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51.
A prospective study was undertaken to identify possible factors related to the duration of breast feeding. Two hundred and thirty-eight mothers who had delivered normal single babies with birth weights greater than 2.5 kg and had initiated breast feeding were randomly selected at the maternity hospital, Hospital de Clinicas de Porto Alegre, Brazil, and followed by mail questionnaires until termination of breast feeding, or until the end of the first year. If no reply was received, telephone contact or home visits were made. The group of mothers who stopped breast feeding prior to the end of the third month was compared with those who extended breast feeding beyond three months with respect to socioeconomic, biological, environmental, medical and psychological factors. The variables with a significant coefficient of association with early termination of breast feeding were maternal education, past experience with breast feeding, help of a maid, help with housework provided by a relative, breast feeding orientation during prenatal care and encouragement from the husband. These factors act simultaneously, with interactions among them.  相似文献   
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A patient with nasopharyngeal carcinoma developed clubbing and hypertrophic osteoarthropathy 6 months before radiological detection of secondary deposits in the lung. Another patient with nasopharyngeal carcinoma developed digital clubbing and hypertrophic osteoarthropathy 6 months after the discovery of lung metastases. Development of a paraneoplastic syndrome in the form of hypertrophic osteoarthropathy and digital clubbing is very rare. This manifestation of nasopharyngeal cancers is presented, with a short review of its biology and pathogenesis.  相似文献   
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This study was conducted to analyse the effect of childhood-onset diabetes mellitus on adult height. The height at time of diagnosis of 35 children with insulin-dependent diabetes mellitus (IDDM) was compared with growth reference data. Predictions of the adult height were made at the time of diagnosis using the target height and the Tanner-Whitehouse II method. The adult height was compared with both the predicted values and the height of healthy adults. The height at time of diagnosis of the prepubertal children was increased compared with growth reference data, in contrast to pubertal children who had normal heights. Only the prepubertal boys were taller at time of diagnosis. The adult height of the prepubertal patients was taller than growth reference data. The mean adult height in all patients did not differ significantly from the predicted heights. In conclusion, the increased height at the start of IDDM in prepubertal children persists until adulthood.  相似文献   
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Elevated homocysteine (Hcy) levels are observed in two apparently unrelated diseases: neural-tube defects (NTD) and premature vascular disease. Defective human methionine synthase (MS) could result in elevated Hcy levels. We sequenced the coding region of MS in 8 hyperhomocysteinaemic patients (4 NTD patients and 4 patients with pregnancies complicated by spiral arterial disease, SAD). We identified only one mutation resulting in an amino acid substitution: an A-->G transition at bp 2756, converting an aspartic acid (D919) into a glycine (G). We screened genomic DNA for the presence of this mutation in 56 NTD patients, 69 mothers of children with NTD, 108 SAD patients and 364 controls. There was no increased prevalence of the GG and AG genotypes in NTD patients, their mothers or SAD patients. The D919G mutation does not seem to be a risk factor for NTD or vascular disease. We then examined the mean Hcy levels for each MS genotype. There was no correlation between GG- or AG-genotype and Hcy levels. The D919G mutation is thus a fairly prevalent, and probably benign polymorphism. This study, though limited, provides no evidence for a major involvement of MS in the aetiology of homocysteine-related diseases such as NTD or vascular disease.   相似文献   
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The mouse Pim-1 gene encodes two cytoplasmic serine-threonine-specific protein kinases. The gene has been found to be activated (overexpressed) by retroviral insertion in hematopoietic tumors in mice. Transgenic mice that overexpress Pim-1 (E mu-Pim-1) have a low incidence of spontaneous T-cell lymphomas and an increased susceptibility to Moloney murine leukemia virus and N-ethyl-N- nitrosourea-induced lymphomas. Apart from a slight enlargement of the spleen, no abnormalities were found in prelymphomatous transgenic mice. Inactivation of the Pim-1 gene in the germline of mice resulted in mice with a surprisingly subtle phenotype. Therefore, we investigated whether subtle effects of the absence of Pim-1 could be made visible during in vitro culturing of hematopoietic cells. We found that bone marrow-derived mast cells (BMMC) lacking Pim-1 had a distinct growth disadvantage when grown on interleukin (IL)-3, but not when stimulated by the factors IL-4, IL-9, or Steel factor (SF). This indicates a role for Pim-1 as a modulator of the IL-3 signal transduction pathway.  相似文献   
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After ABO‐incompatible kidney transplantation, postoperative plasma exchange (PE) or immunoadsorption (IA) is performed per protocol or depending on postoperative A/B‐titers to prevent acute rejection. However, the need for postoperative PE or IA is not known. Since 2006, 30 consecutive patients received three standard postoperative IAs. Starting from 2009, the last 46 patients received only preoperative IA. Preoperative desensitization consisted of rituximab, tacrolimus, mycophenolate mofetil, prednisone and intravenous immunoglobulins. Antigen‐specific IA was performed pre‐operatively with the Glycosorb device. Biopsy‐proven acute rejections either antibody‐mediated (AMR) or mixed cellular and antibody‐mediated (MAR) within 3 months were recorded. The postoperative titer in patients with postoperative IA did not exceed 1:16 (IgG 1:4 [<2–16] median and range). The postoperative IgG titer was not significantly different after abandoning postoperative IA, although three patients had titers of 1:32 and one patient even 1:128. Rejections tended to be more frequent in the group with postoperative IA: 6 AMR and 3 MAR were recorded in 30 patients, vs. 4 AMR and 1 MAR in the 46 patients without postoperative IA (30 vs. 11%, P = 0.067). Baseline characteristics differed however: in the group with postoperative IA the vast majority had blood group O (87 vs. 52%, P = 0.003). Also, the IgG titer on the day of transplantation was higher (1:4 [<2–16] vs. 1:2 [<2–32], P = 0.007). All 14 patients with AMR and MAR rejections had postoperative IgG titers ≤1:16. Postoperative removal of A/B‐antibodies can be safely removed from the ABOi transplantation protocol using strict preoperative criteria for antibody lowering.  相似文献   
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