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151.
BACKGROUND: There has thus far been no empirical research on the occurrence of antenatal psychiatric morbidity in Chinese population. Epidemiological studies in western societies generally show that depressive episodes occur in 10-20% of pregnant women. Longitudinal studies have demonstrated that antenatal depression is one of the most powerful predictors of postnatal depression. There is also a growing literature that shows that antenatal psychological distress can adversely affect maternal and foetal well being. METHODS: At 38 weeks of pregnancy, 238 consecutive women were invited to return for psychiatric assessment. The participants were interviewed using the non-patient version of the Structured Clinical Interview for DSM-IV (SCID-NP). RESULTS: Seventy women (29%) declined to participate, and another 11 (5%) defaulted the SCID interview. Among the 157 women interviewed, the 1-month prevalence of antenatal depression was 4.4%. The 1-month prevalence of all psychiatric diagnoses was 6.4%. The prevalence of antenatal depression and all psychiatric diagnoses for the entire pregnancy was 6.4% and 8.3%, respectively. LIMITATIONS: About a third of eligible subjects did not participate in the study. CONCLUSIONS: A significant proportion of Chinese women suffer from psychiatric morbidity during pregnancy. Depressive disorders are by far the commonest morbidity in the study population. Given the scope of the morbidity and the potential impact on obstetric and neonatal outcomes, early screening and treatment are warranted.  相似文献   
152.
D Strickland  U R Kees    P G Holt 《Immunology》1996,87(2):250-258
Alveolar macrophages (AM) are recognized as archetypal 'activated' macrophages with respect to their capacity to suppress T-cell responses to antigen or mitogen, and this function has been ascribed an important role in the maintenance of local immunological homeostasis at the delicate blood:air interface. The present study demonstrates that this suppression involves a unique form of T-cell anergy, in which 'AM-suppressed' T cells proceed normally through virtually all phases of the activation sequence including Ca2+ flux, T-cell receptor (TCR) modulation, cytokine [including interleukin-2 (IL-2)] secretion and IL-2 receptor (IL-2R) expression. However, the 'suppressed' T cells fail to up-regulate CD2, and do not re-express normal levels of TCR-associated molecules after initial down-modulation; moreover, they are unable to transduce IL-2 signals leading to phosphorylation of IL-2R-associated proteins, and remained locked in G0/G1. The induction of this form of anergy is blocked by an NO-synthase inhibitor, and is reversible upon removal of AM from the T cells, which then proliferate in the absence of further stimulation. We hypothesize that this mechanism provides the means to limit the magnitude of local immune responses in this fragile tissue microenvironment, while preserving the capacity for generation of immunological memory against locally encountered antigens via clonal expansion of activated T cells after their subsequent migration to regional lymphoid organs. In an accompanying paper, we demonstrate that a significant proportion of T cells freshly isolated from lung exhibit a comparable surface phenotype.  相似文献   
153.
Individuals living in regions where malaria is endemic develop an acquired immunity to malaria which enables them to remain asymptomatic while still carrying parasites. Field studies indicate that cumulative exposure to a variety of diverse Plasmodium parasites is required for the transition from symptomatic to asymptomatic malaria. This study used a simulation model of the within-host dynamics of P. falciparum to investigate the development of acquired clinical immunity under different transmission conditions and levels of parasite diversity. Antibodies developed to P. falciparum erythrocyte membrane protein 1 (PfEMP1), a clonally variant molecule, were assumed to be a key human immunological response to P. falciparum infection, along with responses to clonally conserved but polymorphic antigens. The time to the development of clinical immunity was found to be proportional to parasite diversity and inversely proportional to transmission intensity. The effect of early termination of symptomatic infections by chemotherapy was investigated and found not to inhibit the host's ability to develop acquired immunity. However, the time required to achieve this state was approximately double that compared to when no treatment was administered. This study demonstrates that an immune response primarily targeted against PfEMP1 has the ability to reduce clinical symptoms of infections irrespective of whether treatment is administered, supporting its role in the development of acquired clinical immunity. The results also illustrate a novel use for simulation models of P. falciparum infections, investigation of the influence of intervention strategies on the development of naturally acquired clinical immunity.  相似文献   
154.
Associations among baseline physical activity, aerobic fitness, changes in physical activity, and 7-y changes in adiposity were determined. The sample consisted of 602 males and 644 females, aged 20-69 y, from the 1981 Canada Fitness Survey and the 1988 Campbell's Survey. Questionnaire-derived measures of physical activity level consisted of activity energy expenditure (AEE) and time spent on physical activity. Participants were grouped into physical activity level categories by AEE and physical activity intensity (based on MET values), and physical activity level changes were determined from movement between tertiles of AEE from baseline to follow-up. Aerobic fitness levels at baseline were determined using the Canadian Aerobic Fitness Test. Changes in body mass, the sum of five skinfolds (SF5), and waist circumference (WC) were used as indicators of adiposity change. ANCOVA and multiple regression analyses indicated that neither baseline physical activity levels, intensity, physical activity change categories, nor aerobic fitness levels were significant predictors of changes in adiposity. In conclusion, physical activity was not predictive of 7-y changes in indicators of adiposity in this sample.  相似文献   
155.
