似文献   
82.
Hepatic lipase (HL) hydrolysis of phosphatidylcholine (PC) was studied in recombinant high-density lipoprotein particles (r-HDL). r-HDL were made from cholate mixed micelles that contained PC, apo AI, and, in some cases, unesterified cholesterol. r-HDL were characterized using chemical composition, nondenaturing gradient gel electrophoresis, transmission electron microscopy, and dynamic light scattering. The r-HDL were found to be discoidal and in the size range of native HDL. Upon treatment of cholesterol-containing r-HDL with lecithin-cholesterol acyltransferase (LCAT), to form cholesteryl ester, the discoidal r-HDL became spheroidal. The effects of r-HDL morphology and size on HL activity were studied on r-HDL made of palmitoyloleoyl-PC, unesterified cholesterol, cholesteryl ester, and apolipoprotein AI. Spheroidal r-HDL were hydrolyzed at a faster rate than discoidal r-HDL. Protein-poor r-HDL were hydrolyzed by HL at a faster rate than protein rich r-HDL. Unesterified cholesterol had no apparent effect on particle PC hydrolysis. The hydrolysis of different species of PC [dipalmitoyl (DPPC), dioleoyl(DOPC), palmitoylarachidonoyl (PAPC), and palmitoyloleoyl (POPC)] in r-HDL was also investigated. In discoidal r-HDL, we found that POPC >/= DOPC = PAPC/DPPC. However, in LCAT-treated spheroidal r-HDL, POPC = DOPC > PAPC/DPPC. In both discoidal and spheroidal rHDL, DPPC containing r-HDL were not hydrolyzed to a significant extent. Collectively, these studies demonstrate that the physico-chemical properties of particles (such as phospholipid packing and phospholipid acyl composition) play a significant role in hydrolysis of HDL phospholipid by HL and, therefore, in reverse cholesterol transport.  相似文献   
83.
BACKGROUND: Nasopharyngeal carcinoma (NPC) is a prevalent malignant tumor among Southern Chinese. Previously, the authors described the prognostic significance of a serum antibody assay to a recombinant Epstein-Barr virus Bam HI-Z replication activator protein (ZEBRA) in NPC patients with long term follow-up. In this study, the authors further reported the use of DNA flow cytometry (DNA-FCM) as an additional technique for determining the prognosis of NPC patients in the same series. METHODS: One hundred and forty-three archival biopsies from 110 NPC patients were deparaffinized and subjected to DNA-FCM analysis. DNA ploidy state and various proliferative indices (PI) of the tumors were correlated with patient survival and frequency of recurrence. RESULTS: Among the biopsies analyzed, 119 were histologically positive NPC and 24 were negative. Fifty-one tumor biopsies that fulfilled the guideline criteria of the DNA Cytometry Consensus Conference were correlated with the clinical manifestations of the patients. Among them, 43 tumors (84%) were DNA diploid and 8 (16%) were aneuploid. Two PI, S-phase fraction (SPF) and proliferation fraction (PF), appear to be potentially useful prognostic indicators. For example, PF in patients who developed locoregional recurrence (15.1%) and distant recurrence (16.4%) after radiation therapy both were significantly higher than PF in patients who were in complete remission (8.2%) (P = 0.0005 and P = 0.004, respectively). Significant differences in SPF between patients with distant recurrence (10.6%) and those in remission (5.7%) also was found (P = 0.005). Using Kaplan-Meier analysis, patients with high PF, high SPF, and aneuploid tumors had significantly poorer 12-year survival rates (35%, 26%, and 28%, respectively) than those patients with low PF, low SPF, and diploid tumors (77%, 67%, and 59%, respectively) (P < 0.0009, P < 0.004, and P < 0.01, respectively). CONCLUSIONS: Determination of tumor PI and DNA ploidy state by DNA-FCM at diagnosis of NPC can be potentially useful in selecting a poor prognostic subgroup of NPC patients. These parameters may enable oncologists to plan for more stringent treatment strategies such as hyperfractionated and accelerated radiation therapy or concomitant chemoradiotherapy for these patients.  相似文献   
84.
Primary benign intracardiac tumours in the infant period are rare. We report a case of a cardiac osteoma detected at 17 weeks of gestation. Ultrasonographically, it appeared as a calcified mass with a sharp margin and was associated with hypoplastic right ventricle. The gross and histological findings are presented.  相似文献   
85.
