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371.
Quantitative and temporal progestin profiles vary during gestation in the elephant, sometimes making it difficult to determine if a pregnancy is progressing normally. The aim of the present study was to determine if circulating progestin variability was related to species or fetal gender effects. A similar comparison also was conducted for secretory profiles of prolactin, relaxin, and cortisol. Overall mean progestin concentrations during gestation in Asian (n = 19) and African (n = 8) elephants were similar; however, the temporal profiles differed (P < 0.001). Concentrations were higher in African elephants during the first half of pregnancy, but then declined to levels below those observed in Asian elephants (P < 0.05). There also was a fetal gender effect in Asian, but not African elephants. Progestin concentrations were higher in Asian cows carrying male calves (n = 9) as compared to those carrying females (n = 10) (P < 0.001). Overall prolactin concentrations were higher in Asian than in African elephants between 8 and 15 months of gestation ( P< 0.001). There were no species differences in the secretory patterns of relaxin. Cortisol was relatively stable until the end of gestation when significant surges were observed, mainly between 8 and 11 days before parturition, and again on the day of birth. In sum, a comparison of progestin patterns between Asian and African elephants identified notable differences related to species and fetal gender. A role for cortisol in the initiation of parturition also was inferred from these data. From a practical standpoint, understanding the factors affecting gestational hormone characteristics and recognizing what the species differences are will help ensure that data used in diagnosing and monitoring elephant pregnancies are properly interpreted.  相似文献   
372.
The sharp increase in the prevalence of asthma over the past three decades suggests an important contribution of environmental factors in the generation of this disease, and compels a search for molecular pathways by which such factors could facilitate Th2 immune-inflammatory airway responses; granulocyte-macrophage colony-stimulating factor (GM-CSF) might be one such signal. In this review, we appraise the evidence with respect to the presence of GM-CSF in asthma, the roles played by GM-CSF in these immune responses and environmental triggers that can induce GM-CSF expression. Further, we propose a paradigm that unites these divergent observations, and postulate that GM-CSF produced in response to environmental agents can establish an airway microenvironment that promotes the initiation, influences the evolution and supports the maintenance of an aeroallergen-specific adaptive Th2 immune response.  相似文献   
373.
We analyzed the temporal changes in the caseload of primary and revision hip and knee arthroplasty surgeons in the United States between 1990 and 2004. The Nationwide Inpatient Sample was used to identify arthroplasty procedures and the surgeons who performed them. Annual caseloads were analyzed for each procedure; 47% +/- 2% and 39% +/- 2% of hip and knee surgeons performed revisions nationwide. Average revision caseloads increased slightly over time at a rate of 1.2 and 1.4 cases per surgeon per decade for total hip arthroplasty (THA) and total knee arthroplasty (TKA), respectively. The caseload of primary THA and TKA increased by 1.4 and 1.7 cases per surgeon per decade. The caseload for the top 5% of primary THA and TKA surgeons increased from 25 to 45 and 33 to 86, respectively, during this period compared with the median caseload, which increased from 4 to 5 (hip) and 5 to 10 (knee). The revision caseload of surgeons has increased over time, particularly for surgeons with the highest caseloads.  相似文献   
374.
As the prevalence of obesity increases, its economic consequences must be understood. This review summarizes published literature on the costs and resource use associated with obesity in the workplace. A Medline literature search was conducted for English-language publications. References from identified articles were also reviewed for relevance. The identified studies evaluated several cost components, including absenteeism, sick leave, disability, injuries, and claims data. Overall, overweight or obese employees had higher sick leave or disability use. Workplace injuries were higher among overweight or obese employees. Health care costs, based on claims data analyses, were also consistently higher for employees with higher body mass indices. Obesity is an important driver of costs in the workplace. These findings quantify the costs and can help employers consider whether to introduce workplace interventions or provide coverage for weight loss programs.  相似文献   
375.
BackgroundSevere obesity is frequently a barrier to kidney transplantation, and kidney transplant recipients often have significant weight gain following transplantation.ObjectivesThe goals of this study were to evaluate the long-term risks and benefits of bariatric surgery before and after kidney transplantation.SettingUniversity Hospital, United States.MethodsWe performed a retrospective cohort study of 43 patients who had pretransplantation bariatric surgery and 21 patients who had posttransplantation bariatric surgery from 1994 to 2017 with propensity-score matching to identify matched controls using national registry data.ResultsBody mass index at the time of transplantation was similar in patients who underwent bariatric surgery before versus after transplantation (32 versus 34 kg/m2, P = .172). There was no significant difference in body mass index in the 5 years after bariatric surgery among patients who underwent bariatric surgery before versus after kidney transplantation (36 versus 32 kg/m2, P = 0.814). Compared with matched controls, bariatric surgery before (n = 38) and after (n = 18) kidney transplantation was associated with a decreased risk of allograft failure (hazard ratio .31 [95% confidence interval .29–0.33] and .85 [95% confidence interval .85–.86] for pre- and posttransplant, respectively) and mortality (hazard ratio .57 [95% confidence interval .53–.61] and .80 [95% confidence interval .79–.82] for pre- and posttransplant, respectively).ConclusionsBariatric surgery before and after kidney transplantation results in similar maintenance of weight loss and improved long-term allograft survival compared with matched controls. Bariatric surgery appears to be a safe and reasonable approach to weight loss both before and after transplantation.  相似文献   
376.

