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1.
Circannual variation in lymphocyte subsets, revisited   总被引:2,自引:0,他引:2  
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply.  相似文献   
2.
The family history in family practice: a questionnaire study   总被引:9,自引:7,他引:2  
Summerton  N; Garrood  PV 《Family practice》1997,14(4):285-288
OBJECTIVES: Our aims were to investigate family medical history taking in general practice, and to evaluate the value attached to the family medical history as an aid to decision making in general practice. METHOD: A postal questionnaire survey was conducted among all 291 GPs working within the Calderdale and Kirklees Health Authority area. Each questionnaire was followed by a reminder. The main outcome measures were answers to questions on routine and opportunistic family history taking and a question about transmitting knowledge about genetic risk to other members of the family. Questions were also posed about the value attached to the family medical history as an aid to decision making. RESULTS: A total of 193 GPs returned the questionnaire (response rate 66.3%). On registration, 94.3% of GPs indicated that enquiries were made about a family history of coronary heart disease. Breast and colorectal cancer were specifically asked about by 48.4% and 30.7% of GPs, respectively. One-fifth of respondents indicated that they asked a general question about family medical history. A little over one-quarter of respondents indicated that they made opportunistic enquiries about the family history or suggested that the patient should inform other members of the family about possible risks. In the scenarios highlighted in this study, the majority of respondents felt that the family medical history had value as an aid to decision making. This was particularly the case for checking a patient's cholesterol (92.1%) and for initiating referrals in younger patients with possible cancer-related symptoms (three-quarters of respondents). CONCLUSION: GPs value the family medical history as an aid to decision making. Unfortunately, apart from enquiries about coronary heart disease, routine or opportunistic family history taking is not occurring in practice. Mechanisms need to be sought to extract information from the family medical history so that it can be more effectively used by GPs.   相似文献   
3.
Anemia is estimated to affect half the school-age children and adolescents in developing countries. The main causes are parasitic infections, malaria, and low iron intake. This study aimed to describe the prevalence of anemia, parasitic infections, and nutritional status of children attending public primary schools in Aracaju, Northeast Brazil. Of 360 students, 26.7% were anemic, and prevalence was higher in children under 8 and over 15 years of age. Overall prevalence of intestinal parasites was 42%, with Ascaris lumbricoides (28.7%), Trichuris trichiura (15.6%), and hookworm (1. 7%) most frequently found. There was an association between parasitic infections and poor sanitary conditions, but there was no association between anemia and presence of intestinal parasites. Height-for-age Z scores were lower than the NCHS standard, and prevalence of stunting was 5.4%. Although intestinal parasites were not associated with anemia, children with parasites had lower nutritional indices (weight- and height-for-age Z scores) than those without parasites.  相似文献   
4.
Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live‐born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti‐T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti‐T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti‐T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty‐three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow‐up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.4–8.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted.  相似文献   
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J Oral Pathol Med (2012) 41 : 47–53 Objective: The aim of this study was to investigate the presence of CD1a‐positive Langerhans cells and their relationship with E‐cadherin in minor salivary gland tumors. Methods: Twenty‐seven minor salivary gland tumors were investigated using immunohistochemistry for CD1a and E‐cadherin. Results: A significant difference regarding the mean density of CD1a‐positive Langerhans cells was observed between pleomorphic adenomas and malignant tumors studied (P = 0.001). No CD1a‐positive cells were detected in most cases (n = 5) of cystic adenoid carcinomas. CD1a‐positive cells were detected in one mucoepidermoid carcinoma case, and six low‐grade polymorphous adenocarcinomas cases. Comparison of the mean density of CD1a‐positive cells between the three malignant tumors showed no significant difference (P = 0.127). No significant difference was observed in the presence of E‐cadherin between tumors (P = 0.73), but it was detected in 24 cases. Conclusions: The lack of CD1a‐positive in malignant salivary gland tumors facilitates the neoplastic development and suggests that these cells might be useful as auxiliary diagnostic and prognostic tool in minor salivary gland tumors. Furthermore, it is suggested that E‐cadherin mediates cell adhesion in these tumors although we did not demonstrate significance.  相似文献   
8.
This study was designed to describe the epidemiology and risk factors for nosocomial infection (NI) in a Brazilian neonatal intensive care unit (NICU). This study was a retrospective cohort from January to December, 2003. All neonates admitted to the NICU. Infection surveillance was conducted according to the NNIS, CDC. Chi-square test and logistic regression model were performed for statistical analyses. The study was conducted at a public, tertiary referral NICU of a teaching hospital in the Northeast of Brazil. A total of 948 medical records were reviewed. Overall NI incidence rate was 34%. The main neonatal NI was bloodstream infection (68.1%), with clinical sepsis accounting for 47.2%, and pneumonia was the second most common NI (8.6%). Multivariate analysis identified seven independent risk factors for NIs: birth weight, exposure to parenteral nutrition, percutaneous catheter, central venous catheter or mechanical ventilation, abruptio placentae and mother's sexually transmitted disease (STD). Neonates from mothers with STD or abruptio placentae, those weighing less than 1,500 g at birth or those who used invasive devices were at increased risk for acquiring NI.  相似文献   
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Autozygosity mapping is a powerful technique for the identification of rare, autosomal recessive, disease‐causing genes. The ease with which this category of disease gene can be identified has greatly increased through the availability of genome‐wide SNP genotyping microarrays and subsequently of exome sequencing. Although these methods have simplified the generation of experimental data, its analysis, particularly when disparate data types must be integrated, remains time consuming. Moreover, the huge volume of sequence variant data generated from next generation sequencing experiments opens up the possibility of using these data instead of microarray genotype data to identify disease loci. To allow these two types of data to be used in an integrated fashion, we have developed AgileVCFMapper, a program that performs both the mapping of disease loci by SNP genotyping and the analysis of potentially deleterious variants using exome sequence variant data, in a single step. This method does not require microarray SNP genotype data, although analysis with a combination of microarray and exome genotype data enables more precise delineation of disease loci, due to superior marker density and distribution.  相似文献   
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