Origins of neural crest cell diversity   总被引:1,自引:0,他引:1  
The effect of diets containing 50% of fat calories from butter, butter enriched with mono- and polyunsaturated fatty acids, and margarines with and without trans fatty acids on the serum lipids of 38 healthy men in a free-living condition have been determined. Serum lipid responses to the high level of individual dietary fats were unexpectedly small. The butter diet produced a small, but significant rise (5%) in the total serum cholesterol and low density lipoprotein (LDL)-cholesterol, relative to all other diets. Enrichment of butter with either olive oil (50/50) or sunflower oil (50/50) failed to reduce serum lipid levels below habitual diet values. Hard margarine, containing 29% trans fatty acids, caused a decrease in apolipoprotein A-I and B levels, but did not change total serum cholesterol or LDL-cholesterol levels, relative to habitual diet values. A soft margarine, high in linoleate, with no trans fatty acids reduced total cholesterol, LDL-cholesterol, and apolipoprotein B significantly, relative to all diets. Soft margarine high density lipoprotein (HDL)-cholesterol levels remained unchanged, but apolipoprotein A-I values were decreased relative to habitual and butter diets. The quantities of saturated fatty acids and the sum of monounsaturated and polyunsaturated fatty acids consumed on the hard and soft margarines were equal; therefore, the different response of serum cholesterol and LDL-cholesterol between these two diets is attributable to the trans fatty acids in the hard margarine. The data indicate that trans fatty acids are not metabolically equivalent to the natural cis isomers and that they affect the serum lipid profile adversely.  相似文献   
86.
Previous epidemiologic studies of poisonings in Hong Kong are regional hospital-or poison information center-based and have focused on either adults or children. This paper reports on the territory-wide hospitalization and mortality rates, comparing medicinal and non-medicinal poisonings in the general population. Between 1980 and 1995, the figures for hospitalizations and mortality due to medicinal (ICD codes 960-977) or non-medicinal (ICD codes 980-989) poisonings were obtained from the Annual Reports of the Department of Health, Hong Kong Government. Rates of medicinal poisonings increased between 1980/81 (57.3/100,000) and 1987/88 (80.9/100,000), but then declined (59.1/100,000) in 1993/94. Rates of non-medicinal poisonings were rather static (49-53/100,000) between 1980/81 and 1988/89, but then declined (22.0/100,000) in 1994/95. Between 1980/81 and 1988/89, rates of fatal medicinal poisonings (0.73-1.31/100,000) were similar to those of fatal non-medicinal poisonings (0.98-1.70/100,000). However, from 1989/90, there was an increase in the rates of fatal medicinal poisonings (1.94-2.80/100,000), although rates for non-medicinal poisonings remained much the same (0.80-1.38/100,000). Hospitalizations due to poisonings are now less common in Hong Kong than before, due largely to a greater decline in non-medicinal poisonings.  相似文献   
87.
Despite modern medical advances, the morbidity and mortality rates associated with spinal epidural abscess remain significant, and the diagnosis is elusive. The incidence of spinal epidural abscess is approximately one to two cases per 10,000 among all patients admitted to hospitals. The symptoms of spinal epidural abscess are varied but include lower back pain, fever, local tenderness and neurological deficit especially in such high risk groups as patients with diabetes, intravenous drug abuse, chronic renal failure, alcoholism, liver disease and immunocompromization. Accumulation of data is difficult in that many physicians will never see a case during their careers. Herein, we present a case with lower back pain associated with both lower legs weakness. His abdomenon CT revealed retroperitonium and right perirenal abscess. External drainage as well as antibiotic treatment was done immediately. However, the lower legs weakness became severe and a lumbar spine MRI revealed T11-L4 epidural abscesses and L2-3 intervertebral space pus formation. Then, the patient was transfered to our Neurosurgical Ward for further treatment. His postoperative condition improved in both lower legs. This case report is to enhance the recognition and treatment of spinal epidural abscess, a rare affliction.  相似文献   
88.
The purpose of this study was to evaluate the prenatal characteristics of congenital nephrosis of the Finnish type (CNF). Patients presenting with elevated maternal serum and/or amniotic fluid alpha-fetoprotein levels, normal ultrasound examinations and normal fetal karyotypes were included. A retrospective cohort study was conducted using questionnaires sent to all board certified clinical geneticists. Perinatal outcome, including histologic verification of CNF, was obtained. Forty index cases met the above criteria. Ten cases ultimately did not have the diagnosis of CNF, with a median MSAFP level of 7.59 MoM (range 2.7-27.64 MoM) and a median AFAFP level of 10.99 MoM (range 1.47-128.6 MoM). In the affected cohort of index pregnancies, the initial median MSAFP level was 14.49 MoM (range 3.1-38.0 MoM); the median AFAFP level was 40.0 MoM (range 2.4-80.9). MSAFP and AFAFP levels may be lower than previously recognized in patients carrying fetuses with CNF. There is significant overlap between the affected and unaffected patients.  相似文献   
89.
90.
TY 《网络与信息》2009,23(9):15-15
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