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排序方式: 共有319条查询结果,搜索用时 15 毫秒
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This study was designed to examine serum lipid profile and blood pressure in relation to age and sexual maturity. Written informed consent to participate was obtained from 42% of the eligible population of two Devon communities. The blood pressure of 343 boys and 336 girls, aged 11-16 years, was recorded and sufficient blood for analysis was obtained from 320 boys and 301 girls. Of these, sexual maturity of 221 boys and 209 girls was visually assessed using the indices developed by Tanner. In girls there was a significant (p less than 0.05) correlation between age and serum triglyceride level (r = 0.16) and in boys both serum cholesterol and HDL-cholesterol were significantly (p less than 0.01) and negatively correlated with age (r = -0.25 and -0.18 respectively). Girls had significantly higher (p less than 0.05) levels of HDL-cholesterol than boys but neither sex demonstrated significant changes (p greater than 0.05) in serum lipids or lipoproteins with sexual maturity. No significant differences (p greater than 0.05) were detected between the mean diastolic blood pressures of boys and girls but older boys had significantly higher (p less than 0.05) systolic blood pressures than similarly aged girls. Age was positively and significantly correlated (p less than 0.01) with blood pressure in both boys (systolic, r = 0.49; diastolic, r = 0.30) and girls (systolic, r = 0.28; diastolic, r = 0.29). More mature children were demonstrated to have both higher systolic and diastolic blood pressures than less mature children (p less than 0.05) but when allowance was made for school year group through analysis of co-variance the relationship for diastolic blood pressure in boys no longer remained significant. Blood pressures observed in this study do not raise general cause for concern but the data indicate that unfavourable serum lipid and lipoprotein profiles are common. 相似文献
3.
The presence of checkpoint mechanisms which are able to recognize damaged
chromatin and thereafter to prevent exit from metaphase I has been
investigated in giant mouse oocytes produced by fusion of a normal
metaphase I oocyte with an equivalent oocyte with damaged chromatin. The
presence of damaged chromatin did not prevent the onset of anaphase I in
both sets of chromatin in the fused cells. Interestingly, fused or unfused
cells containing only damaged chromatin failed to enter anaphase and
persisted instead in a metaphase-like state. These results demonstrate the
fragility of checkpoint controls in mammalian female germ cells.
相似文献
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Scleral remodeling during the development of and recovery from axial myopia in the tree shrew 总被引:32,自引:0,他引:32
PURPOSE: Recent investigations have suggested that scleral thinning in mammalian eyes with axial myopia is a consequence of the loss of scleral tissue, rather than the redistribution of existing tissue as the eye enlarges. The present study investigated whether further changes in the distribution and metabolism of scleral tissue occur during the process of recovery from axial myopia. Scleral glycosaminoglycan (GAG) synthesis and content as well as scleral dry weight changes were monitored as indicators of remodeling in myopic and recovering tree shrew sclerae. METHODS: Myopia was induced in tree shrews by monocularly depriving them of pattern vision. Some animals then had the occluder removed and were allowed to recover from the induced myopia for periods of 1, 3, 5, 7, and 9 days. Newly synthesized GAGs were radiolabeled in vivo with [(35)S]sulfate. Sulfate incorporation and total GAG content in the sclera was measured through selective precipitation of GAGs from proteinase K digests with alcian blue dye. Dry weights of the sclerae were also determined. Changes in ocular refraction and eye size were monitored using retinoscopy, keratometry, and ultrasonography. RESULTS: Eyes developing myopia showed a significant reduction in scleral GAG synthesis, particularly in the region of the posterior pole (-36% +/- 7%) compared with contralateral control eyes. Scleral dry weight was also significantly reduced in these eyes (-3.7% +/- 1.2%). In recovering eyes, significant changes in GAG synthesis were apparent after 24 hours of recovery. After 3 days of recovery, significantly elevated levels of GAG synthesis were found (+79% +/- 15%), returning to contralateral control eye values after 9 days of recovery. Interocular differences in scleral dry weight were shown to follow a similar pattern to that observed for GAG synthesis. CONCLUSIONS: Active remodeling, resulting in either the loss or replacement of scleral tissue and not passive redistribution of scleral tissue, is associated with changes in eye size during both myopia development and recovery. Regulatory changes in scleral metabolism can be rapidly evoked by a change in visual conditions and the direction of regulation is related to the direction of change in eye size. 相似文献
6.
