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81.
I Emanuel H Filakti E Alberman S J Evans 《British journal of obstetrics and gynaecology》1992,99(10):836-840
OBJECTIVE: To ascertain whether maternal twinning influences the previously described association between the birthweight of singleton mothers and their infants. DESIGN AND SUBJECTS: The association between the birthweight of singleton parents and their offspring and that between twin parents and their offspring was compared using data from the 23-year-old sample of the 1958 British national birth cohort. The numbers available for full comparison were 1027 female and 611 male singleton cohort members, and 26 female and 17 male twin cohort members and their first singleton livebirths. RESULTS: Of the mothers who had been twins, half had been of low birthweight, and overall their mean weight was 700 g less than that of their singleton counterparts. Nevertheless, the mean birthweight of babies of twin mothers was 133 g, and of twin fathers 94 g, greater than of babies of corresponding singletons. For female, but not male, parents this difference persisted after adjustment for confounding variables. CONCLUSIONS: We suggest two possible reasons for the difference between the weight of babies of twin and singleton mothers. Firstly, the growth of twins becomes retarded late in pregnancy, possibly after a period critical in determining long-term reproductive effects. Secondly, the twin survivors were of higher birthweight than the original twin cohort, whilst the singleton survivors were more representative of all singleton births, thus introducing a possible bias. 相似文献
82.
The physiological, anthropometric, personality and lifestyle characteristics of 122 women volunteering for a seven-week program of heavy resistance weight training were studied relative to adherence rates. Initially, volunteers were above-average in body mass and grip strength, but were below-average in chest girth and bicristal diameter. They were also physically active and only 20% smoked. Regular (R) attenders (attendance greater than 80%; 72% of the sample) were physically smaller in terms of stature, mass, girths and dimensions, but had greater strength per kg of mass or LBM compared to participants classified as infrequent (I; 24-76%) and dropout (DO; less than 20%). Conversely, I and DO members were more likely to smoke, to smoke more heavily, to drink coffee and to not eat breakfast. Most dropouts quit during the first week; among volunteers who continued, differences in assigned training intensity had no effect on adherence. Adherence was also unrelated to strength gains, anthropometric adaptations, or injury. 相似文献
83.
C Lynn Van Antwerpen MD Sidney M Gospe Jr MD PhD Nancy A Wade MD 《Pediatric neurology》1988,4(6):379-380
A 12-year-old girl developed a reversible myeloradiculopathy 1 week after a wasp sting. Delayed neurologic hypersensitivity reactions to Hymenopteran stings occur primarily in adults. Reactions involving both the peripheral and central nervous systems are extremely rare and have never been reported in a child. The mechanisms underlying this uncommon reaction may be related to age-dependent differences in immunologic responses. 相似文献
84.
85.
Factors associated with hypertension in Nigerian civil servants 总被引:3,自引:0,他引:3
Clareann H. Bunker Ph.D. Flora A. Ukoli M.B.B.S. Martin U. Nwankwo M.B.B.S. Jackson A. Omene M.D. Glenn W. Currier M.D. Linda Holifield-Kennedy Donald T. Freeman Emanuel N. Vergis M.D. Lan Lan L. Yeh Ph.D. Lewis H. Kuller M.D. Dr.P.H. 《Preventive medicine》1992,21(6):710-722
BACKGROUND. Study of hypertension in segments of West African populations in transition toward Westernization may lead to better understanding of the high risk for hypertension among Westernized blacks. METHODS. Five hundred fifty-nine urban civil servants, ages 25-54, were recruited from six ministries of Bendel State, Nigeria. Blood pressure, physical measurements, urinary protein and glucose, fasting blood glucose, and demographic data were collected at the workplace. Subjects were classified as senior staff (professionals or administrators) or junior staff (non-administrators). RESULTS. Among 172 male senior staff, the age-adjusted rate of hypertension (diastolic blood pressure > or = 90 mm Hg, systolic blood pressure > or = 140 mm Hg, or on an antihypertensive medication) was 43% and occurrence rose dramatically from 21 to 63% across age groups 25-34 to 45-54, respectively. Among 266 male junior staff, the age-adjusted rate of hypertension was 23%, and occurrence did not rise with age. Logistic regression showed that body mass index (kg/m2), age, alcohol drinking, and being senior staff were all independently related to hypertension in men. On the other hand, the age-adjusted rate of hypertension in 121 women was 20% and was significantly related only to body mass index. CONCLUSION. Male urban civil servants appeared to have a risk for hypertension similar to that of U.S. black males. Age, body mass index, alcohol drinking, and other unidentified factors related to higher socioeconomic status were strong determinants of hypertension in this population. 相似文献
86.
Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
87.
C Santos D Diante A Baptista E Matediane C Bique P Bailey 《International journal of gynaecology and obstetrics》2006,94(2):190-201
OBJECTIVE: The 5-year project in the province of Sofala was designed to improve access, quality and utilization of emergency obstetric care (EmOC) by strengthening rural hospitals and health centers and ultimately the health system's capacity to respond to emergencies more quickly and effectively. METHODS: Implementation consisted of attention to infrastructure, human resource development, transportation and communication systems, and management. Specific management aspects that were targeted for improvement included: supportive supervision, logistics for supplies, equipment and drugs, record keeping, monitoring and evaluation, and quality improvement techniques such as maternal death audits. RESULTS: Access to EmOC improved with an increase in the number of fully functional EmOC facilities from 4 to 18. The number of women with obstetric complications who were admitted for treatment in participating facilities tripled, and the proportion of those women dying declined by half. CONCLUSIONS: Close collaboration and partnership with the provincial health directorate make the sustainability of many results likely while the replication of much of the Sofala model to other provinces is promising for the national strategy to reduce maternal mortality. 相似文献
88.
The human foot is a complex mechanical structure consisting of bones, ligaments and joints. They act together to provide a robust system capable of absorbing and dissipating the intermitted pressure that is subjected to its plantar surface during walking to prevent soft tissue breakdown. Current studies suggest that plantar foot pressure may lead to soft tissue breakdown (e.g. neuropathic ulceration) and hence research has so far concentrated on investigating the mechanical effects of plantar foot pressure on the foot’s integrity. This has been possible through the widely available pressure and force platforms as well as in-shoe pressure systems. However, to understand how plantar foot pressure causes soft tissue breakdown it is vital to investigate both the physiological–mechanical interactions between the skin and plantar foot pressure. This review suggests that with the current advances in technology, the physiological response of skin blood flow to mechanical plantar foot pressure should be investigated and correlated further, both during static and dynamic loading, by developing a new system capable of either measuring both variables simultaneously or by synchronising two systems in real time. 相似文献
89.
Comparison of pronator tenotomy and pronator rerouting in children with spastic cerebral palsy 总被引:1,自引:0,他引:1
Forty-one patients with cerebral palsy and pronation contracture of the forearm were treated with pronator teres rerouting compared with 16 patients who were treated with pronator teres tenotomy. The mean age of patients with pronator tenotomy was 4 years 3 months compared with 7 years 3 months for patients with rerouting. Follow-up averaged 94 months for tenotomy and 21 months for rerouting. Average gain in supination was 78 degrees for rerouting and 54 degrees for tenotomy. No patient lost active range of motion during follow-up. Although pronator teres tenotomy increased active supination of the forearm, greater active supination of the forearm was afforded patients treated with pronator teres rerouting. 相似文献
90.
Treatment of experimentally induced atherosclerosis in swine iliac arteries: A comparison of self-expanding and balloon-expanded stents 总被引:1,自引:0,他引:1
Chamaree Chuapetcharasopon Kenneth C. Wright Sidney Wallace Richard L. Dobben Cesare Gianturco 《Cardiovascular and interventional radiology》1992,15(3):143-150
Atherosclerosis was induced in 20 Hanford miniature swine. Subsequently, one iliac artery lesion in each of 16 pigs was stented
with either a self-expanding (8 pigs) or a balloon-expanded (8 pigs) stent. Immediately after stent placement, 4 animals in
each group were taken off the atherogenic diet and continued on normal chow for the remainder of the study. Four months after
stents were placed, atherosclerosis and the mural changes associated with the stent were more clearly evident in the arteries
of the pigs continued on the atherogenic diet. These pigs also exhibited significantly more neointimal proliferation. In addition,
the arteries containing the balloon-expanded stents showed more extensive and complex intimal changes when compared with arteries
with self-expanding stents. Although both stent designs were equally effective in maintaining vascular patency, the balloon-expanded
stent was more traumatic to the vessel wall which resulted in a significantly greater neointimal thickness. 相似文献