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31.
This study examined the relationship of 16 variables with homicide, suicide, and unintentional firearm deaths. This cross-sectional analysis, using adjusted partial correlation coefficients, found that state-level firearm homicide rates significantly varied by the prevalence of firearms and by percent of the population which was African American. Whereas, state-level variations in firearm suicide mortality significantly varied by firearm prevalence, per capita alcohol consumption, percent of the population which was African American, and level of urbanization. None of the variables were significantly (p < or = .05) related to state-level variations in unintentional firearm mortality. Furthermore, state gun laws had only a limited effect on firearm-related homicide deaths. Although the current study cannot determine causation, firearm mortality in its various forms is most commonly related to the prevalence of firearms and the percent of the population that is African American.  相似文献   
32.
Morphine's analgesic actions are thought to be mediated through both the central and peripheral nervous systems. L-type calcium channel blockers have been reported to potentiate the analgesic effects of morphine, but the locus of this interaction is not known. In this experiment, we examined the site of verapamil-induced potentiation of morphine analgesia in mice using the quaternary opioid receptor antagonist naloxone-methiodide (NLX-M). Subcutaneous injections of morphine increased locomotor activity and serum corticosterone level, which are mediated by the central nervous system. These central effects were not antagonized by 0.1 mg/kg of NLX-M, whereas this dose of NLX-M partially antagonized the analgesic effect of morphine. Treatment with verapamil potentiated morphine analgesia in a dose-dependent manner. The verapamil-induced potentiation of morphine analgesia was abolished by pretreatment with NLX-M (0.1 and 1 mg/kg). These findings suggest that peripheral mechanisms partially contribute to morphine analgesia and mediate the potentiation of morphine analgesia by verapamil.  相似文献   
33.
Self-care is gradually being recognized as important in the treatment of pollinosis, based up to now on data on airborne pollen. To determine the real-time numbers of airborne pollen would be more useful in self-care, however, so we studied the usefulness of the real-time pollen counter. Between Feb. 2, 2001, and Apr. 26, 2001, 4 types of airborne pollen i.e., Japanese cedar, Japanese cypress, black alder, and beech observed in Wakayama City were counted with a Durham pollen counter and a real-time pollen counter (Yamato Manufacturing Co. Ltd.). Correlation between the 2 pollen counters was r = 0.69 for Japanese cedar in March and r = 0.89 for Japanese cypress in April. A high correlation was observed between outcomes of the 2 pollen counters. The amount of pollen from black alder and beech was less than that from Japanese cedar and cypress. Unexpected peaks were observed not related to the pollen number is apparently due to snow. We have taken measure against snow, so we concluded that the real-time pollen counter was useful in counting the amount of airborne pollen over time.  相似文献   
34.
A newborn hearing screening was conducted on 319 neonatal intensive care unit (NICU) and 1200 well-born nursery (WBN) infants. Mean NICU birth weight was 1997 g and mean gestational age 34 weeks. Auditory brainstem response was studied in screening in NICU infants. Otoacoustic emission (OAE) or automated auditory brainstem response (AABR) was used in primary WBN screening. All infants not bilaterally passing hearing screening before discharge were recalled for outpatient retesting. If the outcome was still failure, ABR screening was conducted. The prevalence of infants diagnosed with hearing loss was 1.1% (16 of 1519). Of these 16, 75% were from the NICU and 75% were at risk for hearing loss. Mean age at hearing loss identification was 12.9 weeks in the WBN and mean age at hearing aid fitting was 16.1 weeks. Mean age at hearing aid fitting was lower for WBN than for NICU infants. Hearing loss identification and hearing aid fitting are thus feasible in NICU and WBN infants in universal newborn hearing screening.  相似文献   
35.
36.
In Japan, the number of households who have pets has gradually increased, together with the number of people who have pet allergies. Many reports exist on pollen and mite allergy, but few on pet allergy. We conducted an epidemic study in 531 first-year junior high school students in Wakayama prefecture in 1999. Questionnaires covered allergy and measurement of total IgE antibody using CAP system (Pharmacia Co. Ltd.) and specific IgE antibody using MAST26 system (Hitachi chemical Co. Ltd.). Of 306 students having pets, 11 were allergic to dogs, 11 to cats, 8 to both, and 1 to rabbits. Clinical symptoms were various. No differences in symptoms were observed among allergens. Serum total IgE tended to increase in students who suffered from pet allergies. Positive rates of specific IgE antibodies were high in mites and Japanese cedar pollen (36.7% for mites and 37.0% for Japanese cedar pollen), and also in dogs and cats (15.4% for dogs and 18.2% for cats). Specific dog and cat IgE antibodies increased significantly (p = 0.033 for dog and for p < 0.0001 cat), but no significant correlation was found between the positive specific IgE antibody and history of pet keeping.  相似文献   
37.
