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排序方式: 共有546条查询结果,搜索用时 31 毫秒
31.
Wayland C 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2004,20(6):1757-1761
This paper presents a preliminary profile of infant feeding practices in a peri-urban Amazonian community. A random sample of 180 households with at least one child under the age of five years were interviewed in 1996 as part of a maternal-child health survey conducted in a peri-urban neighborhood in Rio Branco, Acre, Brazil. Since some households had more than one child under the age of five, data were collected for a total of 250 children. The results of the survey indicate that initiation of breastfeeding is nearly universal, with 96.0% of women breastfeeding their infants at birth. However, many mothers terminate breastfeeding before the recommended age. Forty-five percent of infants are weaned before six months and 62.0% are weaned before 12 months. The survey also reveals that mothers give supplemental food and drink at an early age. Finally, while women give a variety of responses for why breastfeeding was terminated, the most common answer (42.0%) was that the infant refused the breast. The meaning and implications of this response merit further investigation. 相似文献
32.
McBurney PG Hanevold CD Hernandez CM Waller JL McKie KM 《Journal of pediatric hematology/oncology》2002,24(6):473-477
PURPOSE: To determine the prevalence of microalbuminuria and to establish clinical characteristics associated with microalbuminuria in children with sickle cell anemia. PATIENTS AND METHODS: Urine samples of all children (homozygous SS) followed in the Medical College of Georgia's Children's Medical Center Sickle Cell Clinic were screened for microalbuminuria. Random samples were obtained from continent patients at routine office visits between September 1996 and November 1999. A retrospective chart survey was performed to determine clinical correlates for microalbuminuria. Medical records were reviewed for age, sex, hemoglobin, and episodes of pneumonia, pain, aplasia, acute chest syndrome, priapism, and avascular necrosis. Demographic and clinical variables were compared with microalbuminuria by univariate and multivariate logistic regression. RESULTS: One hundred forty-two patients ages 21 months to 20 years made up the study group. The prevalence of microalbuminuria was 19%. Both increasing age and a lower hemoglobin level were found to correlate with microalbuminuria. By multivariate analysis, boys with microalbuminuria were likely to have a lower hemoglobin level and girls with microalbuminuria were likely to be older. None of the following factors were significantly related to microalbuminuria: pain, pneumonia, acute chest syndrome, priapism, avascular necrosis, or aplastic episodes. CONCLUSIONS: Microalbuminuria is strongly and directly related to age and strongly and inversely related to hemoglobin levels. Identification of risk factors for microalbuminuria may allow earlier intervention to prevent renal complications in patients with sickle cell disease. 相似文献
33.
Promoter methylation controls the expression of MAGE2, 3 and 4 genes in human cutaneous melanoma 总被引:4,自引:0,他引:4
Sigalotti L Coral S Nardi G Spessotto A Cortini E Cattarossi I Colizzi F Altomonte M Maio M 《Journal of immunotherapy (Hagerstown, Md. : 1997)》2002,25(1):16-26
Cancer-testis antigens expressed by different-histotype transformed cells are suitable targets for tumor immunotherapy. However, their heterogeneous expression in neoplastic lesions limits the eligibility of patients for cancer-testis antigen-directed vaccination, and low levels of cancer-testis antigens' expression may impair immune recognition of malignant cells. Because of the primary clinical relevance of cancer-testis antigens' expression in neoplastic tissues, 68 unrelated or sequential metastatic lesions from 56 patients were used to characterize the molecular mechanisms regulating the presence and levels of expression of different cancer-testis antigens of the MAGE family (i.e., MAGE2, 3 and 4) in cutaneous melanoma. Polymerase chain reaction-based methylation analyses showed that methylation status of specific cytosine-guanine dinucleotides in the promoters of investigated cancer-testis antigens correlated with their heterogeneous expression within unrelated metastatic melanoma lesions, and with their homogeneous expression among sequential metastases from three patients with melanoma. Unlike methylated promoters, unmethylated promoters of MAGE2, 3 and 4 genes drove the expression of reporter gene-enhanced green fluorescent protein after transient transfection of cancer-testis antigen-positive Mel 142 melanoma cells. Furthermore, de novo expression of MAGE3 gene induced by the treatment of Mel 195 melanoma cells with the DNA hypomethylating agent 5-aza-2'-deoxycytidine was associated with a 6%-12% demethylation of selected cytosine-guanine dinucleotides in its promoter. Finally, 5-aza-2'-deoxycytidine induced a 16-fold increase of MAGE3 expression in Mel 313 melanoma cells expressing constitutively low levels of the antigen, but did not affect that of Mel 275 melanoma cells expressing high baseline levels of MAGE3. Overall, these findings identify promoter methylation as a shared mechanism directly regulating the expression of therapeutic cancer-testis antigens in metastatic melanomas, and foresee the clinical use of 5-aza-2'-deoxycytidine to design new chemoimmunotherapeutic strategies in patients with melanoma. 相似文献
34.
