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Parents play a crucial role in the life of a child suffering from an anorectal malformation (ARM), since their guidance contributes to the degree to which the child learns to cope with his or her disability. We investigated whether they experience stress in parenting such a child and also attempted to identify somatic or behavioral characteristics in the child that influence the stress of parenting. The parents of 109 children (69 males, 40 females; median age 5.9 years, range 1-18 years) with an ARM (58 low, 10 intermediate, 41 high) were studied. The Nijmegen Questionnaire on Child-rearing Situations (NQCS) was used to investigate the existing parenting situation. Behavioral characteristics of the children were studied by means of the Child Behaviour Checklist (CBCL) and the Teacher Report Form (TRF). In a semi-structured interview, we investigated how parents experienced the implications of the disability in everyday life with their child. Our study showed that as far as the perception of parenting stress is concerned, parents of children with an ARM do not differ from those with healthy primary-school children. Within the group of parents with ARM-afflicted children, the parents of older, incontinent children experienced relatively more stress, especially when the child concerned was male. With regard to the children's behavior, the parents and teachers under investigation did not report a higher than normal incidence of deviant behavior. However, when individual parents observed difficult behavior in their child, they found it harder to deal with than the incontinence for feces. Regarding the implications of the disorder for their everyday lives, parents were concerned and indicated a need for specific counselling. We conclude that having a child with a somatic affliction, in this case an ARM, does not automatically imply that the parents experience child-rearing problems. However, certain groups of parents are more at risk, i.e., parents with older, incontinent sons and parents with children exhibiting behavioral problems. In addition, our study shows that parents do have difficulties in coping with the implications of the disorder and express a need for support. We feel that patient care can be improved if aid is tailored to these specific problems.  相似文献   
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BACKGROUND AND OBJECTIVE: Intensive induction and post-remission therapies have improved the prognosis in adult acute lymphoblastic leukemia (ALL). However, different from children, the impact of late intensification therapy in the overall results of treatment has not been consistently evaluated. The objective of this study was to analyze the results of a multicenter prospective protocol, PETHEMA ALL-89, in which, after intensive induction and consolidation therapy, randomization to receive delayed intensification treatment was performed. DESIGN AND METHODS: One hundred and eight adults (age > or = 15 years) diagnosed with ALL (ALL L3 excluded) in 22 Spanish hospitals from 1989 to 1994 were treated with a five-drug induction therapy, followed by four cycles of early post-remission treatment during four months, and maintenance therapy for two years. Patients in remission at the end of the first year were randomized to receive one six-week cycle of late intensification therapy. Uni- and multivariate analyses of early response to treatment, complete remission (CR), leukemia-free survival (LFS) and overall survival (OS) were performed. RESULTS: The median (range) age of the series was 28 (15-74) years and leukocyte count 26 x 10(9)/L (1-600). ALL L1/L2 was present in 38/70 patients, early pre-B in 13, common in 53, pre-B in 12 and T in 30 cases. The CR rate was 86%, and refractory disease 9%. Median LFS was 34 months, with a 5-yr probability of 41% (95% CI, 29-53), whereas median OS was 51 months and 5-year probability 47% (34-59%). There were no differences in either LFS and OS between patients who did or did not receive delayed intensification therapy. Prognostic factors for CR attainment were advanced age and slow response to therapy. These two features were, in addition to high leukocyte counts, the parameters with negative influence in both LFS and OS. INTERPRETATION AND CONCLUSIONS: The results of PETHEMA ALL-89 are similar to those referred in other chemotherapy-based protocols in adult ALL. Delayed intensification has not improved the length of remission and survival. Efforts to improve the prognosis of adult ALL patients must be mainly focused in early intensification treatment.  相似文献   
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Although most short, linear peptide fragments of proteins are unstructured in aqueous solution, a number of immunogenic and antigenic peptides have been shown to have conformational preferences for structured forms. By using mainly NMR and CD spectroscopy, it has been possible to detect and quantify quite small populations of beta-turn, helical, and nascent helical conformations. Recent studies have been published indicating that the presence of structured forms is correlated with the location of T cell and/or B cell epitopes in peptide sequences. X-ray crystal structures of complexes between peptides and anti-peptide antibodies frequently show the peptides bound in beta-turn conformations, and the presence of helix in one peptide-antibody complex has been shown by NMR spectroscopy. Studies of peptides free in solution and bound to anti-peptide antibodies in the crystal indicate that the structure of the principal neutralizing determinant of HIV-1 probably includes at least one beta-turn in a highly conserved region. These results can potentially be used in the design of peptide-based vaccines.  相似文献   
