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71.
The development of body mass index (BMI) was measured during the first 6 months of life in three groups of infants [human immunodeficiency virus (HIV) -uninfected, n = 92; later symptomatic HIV-infected, n = 18; early symptomatic HIV-infected, n = 9] born to HIV-positive mothers and compared with a reference group (n = 65) born to healthy mothers. A trend towards lower values in the two groups of HIV-infected infants was already evident at birth. Among the four groups, HIV-uninfected infants showed the highest BMI values while the early-infected infants showed the lowest BMI values at all measurements. The later-infected group had a value close to the reference at 1 month, and then increased at slower rates than the uninfected and the reference groups. Infants born to HIV-positive mothers may have higher energy and nutrient requirements after birth, either to sustain an increased BMI development (when uninfected) or to meet catabolic mechanisms (when infected).  相似文献   
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Introduction

Selective conservatism for thoracic trauma is well established but the emergence of new technologies may cause management strategies to continue to evolve.

Methods

A retrospective study was conducted on thoracic trauma patients managed in a single institution in South Africa over a 4-year period to determine the appropriateness of our current policy of selective conservatism.

Results

A total of 1,239 patients were included in the study; 112 required an emergency thoracotomy, 125 were admitted for observation and 1,002 required a tube thoracostomy (TT). Ninety-one per cent of the patients were male and the median age was 24 years. Seventy-five per cent of the cases were penetrating trauma and the remaining were blunt trauma. The indications for TT were pneumothorax (PTX) (n=382, 38%), haemothorax (HTX) (n=300, 30%) and haemopneumothorax (HPTX) (n=320, 32%).A total of 13% (127/1,002) of all chest x-rays (CXR) following tube removal demonstrated residual pathologies that precluded immediate discharge: 32 (8%) in Group A (PTX), 44 (15%) in Group B (HTX) and 51 (16%) in Group C (HPTX). All 32 patients in Group A were simply observed and did not require further intervention. In Group B, 17 patients required repeat TTs and 27 required video assisted thoracoscopic surgery (VATS) for clearance of residual HTX. Twenty-nine patients in Group C required repeat TTs and twenty-two required VATS.