Introduction

In this work we want to know the long-term rates of locoregional recurrence and distant metastasis in a population of breast cancer patients with pT1–pT2 tumours and one to three positive lymph nodes who were treated with mastectomy and axillary lymphadenectomy, and to study the relationship of certain clinical and histopathological parameters to their development.

Material and methods

Ninety patients diagnosed with a breast tumour of less than 5 cm and one to three affected lymph node, and undergoing a modified radical mastectomy with axillary lymphadenectomy, were studied. The mean overall follow-up was 132 months, and the minimum follow-up for the living patients was 10 years. Locoregional recurrence and metastasis development rates were studied and clinical and pathological parameters were evaluated.

Results

We found locoregional recurrence in 22.5% of the patients, and systemic metastases in 30.3%. In the study of locoregional recurrences significant differences were found for tumour size (T2) (p=0.001) and metastasis were more frequent with extracapsular lymph node extension (p=0.02) and non-administration of chemotherapy (0.019).

Conclusions

The parameter related to the development of locoregional recurrence was tumour size (stage T2) and those related to the development of metastasis were extracapsular lymph node extension and non-administration of chemotherapy.  相似文献   
377.
There is a common view that one of the major considerations in selecting between universal and indicated interventions is the marked stigma produced by the latter. However, to date there has been no empirical examination of this assumption. The current study examined reported stigma and program satisfaction following two school-based interventions aimed at preventing depression in 532 middle adolescents. The interventions were conducted either across entire classes by classroom teachers (universal delivery) or in small high risk groups by mental health professionals (indicated delivery). The indicated delivery was associated with significantly greater levels of perceived stigma, but effect sizes were small and neither program was associated with marked stigma in absolute terms. Perceived stigma was more strongly associated with aspects of the individual including being male and showing greater externalizing symptomatology. In contrast, the indicated program was evaluated more positively by both participants and program leaders and effect sizes for these measures of satisfaction were moderate to large. The results point to the need for further empirical evaluation of both perceived stigma and program satisfaction in providing balanced considerations of the value of indicated and universal programs.  相似文献   
378.
In light of the abruptness and severity of the HIV/AIDS epidemic in Asia, there has been growing concern in recent years about the HIV/AIDS risks with the steady rate of Asian and Pacific Islander (AAPI) migration to the United States. Little is known, however, about existing HIV risks among non-MSM (men who have sex with men) AAPIs. The purpose of this study was to examine self-reported HIV testing behaviors and their correlates among a sample of 604 Southeast Asians living in a U.S. urban setting. The HIV testing rate among our sample adults is 30.8%, lower than the median HIV testing rate in the U.S. adult population by state, lower than that of the general adult testing rate in the study city, and lower than that of the AAPI MSM population. A low sexually transmitted infection (STI) testing rate as a proxy for low perceived sexual risks and a dearth of HIV knowledge were associated with the low HIV testing rate. Traditional health care access measures, such as availability of medical insurance and a personal doctor, cannot explain the low HIV testing rate in this predominantly immigrant population. Culturally and linguistically appropriate HIV prevention campaigns could increase the awareness of HIV/STI risk in this AAPI population.  相似文献   
