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To evaluate the catabolic effects of dexamethasone therapy on protein metabolism, amino acid concentrations and urinary 3-methylhistidine (3MH) were measured in 28 premature infants who were included in a double-blind controlled study using early dexamethasone therapy in the prevention of bronchopulmonary dysplasia. Fifteen infants received dexamethasone (0.5mg/kg/day i.v.) and 13 infants received normal saline as control. Heparinized venous blood samples for amino acid analysis were obtained before the study and again at day 5 after starting the study. Urinary 3MH was measured on days 1, 3, 5, 7, 14, 21, and 28 of treatment. A substantial increase in amino acid concentrations was observed in infants receiving dexamethasone. Alanine, glutamine, citrulline, ornithine and cystine concentrations increased twofold or more. The 3MH:creatinine ratio was increased in the treated group. These metabolic effects were most likely due to an increase in protein catabolism.  相似文献   
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R C Ribeiro  C H Pui  M J Schell 《Cancer》1988,61(3):589-592
Twenty-four (1.6%) of 1466 children with acute lymphoblastic leukemia (ALL) treated at St. Jude Children's Research Hospital had vertebral compression fractures at diagnosis. When compared with patients without this complication, they were more likely to have good prognostic features, including a leukocyte count of greater than 25 X 10(9)/l, a leukemic cell DNA index of greater than 1.15, and hyperdiploidy (greater than 50 chromosomes). Complete remission of ALL was induced in all patients, and symptoms of vertebral compression fractures abated following antileukemia therapy. Although the diagnosis of ALL was delayed for some patients because this unusual presenting complication was not recognized as such, their treatment outcome was as good as that for other children with "standard-risk" ALL.  相似文献   
4.
Chen YH  Lee MF  Lan JL  Chen CS  Wang HL  Hwang GY  Wu CH 《Allergy》2005,60(12):1518-1523
BACKGROUND: Forcipomyia taiwana is a tiny, blood-sucking midge that cause intense pruritis and swelling in sensitive individuals. It is distributed island-wide in rural Taiwan and Southern China. Objective: This study aimed to study the allergic immune responses and identify F. taiwana allergens. METHODS: Crude whole body F. taiwana extracts were prepared with phosphate-buffered saline. The specific IgE antibody was determined by enzyme-linked immunoassay and immunoblotting. Protein was analyzed by electrospray ionization tandem mass spectrometry. RESULTS: Among the 372 subjects that were exposed to F. taiwana bites, 179 (48%) reported an immediate skin reaction with/without delay reaction and 41(11.1%) reported a solely delay reaction. The skin of 21 subjects was tested with F. taiwana extract. Of these 21 subjects, 12 (57.1%) produced immediate skin reactions and contained high levels of specific IgE antibody against F. taiwana. Immunoblotting revealed that 11 allergenic components are able to bind specific IgE. Allergens of 22, 24, 35, 36, and 64 kDa bound 50, 50, 75, 66.7, and 75% of IgE-containing sera tested, respectively. Tryptic fragments of the 24, 35, 36, and 64 kDa allergens were analyzed by ESI-MS/MS. Selected tryptic peptides of 24, 35, and 36, and 64 kDa allergens exhibited significant sequence identity with triosephosphate isomerase of Anopheles merus,Tenebrio molitor,Ochlerotatus togoi, and Chrysops vittatus, fructose 1,6-bisphosphate aldolase of Antheraea yamamai and Homalodisca coagulata, and a slow muscle myosin S1 heavy chain of Homarusamericanus and a protein with unknown function from A. gambiae, respectively. The 35 and 36 kDa proteins may represent different isoforms of the fructose 1,6-bisphosphate aldolase. CONCLUSION: We conclude that immediate reaction to F. taiwana bites is IgE mediated and the 24 (For t 1), 35 (For t 2), and 64 kDa (For t 3) proteins are candidates for major F. taiwana allergens. Further studies are needed to confirm these allergens.  相似文献   
5.
