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51.
52.
Fabian SL Yii 《Ophthalmic & physiological optics》2023,43(6):1412-1418
Purpose
To compare axial length (AL) growth curves in East Asian (EA) and non-EA emmetropes.Methods
A meta-regression of 28 studies with emmetrope-specific AL data (measured with optical biometry) was performed. Emmetropia was defined as spherical equivalent refraction (SER) between −0.50 and +1.25 D, determined under cycloplegia if the mean age was ≤20 years. The AL growth curve (mean AL vs. mean age) was first fitted to the full dataset using a weighted nonlinear mixed-effects model, before refitting the model with ethnicity as a two-level grouping variable (EA vs. non-EA). Ethnic differences in growth curve parameters were tested using the Wald test.Results
A total of 3331 EA and 1071 non-EA emmetropes (mean age: 6.5–23.1 years) were included. There was no evidence of an ethnic difference in either final AL (difference: 0.15 mm, 95% CI: −0.04 to 0.35 mm, p = 0.15) or initial AL, as represented by the amount that the final AL needed to be offset to obtain the y-intercept (difference: −2.77 mm, 95% CI: −10.97 to 5.44, p = 0.51). Likewise, AL growth rate (curve steepness) did not differ between ethnic groups (difference: 0.09, 95% CI: −0.13 to 0.31, p = 0.43). Collectively, AL growth rate decreased from 0.24 mm/year at 6 years of age to around 0.05 mm/year at 11 years of age, after which it dipped below the repeatability of optical biometry (±0.04 mm) and practically plateaued around 16 years of age (final AL: 23.60 mm).Conclusions
EA and non-EA emmetropes have comparable AL growth curves. 相似文献53.
BACKGROUND: Growing interest is nowadays focused on the quality of life of
elderly people who survive with chronic diseases. Coronary heart disease
(CHD) is one of the most common diseases among the elderly and may have an
unfavourable impact on the patient's emotional well-being. OBJECTIVES: We
aimed to describe the prevalence of depression and the occurrence of
depressive symptoms among elderly CHD patients, with a special emphasis on
the relations between depression and the severity of CHD, and to find out
the possible association between CHD and depression. METHODS: The study was
carried out at the health centre of the municipality of Lieto, in
south-west Finland. The study population consisted of 488
community-dwelling men and 708 women, over 64 years old, from among whom
the participants with CHD (89 men and 73 women) were selected, and for whom
178 male and 146 female sex- and age- matched controls (free of CHD) were
drawn from the population. CHD patients were selected on the basis of the
presence of angina pectoris or a past myocardial infarction. Depressive
symptoms were measured with the Zung Self-rating Depression Scale.
Depression was described in relation to the severity of dyspnoea and chest
pain among patients. The associations between depression and age, health,
health behaviour, drugs, functional ability and social, psychosocial and
environmental factors were analysed by logistic regression analyses.
RESULTS: The prevalence of depression was 29% among male patients and 20%
among female patients. Depression was significantly more common among male
CHD patients than among male controls (P = 0.011). Among women, depression
was not associated with CHD. Earlier, depression had gone undiagnosed among
many CHD patients and controls, especially male patients. Among male CHD
patients, depression was associated with more severe dyspnoea, but no
similar association was found among female CHD patients. Among men the
occurrence of CHD, physical disability, widowhood or divorce, and among
women previous clinical depression, physical disability and the use of
angiotensin-converting enzyme (ACE) inhibitors, were associated with
depression. CONCLUSION: Depression is common among patients with CHD. It
seems that CHD is not an independent factor in the aetiology of depression
among the elderly. The association of CHD with depression among men is
explained by the acute or chronic psychic stress caused by CHD. It may be
that the more complicated the patient's CHD, the more probable is the
presence of depression.
相似文献
54.
