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Many studies have shown that health conditions experienced in childhood play an important role on an individual's adult mortality. Recent research suggests that past reductions in early life exposure to infectious diseases have been a major contributor to the historical decline in old-age mortality. Drawing on French-Canadian data from cohorts born in the 17th and 18th centuries, we test whether a progressive deterioration in early life conditions (as revealed by an increasing infant mortality rate) translates into a decrease in survival prospects in late life. We use traditional demographic measures such as the age-specific probability of death, and a series of proportional hazard models to control for familial and environmental conditions. Results point toward little evidence of any early life effects. The trend of increasing infant mortality does not correlate with a general increase of mortality in older ages within the same cohorts. Period changes affecting survival at older ages (war, epidemics) as well as demographic and biological characteristics shared within families have a much larger role in old-age mortality than early life characteristics shared within the same cohorts.  相似文献   
23.
Summary Medical researchers must continue to develop and test non-blood oxygen-transport products. Resources provided by the Jehovah's Witness Hospital Assistance Line must be consulted. Sickle cell researchers must continue to test non-blood treatment. Information about non-blood treatments must be disbursed. Ways to enhance parental comport as the laws further and further support children's best interest must be provided. Information regarding cultural diversity must be disseminated. Hospitals and healthcare agencies that have not done so must institute the use of ethics consulting or ethics committees. Nurse ethicists must continue development of the role of educating staff; mediation, arbitration and negotiation; problem solving; obtaining legal opinion; providing patient, family, or staff advocacy; and helping to reduce suffering on the part of the providers. Difficult ethical decisions should continue to be debated.Were the staff at X Med Center correct in overriding parental wishes and breaking tenets of their faith? In the doctor's, nurse's lawyer's, and judge's view they were. The child, now eight years old, is alive and well. The stroke resolved, and imminent death averted. The parents' and child's views are not presently available. Whether the family is suffering from the child's loss of his relationship with God, or are secretly relieved in their hearts that they are not, like Rita Swan, mourning their dead son, is unknown. What is known, is that this was a difficult case for all involved, and that such cases will continue to present themselves in the future.  相似文献   
24.
Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo.  相似文献   
25.
A 15-week old male infant presented with bilateral lower motor neuron facial palsy of unknown cause. Subsequently his growth deteriorated and he developed progressively worsening cough and wheeze. A diagnosis of cystic fibrosis was confirmed and hypovitaminosis A detected. Improvement of the facial palsy was noted following standard management of cystic fibrosis including vitamin A supplementation.  相似文献   
26.
OBJECTIVE: To develop an assay that measures the concentration of functional neutrophils in human semen. DESIGN: Human blood neutrophils were first isolated to establish linearity and proportionality for the determination of functional neutrophil concentration. Thereafter blood neutrophils in seminal plasma and neutrophils in semen of patients were measured. SETTING: Blood and human samples were obtained from clinics of the Royal Victoria Hospital. PATIENTS, PARTICIPANTS: Blood from normal men or from patients presenting with chest pain or trauma were used. Semen samples were also obtained from healthy fertile donors or from unselected patients attending the infertility clinic. MAIN OUTCOME MEASURES: Active neutrophil concentration in semen by a colorimetric assay. RESULTS: The assay developed is based on the reduction of nitroblue tetrazolium of pale yellow color to blue formazan by the superoxide anions produced by stimulated neutrophils. The intensity of the derived blue color is proportional to the concentration of active neutrophils. This assay is simple, requires only 10 minutes of preparation time, and detects neutrophil concentrations greater than 0.5 x 10(6) neutrophils/mL of semen, independent of sperm concentration.  相似文献   
27.
