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51.
52.
Sixty-seven out of 105 (64%) adults with de novo acute myelogenous leukemia (AML), achieving complete remission after induction chemotherapy, entered two successive postremission treatment protocols. Between 1987 and 1989, 35 patients received an intermediate dose of cytarabine (IDAC) along with other drugs. Between 1990 and 1993, 32 patients received high dose cytarabine (HIDAC) with similar other drugs. Patients treated with IDAC had a median survival of 13.8 months (95% Cl 11.2–23.1 months) and a 2 year survival of 34.3 ± 8.0%. Patients receiving HIDAC had a median survival of 35.5 months (95% Cl, lower limit 29.8 months) and a 2 year survival of 71.6 ± 9.4% (P < 0.002). The 2 year actuarial leukemia-free survival (LFS) was 17.8 ± 6.6% in the IDAC group and 67.3 ± 10.0% months in the HIDAC group (P = 0.004). The HIDAC group had a significant 2 year survival advantage over the IDAC group only in patients younger than 45 years. The 2 year survival in the first group was 83.3 ± 10.8% versus 23.5 ± 10.3% in the IDAC group (P = 0.0001). In patients older than 45 years, no significant differences in 2 year survival was noticed (52.9 ± 15.78 versus 44.4 ± 11.7, P = 0.8). Censoring the 21 patients who underwent bone marrow transplantation (BMT) at BMT did not change significantly the survival analysis of the patients in each group. This study is consistent with previous reports favoring HIDAC intensification in the postremission treatment of young patients with AML.  相似文献   
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Anesthesiologist board certification and patient outcomes   总被引:7,自引:0,他引:7  
BACKGROUND: Board certification is often used as a surrogate indicator of provider competence, although few outcome studies have demonstrated its validity. The aim of this study was to compare the outcomes of patients who underwent surgical procedures under the care of an anesthesiologist with or without board certification. METHODS: Medicare claims records for 144,883 patients in Pennsylvania who underwent general surgical or orthopedic procedures between 1991 and 1994 were used to determine provider-specific outcome rates adjusted to account for patient severity and case mix, and hospital characteristics. Outcomes of 8,894 cases involving midcareer anesthesiologists, 11-25 yr from medical school graduation, who lacked board certification were compared with all other cases. Midcareer anesthesiologist cases were studied because this group had sufficient time to become certified during an era when obtaining certification was already considered important, and consequently had the highest rate of board certification. Mortality within 30 days of admission and the failure-to-rescue rate (defined as the rate of death after an in-hospital complication) were the two primary outcome measures. RESULTS: Adjusted odds ratios for death and failure to rescue were greater when care was delivered by noncertified midcareer anesthesiologists (death = 1.13 [95% confidence interval, 1.00, 1.26], P < 0.04; failure to rescue = 1.13 [95% confidence interval, 1.01, 1.27], P < 0.04). Adjusting for international medical school graduates did not change these results. CONCLUSIONS: When anesthesiology board certification is very common, as in midcareer practitioners, the lack of board certification is associated with worse outcomes. However, the poor outcomes associated with noncertified providers may be a result of the hospitals at which they practice and not necessarily their manner of practice.  相似文献   
55.
The purpose of this study was to characterize the sleep patterns of children with intrauterine growth retardation, known to be at risk for neurodevelopmental disorders, and seek a possible correlation with behavior, concentration, and attention problems. The sleep patterns of 26 children with intrauterine growth retardation aged 4 to 7 years were compared with those of 47 control children using activity monitors (actigraphs). In addition, data were collected from the parents regarding sleep habits, behavior, concentration, and attention. Children with intrauterine growth retardation aged 4 to 7 years were found to have a tendency toward poorer quality of sleep than their matched controls. This inclination was statistically significant only for one sleep measure, the true sleep time. A tendency toward increased fragmentation of sleep, prolonged waking, and decreased sleep efficiency, although not statistically significant in this study, was demonstrated. Our results showed that 58% of the children with intrauterine growth retardation, compared with 40% of the children in the control group, could be defined as "poor sleepers" (sleep efficiency lower than 90% or three or more waking episodes per night). This disturbed sleep profile is probably an integral part of the neurodevelopmental profile typical of these at-risk children. No significant correlations were found between sleep quality and behavior, concentration, and attention problems.  相似文献   
56.
Cleavage of heparan sulphate proteoglycans (HSPGs) affects the integrity and functional state of tissues and thereby fundamental normal and pathological phenomena involving cell migration and response to changes in the extracellular microenvironment. Heparanase, degrading heparan sulphate (HS) at specific intrachain sites, is synthesized as a latent approximately 65 kDa protein that is processed at the N-terminus into a highly active approximately 50 kDa form. The heparanase enzyme is preferentially expressed in human tumours and its overexpression in low-metastatic tumour cells confers a highly invasive phenotype in experimental animals. Heparanase also releases angiogenic factors and accessory fragments of HS from the tumour microenvironment and induces an angiogenic response in vivo. Heparanase may thus facilitate tumour cell invasion, vascularization and survival in a given microenvironment, all critical events in cancer progression. These observations, the anticancerous effect of heparanase-inhibiting molecules, and the unexpected identification of a single predominant functional heparanase suggest that the enzyme is a promising target for drug development.  相似文献   
