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1.
Nutritional status and metabolic fuels are factors involved in the regulation of GH secretion and GH responses to GHRH. The effects of feeding on GHRH-induced GH release were studied in 13 normal women, 14 obese women, and 9 women with anorexia nervosa. GHRH-(1-44) (50 micrograms, iv) was administered at 0900 h after an overnight fast or at 1300 h after a normal meal at 0800 h, and at the same times 45 min after a 800-Cal meal on different days. The mean peak plasma GH responses to GHRH administered before a meal at 0900 h were 52.8 +/- 5.6 (+/- SE) micrograms/L in normal women, 8.2 +/- 1.3 micrograms/L in obese women, and 53.2 +/- 7.7 micrograms/L in anorexic women. When GHRH was administered before a meal at 1300 h, the mean peak plasma GH levels were lower than those at 0900 h; this reduction was -64.2% in normal women, -64.9% in obese women, and -55.8% in women with anorexia nervosa. After feeding, the plasma GH responses to GHRH were blunted in normal women at 0900 h (-60.9%) and 1300 h (-34.6%) compared with the fasting peak responses. In obese women the plasma GH response to GHRH after feeding was increased compared with that when these women had fasted (+60% at 0900 h and +406.9% at 1300 h). Finally, differential effects of feeding were present in anorexic women; the response was lower at 0900 h (-46.4%) and greater at 1300 h (+50.8%). We conclude that there is an ultradian variation in GHRH-stimulated GH secretion and that the responses differ according to nutritional status and body weight.  相似文献   
2.
Following the demonstration of a positive prolactin (PRL) response to growth hormone-releasing hormone (GHRH) in acromegalic and anorexic women, we have injected GHRH (50 micrograms intravenously as a bolus) in normal women during various phases of their menstrual cycle in order to establish whether a positive response was present also in normal subjects. Synthetic GHRH 1-44 elicited a significant increase in circulating PRL levels in eight women studied during the periovulatory phase of the menstrual cycle. In contrast, no significant changes in circulating PRL levels after GHRH administration were found in nine women during the midfollicular phase or in five women during the midluteal phase. A temporal correlation between the midcycle gonadotropin peak and the positive response to GHRH has been observed. Synthetic GHRH elicited the expected increase in GH levels during all phases of the cycle studied. Our data demonstrate that GHRH is capable of stimulating a PRL response in normal subjects and raise the possibility that PRL secretion is regulated by several hormones of hypothalamic origin.  相似文献   
3.
A prerequisite to dephosphorylation at Ser–Pro or Thr–Pro motifs is the isomerization of the imidic peptide bond preceding the proline. The peptidyl-prolyl cis/trans isomerase named Pin1 catalyzes this mechanism. Through isomerization, Pin1 regulates the function of a growing number of targets including the microtubule-associated tau protein and is supposed to be deregulated Alzheimer's disease (AD). Using proteomics, we showed that Pin1 is posttranslationally modified on more than 5 residues, comprising phosphorylation, N-acetylation, and oxidation. Although Pin1 expression remained constant, Pin1 posttranslational two-dimensional pattern was modified by tau overexpression in a tau-inducible neuroblastoma cell line, in our THY-Tau22 mouse model of tauopathy as well as in AD. Interestingly, in all of these systems, Pin1 modifications were very similar. In AD brain tissue when compared with control, Pin1 is hyperphosphorylated at serine 16 and found in the most insoluble hyperphosphorylated tau fraction of AD brain tissue. Furthermore, in all tau pathology conditions, acetylation of Pin1 may also contribute to the differences observed. In conclusion, Pin1 displays several posttranslational modifications, which are specific in tauopathies and may be useful as biomarker.  相似文献   
4.
The study tested whether nociceptive stimuli applied to a body limb can orient spatial attention in external space toward visual stimuli delivered close to that limb. Nociceptive stimuli were applied to either the left or the right hand. Task‐relevant visual stimuli were delivered at the location adjacent to the stimulated hand (70% valid trials) or adjacent to the other hand (30% invalid trials). Visual stimuli were discriminated with shorter reaction times and elicited ERPs of greater magnitude in the valid as compared to the invalid trials. This enhancement affected the N1 component, suggesting that the location of the nociceptive cue modifies visual processing through a modulation of neural activity in the visual cortex. We hypothesize the existence of a common frame of reference able to coordinate the mapping of the space of the body and the mapping of the external space.  相似文献   
5.
Abstract. An average of six annual rounds of ivermectin and albendazole were distributed in Plateau and Nasarawa States, Nigeria, to eliminate lymphatic filariasis. From 2007 to 2008, population-based surveys were implemented in all 30 local government areas (LGAs) of the two states to determine the prevalence of Wuchereria bancrofti antigenemia to assess which LGA mass drug administration (MDA) could be halted. In total, 36,681 persons from 7,819 households were examined for filarial antigen as determined by immunochromatographic card tests. Overall antigen prevalence was 3.05% (exact upper 95% confidence interval [CI] = 3.41%) with an upper 95% CI range by LGA of 0.50-19.3%. Among 3,233 children 6-7 years of age, overall antigen prevalence was 1.71% (exact upper 95% CI = 2.19%), too high to recommend generally halting MDA in the two-state area. However, based on criteria of < 2% antigenemia among persons > 2 years of age, stopping MDA was recommended for 10 LGAs.  相似文献   
6.

Background

This study focused on the 47 Member States of the World Health Organization (WHO) African Region. The specific objectives were to prepare a synthesis on the situation of health systems components, to analyse the correlation between the interventions related to the health Millennium Development Goals (MDGs) and some health systems components and to provide overview of four major thrusts for progress towards universal health coverage (UHC).

