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11.
Mock CN Abantanga F Cummings P Koepsell TD 《Bulletin of the World Health Organization》1999,77(12):955-964
Injury is an increasingly significant health problem in most low-income countries. However, strategies for preventing injury have not been well addressed. The present study was carried out to measure the incidence and outcome of various mechanisms of injury in Ghana in order to provide data for use in developing priorities for injury prevention efforts. For this purpose, using two-stage cluster sampling and household interviews, we surveyed 21,105 persons living in 431 urban and rural sites. During the preceding year, 1609 injuries resulting in one or more days of loss of normal activity were reported. Injury-related mortality was slightly higher in the urban (83 per 100,000) than in the rural area (53 per 100,000). However, the burden of disability from nonfatal injuries, as assessed by disability days, was higher in the rural (4697 disability days per 1000 person-years) than in the urban area (2671 days per 1000 person-years). Based on incidence rates and disability times, the major types of injury in the urban area were transport-related injury and falls. In the rural area, agricultural injuries predominated, followed by falls and transport-related injury. In rural and urban areas combined, 73% of motor vehicle-related injuries involved commercial vehicles. In this and other similar developing-country settings, injury prevention efforts should focus on falls and on transport safety in both urban and rural areas, with special attention being paid to commercial vehicles. In rural areas, agricultural injuries contributed the largest burden of morbidity, and should be a priority for prevention efforts. 相似文献
12.
Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg
TPA) protocols were found to be under multigenic control. Eighty- one N2
mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were
either solidly resistant (no papillomas) or highly susceptible (> or = 7
papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite
markers to check for associations with susceptible and resistant
phenotypes. A locus on Chr 5 (Skts4) was found to control the
susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to
papilloma formation. In addition, higher than expected linkage scores were
seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is
required to establish whether genes determining papilloma formation are
located in these regions of the genome. In general, no evidence was seen
for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in
17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.
相似文献
13.
Bulger EM Arneson MA Mock CN Jurkovich GJ 《The Journal of trauma》2000,48(6):1040-6; discussion 1046-7
14.
Mock C MacKenzie E Jurkovich G Burgess A Cushing B deLateur B McAndrew M Morris J Swiontkowski M 《The Journal of trauma》2000,49(6):1002-1011
BACKGROUND: Factors influencing the progression of physical impairment to patient-perceived disability are not well known. We sought to better understand this relationship in the setting of injury. METHODS: We followed a cohort of 302 patients with lower extremity fractures over a 1-year period. Physical impairment was assessed by range of motion, strength, and pain. Range of motion and strength were assessed together as a proportion of normal function of the extremity (impairment score). Pain was assessed using a Visual Analogue Scale (VAS) pain score. Disability was assessed using the Sickness Impact Profile (SIP), a widely used measure of patient-perceived limitations of everyday activities attributable to illness. The SIP was administered during hospitalization to assess preinjury baseline. Impairment assessment and readministration of the SIP were performed at 12 months after injury. RESULTS: Impairment in leg function (range of motion and strength) was highly correlated (p < 0.001) with overall SIP score at 12 months, but accounted for only 23% of the variance in overall SIP scores. Likewise, VAS pain score was highly correlated (p < 0.001) with overall SIP score at 12 months, but accounted for only 29% of the variance in overall SIP scores. In a multivariate linear regression analysis, variables that were independently associated with overall SIP score included impairment score, VAS pain score, preinjury SIP, poverty status, education status, social support, having hired a lawyer, and involvement with workers' compensation. These variables accounted for 52% of the variance in overall SIP scores at 12 months. CONCLUSION: The degree of physical impairment accounts for only a small amount of the variance in disability from lower extremity fracture. Identifiable patient characteristics including age, socioeconomic status, preinjury health, and social support together with impairment account for over half of the variance in long-term disability. Further research is needed to increase understanding of other factors that influence the progression of impairment to disability, especially those factors that may be amenable to intervention. 相似文献
15.
Charles Mock 《World journal of surgery》2013,37(7):1457-1459
16.