The nature and extent of bullying at school   总被引:2,自引:0,他引:2  
In elementary schools, the prevalence of bullying ranges from 11.3% in Finland to 49.8% in Ireland. The only United States study of elementary students found that 19% were bullied. Bullying behavior declines as students progress through the grades. School bullying is associated with numerous physical, mental, and social detriments. A relationship also exists between student bullying behavior and school issues such as academic achievement, school bonding, and absenteeism. Prevention of school bullying should become a priority issue for schools. The most effective methods of bullying reduction involve a whole school approach. This method includes assessing the problem, planning school conference days, providing better supervision at recess, forming a bullying prevention coordinating group, encouraging parent-teacher meetings, establishing classroom rules against bullying, holding classroom meetings about bullying, requiring talks with the bullies and victims, and scheduling talks with the parents of involved students. Finally, this review suggests further studies needed to help ameliorate the bullying problem in US schools.  相似文献   
38.
39.
Insulin-like growth factor (IGF) binding proteins (IGFBP) were purified from conditioned media of cultured bovine endothelial cells (ECBP) and from human amniotic fluid (IGFBP-1), and then labeled by radioiodination. 125I-ECBP and 125I-IGFBP-1 were perfused through isolated beating rat hearts for 1 and 5 min, and the hearts fixed and analyzed for 125I-BP content and distribution. One to 4% of the perfused 125I-ECBP and 125I-IGFBP-1 crossed the capillary boundary. The ECBPs predominantly localized as intact 125I-BP in connective tissue elements of the heart with less 125I-BP in cardiac muscle. The ratio of 125I-ECBP in connective tissue: muscle (normalized to percent vol of these compartments) was greater than or equal to 10:1. In contrast, the IGFBP-1 had a greater affinity for cardiac muscle with ratios of 125I-IGFBP-1 in connective tissue:muscle of approximately 1:2. When 125I-IGF-I, in the absence of any BPs, was perfused through the hearts approximately 3-5% left the microcirculation and was found in subendothelial tissues. 125I-IGF-I localized primarily to cardiac muscle with a distribution of connective tissue:cardiac muscle of about 1:3. The findings in the isolated perfused heart were confirmed in intact animals. After 125I-IGFBP-1 was injected into anesthetized rats and allowed to circulate for 5 min, substantial radioactivity was associated with the heart. As in the isolated heart, the IGFBP-1 preferentially localized to cardiac muscle with a connective tissue:cardiac muscle ratio of 1:3. We conclude that IGFBPs produced by endothelial cells and the IGFBP-1 contained in amniotic fluid can cross the capillary boundaries of the rat heart, and that the ECBPs preferentially localize in connective tissue elements of the myocardium, whereas IGFBP-1 predominantly localizes in cardiac muscle.  相似文献   
40.
It is a challenge to understand the discrete roles of each point mutation in viral evolution, but overlapping genes provide an excellent entrance for the investigation of this complicated process. We obtained 132 sequences from the largest overlapping region in the HBV genome. Based on the genetic divergence between genotypes B and C, we distinguished a set of related footprint mutations that are believed to be responsible for historical selection events. Examining the mutations in the functional domains, we found that the virus has adopted a coherent strategy in its evolutionary process that can be summarized as follows: (1) the distribution of mutations was non-random throughout the overlapping region, and more mutations were preserved in the sequence when one of the genes was under relaxed selection; (2) the viral domains were subject to different selective pressures; for instance, the PreS1 domain underwent a strict selection, whereas the overlapped Spacer domain was relatively relaxed with obvious tolerance of non-synonymous mutations with a high dN/dS ratio; (3) different selective pressures on two codon sites ultimately determined that every mutation persevered at a proper position. Taken together, the functional constraints of protein domains are believed to be primarily responsible for the different selection patterns exhibited by the distribution of mutations and amino acid changes in the region where overlapping genes reside.  相似文献   
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