Abstract: We performed a retrospective analysis of clinical course of 91 patients who developed both breast cancer and a chronic lymphoproliferative neoplasm and were seen at the M. D. Anderson Cancer Center between January 1, 1970 and December 30, 1991. The sample included 24 individuals who developed lymphoproliferative neoplasm first (Group A), 22 individuals with concurrent diagnosis of both malignancies (Group B), and 45 individuals who developed breast cancer first (Group C). The median time to diagnosis of secondary breast cancer and lymphoproliferative neoplasm was 66 months (range, 7–459) and 65 months (range, 0–334), respectively. A higher proportion of Group B lymphomas were low-grade (77% vs. 47% [Group A] vs. 37% [Group C] p = 0.009). Prior occurrence of either one of these malignancies did not affect the disease-specific survival from the second malignancy. However, continuing mortality from the first malignancy appeared to contribute to a poor overall survival following second malignancy. Group A included 8 patients who developed breast cancer following radiation therapy for Hodgkin's disease after a mean interval of 18 (± 4.3) years. Three of these individuals had coexisting ductal and lobular histology (vs. none of the individuals in Groups B and C, p = 0.02). Another interesting finding was the high incidence of multiple additional malignancies in this patient population. A total of 29 additional neoplasms occurred in 21 (23%) of the 91 study subjects. These malignancies involved a wide variety of organ sites and could not be attributed to the therapy for either the breast cancer or the lymphoma in most cases. The data suggest that individuals who develop both breast cancer and a lymphoproliferative neoplasm are at a high risk for multiple malignancies. Close surveillance of such individuals for additional malignancies and further studies to understand the molecular basis of this predisposition are warranted.?  相似文献   
28.
One hundred six undergraduate (83 women and 23 men) completed surveys concerning their most traumatic life event, the feedback they received following their disclosure of the event to others, and how they felt after the disclosure. Results indicated that the better they felt after disclosure, the less disturbed they were by thoughts of the event at the time of the study. In addition, the more personal the trauma was, the worse they felt after their disclosure, and the more disturbed they were about the trauma. However, no significant relation existed between the positivity (e.g., supportiveness) of their confidant's feedback and their present degree of disturbance. Implications for understanding the complex relation between confiding traumatic events and resolving feelings surrounding those events were discussed.  相似文献   
29.
Family resources in terms of their qualitative (process) and quantitative (structure) nature influences the development of social competence in children/adolescents. Present study aims at exploring the relationship of family resource variables with three measures of social competence of 300 adolescent belonging to different socio-cultural status. Socio-culturally advantaged group samples were found to have healthy family environment, whereas, socio-culturally disadvantaged group perceived themselves as at disadvantages and were deprived in seeking positive intra-family support. However inspite of their disadvantages, they were found to be more self-competent. On the other hand, advantaged group adolescents were found to be more competent in the areas of peer and teacher related social competence. Product-moment coefficient correlation analysis revealed that parental education, occupation and family income were found to be significantly associated with positive peer and teacher related social competence in case of the samples belonging to the advantaged socio-cultural group. However, negative responses and outside family support was found to be positively associated with the development of disadvantaged group adolescent's self-related competence. In general, present study supports the hypothesis that Indian family system still continues to be considered as the major source of support for the adolescents, in spite of their growing tendency for independence, self-definition and autonomy.  相似文献   
30.
Acquired immunodeficiency syndrome (AIDS) is a serious disease that has special concern for the health care provider. AIDS has continued to grow despite control efforts. As the disease infectivity period remains lengthy, and the heterosexual population is affected to a greater degree, the level of anxiety has also risen despite educational endeavours. Many fears and anxieties have been associated with AIDS patients by health care workers. The reduction of stress, perceived risk and discomfort following educational efforts have been supported in past research. Educational programmes will need to be given for current health care workers at all levels as well as nursing students. Future nurses must be prepared to meet this challenge. This study was conducted using a convenience sample of nursing students at a university in western United States. Its purpose was to assess any changes that occurred in state anxiety following an educational presentation. Spielberge's State-Trait Anxiety Inventory was used as the measurement instrument. Some anxiety levels were significantly reduced.  相似文献   
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