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31.
Krzysztof Kociski Marta Krenz‐Niedbaa Agnieszka Kozowska‐Rajewicz 《American journal of human biology》2004,16(1):31-42
This study investigated a hypothesis of dependence of child height and weight on the month of their birth. The sample comprised 1,241 subjects, 568 boys and 673 girls, age 6–20 years, from villages in Olsztyn Province, Northeast Poland. Individuals' height and weight data were standardized by sex and age to allow grouping of individuals born in the same month irrespective of their sex and age at examination. Subjects born in October to March proved to be significantly taller and heavier than those born in April to September. The magnitude of differences between the semiannual groupings equaled 13.1% of a standard deviation (SD) in height (P = 0.03) and 14.2% of SD in weight (P = 0.02). The month‐of‐birth effect was much stronger for children characterized by high socioeconomic status, where these differences amounted to 39.1% of SD in height (P = 0.02) and 49.4% of SD in weight (P = 0.01). There were no regular changes of the effect with age and no differences between the sexes were found. Fitted cosine functions identified the highest values of examined traits for individuals born in December with the lowest values being found in those born in June. Possible explanations of the month‐of‐birth effect are considered in terms of age categorizing, seasonal variety of growth rates, as well as birth‐related or conception‐related global, hemispheric, and local factors. This study rejects the first two possibilities and suggests this effect requires further research to be conducted in various geographical locations, climates, and cultures, on humans as well as on other species. Am. J. Hum. Biol. 16:31–42, 2004. © 2003 Wiley‐Liss, Inc. 相似文献
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C. A. Mangone E. M. Castaño E. Levy G. Abiusi T. Wisniewski M. R. Marques E. Faccio P. B. Gorelick B. Frangione and R. E. P. Sica 《Acta neurologica Scandinavica》1995,91(1):6-13
We report the clinical, SPET, immunohistochemical and DNA features of an early-onset familial Alzheimer's disease (FAD) in an Argentine pedigree of South American indian ethnic background. Pedigree spans 5 generations comprising more than 110 biological relatives. Clinical data supported the diagnosis of early onset FAD (mean age at onset 38.9 years) in 10 family members, including 3 with pathological confirmation (mean age at death 48.5). The pattern of transmission suggested autosomal dominant inheritance. Prominent features were mood changes, early language impairment, myoclonus, seizures and cerebellar signs. SPET displayed bilateral frontal, temporo-parietal and cerebellar hypoperfusion in early stages and in an asymptomatic member at risk, suggesting that SPET may have predictive value in this family. Immunohistochemistry showed β amyloid deposits within neuritic plaques and vessel walls and no anti-PrP immunoreactivity. DNA analysis showed no abnormalities in the β amyloid precursor protein gene. The identification of additional genetic defects in well characterized independent FAD pedigrees will contribute to the understanding of the pathogenesis of Alzheimer's disease. 相似文献
34.
Anya Pimentel Gomes Fernandes Vieira Jose Maria Sampaio Meneses Jr Renato Luiz Maia 《Journal of oral pathology & medicine》2007,36(2):117-119
Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details. 相似文献
35.