379.
BACKGROUND: The burden of inadequately controlled pediatric asthma on education and other daily activities is not well described. OBJECTIVE: To evaluate asthma-related activity limitations and productivity losses among children and caregivers. METHODS: Surveys were mailed to caregivers of children with asthma. Caregivers provided demographics, health-related quality of life (HRQL), workplace productivity, and asthma-related costs. Adolescents (aged 12-18 years) provided HRQL, asthma control, and school-based productivity, and young children (aged 4-11 years) completed an asthma control questionnaire with help from a caregiver. RESULTS: Among the 239 respondents, the mean age was 10.1 years; 49% were girls. More than half were inadequately controlled as measured using the Asthma Control Test. Both HRQL and productivity were significantly lower in patients with inadequately controlled asthma compared with those with controlled asthma. In the previous year, caregivers reported missing 1.4 days of work due to their child's asthma, with the child missing an average of 4.1 school days. Fewer adolescents with controlled asthma reported missing 1 or more school days in the previous week compared with adolescents with inadequately controlled asthma (3.5% vs 34.0%; P < .001). There were similar differences in caregiver workdays missed and health care resource use: both were significantly higher in children with inadequately controlled asthma. CONCLUSIONS: Inadequately controlled asthma has a significant impact on asthma-specific HRQL, school productivity and attendance, and work productivity of children and their caregivers.  相似文献   
380.
The objective of this study was to investigate the contribution of the interaction between CD40 and its ligand (CD40L) to antigen-induced airways inflammatory responses. To this end, we used a model involving ovalbumin (OVA) sensitization followed by OVA aerosol challenge in CD40L knockout (KO) mice. OVA-specific IgE and IgG1 were detected in the serum of the sensitized control, but not in CD40L-KO mice. After antigen challenge, sensitized control mice developed airway inflammation that was primarily eosinophilic. This inflammatory response was dramatically reduced in CD40L-KO mice. In contrast, similar numbers of eosinophils were observed in both the bone marrow and the peripheral blood in the sensitized controls and mutant strains after antigen challenge. To investigate the mechanisms underlying these findings, we examined levels of the cytokines IL-5, IL-4, and TNFalpha in both bronchoalveolar lavage (BAL) and serum. Similar levels of IL-5 were detected in BAL and serum of control and CD40L-KO mice; however, negligible levels of IL-4 in BAL and serum and of TNFalpha in BAL were detected in CD40L-KO mice when compared with control mice. Furthermore, we demonstrated that endothelial cell expression of vascular cell adhesion molecule 1 in OVA-sensitized and -challenged CD40L-KO mice was, as detected by immunohistochemistry, markedly decreased compared with that observed in similarly treated control mice. In addition, we locally overexpressed IL-4 and TNFalpha by using an adenoviral (Ad)-mediated gene transfer approach. Intranasal administration of either Ad/TNFalpha or Ad/IL-4 into OVA-sensitized and -challenged CD40L-KO mice did not reconstitute airway eosinophilia. However, concurrent administration of Ad/TNFalpha and Ad/IL-4 upregulated endothelial expression of vascular cell adhesion molecule 1, and resulted in full reconstitution of the inflammatory response in the airways. Together, these findings demonstrate the importance of the CD40-CD40L costimulatory pathway in the full expression of the inflammatory response in the airways.  相似文献   
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