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1.
Maya families from Guatemala migrated to the United States in record numbers from the late 1970s to the early 1990s. Births to Maya immigrant women have created a sizable number of Maya American children. The height and sitting height of 5 to 12 years children (n = 431) were measured in 1999 and 2000. Leg length was estimated and the sitting height ratio was calculated. These data were compared with a sample of Maya children living in Guatemala measured in 1998 (n = 1,347). Maya American children are currently 11.54 cm taller and 6.83 cm longer‐legged, on average, than Maya children living in Guatemala. Consequently, the Maya Americans have a significantly lower average sitting height ratio (i.e., relatively longer legs in proportion to length of the head and trunk) than do the Maya in Guatemala. These results add support to the hypothesis that both the height and body proportions of human populations are sensitive indicators of the quality of the environment for growth. Am. J. Hum. Biol. 14:753–761, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
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A retrospective study was performed to describe the features of the pollinosis caused by Betula in the area of Ourense, Spain. The pollen count was carried out with a Lanzoni volumetric Hirts spore trap (1993-2000). The Betula pollen represented 5% over the annual total (annual mean quantity: 965 grains). It was present in the air from March to mid-May. The highest peaks took place in April (maximum values mean: 131 grains/m3). The medical records of 222 patients (mean age 25.66 years) diagnosed with pollinosis (1998-2000), who lived at less than 30 km. from the spore trap, were reviewed. In all of them, the skin-prick test (SPT) was carried out with pollen allergens. The percentages of positive SPT were: Lolium perenne, 91.89% (16.6% monosensitized); Plantago lanceolata, 71.17% (1.26% monosensitized); Betula alba, 41.89% (10.75% monosensitized); Platanus hybrida, 34.95%; Olea europea, 10.36%; and Parietaria judaica, 6.3%. The mean age of Betula monosensitized patients was 44.7 years. The majority of them had symptoms in March-April, 40% had asthma symptoms, 80% had lived in Central Europe, and 30% of them presented an oral allergy syndrome to fruits. There were 41.93% of the patients with positive SPT to Betula pollen who had asthma symptoms, in comparison with 23.25% of the patients with negative SPT to Betula (p = 0.0034). There were 20.28% of the patients with positive SPT to Betula pollen, who had lived in Central Europe, in comparison with 4.27% of the patients with negative SPT to Betula, p: 0.00049. The relative risk of sensitization was 2.05. CONCLUSIONS: Betula pollen was the second cause of clinical pollinosis in our patients, after grass, being responsible of the symptoms in the early spring, in a small number of the patients in their forties. The presence of asthma was higher in Betula sensitized patients, and the residence in Central Europe was a sensitization risk factor.  相似文献   
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The modes of infection and transmission of Pneumocystis jiroveci remain unclear. This study explored the relationship between the incidence of infection and climatic factors. In total, 536 cases of P. jiroveci infection were identified in the period 1994-1998, with an inverse correlation between the incidence of Pneumocystis pneumonia and the minimum mean ambient temperature (Spearman correlation coefficient: r - 0.30; p 0.02; ARIMA model: r - 0.250, p 0.07). The highest number of cases occurred in winter (anova test, p < 0.05), and there was a clear season-related incidence of P. jiroveci infection.  相似文献   
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To elucidate whether any relationship exists between genetic polymorphic acetylation and the risk for multiple sclerosis (MS), we determined this polymorphism, using sulphamethazine, in 71 patients with definite MS and in 268 age-matched controls. Thirty-seven patients (52.1%) and 151 controls (56.3%) were classified as slow acetylators (not significant difference). No relation was found between acetylator polymorphism and age at onset of disease in MS patient's group. Our results do not support the existence of any relationship between acetylator polymorphism and the risk for MS.  相似文献   
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BACKGROUND AND OBJECTIVE: We present the case of a female patient 29 years of age with antecedents of laparoscopic laser ablation for endometriosis, laparoscopic appendectomy, and umbilical hernioplasty. METHODS: The patient was admitted to the hospital's emergency room for abdominal pain in the epigastrium, transfixing, irradiating to both upper quadrants and to the lumbar region, accompanied by nausea and gastrobiliary vomiting. Lipase determination was 170 mg/dL. Other laboratory findings were normal. Plain abdominal films on the patient's admission were normal, and computed tomography (CT) showed data compatible with acute pancreatitis. Without improvement during the patient's hospital stay, pain and vomiting increased in intensity and frequency. RESULTS: New abdominal x-rays revealed dilatation of small bowel loops. Management was begun for intestinal obstruction, with intravenous hydration and placement of a nasogastric tube without a good response. At 48 hours, a diagnostic laparoscopy was performed, revealing a 3-cm internal hernia in the left broad ligament in which a 20-cm segment of terminal ileum was encased. We performed liberation of the ileal segment and closed the hernial orifice by using the laparoscopic approach. CONCLUSION: The patient's evolution was excellent.  相似文献   
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Calcium channel blockers can act on dopaminergic systems, and some reports suggest that they could be useful for the treatment of several movement disorders. In order to assess the efficacy of nicardipine in tics disorders we performed a prospective open non-controlled study which included 10 previously untreated patients. Our results suggest that nicardipine could be a useful and safe treatment for tics.  相似文献   
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The powerful genetic polymorphism of the HLA system has been used to identify individuals and populations. Ethnic groups may be characterized by specific HLA allele frequencies and particular extended HLA haplotypes; also, genetic relationships among these groups may be deduced. In the present study, serology and DNA typing were used to detect HLA-A, -B, -C, -DR, and -DQ alleles in each individual and to calculae characteristic haplotypes in Algerians. These results were compared to those previously obtained in other populations, particularly northern Mediterraneans; genetic distances and their respective dendrograms place Basques and Spaniards closer to Algerians than to other Europeans. Also, characteristic Basque and/or Spanish haplotypes are found in Algerians; i.e., A30-B18-Cw3-DR3-DQ2 and Al-B57-Ctv7-DR7-DQ2. This supports the evidence that the Algerian population, mainly its paleo-North African component (Berbers), has a common descent with Basques and Spaniards, probably reflecting a preneolithic relationship between Iberians and paleo-North Africans.  相似文献   
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