Denison J. Kuruvilla John A. Widness Demet Nalbant Robert L. Schmidt Donald M. Mock Peter Veng-Pedersen 《The AAPS journal》2015,17(5):1246-1254
Fetal RBCs are produced during a period of very rapid growth and stimulated erythropoiesis under hypoxic intrauterine conditions. Fetal RBC life span varies with gestational age (GA) and is shorter than that in healthy adults. Due to the special kinetic properties of life span-based survival of human RBCs, a mathematical model-based kinetic analysis of the survival of fetal RBCs shortly after birth provides a unique opportunity to “look backward in time” to evaluate fetal erythropoiesis. This work introduces a novel method that utilizes postnatal in vivo RBC survival data collected within 2 days after birth to study both nonsteady-state (non-SS) in utero RBC production and changing fetal RBC life span over time. The effect of changes in erythropoiesis rate and RBC life span and the effect of multiple postnatal phlebotomies on the RBC survival curves were investigated using model-based simulations. This mathematical model, which considers both changes in the rate of erythropoiesis and RBC life span and which accurately accounts for the confounding effect of multiple phlebotomies, was applied to survival curves for biotin-labeled RBCs from ten anemic very low birth weight preterm infants. The estimated mean fetal RBC production rate scaled by body weight was 1.07 × 107 RBCs/day g, and the mean RBC life span at birth was 52.1 days; these values are consistent with reported values. The in utero RBC life span increased at a rate of 0.51 days per day of gestation. We conclude that the proposed mathematical model and its implementation provide a flexible framework to study in utero non-SS fetal erythropoiesis in newborn infants.KEY WORDS: cord blood RBCs, fetal erythropoiesis, fetal RBC life span, fetal RBC production, red blood cells 相似文献
17.
Hu DJ Subbarao S Vanichseni S Mock PA Ramos A Nguyen L Chaowanachan T Griensven Fv Choopanya K Mastro TD Tappero JW 《AIDS (London, England)》2005,19(3):303-308
OBJECTIVES: To estimate the frequency and incidence of dual HIV-1 subtype infections, including superinfections, among recent seroconvertors from a cohort of injection drug users (IDUs). METHODS: A total of 1209 HIV-negative IDUs were followed in a prospective cohort study at 15 methadone clinics in Bangkok, Thailand. After 2308 person-years (PY) of follow-up, 133 seroconverted to HIV-1, of which approximately 20% were subtype B and 80% were CRF01_AE (formerly called subtype E). Specimens from 126 individuals were available at time of first seropositive test and specimens from 80 of these 126 individuals were also available more than 12 months later. For each infected participant, we calculated the amount of time to superinfection, loss to follow-up, or to the closest visit more than 12 months after the time of initial seropositivity. RESULTS: Of all 126 seroconverters seen at the time of the first seropositive test result, there was no apparent case of concurrent dual subtype infection detected despite 2301 PY of observation. Overall, the incidence of superinfection was 2.2 per 100 PY [95% confidence interval (CI), 0.3-7.8]. The 1-year incidence of CRF01_AE superinfection following subtype B primary infection was 3.9 per 100 PY (95% CI, 0.1-21.9) and the incidence of subtype B superinfection following CRF01_AE primary infection was 1.5 per 100 PY (95% CI, 0.04-8.3). CONCLUSIONS: Determination of the frequency and incidence of dual HIV-1 subtype infection demonstrates that HIV-1 superinfection is not uncommon in a population with high HIV-1 incidence with more than one circulating strain. 相似文献
18.
Warunee Thienkrua Frits van Griensven Philip A. Mock Eileen F. Dunne Boonyos Raengsakulrach Wipas Wimonsate Nopporn Howteerakul Chaiwat Ungsedhapand Anupong Chiwarakorn Timothy H. Holtz 《AIDS and behavior》2018,22(7):2137-2146
High HIV incidence has been reported in young men who have sex with men (YMSM) in North America and Western Europe, but there are limited data from Southeast Asia suggesting MSM may be the driver of the HIV epidemic in this region. We described HIV incidence and risk factors among 494 YMSM enrolled in a cohort study in Bangkok, Thailand. The HIV incidence was 7.4 per 100 person-years. In multivariable analysis, reporting use of an erectile dysfunction drug in combination with club drugs, having receptive or both insertive and receptive anal intercourse with men, having hepatitis A infection, having rectal Chlamydia trachomatis, having hepatitis B infection prior to HIV seroconversion, and reporting not always using condoms with male steady partners were significantly associated with HIV incidence in YMSM. Reduction in new HIV infections in YMSM are critical to reach targets set by Thailand and the region. 相似文献
19.
Katherina N.-L. Flaig Steven E. Mock Joann P. Reinhardt 《European journal of ageing》2008,5(3):215-222
This study draws on an evolutionary model of exchange in relationships to examine the nature of perceived reciprocity in the
context of kin and non-kin relationships among a sample of visually impaired older adults (age 63–99). Further, we examined
the direct and moderating impact of functional impairment and adaptation to visual impairment on the nature of perceived reciprocity.
Results showed that the greater the degree of genetic relatedness the more imbalanced the exchange. It was also found that
degree of adaptation to visual impairment moderated the association between genetic relatedness and perceived exchange, such
that the greater the degree of genetic relatedness the more people reported they gave rather than received except at very
low levels of adaptation, when people received more than they gave the greater the degree of genetic relatedness. Thus, an
evolutionary model was supported such that imbalanced exchange was found more with greater degrees of genetic relatedness,
but the direction of exchange was different for high versus low levels of adaptation to vision impairment. 相似文献