Methods

The WHO health systems framework and the health-related MDGs were the frame of reference. The data for selected indicators were obtained from the WHO World Health Statistics 2014 and the Global Health Observatory.

Results

African Regions average densities of physicians, nursing and midwifery personnel, dentistry personnel, pharmaceutical personnel, and psychiatrists of 2.6, 12, 0.5, 0.9 and 0.05 per 10 000 population were about five-fold, two-fold, five-fold, five-fold and six-fold lower than global averages.Fifty-six percent of the reporting countries had fewer than 11 health posts per 100 000 population, 88% had fewer than 11 health centres per 100 000 population, 82% had fewer than one district hospital per 100 000 population, 74% had fewer than 0.2 provincial hospitals per 100 000 population, and 79% had fewer than 0.2 tertiary hospitals per 100 000 population.Some 83% of the countries had less than one MRI per one million people and 95% had fewer than one radiotherapy unit per million population. Forty-six percent of the countries had not adopted the recommendation of the International Taskforce on Innovative Financing to spend at least US$ 44 per person per year on health. Some of these gaps in health system components were found to be correlated to coverage gaps in interventions for maternal health (MDG 5), child health (MDG 4) and HIV/AIDS, TB and malaria (MDG 6).

Conclusions

Substantial gaps exist in health systems and access to MDG-related health interventions. It is imperative that countries adopt the 2014 Luanda Commitment on UHC in Africa as their long-term vision and back it with sound policies and plans with clearly engrained road maps for strengthening national health systems and addressing the social determinants of health.
  相似文献   
7.
Data Envelopment Analysis has been widely used to analyze the efficiency of health sector in developed countries, since 1978, while in Africa, only a few studies have attempted to apply DEA in the health organizations. In this paper we measure technical efficiency of public health centers in Kenya. Our finding suggests that 44% of public health centers are inefficient. Therefore, the objectives of this study are: to determine the degree of technical efficiency of individual primary health care facilities in Kenya; to recommend the performance targets for inefficient facilities; to estimate the magnitudes of excess inputs; and to recommend what should be done with those excess inputs. The authors believe that this kind of studies should be undertaken in the other countries in the World Health Organization (WHO) African Region with a view to empowering Ministries of Health to play their stewardship role more effectively.  相似文献   
8.
Neuronal death is a process which may be either physiological or pathological. Apoptosis and necrosis are two of these processes which are particularly studied. However, in neurodegenerative disorders, some neurons escape to these types of death and "agonize" in a process referred to as neurofibrillary degeneration. Neurofibrillary degeneration is characterized by the intraneuronal aggregation of abnormally phosphorylated microtubule-associated Tau proteins. A number of studies have reported a reactivation of the cell cycle in the neurofibrillary degeneration process. This reactivation of the cell cycle is reminiscent of the initiation of apoptosis in post-mitotic cells where G1/S markers including cyclin D1 and cdk4/6, are commonly found. However, in neurons exhibiting neurofibrillary degeneration, both G1/S and G2/M markers are found suggesting that they do not follow the classical apoptosis and an aberrant cell cycle occurs. This aberrant response leading to neurofibrillary degeneration may be triggered by the sequential combination of three partners: the complex Cdk5/p25 induces both apoptosis and the "abnormal mitotic Tau phosphorylation". These mitotic epitopes may allow for the nuclear depletion of Pin1. This latter may be responsible for escaping classical apoptosis in a subset of neurons. Since neurofibrillary degeneration is likely to be a third way to die, molecular mechanisms leading to changes in Tau phosphorylation including activation of kinases such as cdk5 or other regulators such as Pin1 could be important drug targets as they are possibly involved in early stages of neurodegeneration.  相似文献   
9.
The Strong Heart Study (SHS) is a large, multi-community study to investigate the high incidence of cardiovascular disease (CVD) among American Indians and to improve long-term health outcomes within the communities. CVD is the No. 1 cause of death for three geographically and culturally diverse American Indian populations. The SHS investigated the prevalence and incidence of CVD as well as the distribution of risk factors in members of 13 American Indian tribes in Oklahoma, Arizona, and (as one region) North and South Dakota. The SHS enrolled more than 4500 participants ranging in age from 45 to 74 years. During the three-phase study, which began with baseline examinations from 1989 through 1991 and concluded in 1999, participants received medical examinations in each phase. To build trust and cooperation, SHS investigators worked closely with tribal leaders and community members, including establishing empowered committees and hiring community members for jobs within the study. As a result of such cooperation, the SHS maintained retention rates of about 90% across all three phases. Benefits to tribal communities also included health care improvements and education for healthy lifestyles. The SHS could serve as a model for similar studies of American Indians or other minority groups.  相似文献   
10.
On May,24 1994, the then South African president, Mr. Nelson Mandela, declared that all health care for children under the age of 6 years, and pregnant women would be free. Unfortunately, there has been no significant decrease in maternal, perinatal and infant mortality. Thus, there is a need of research into the factors that influence the demand for antenatal services. The objectives of this paper are to (a) establish the determinants of individual pregnant women's choice to seek antenatal care; and (b) deal with potential endogeneity bias in the relationship between the decision to seek pre-natal care and perceived health status. The joint determination of consumption of antenatal care and pregnant woman's health status requires estimation of a simultaneous system. To help mitigate the simultaneity bias and avoid the inconsistency inherent in the application of Ordinary least Squares (OLS) method to simultaneous equations systems, we used Two-Stage Probit Maximum Likelihood Estimator Method. In the antenatal structural-form equation, the coefficients for TOILET, AGE, OCCUPATION, EMPLOYMENT, SMOKER, METHODS and QUALITY were statistically significant at P 相似文献   
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