Conclusions

The vast majority of patients with thoracic trauma can be managed conservatively with TT alone. Residual pathology appeared to be lowest in patients with a PTX, which seldom requires treatment, while only a minority of patients required repeat TTs or VATS for a retained HTX. Selective conservatism is still appropriate in the current era in a developing world setting.  相似文献   
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AIM: To evaluate the techniques, results, and complications related to computed tomography(CT)-guided percutaneous core needle biopsies of solid pancreatic lesions.METHODS: CT-guided percutaneous biopsies of solid pancreatic lesions performed at a cancer reference center between January 2012 and September 2013 were retrospectively analyzed. Biopsy material was collected with a 16-20 G Tru-Core needle(10-15 cm; Angiotech, Vancouver, CA) using a coaxial system and automatic biopsy gun. When direct access to the lesion was not possible, indirect(transgastric or transhepatic) access or hydrodissection and/or pneumodissection maneuvers were used. Characteristics of the patients, lesions, procedures, and histologic results were recorded using a standardized form. RESULTS: A total of 103 procedures included in the study were performed on patients with a mean age of 64.8 year(range: 39-94 year). The mean size of the pancreatic lesions was 45.5 mm(range: 15-195 mm). Most(75/103, 72.8%) procedures were performed via direct access, though hydrodissection and/or pneumodissection were used in 22.2%(23/103) of cases and indirect transhepatic or transgastric access was used in 4.8%(5/103) of cases. Histologic analysis was performed on all biopsies, and diagnoses were conclusive in 98.1%(101/103) of cases, confirming3.9%(4/103) of tumors were benign and 94.2%(97/103) were malignant; results were atypical in 1.9%(2/103) of cases, requiring a repeat biopsy to diagnose a neuroendocrine tumor, and surgical resection to confirm a primary adenocarcinoma. Only mild/moderate complications were observed in 9/103 patients(8.7%),and they were more commonly associated with biopsies of lesions located in the head/uncinate process(n =8), than of those located in the body/tail(n = 1) of the pancreas, but this difference was not significant.CONCLUSION: CT-guided biopsy of a pancreatic lesion is a safe procedure with a high success rate, and is an excellent option for minimally invasive diagnosis.  相似文献   
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Granulomatosis with polyangiitis (GPA) is a potentially lethal disease characterized by systemic necrotizing vasculitis, which affects small‐ and medium‐sized blood vessels and is often associated with serum cytoplasmic antineutrophil cytoplasmic antibody. The upper and lower respiratory tract and kidney are the most involved sites, but oral lesions can be identified in 6–13% of the cases, whereas in only 2% of the cases, oral manifestations represent the first signal of the disease usually as gingival swellings or unspecific ulcerations. Without treatment, the mainstay of which is the combination of immunosuppressants and systemic corticosteroids, GPA may run a fatal course. In this report we describe an original case of GPA affecting a 75‐year‐old female patient referred to our service due to a gingival swelling with 3‐month duration. Although the patient was correctly diagnosed and promptly treated, she died 3 months after the initial diagnosis.  相似文献   
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Bone marrow origin of a B-cell lymphoma   总被引:3,自引:0,他引:3  
To search for precursors of the neoplastic B cells in a patient with a nodular lymphoma, we produced a monoclonal antibody to a variable region idiotope on the lymphoma IgM heavy chain. Clonal ancestors of the lymphoma cells were identified by this marker among bone marrow pre- B cells (5% to 26%). A second antiidiotype (anti-Id) antibody specific for the complete lymphoma IgM kappa recognized 10% of B cells in bone marrow and blood and greater than 95% of B cells in lymphomatous lymph nodes, including one obtained after tumor conversion to a diffuse large cell lymphoma. Immunoglobulin gene analysis surprisingly revealed expansion of multiple clones of early B lineage cells in bone marrow, including members of the neoplastic clone. The data suggest that this lymphoma arose through a progression of transformational events beginning in bone marrow: first, creation of an oligoclonal pre- neoplastic pool of pre-B cells, subsequent conversion of a single subclone into low grade neoplastic B cells that homed to the lymph node follicles, and later progression to a more invasive form of the B-cell lymphoma.  相似文献   
77.
Accumulation of toxic amyloid-beta (Abeta)-peptide is suggested to cause oxidative stress in Alzheimer's disease (AD) brain, and decrease the content of polyunsaturated fatty acids (PUFA) in neuronal membrane lipids. The senescence accelerated prone mice (SAMP8) have age-related increases in the level of hippocampal Abeta-peptide, learning and memory deficits, and a shorter lifespan than their controls. The effects of age-related oxidative damage on PUFA content in membrane phospholipids (PL), and alpha-tocopherol concentration were investigated in hippocampus and amygdala of 2-, 4-, 12-, and 18-month-old SAMP8 mice. In comparison to the younger SAMP8 mice, the hippocampus of the 12-month-old mice contained lower proportions of docosahexaenoic acid (DHA) in phosphatidylserine (PS) and phosphatidylinositol (PI), and higher proportions of arachidonic acid (AA) in PS. Their amygdala contained a lower proportion of AA in phosphatidylcholine (PC). In the hippocampus of the oldest age group, the proportions of DHA in PS, and AA in PC and PI were higher than in the younger age groups. At 2 months of age, the amygdala contained a higher concentration of alpha-tocopherol than the hippocampus, but this difference between the two brain regions was lost with aging. The oldest age group contained the highest concentration of alpha-tocopherol, indicating a protection against oxidative damage of PUFA in brain membrane phospholipids.  相似文献   
78.
OBJECTIVE: To investigate whether there is a relationship between maternal intake of cod-liver oil in early and late pregnancy and hypertensive disorders in pregnancy. DESIGN: An observational prospective study. SETTING: Free-living conditions in a community with traditional fish and cod-liver oil consumption. POPULATION: Four hundred and eighty-eight low-risk pregnant Icelandic women. METHODS: Maternal use of cod-liver oil, foods and other supplements was estimated with a semiquantitative food frequency questionnaire covering food intake together with lifestyle factors for the previous 3 months. Questionnaires were filled out twice, between 11 and 15 weeks of gestation and between 34 and 37 weeks of gestation. Supplements related to hypertensive disorders in pregnancy, i.e. gestational hypertension and pre-eclampsia, were presented, with logistic regression controlling for potential confounding. MAIN OUTCOME MEASURES: Gestational hypertension, pre-eclampsia, cod-liver oil and multivitamins. RESULTS: The odds ratio for developing hypertensive disorders in pregnancy for women consuming liquid cod-liver oil was 4.7 (95% CI 1.8-12.6, P= 0.002), after adjusting for confounding factors. By dividing the amount of n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) into centiles, the odds ratio for hypertensive disorders across groups for n-3 LCPUFA suggested a u-shaped curve (P = 0.008). Similar results were found for gestational hypertension alone. Further, the use of multivitamin supplements without vitamins A and D in late pregnancy doubled the odds of hypertensive disorders (OR 2.4, 95% CI 1.0-5.4, P= 0.044). CONCLUSIONS: Consumption of high doses of n-3 LCPUFA in early pregnancy, or other nutrients found in liquid cod-liver oil, may increase the risk of developing hypertensive disorders in pregnancy.  相似文献   
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