Changes in eye size during the development of refractive error are accompanied by alterations in scleral biochemistry in both humans and animal models of myopia. This review discusses more recent data on scleral changes in mammalian models of myopia and considers the role of visual information in the control of scleral matrix biology. These visually-driven changes in scleral biochemistry are placed in the context of both the emmetropisation process and the abnormal enlargement of the eye that is characteristic of human high myopia. 相似文献
7.
Gentle Sunder Shrestha Pankaj Joshi Santosh Chhetri Ragesh Karn Subhash Prasad Acharya 《Indian Journal of Critical Care Medicine》2015,19(5):283-285
Refractory and super-refractory status epilepticus is a life-threatening neurological emergency, associated with high morbidity and mortality. Treatment should be aimed to stop seizure and to avoid cerebral damage and another morbidity. Published data about effectiveness, safety and outcome of various therapies and treatment approaches are sparse and are mainly based on small case series and retrospective data. Here we report successful management of two cases of super-refractory status epilepticus refractory to anesthetic therapy with midazolam and complicated by septic shock, managed successfully with ketamine infusion. 相似文献
8.
NL Vasukutty RG Middleton P Young C Uzoigwe B Barkham S Yusoff THA Minhas 《Annals of the Royal College of Surgeons of England》2014,96(8):597-601
IntroductionDislocation following total hip replacement continues to be a problem for which no completely satisfactory solution has been found. Several methods have been proposed to reduce the incidence of hip dislocations with varying degrees of success, including elevated rim liners, constrained liners and large diameter bearings. We present our experience with the double mobility acetabular component in patients at high risk of instability.MethodsThis was a retrospective review of 65 primary total hip arthroplasties in 55 patients (15 men, 40 women), performed between October 2005 and November 2009. The majority (80%) of patients had at least two and 26% had at least three risk factors for instability. The mean age was 76 years (range: 44–92 years). The patients were followed up for a mean duration of 60 months (range: 36–85 months).ResultsFourteen patients died and one was lost to follow-up, leaving fifty hips for final assessment. Until the final follow-up appointment, no patients had dislocation and none required revision surgery. The mean Oxford hip score improved from 45.0 to 26.5 (p<0.0001). The mean Merle d’Aubigné pain score improved from 1.4 to 4.9 (p<0.0001), the walking score from 2.3 to 3.1 (p<0.07) and the absolute hip function score from 5.4 to 10.8 (p<0.0001). There were no clinical or radiographic signs of loosening.ConclusionsThe double mobility acetabular component was successful at preventing dislocation during early to medium-term follow-up. However, as data are still lacking with regard to polyethylene wear rates at the additional bearing surface, it would be prudent to restrict the use of this implant to selected patients at high risk of instability. 相似文献
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Evaluation of atypical human immunodeficiency virus immunoblot reactivity in blood donors 总被引:6,自引:0,他引:6
NL Dock ; HV Lamberson Jr ; TA O''Brien ; DE Tribe ; SS Alexander ; BJ Poiesz 《Transfusion》1988,28(5):412-418
Blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (HIV) who showed atypical patterns of viral core protein reactivity on Western blot were monitored for several months. Characterization of their antibodies was performed by 1) use of recombinant HIV proteins; 2) determination of cross-reactivity to HTLV-I, HTLV-II, and HTLV-IV: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. Nineteen of 20 donors maintained the same HIV antibody reactivity throughout the follow-up period; the other donor became fully antibody-positive. Eighteen of 20 donors' sera showed clear reactivity with HIV recombinant core proteins. Ten of 19 donor samples demonstrated cross-reactivity to HTLV-IV; 3 of these 10 also cross-reacted with HTLV-I. The immune status of all donors was normal, although the medical histories and HLA antibody screens suggested possible autoimmune reactivity in 9 of 18 donors. During follow-up interviews, three donors reported possible risk factors for HIV infection that had not been acknowledged at the time of blood donation. We conclude that exclusion of donors with these atypical serologic test results is warranted while further studies to determine significance are being conducted. 相似文献