Despite the abundant evidence of high allelic loss of chromosome arm 14q in human cancers, tumor-suppressor genes mapped to this chromosome have yet to be identified. To narrow the search for candidate genes, we performed monochromosome transfer of chromosome 14 into an esophageal carcinoma cell line, SLMT-1 S1. Statistically significant suppression of the tumorigenic potential of microcell hybrids containing the transferred chromosome 14 provided functional evidence that tumor-suppressive regions of chromosome 14 are essential for esophageal cancer. Tumor segregants emerging in nude mice during the tumorigenicity assay were analyzed by detailed PCR-microsatellite typing to identify critical nonrandomly eliminated regions (CRs). A 680-kb CR mapped to 14q32.13 and an approximately 2.2-Mb CR mapped to 14q32.33 were delineated. Dual-color BAC FISH analysis of microcell hybrids and tumor segregants verified the selective loss of the 14q32.13 region. In contrast, similar transfers of an intact chromosome 11 into SLMT-1 S1 did not significantly suppress tumor formation. These functional complementation studies showing the correlation of tumorigenic potential with critical regions of chromosome 14 validated the importance of the 14q32 region in tumor suppression in esophageal cancer. The present study also paved the path for further identification of novel tumor-suppressor genes that are relevant to the molecular pathogenesis of esophageal cancer.  相似文献   
6.
This clinical study, begun in 1975, tested the efficacy of early and delayed intensification treatments in children with acute lymphoblastic leukemia. Regardless of presenting features, all patients received 4 weeks of conventional induction therapy with daily prednisone and weekly vincristine and daunorubicin. One-third were randomized to receive, in addition, two doses of asparaginase during induction therapy, while another one-third received four doses of both asparaginase and cytarabine after remission induction. Preventive central nervous system therapy uniformly included 2400 rads cranial irradiation and five doses of intrathecal methotrexate. Remissions were maintained with daily p.o. mercaptopurine and weekly i.v. methotrexate. Of the 277 assessable patients, 254 (92%) entered complete remission, and 102 (37%) remain clinically free of leukemia for 4.6 to 8.0 years (median, 6.3 years). The three treatment groups showed no significant differences in either remission induction rate or outcome, even when the analysis was based on risk assignment. A "late intensification" phase of therapy, added to the maintenance protocol for 65 patients who had been in continuous complete remission for 14 to 30 months, failed to extend remission durations, as judged from statistical comparison with matched controls (p = 0.84). When tested as a time-dependent covariate in the Cox proportional-hazards model, delayed intensification again showed no important effect on duration of complete remission. We conclude that limited early or aggressive late intensification of therapy, as described here, does not improve outcome in childhood acute lymphoblastic leukemia.  相似文献   
7.
Hu  Huagang  Liu  Xu  Chau  Pui Hing  Choi  Edmond Pui Hang 《Quality of life research》2022,31(7):1915-1932
Quality of Life Research - To summarize the current evidence regarding the effectiveness of intradialytic exercise (IDE) on the health-related quality of life (HRQOL) of patients undergoing...  相似文献   
8.
BACKGROUND: After presenting two sisters with the rare form of congenital arrhinia, this syndrome is reviewed, an explanation of the pathogenesis is offered and the therapeutic options of the functional and aesthetic reconstruction are discussed. DISCUSSION: In cases of congenital arrhinia different degrees of respiratory distress, cyanotic episodes, and impaired food intake are described. Therefore after birth respiration and food intake need to be monitored to alleviate the situation through intubation or tracheotomy. The following conclusions could be made based on the literature overview. Little is known about the pathophysiology and a great variety of therapeutic interventions and reconstruction solutions with a wide spectrum of complications are described. Due to the numerous forms of complications, which need to be compared with the reconstructive results, indications for surgical reconstruction of the airway and plastic reconstruction of the nose during childhood must be defined very stringently. CONCLUSION: One method to achieve a satisfactory plastic result is with an osseointegrated prosthesis. This facial prosthesis can be inserted without complications and can guarantee an adequate result, whereas no impairment of maxillofacial development was noted.  相似文献   
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