This study was undertaken to test the potential role of changes in lipoprotein lipase (LPL) activity in the mammary gland and adipose tissue around parturition and lactation on the uptake of alpha-tocopherol in the rat. Plasma levels of alpha-tocopherol and triglycerides were higher in 20-day pregnant rats than in virgin rats, whereas its concentration was higher in the mammary gland of the former, and no differences were detected in adipose tissue between the groups. After an oral alpha-tocopherol and triglyceride load, both appeared in plasma faster in pregnant rats than in virgin rats, the change being even faster for alpha-tocopherol than for triglycerides. After 24 hours, both alpha-tocopherol and triglycerides in d < 1.006 lipoproteins were higher in pregnant rats than in virgin rats, LPL activity was higher in the mammary gland, and lower in adipose tissue in the former, whereas alpha-tocopherol concentration also appeared higher in the mammary gland of pregnant rats, and no differences were detected between the groups in adipose tissue. At day 13 of lactation, an oral load of alpha-tocopherol and triglycerides caused a higher increase of plasma alpha-tocopherol levels than triglycerides, and this effect decreased when rats had their litter removed 48 hours before analysis. In these litter-removed rats, the appearance of alpha-tocopherol and triglycerides in plasma was higher in d < 1.006 lipoproteins than in lactating rats. Also, both LPL activity and alpha-tocopherol concentration in the mammary gland plus milk was lower in litter-removed rats than in the lactating rats, whereas LPL in adipose tissue was higher in the former, although no difference in alpha-tocopherol was found. Thus, data are consistent with the role of LPL activity in the mammary gland modulating the uptake of alpha-tocopherol during pregnancy and lactation, although this is not true in adipose tissue. 相似文献
35.
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37.
G. Gabiatti R. P. Coral O. E. Anselmi N. Da Silva Jr R. Madke T. Grezzana N. Rinaldi C. O. Corso 《Diseases of the esophagus》2008,21(6):558-562
SUMMARY. Anastomotic fistula represents one of the frequent causes of postoperative morbidity and mortality following transhiatal esophageal resections. The main etiological factor is the ischemia of the gastric tube created for digestive transit reconstruction. Evidence suggests that per operative hypoperfusion can be maintained or even impaired after the surgery. Several methods have been employed in an attempt to assess the blood perfusion of the gastric flap, but they all pose limitations. However, there is a chronological relationship between perfusion assessments, which are almost exclusively performed per operatively, and the occurrence of a leak, which commonly appears several days after the surgery. The authors have developed a method of gastric perfusion evaluation by single photon emission computed tomography scintigraphy, which corrects that temporal matter, allowing the estimation of postoperative gastric perfusion. It is noninvasive, low cost, and may be applied by the time frame when most fistulas occur. High correlation between the event fistula and the low radiotracer uptake in the group of studied patients could be demonstrated. A role in the research of perfusion evaluation of different types of esophageal reconstruction is suggested. 相似文献
38.
A S Freedman T Takvorian K C Anderson P Mauch S N Rabinowe K Blake B Yeap R Soiffer F Coral L Heflin 《Journal of clinical oncology》1990,8(5):784-791
One hundred patients with B-cell non-Hodgkin's lymphoma (NHL) in sensitive relapse or incomplete first remission underwent high-dose chemoradiotherapy and anti-B-cell monoclonal antibody (MAb)-treated autologous bone marrow transplantation (ABMT). These patients demonstrated good performance status with a Karnofsky score of 80% or greater. The majority of these patients had one or more adverse prognostic features including a failure to achieve a complete remission (CR) with conventional combination chemotherapy (37 patients), bone marrow infiltration (69 patients), a history of extranodal disease other than bone marrow infiltration (42 patients), and histologic conversion (18 patients). At the time of ABMT, only 52 patients were in CR; however, all patients achieved a minimal disease state following conventional intensive therapy. Moreover, at the time of marrow harvest, 37 of these patients had histologic evidence of lymphoma cells infiltrating the marrow. Following high-dose ablative therapy, two acute in-hospital treatment-related deaths were observed. Two late deaths were observed, not due to recurrent lymphoma. Of the remaining 96 patients, 61 are in unmaintained CR with a median follow-up of 13 months. Kaplan-Meier actuarial analysis predicts 50% probability of disease-free survival (DFS) at 37.8 months. This very low treatment-related mortality provides the rationale to apply high-dose therapy and ABMT as consolidative therapy for patients in first remission who are at high risk for relapse following conventional therapy. 相似文献
39.
