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41.
ABSTRACT: BACKGROUND: Caesarean section rates in Brazil have been steadily increasing. In 2009, for the first time, the number of children born by this type of procedure was greater than the number of vaginal births. Caesarean section is associated with a series of adverse effects on the women and newborn, and recent evidence suggests that the increasing rates of prematurity and low birth weight in Brazil are associated to the increasing rates of Caesarean section and labour induction. METHODS: Nationwide hospital-based cohort study of postnatal women and their offspring with follow-up at 45 to 60 days after birth. The sample was stratified by geographic macro-region, type of the municipality and by type of hospital governance. The number of postnatal women sampled was 23,940, distributed in 191 municipalities throughout Brazil. Two electronic questionnaires were applied to the postnatal women, one baseline face-to-face and one follow-up telephone interview. Two other questionnaires were filled with information on patients[RIGHT SINGLE QUOTATION MARK] medical records and to assess hospital facilities. The primary outcome was the percentage of Caesarean sections (total, elective and according to Robson[RIGHT SINGLE QUOTATION MARK]s groups). Secondary outcomes were: post-partum pain; breastfeeding initiation; severe/near miss maternal morbidity; reasons for maternal mortality; prematurity; low birth weight; use of oxygen use after birth and mechanical ventilation; admission to neonatal ICU; stillbirths; neonatal mortality; readmission in hospital; use of surfactant; asphyxia; severe/near miss neonatal morbidity. The association between variables were investigated using bivariate, stratified and multivariate model analyses. Statistical tests were applied according to data distribution and homogeneity of variances of groups to be compared. All analyses were taken into consideration for the complex sample design. DISCUSSION: This study, for the first time, depicts a national panorama of labour and birth outcomes in Brazil. Regardless of the socioeconomic level, demand for Caesarean section appears to be based on the belief that the quality of obstetric care is closely associated to the technology used in labour and birth. Within this context, it was justified to conduct a nationwide study to understand the reasons that lead pregnant women to submit to Caesarean sections and to verify any association between this type of birth and it's consequences on postnatal health.  相似文献   
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The t(2;5)(p23;q35) translocation associated with CD30-positive anaplastic large cell lymphoma results in the production of a NPM-ALK chimeric protein, consisting of the N-terminal portion of the NPM protein joined to the entire cytoplasmic domain of the neural receptor tyrosine kinase ALK. The ALK gene products were identified in paraffin sections by using a new anti-ALK (cytoplasmic portion) monoclonal antibody (ALKc) that tends to react more strongly than a previously described ALK1 antibody with the nuclei of ALK-expressing tumor cells after microwave heating in 1 mmol/L ethylenediaminetetraacetic acid buffer, pH 8.0. The ALKc monoclonal antibody reacted selectively with 60% of anaplastic large cell lymphoma cases (60 of 100), which occurred mainly in the first three decades of life and consistently displayed a T/null phenotype. This group of ALK-positive tumors showed a wide morphological spectrum including cases with features of anaplastic large cell lymphoma “common” type (75%), “lymphohistiocytic” (10%), “small cell” (8.3%), “giant cell” (3.3%), and “Hodgkin’s like” (3.3%). CD30-positive large anaplastic cells expressing the ALK protein both in the cytoplasm and nucleus represented the dominant tumor population in the common, Hodgkin’s-like and giant cell types, but they were present at a smaller percentage (often with a perivascular distribution) also in cases with lymphohistiocytic and small cell features. In this study, the ALKc antibody also allowed us to identify small neoplastic cells (usually CD30 negative) with nucleus-restricted ALK positivity that were, by definition, more evident in the small cell variant but were also found in cases with lymphohistiocytic, common, and “Hodgkin’s-like” features. These findings, which have not been previously emphasized, strongly suggest that the neoplastic lesion (the NPM-ALK gene) must be present both in the large anaplastic and small tumor cells, and that ALK-positive lymphomas lie on a spectrum, their position being defined by the ratio of small to large neoplastic cells. Notably, about 15% of all ALK-positive lymphomas (usually of the common or giant cell variant) showed a cytoplasm-restricted ALK positivity, which suggests that the ALK gene may have fused with a partner(s) other than NPM. From a diagnostic point of view, detection of the ALK protein was useful in distinguishing anaplastic large cell lymphoma cases of lymphohistiocytic and small cell variants from reactive conditions and other peripheral T-cell lymphoma subtypes, as well as for detecting a small number of tumor cells in lymphohemopoietic tissues. In conclusion, ALK positivity appears to define a clinicopathological entity with a T/null phenotype (“ALK lymphomas”), but one that shows a wider spectrum of morphological patterns than has been appreciated in the past.  相似文献   
43.