Ramey C Youngblood Marcus McGee Jean M Feugang Scott T Willard Peter L Ryan 《International journal of medical sciences》2014,11(6):545-553
Background: Vascular endothelial growth factor (VEGF) is essential for normal vascular growth and development during wound repair. VEGF is estrogen responsive and capable of regulating its own receptor, vascular endothelial growth factor receptor-2 (VEGFR-2). Several agricultural pesticides (e.g., methoxychlor) have estrogenic potential that can initiate inappropriate physiological responses in estrogenic-sensitive tissues following exposure in vivo. Thus, the current study was designed to determine whether the VEGFR-2-Luciferase (Luc) reporter transgenic mouse is a useful model for evaluating estrogenic tendencies of methoxychlor by monitoring wound healing via VEGFR-2-mediated gene expression using bioluminescence and real-time imaging technology.Results: VEGFR-2-Luc gene activity peaked by d 7 (P<0.001) in all groups but was not different (P>0.05) between control and estrogen/methoxychlor exposed mice.Conclusions: Changes in VEGFR-2-Luc gene activity associated with the dermal wound healing process were able to be measured via photonic emission. The increase in vasculature recruitment and formation is paralleled by the increase of VEGFR-2-Luc activity with a peak on day 7. However, estrogen/methoxychlor did not significantly alter wound healing mediated VEGFR-2-Luc gene expression patterns compared to controls. This suggests that the VEGFR-2-Luc transgenic mouse wound model tested in this study may not be optimal for use as a screen for the angiogenic potential of estrogenic compounds. 相似文献
55.
Andrew M. Ramey John M. Pearce Andrew B. Reeves J. Christian Franson Margaret R. Petersen Hon S. Ip 《Archives of virology》2011,156(10):1813-1821
Avian influenza virus (AIV) prevalence and sequence data were analyzed for Steller’s eiders (Polysticta stelleri) to assess the role of this species in transporting virus genes between continents and maintaining a regional viral reservoir with sympatric northern pintails (Anas acuta). AIV prevalence was 0.2% at Izembek Lagoon and 3.9% at Nelson Lagoon for Steller’s eiders and 11.2% for northern pintails at Izembek Lagoon. Phylogenetic analysis of 13 AIVs from Steller’s eiders revealed that 4.9% of genes were of Eurasian origin. Seven subtypes were detected, including two also observed in northern pintails. No AIV strains were highly similar (> 99%) at all gene segments between species; however, highly similar individual genes were detected. The proportion of highly similar genes was greater within rather than between species. Steller’s eiders likely transport AIV genes between continents through long-distance migratory movements. Differences in AIV prevalence, subtype distribution, and the proportion of highly similar genes suggest limited AIV exchange between Steller’s eiders and northern pintails at Alaska Peninsula coastal lagoons during autumn. 相似文献
56.
Retroviral transduction and expression of the human alkyltransferase cDNA provides nitrosourea resistance to hematopoietic cells 总被引:4,自引:2,他引:4
Myelosuppression is the dose-limiting toxicity for nitrosourea chemotherapy. This toxicity predominantly involves modification of the O6 position of guanine with an alkyl moiety. The enzyme responsible for repair of O6-alkylguanine adducts, O6-alkylguanine-DNA alkyltransferase (alkyltransferase), is expressed at low levels in bone marrow (BM) cells. High alkyltransferase expression prevents the cytotoxicity and carcinogenicity of nitrosoureas in several transgenic and in vitro gene transfer models. We used gene transfer using a novel myeloproliferative sarcoma virus (MPSV) based retrovirus (vM5MGMT) to express the human alkyltransferase cDNA (MGMT) in human and murine hematopoietic cells. Transduced K562 cells had very high levels of alkyltransferase expression and significantly increased resistance to 1,3-bis (2- chloroethyl) nitrosourea (BCNU) as compared with untransduced K562 cells. Primary murine BM progenitors showed a high transduction efficiency with vM5MGMT and have increased BCNU resistance in vitro. After BM transplantation with vM5MGMT-transduced BM cells and BCNU treatment of these mice, BM, spleen and thymus had a 10- to 40-fold increase in alkyltransferase expression that persisted for at least 23 weeks posttransplantation. Progenitor cells procured from mice expressing high levels of alkyltransferase also had increased resistance to BCNU. Thus, an MPSV-based retroviral vector transduces mouse and human hematopoietic cells at high efficiency and results in high levels of gene expression both in vitro and in vivo. Overexpression of the alkyltransferase protein may protect hematopoietic progenitors from nitrosourea-induced myelosuppression. 相似文献
57.
58.