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Delayed aorto-pulmonary artery fistula represents an uncommon delayed sequelae of penetrating cardiac trauma. A case is presented that demonstrates the need for a high index of suspicion, follow-up, and a complete evaluation of the patient who survives a penetrating heart injury. The mechanisms of delayed presentation, diagnosis, and management of the fistula are discussed.  相似文献   
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The interrelationship between cytokines and their natural antagonists in patients with systemic sepsis are incompletely understood. We have followed the changes in serum levels of TNF-alpha and the two soluble receptors (TNF-sr) in a clinical model of post-operative sepsis. Serial blood samples were taken in patients undergoing percutaneous nephrolithotomy (PCNL) starting pre-operatively and continuing for 24 h thereafter. The levels of TNF-alpha and TNF-sr were raised in patients who became clinically septic and correlated well with the severity of sepsis (using the APACHE III score). In septic patients there was no difference in the pattern of changes in the two types of receptor (TNF-sr55 and TNF-sr75). However, in non-septic patients TNF-sr75 was higher in those with endotoxaemia than those without. This difference was not observed with TNF-sr55 which suggests a different mechanism of release or degree of sensitivity for the two soluble receptors. Regardless of severity of illness, the levels of all three molecules (TNF-alpha and the two receptors) appeared to start rising at about the same time point. The peak TNF-alpha level was reached earlier (2-4 h) than that of the two TNF-sr (4-8 h). The relative rise in TNF-alpha was greater than that of the soluble receptors and this difference was even more marked in those with more severe sepsis. The relationship between peak TNF-alpha and peak TNF-sr was non-linear and the concentration of each TNF-sr appeared to plateau at the higher levels of TNF-alpha. This suggests the exhaustion of a limited pool or saturation of the rate of release. Taken together, these results suggest sepsis develops because of delayed and insufficient secretion of TNF-sr compared with TNF-alpha.  相似文献   
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The treatment of rats with hepatotoxic doses of hydrazine (NH2-NH2) induces the rapid formation of 7-methylguanine and O6-methylguanine in liver DNA. The methyl moiety in these reactions might be derived from the cellular S-adenosylmethionine pool because radioactivity administered to these rats as methionine rapidly appears in the DNA as methylated guanine. An increased incorporation of radioactivity into 5-methylcytosine was previously reported followed by subsequent suppression. This increased radiolabeling of 5-methylcytosine coincided with time of maximal DNA guanine methylation. To determine the nature of S-adenosylmethionine metabolism during the period of DNA methylation induced by hydrazine treatment, and to determine if the increased radiolabeling of 5-methylcytosine at this time reflected an actual increase in 5-methylcytosine synthesis, liver DNA synthesis and S-adenosylmethionine levels and turnover were assayed. Liver S-adenosylmethionine concentrations varied slightly between control rats and hydrazinetreated rats during the first five hours after hydrazine administration, and no difference was detectable in the incorporation of administered [3H]methionine into S-adenosylmethionine. Because S-adenosylmethionine specific radioactivity in hydrazine-treated rats was not different from control rats, the previously observed increased radiolabeling of 5-methylcytosine appeared to represent an actual increase in synthesis. This conclusion was supported by finding that incorporation of radioactive thymidine into DNA was also accelerated immediately following hydrazine administration, again followed by a decrease. 5-Methylcytosine sythesis, therefore, appears to follow DNA synthesis during hydrazine toxicity, and formation of 7-methylguanine and O6-methylguanine in liver DNA of hydrazine-treated rats occurs during a short period of increased DNA sythesis and 5-methylcytosine formation very early in hydrazine toxicity.  相似文献   
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The phosphorylation state of three identified neural-specific protein kinase C substrates (RC3, GAP-43/B-50, and MARCKS) was monitored in hippocampal slices of mice lacking the gamma-subtype of protein kinase C and wild-type controls by quantitative immunoprecipitation following 32Pi labeling. Depolarization with potassium, activation of glutamate receptors with glutamate, or direct stimulation of protein kinase C with a phorbol ester increased RC3 phosphorylation in wild-type animals but failed to affect RC3 phosphorylation in mice lacking the gamma-subtype of protein kinase C. Our results suggests the following biochemical pathway: activation of a postsynaptic (metabotropic) glutamate receptor stimulates the gamma-subtype of protein kinase C, which in turn phosphorylates RC3. The inability to increase RC3 phosphorylation in mice lacking the gamma-subtype of protein kinase C by membrane depolarization or glutamate receptor activation may contribute to the spatial learning deficits and impaired hippocampal LTP observed in these mice.  相似文献   
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