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91.
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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Background: There are few data on echocardiographic indexes incorporating peak mitral inflow velocity (E), left atrial volume index (LAVi), and pulmonary artery pressure (PAP) for estimation of left ventricular (LV) filling pressure in patients with preserved LV ejection fraction (EF ≥ 50%). Methods: Patients underwent echocardiography ≤20 minutes of cardiac catheterization. Echocardiographic variables were compared to invasively measured LV end‐diastolic pressure (LVEDP). Results: Of the 122 patients, 67 (55%) were women, the mean age was 55 ± 9 years, the mean left ventricular ejection fraction (LVEF) was 61 ± 6%, 107 (88%) were hypertensive, and 79 (65%) had significant coronary artery disease at catheterization. E/Ea correlated with LVEDP (R = 0.68, P < 0.0001), compared to PAP (R = 0.53, P < 0.001), peak E velocity (R = 0.48, P < 0.001), and LAVi (R = 0.48, P < 0.001). E/Ea > 12 had 75% sensitivity and 78% specificity for LVEDP ≥ 20 mmHg (area under curve (AUC) = 0.79, P < 0.0001), compared with (PAP + LAVi)/2 > 30 (sensitivity = 72%, specificity = 80%, AUC = 0.84, P < 0.001) and (E + LAVi)/2 > 57 (sensitivity = 73% and specificity = 81%, AUC = 0.82, P < 0.001) (P = NS). E <60 cm/sec had 94% negative, and E>90 cm/sec had 96% positive, predictive value for LVEDP ≥ 20 mmHg. (E + LAVi)/2 added incrementally to E/Ea when E/Ea was in the gray zone. Conclusions: New, simple echocardiographic equations, (E + LAVi)/2 and (PAP + LAVi)/2, have comparable accuracy to E/Ea for LVEDP estimation in patients with cardiac disease and preserved LVEF, and (E + LAVi)/2 added incrementally to E/Ea alone when E/Ea was in the gray zone. Peak E velocity alone had high negative and positive predictive value for elevated LVEDP in this population. These simple echocardiographic variables could be used—in isolation or with E/Ea—in patients with cardiac disease and preserved LVEF for the diagnosis of diastolic heart failure. Echocardiography 2010;27:946‐953)  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   
97.
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   
98.

Aim

To report the results of surgery for obstructive right colon cancer (ORCC) and to identify risk factors associated with worse outcomes that may help surgeons to choose the best surgical option.

Methods

This is a retrospective national cohort study, including all patients operated on for ORCC from 2000 to 2015. Those treated with colonic stent or symptomatic treatment were excluded. We described outcomes after surgery for ORCC and performed multivariate analyses for mortality, morbidity and survival.

Results

Among 776 patients analyzed, 716 (92%) had their primary tumor removed, with primary anastomosis in 582 (82%). The remaining 194 underwent anastomosis with loop ileostomy (n = 21), resection with double-end stoma (n = 113), defunctioning stoma without resection (n = 48) and ileocolic by-pass (n = 12). Postoperative mortality, morbidity and anastomotic leak rates were 10%, 51% and 14%, respectively. In multivariate analysis, age >70, ASA score ≥3 and hemodynamic instability were predictors of postoperative mortality whereas ASA score ≥3, hemodynamic instability and intra-operative complications were predictors of severe morbidity. No factors were correlated with anastomotic leak. After a median follow-up of 26 months, 8% of patients were alive with a permanent stoma. Five-year overall, disease-free and cancer-specific survival was 42%, 42% and 62%, respectively. In multivariate analysis, peritonitis, synchronous metastases and absence of adjuvant chemotherapy were predictors of decreased overall survival.

Conclusions

Emergency surgery for ORCC is associated with high mortality and morbidity. Two third of patients with ORCC can be managed with resection and primary anastomosis. For high-risk patients, a staged surgical management may be discussed.  相似文献   
99.
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   
100.
CD4(+)CD25(+) regulatory T (Treg) cells suppress naive T cell responses, prevent autoimmunity, and delay allograft rejection. It is not known, however, whether Treg cells suppress allograft rejection mediated by memory T cells, as the latter mount faster and stronger immune responses than their naive counterparts. Here we show that antigen-induced, but not naive, Treg cells suppress allograft rejection mediated by memory CD8(+) T cells. Suppression was allospecific, as Treg cells induced by third-party antigens did not delay allograft rejection. In vivo and in vitro analyses revealed that the apoptosis of allospecific memory CD8(+) T cells is significantly increased in the presence of antigen-induced Treg cells, while their proliferation remains unaffected. Importantly, neither suppression of allograft rejection nor enhanced apoptosis of memory CD8(+) T cells was observed when Treg cells lacked CD30 or when CD30 ligand-CD30 interaction was blocked with anti-CD30 ligand Ab. This study therefore provides direct evidence that pathogenic memory T cells are amenable to suppression in an antigen-specific manner and identifies CD30 as a molecule that is critical for the regulation of memory T cell responses.  相似文献   
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