大肠癌免疫组化表达与临床病理的关系 总被引:1,自引:0,他引:1
目的:探讨大肠癌CEA、P53、nm23、Ki-67、MRP免疫组化表达特点和相互关系,及其与临床病理的关系.方法:回顾性分析2003-01/2006-07我院收治的73例大肠癌患者的临床病理及随访资料,并对其石蜡标本采用免疫组化SP染色法检测CEA、P53、nm23、Ki-67、MRP,分析其免疫组化特点及其与临床病理之间的关系.结果:CEA、P53、nm23、Ki-67、MRP在大肠癌中的阳性表达率依次为82.2%、68.5%、75.3%、84.9%和64.4%.CEA、MRP与大肠癌患者的各因素无统计学差异.P53、Ki-67和nm23与肿瘤的Dukes分期和淋巴结转移有关, P53、Ki-67在Dukes C、D期的阳性表达率(依次为82.8%和100%1明显高于Dukes A、B期者(59.1%和75.0%)(P<0.05),而nm23在Dukes C、D期的阳性表达率(58.6%)明显低于Dukes A、B期者(86.4%)(P<0.05).CEA与nm23的表达呈明显的负相关(r=-0.296,P=0.011),而P53和Ki-67表达之间呈现明显的正相关(r= 0.308,P=0.008),其他各指标间的表达无相关性.nm23、P53和Ki-67与预后因素关系明显,nm23在生存期≥3 a患者的阳性表达率(92.9%)高于生存期<3 a者(71.2%)(P<0.05),而P53和Ki-67在生存期≥3 a患者的阳性表达率(依次为42.9%和64.3%)明显低于生存期<3 a者(74.6%和89.8%)(P<0.05).结论:P53、Ki-67和nm23的表达与大肠癌的侵袭转移和预后密切相关.CEA可能是大肠癌的侵袭转移的促进因素.MRP所引起的耐药机制是一个相对独立的机制.CEA、P53、nm23、Ki-67可作为判断大肠癌恶性程度、侵袭转移以及预后的指标. 相似文献
59.
Allergic and nonallergic reactions to nitroglycerin occur. The aims of this study were to review the different manifestations of nitroglycerin allergy, to explain how to evaluate for it, and to discuss its treatment. We reviewed relevant literature in peer-reviewed journals, computerized databases, and references identified from relevant bibliographics. Nitroglycerin's most common side effects are headache, facial flushing, head throbbing, fainting, hypotension, tachycardia, and syncope. The majority of reported skin reactions to topical and transdermal nitroglycerin products are irritant contact dermatitis, allergic contact dermatitis, and urticaria. Five cases of presumed allergic reactions to oral, sublingual, intravenous, or perianal nitroglycerin products have been described. Patch testing may be helpful in subjects with skin reactions to topical or transdermal nitroglycerin. In subjects with positive patch tests to nitroglycerin (allergic contact dermatitis), transdermal nitroglycerin patches and other topical nitroglycerin products should be avoided. Most patients with contact dermatitis to nitroglycerin have tolerated oral nitroglycerin, sublingual nitroglycerin, or oral isosorbide challenges. 相似文献
60.
Brault AC Langevin SA Ramey WN Fang Y Beasley DW Barker CM Sanders TA Reisen WK Barrett AD Bowen RA 《The American journal of tropical medicine and hygiene》2011,85(4):758-767
A West Nile virus (WNV) isolate from Mexico (TM171-03) and BIRD1153, a unique genotype from Texas, have exhibited reduced murine neuroinvasive phenotypes. To determine if murine neuroinvasive capacity equates to avian virulence potential, American crow (Corvus brachyrhynchos) and house sparrows (Passer domesticus) were experimentally inoculated with representative murine neuroinvasive/non-neuroinvasive strains. In both avian species, a plaque variant from Mexico that was E-glycosylation competent produced higher viremias than an E-glycosylation-incompetent variant, indicating the potential importance of E-glycosylation for avian replication. The murine non-neuroinvasive BIRD1153 strain was significantly attenuated in American crows but not house sparrows when compared with the murine neuroinvasive Texas strain. Despite the loss of murine neuroinvasive properties of nonglycosylated variants from Mexico, our data indicate avian replication potential of these strains and that unique WNV virulence characteristics exist between murine and avian models. The implications of reduced avian replication of variants from Mexico for restricted WNV transmission in Latin America is discussed. 相似文献