In our sample of 15 hospitalized patients with severe psychotic depression, six responded to therapy with tricyclic antidepressants combined with neuroleptics. Of the nine nonresponders, eight showed an excellent clinical response to electroconvulsive therapy (ECT). The clinical outcome after 6 months of treatment was similar in both groups. We recommend that protracted, complicated trials of pharmacotherapy be reevaluated in psychotic depression. A prospective comparative study of ECT and pharmacotherapy is needed to define the optimal treatment for psychotic depression.  相似文献   
156.
Enhanced pancreatic and skin tumorigenesis in cabbage-fed hamsters and mice   总被引:1,自引:0,他引:1  
Studies were conduded to evaluate the ability of dietary driedcabbage supplements to inhibit pancreatic carcinogenesis inhamsters and skin tumorigenesis in mice. Pancreatic cancer wasinduced by treatment with 40 mg/kg body wt N-nitrosobis-(2oxopropyl)amine(BOP). Cabbage was fed from before carcinogen treatment in lowfat diet and, beginning 1 week after BOP treatment, cabbagewas given in low fat and high fat diets in comparison with therespective non-cabbage containing diets. Dried cabbage was incorporatedat 9 and 11% levels into the low and high fat diets. Feedingcabbage in the high fat diet elevated the yield of BOP-inducedpancreatic ductular cardnoma (1.6 carcinomas/effedive animal)in comparison with that observed in hamsters fed cabbage ina low fat diet or in those given a high fat diet without cabbage, 0.6–0.8 carcinomaa/effedive animal (P 0.05). Furthermore,the incidence of BOP-induced gall bladder adenocadnomm was elevatedin cabbage-fed hamsters irrespedve of dietary fat intake. Effetsof dietary fat and cabbage on food consumption, body weight,and serum T3 and T4 values are described. Skin tumorigenesiswas induced in SENCAR mice by 10 nmd 7,12 dlmethylbenz[a]anthracene(DMBA) and promoted beginning 1 week later with twice weeklyapplications of 2 µg 12-O-tetradecanoyl-13-phorbol acetate(TPA). Dried cabbage was incorporated into AIN semi-purifieddiets from before DMBA treatment and throughout TPA treatment.Skin papilloma yield was elevated in DMBA-initiated TPA-promotedmice that were fed diets containing 10% cabbage. Mice fed cabbagedeveloped an average of 8.45 papillomas per mouse following22 weeks of promotion while mice given control diet developed7.25 papillomas per mouse (P < 0.001). Cabbage feeding didnot influence survival, food consumption or body weight of themice. These results suggest the need for further research onthe use of cabbage as a chemopreventive measure.  相似文献   
157.
Many prospective biomedical studies collect longitudinal clinical and lifestyle data that are both continuous and discrete. In some studies, there is interest in the association between a binary outcome and the values of these longitudinal measurements at a specific time point. A common problem in these studies is inconsistency in timing of measurements and missing follow-ups which can lead to few measurements at the time of interest. Some methods have been developed to address this problem, but are only applicable to continuous measurements. To address this limitation, we propose a new class of joint models for a binary outcome and longitudinal explanatory variables of mixed types. The longitudinal model uses a latent normal random variable construction with regression splines to model time-dependent trends in mean with a Dirichlet Process prior assigned to random effects to relax distribution assumptions. We also standardize timing of the explanatory variables by relating the binary outcome to imputed longitudinal values at a set time point. The proposed model is evaluated through simulation studies and applied to data from a cancer survivor study of participants in the Women's Health Initiative.  相似文献   
158.
Medicine, Health Care and Philosophy - Beauchamp and Childress’ biomedical principlism is nearly synonymous with medical ethics for most clinicians. Their four principles are theoretically...  相似文献   
159.
160.
Complementary feeding (CF) is an important determinant of early and later life nutrition with great implications for the health status and the development of an adequate growth. Parents can choose between homemade foods (HMFs) and/or commercial infant foods (CIFs). There is no consistent evidence as to whether HMFs provide a better nutritional profile and variety over CIFs. The aim of this study was to compare the nutritional profiles and food variety of HMFs versus CIFs in the Spanish market targeted for infants (6–11 months) and young children (12–18 months). Thirty mothers with their children aged 6 to 18 months were included in this cross-sectional study, following a 3-day weighed food diary of which HMFs were collected and chemically analyzed. HMFs meals for infant provided significantly lower energy, higher protein and higher fiber, for young children provided significantly higher protein and fiber than CIFs meals. HMFs fruit purees for infant shown significantly higher fiber and for young children provided higher energy than CIFs. HMFs meals contained a significantly greater number of different vegetables than CIFs meals (3.7 vs. 3.3), with carrot as the most frequently used in both. However, in CIFs fruit purees shown higher different fruits than HMFs, in both the banana was the fruit most frequently used. There was a predominance of meat and lack of oily fish and legumes in both HMFs and CIFs meals. HMFs and CIFs were equally characterized by a soft texture and yellow-orange colours. Importantly, our findings emphasize the need for clear guidelines for the preparation of HMFs as well as the promotion of food variety (taste and textures) in both HMFs and CIFs to suit infants’ and young children’s nutritional and developmental needs.  相似文献   
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