OBJECTIVE: To evaluate the effect of a gluten-free diet on growth and adult height, when available, in coeliac children without gastrointestinal symptoms. PATIENTS AND METHODS: Sixty-one coeliac children without gastro-intestinal symptoms were included in the study. The age at diagnosis was 9.50 +/- 3.3 years. Thirty-eight had short stature at diagnosis (< 10th percentile) and 23 had normal stature. Thirty-seven reached adult height. RESULTS: After beginning the diet an increase in growth velocity was seen in 30 patients (responders) (20 with initial short stature), while in 31 patients (18 with short stature) there was no catch-up growth (non-responders). Bone age at diagnosis was significantly more delayed in the responders than in the non-responders. Target height was significantly higher in children with normal stature at diagnosis than those with short stature. Growth hormone (GH) deficiency was found and confirmed after 6-12 months of diet in 12 of the 38 patients (32%) with short stature. In the group of the 30 'short' patients who attained final height, target height was attained or improved in 12 patients (40%): in eight of the 16 (50%) responders and in four of the 14 (29%) non-responders; in eight (all responders) out of 22 (36%) without GH deficiency, and in four out of eight (50%) patients with GH deficiency treated with GH (all non-responders). CONCLUSIONS: In children in whom coeliac disease is diagnosed because of short stature, a gluten-free diet will be successful if at diagnosis there is a delay of bone age and in the first year of diet there is an evident catch-up growth. When this does not occur, i.e. in half of the patients (18 out of 38), it may be because of an associated and transient GH deficiency. In these patients a period of GH replacement therapy as well as a gluten-free diet may improve their final height.  相似文献   
44.
OBJECTIVE: To compare the development of motor function in children born preterm with those born at term, at 8 and 12 months of age. To investigate the relation of motor function quality at the age of 8 months with motor ability at 12 months. METHOD: Thirty-two children participated in this study: 16 were born preterm (risk group) and 16 were born at term (control group). The spontaneous movements of the children were assessed at 8 months and their mobility skills and independence were assessed at 12 months (corrected ages for the preterm group), using standardized developmental tests (AIMS and PEDI, respectively). Data were analysed using independent t-tests (between-group comparison) and Pearson correlation coefficients (within-group comparison). RESULTS: There was no significant difference in motor function, between those born preterm with those born at term, either at 8 or at 12 months of age. In the control group, there was significant association (r=0.67; p=0.004) between movement at 8 months and mobility skills at 12 months. In the risk group, there was significant relationship between skills and independence in mobility, at 12 months corrected age (r=0.80; p=0.0001). CONCLUSION: Preterm born children, without other disorders and with age correction, might show a similar motor development as those born at term. The path for the acquisition of motor abilities in preterm born children appears to differ among those infants.  相似文献   
45.