57.
Recent evidence demonstrates that there are sex differences in behavioral responses to cocaine. Further, reproductive gonadal hormones (estrogen, progesterone and testosterone) have been further implicated in mediating some of the cocaine-induced alterations. To better understand sex differences and the role of gonadal hormones in cocaine-induced locomotor and stereotypic behavior, intact and gonadectomized male and female Fischer rats were randomly assigned to either chronic cocaine (15 mg/kg) or saline treatments for 14 days followed by a challenge administration (7 days after the last cocaine/saline administration). Locomotor (ambulatory and rearing) and stereotypic activities were measured on days 1, 7 and 14 as well as after withdrawal/challenge with cocaine. Overall, intact female rats consistently showed a rapid (acquired by day 7) and longer lasting (persistent through the challenge dose) sensitization for all locomotor behaviors than any of the other groups. In contrast, intact males developed sensitization of these locomotor activities only in response to chronic cocaine administration, and after withdrawal and drug challenge the sensitization to cocaine-induced locomotor activity was no longer present. In female rats, gonadectomy affected ambulatory activity but not total and rearing responses after acute, sub-acute, chronic and challenge response to cocaine. On the other hand, castrated male rats were affected in cocaine-induced ambulatory activity but not rearing activity. In intact male rats, cocaine-induced stereotypic activity was rapidly and persistently sensitized after 7 days of cocaine administration, where gonadectomized male rats developed sensitization to cocaine-induced stereotypic activity only after a challenge cocaine administration. Although cocaine induced stereotypic activity, no statistically significant differences were observed between intact and ovariectomized female rats or throughout the different lengths of cocaine administration. After a challenge of cocaine, corticosterone levels were induced in all experimental groups. Moreover, no differences in levels of benzoylecgonine, a cocaine metabolite, were observed. Similar to our previous observations after acute cocaine administration, after challenge of cocaine, an increase in progesterone and a decrease in testosterone levels were observed in intact females and males, respectively. In summary, endogenous hormones seem to be involved in the behavioral activation and development of sensitization to cocaine.  相似文献   
58.
The transplantation of organs, which at first sight appears to be just a technical medical procedure, is, first and foremost a sociocultural action that gives expression to existential perceptions. In Israeli society, as in most western societies the donation of the body or parts of it, is interpreted as possible at a societal level, and not as a gift from one individual to another. The medical achievement inherent in organ transplantation brings forward the relationship between the body, death and society. The moment the body ceases to function biologically, its position within the social entity is examined. The donation of organs evinces the acceptance of the idea that the personal body belongs to the society which sanctions the transition of the private body into organs that become national assets. This research is a first attempt to study the motives of people from Muslim society, who donated organs of their dear ones. The ability of these people to enter into a system of exchange flows from a tacit assumption by all of them that the action is approved by their social group. This paper presents the concepts of death and of the body that enable donation in general and the donation of the Muslim population in particular.  相似文献   
59.
Introduction: Positive outcomes in the aftermath of childbirth have increasingly been studied in the last decade. However, most of the studies concentrate on short-term outcomes. The current study examined the perceived personal growth of mothers four years after childbirth, investigating the contribution of the event characteristics (full-term/pre-term birth), internal resources (optimism, self-esteem) and personal growth as measured one year after the birth.

Methods: Mothers (n=259) participated in the study by completing a set of self-report questionnaires one and four years following the birth of their child/ren.

Results: Personal growth after four years was found to be higher among mothers of pre-terms than of full-terms, and higher four years after the birth than it had been three years earlier. Furthermore, regression analysis indicated the significant contributions of being a mother to pre-term baby/ies, optimism and personal growth one year after the birth to women’s personal growth three years later.

Discussion: The results highlight the potential long-term effects of giving birth to a pre-term baby on personal growth, as well as the contribution of optimism as an important internal resource. They also indicate the development of personal growth over time. Explanations for the findings are offered and their practical implications are discussed.  相似文献   

60.
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