Gy?rgy Lang Attila Cseke? Georgios Stamatis Ludwig Lampl Leif Hagman Gabriel Mihai Marta Michael Rolf Mueller Walter Klepetko 《European journal of cardio-thoracic surgery》2004,25(2):160-166
OBJECTIVES: Persisting air leakage after pulmonary resection remains a significant problem. The aim of the study was to evaluate the incidence of air leakage after standard lobectomy and test the efficacy and safety of TachoComb (TC). METHODS: A total of 189 patients undergoing lobectomy were enrolled in a multi-centre, open, randomised, and prospective study to test the efficacy and safety of TachoComb (TC) for air leakage treatment. Air leakage was assessed by water submersion test, and scored as grades 0 if no, 1 if countable, 2 if a stream of and 3 if coalescent bubbles have been observed. Any sites with grade 3 air leakage received further stapling or limited suturing until grade 0, 1 or 2 was obtained. Treatment of air leakage was done with TC or suturing according to randomisation. Air leakage was assessed by further submersion tests. Postoperative air leakage was assessed using the Pleur-Evac system. RESULTS: Overall incidence of air leakage 48+/-6 h after surgery was 34% for TC and 37% for standard treatment (P=0.76). The reduction of intra-operative air leak intensity in the subgroup with grades 1-2 was significantly higher for the TC group (P=0.015). Postoperative air leakage intensity in the subgroup with air leakage grades 1-2 was lower for TC than standard treatment (P=0.047). The mean duration of postoperative air leakage in the subgroup with grades 1-2 was shorter for the TC group than for standard treatment, i.e. 1.9+/-1.4 vs. 2.7+/-2.2 days (P=0.015). CONCLUSIONS: TC could be proven as well-tolerated and safe. In the subgroup of patients with established air leakage, TC showed superior potential in reduction of intra-operative air leakage as well as in reduction of intensity and duration of postoperative air leakage. 相似文献
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37.
Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献
38.
Susi Elaine Dal''Belo Lorena Rigo Gaspar Patrícia Maria Berardo Gonçalves Maia Campos 《Skin research and technology》2006,12(4):241-246
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin. 相似文献
39.
Carla Santos Araújo Roberto Roncon Albuquerque Mónica Moreira Rodrigues Benedita Sampaio Maia Adelino F Leite Moreira Manuel Pestana 《Revista portuguesa de cardiologia》2006,25(4):419-427
INTRODUCTION: The biological activity of the natriuretic peptide (NP) system is dependent on the balance between NP tissue levels and the local expression of their receptors. In the kidney, the natriuretic peptide receptor type A (NPR-A) is the principal receptor mediating NP activity and is mainly expressed in the renal medulla. An increase in circulating NP levels is well documented in chronic renal failure (CRF); however, the renal expression of NPR-A has not been evaluated in this condition. METHODS: Wistar-Han rats were submitted to right nephrectomy plus ablation of both poles of the left kidney (3/4nx; n=27) or were sham operated (Sham; n=22) and followed for up to 26 weeks post surgery. Blood pressure measurements were performed weekly. Two, 10 and 26 weeks after surgery, renal sodium and creatinine excretion were evaluated and the kidneys removed for NPR-A mRNA quantification by real-time PCR. The results of mRNA quantification are expressed in arbitrary units (AU) set as the mean value of the Sham group (Sham=1 AU), after normalization for GAPDH (p<0.05). weeks after surgery) and in elevated fractional sodium excretion (+270%, 26 weeks after surgery). Although sodium intake was similar in 3/4nx and Sham rats, blood pressure was higher in 3/4nx rats and increased progressively throughout the study. This was accompanied by a marked decrease in NPR-A mRNA levels in the renal medulla from 3/4nx animals at 2, 10 and 26 weeks post surgery. Conclusion: In 3/4nx rats, the expression of NPR-A in the renal medulla of the remnant kidney is markedly reduced from 2 weeks up to 26 weeks post surgery. It is suggested that this may contribute to the progressive increase in blood pressure, as well as to the renal fibrosis observed in 3/4nx rats. 相似文献
40.
César Marques Salgado Claudio C Conti Paulo H B Becker 《Applied radiation and isotopes》2006,64(6):700-705
The Monte Carlo method was used to calculate the efficiency, escape and Compton curves of a planar high-purity germanium detector (HPGe) in the 20-150 keV energy. These curves were used for the determination of photons spectra produced by an X-ray machine in order to allow a precise characterization of photon beams applied to medical diagnosis. The detector was modeled with the MCNP5 computer code and validated by comparison with experimental data. The air kerma calculated after the spectra stripping was compared with ionization chamber measurements. 相似文献