This study was based on a prospective and a retrospective analysis of 35 patients who met Bohan and Peter criteria for juvenile dermatomyositis diagnosis.The mean follow-up time was three years ten months. Calcinosis was present in five (14.28 %) patients, cutaneous ulcers in four (11.42%), and systemic involvement in nine (27.71%) patients. All patients presented alterations in the serum levels of muscle enzymes, and all of them were submitted to muscle biopsy as a diagnostic procedure. Nine (25.71%) patients received corticotherapy prior to and 26 (74.28%) after the muscle biopsy. Chloroquine, methotrexate, cyclosporine, cyclophosphamide and intravenous immunoglobulin were used in patients with poor response to corticotherapy. Continuation of cutaneous manifestations was observed in 4 (11.43%) patients, laboratorial activity in 1 (2.85%), cutaneous and laboratorial activities in 3 (8.57%). Ten (28.57%) patients were out of activity, and 17 (48.57%) in remission at study end-point, on March 2002. Two (5.71%) patients died.  相似文献   
46.
Between 1968 and 1975, 44 evaluable children under 16 years of age with the histologic diagnosis of non-Hodgkin malignant lymphoma (ML) were treated at the Istituto Nazionale Tumori of Milan. Histologic diagnoses were reclassified as follows: 13 lymphoblastic (others) ML, 15 convoluted cell type lymphoblastic ML, 9 Burkitt type ML, and 7 immunoblastic ML. Only 36% of the patients had stage I and II disease. At diagnosis 25% showed malignant cells in the bone marrow smears. Bone marrow infiltration was particularly frequent in the convoluted cell type lymphoblastic ML and in the lymphoblastic (others) ML subgroups. Burkitt type ML frequently was associated with abdominal lesions and subsequently a high incidence of central nervous system involvement. Patients with stage I and II ML were encountered mostly in the immunoblastic ML subgroup. After 1973 more intensive chemotherapy plus radiotherapy seems to have slightly improved the survival of the patients, except in the Burkitt type ML subgroup.  相似文献   
47.
Hepatocellular transplant may potentially be efficacious for the treatment of selected liver metabolic disorders and acute hepatic failure. On the other hand, the use of hepatocyte cold preservation techniques in these transplantation protocols would allow to have available cells at the right time and place and, consequently, make an optimal use of scarce human hepatocytes. In our experiments we evaluated the biodistribution and functionality of cold preserved hepatocytes transplanted in the spleen of syngeneic rats. Isolated hepatocytes were labeled with the fluorescent dye 5(6)-carboxyfluorescein diacetate succinimidyl-ester, cold-preserved in modified University of Wisconsin (UW) solution for 48 or 96 h, and then transplanted into the spleen. Recipient animals were euthanized at 0 and 3 h, and at 1, 2, 3, 5, 10, and 14 days after transplantation for tissue analysis. Labeled hepatocytes were clearly identifiable in the recipient tissues up to 14 days later. Fluorescence microscopy also showed no significant differences in biodistribution when either cold stored or freshly isolated hepatocytes were transplanted. In addition, functional activity of transplanted cells was demonstrated by immunohistochemical detection of albumin at levels comparable to those found in normal hepatocytes. Our findings establish that cold preserved hepatocytes appear morphologically and biochemically normal after intrasplenic transplantation. Consequently, it indicates that modified UW solution makes it possible to safety preserve hepatocytes for up to 96 h before transplantation, perhaps providing sufficient time for hepatocyte allocation and potential recipient preparation, if applicable clinically.  相似文献   
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We report a case of complex traumatic hand fracture successfully treated with low-intensity ultrasound in an elite soccer goalkeeper. A single 20-min daily application of low-intensity pulsed ultrasound (frequency, 1.5 Mhz; intensity, 30 mW/cm2) provided by Exogen's Sonic Accelerated Fracture Healing System was administered for 24 days on end. Plain radiographs, ultrasonography, and computed tomographic scans were performed to diagnose and to follow-up the evolution of the fracture during the treatment. After 24 days, the athlete was allowed to recommence his specific sport activity with a modified soccer glove and functional taping. After 2 months, radiographs demonstrated the complete healing, with no displacement, of the fracture sites.  相似文献   
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