J. L. Gielen M.D. M. T. van Holsbeeck M.D. D. Hauglustaine M.D. L. Verresen M.D. E. Verbeken M.D. A. L. Baert M.D. L. Meeus M.D. P. Vandevoorde M.D. P. Michielsen M.D. A. Coral M.D. 《Skeletal radiology》1990,19(1):43-49
All patients with chronic renal failure undergoing hemodialysis for more than 10 years in the university hospitals of Leuven were selected for this study. The medical records and radiographs of these 21 patients were studied retrospectively. Skeletal surveys were examined for the presence and location of subchondral cysts. The predialysis films and the films taken after 5, 10, 15 and 20 years of dialysis were reviewed. Subchondral cysts that grew in size and number were found in the wrist, humeral head, hip, and patella. Accurate measurements were made of cysts in the wrist and compared with a control group. In the dialysis group, cystic involvement of the wrist was more common and the size and number of the cysts were larger. Soft tissue swelling was seen in the dialysis group but not in controls. Soft tissue swelling was assessed on shoulder radiographs by measuring the acromiohumeral distance (ACD) and in the knees by ultrasonic measurement of synovial thickness [25]. In 11 patients synovial or bone biopsies or aspirated synovial fluid were available. All these patients had swollen joints and multiple subchondral periarticular cysts. Amyloid deposition was found in ten of these patients, and this proved to be composed of B2 microglobulins in seven (Table 1). 相似文献
40.
A metalloporphyrin-based superoxide dismutase mimic inhibits adoptive transfer of autoimmune diabetes by a diabetogenic T-cell clone. 总被引:5,自引:0,他引:5
Jon D Piganelli Sonia C Flores Coral Cruz Jeffrey Koepp Ines Batinic-Haberle James Crapo Brian Day Remy Kachadourian Rebekah Young Brenda Bradley Kathryn Haskins 《Diabetes》2002,51(2):347-355
We present here the first report of a metalloporphyrin-based antioxidant that can prevent or delay the onset of autoimmune diabetes. Type 1 diabetes is an autoimmune process whereby T-cells recognize pancreatic beta-cell antigens and initiate a leukocyte infiltrate that produces proinflammatory cytokines and reactive oxygen species (ROS), ultimately leading to beta-cell destruction. Because islet beta-cells have a reduced capacity to scavenge free radicals, they are very sensitive to ROS action. Metalloporphyrin-based superoxide dismutase (SOD) mimics scavenge ROS and protect cells from oxidative stress and apoptosis. To investigate the effect of SOD mimics and the role of oxidative stress in the development of autoimmune diabetes in vivo, we used a diabetogenic T-cell clone, BDC-2.5, to induce rapid onset of diabetes in young nonobese diabetic-severe combined immunodeficient mice (NOD.scid). Disease was significantly delayed or prevented altogether by treatment of recipient mice with an SOD mimic, AEOL-10113, before transfer of the BDC-2.5 clone. To investigate the mechanisms of protection, in vitro assays for T-cell proliferation and gamma-interferon (IFN-gamma) production were carried out using the T-cell clone BDC-2.5. We found that the SOD mimic significantly inhibited antigen-presenting cell-dependent T-cell proliferation and IFN-gamma production in vitro. In addition, pretreatment of lipopolysaccharide (LPS)-stimulated peritoneal macrophages with SOD mimic inhibited the LPS-dependent increase in TNF-alpha as well as the NADPH oxidase-dependent release of superoxide. Finally, this compound protected NIT-1 insulinoma cells from interleukin-1beta and alloxan cytotoxicity in vitro. 相似文献