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101.
The postural adaptation impairments of patients with Parkinson's disease (PD) suggest that the basal ganglia may be important for quickly modifying muscle activation patterns when the direction of perturbation or stance conditions suddenly change. It is unknown whether their particular instability to backward postural perturbations is due to specific abnormalities of parkinsonian postural muscle synergies in that direction and not present in other directions. In the present study, we test this hypothesis by comparing the patterns of leg and trunk muscle activation in 13 subjects with PD and 13 control subjects in response to eight randomly presented directions of horizontal surface translations while standing with either narrow or wide stance. The direction of maximum activation for each muscle was similar for PD and control subjects, suggesting that the basal ganglia is not critical for programming externally triggered postural synergies. However, antagonist muscle activation was earlier and larger in PD than in control subjects, resulting in coactivation. PD subjects also did not increase the magnitude of muscle activation as much as did control subjects when changing from wide to narrow stance. These results are consistent with the hypothesis that PD results in an inability to shape the pattern and magnitude of postural muscle responses for changes in perturbation direction and in stance position.  相似文献   
102.
CD1d-restricted NKT cells are a novel T cell lineage with unusual features. They co-express some NK cell receptors and recognize glycolipid antigens through an invariant T cell receptor (TCR) in the context of CD1d molecules. Upon activation through the TCR, NKT cells produce large amounts of IFN-gamma and IL-4. It has been proposed that rapid cytokine output by activated NKT cells may induce bystander activation of other lymphoid lineages. The impact of CD1d-restricted NKT cell activation in the induction of B cell-mediated immune responses to infection is still unclear. We show here that CD1-restricted NKT cells contribute to malarial splenomegaly associated with expansion of the splenic B cell pool and enhance parasite-specific antibody formation in response to Plasmodium berghei infection. The increased B cell-mediated response correlates with the ability of NKT cells to promote Th2 immune responses. Additionally, antibody responses against the glycosylphosphatidylinositol (GPI)-anchored protein merozoite surface protein 1 (MSP-1) were found to be significantly lower in CD1(-/-) mice compared to wild-type animals. P. berghei-infected MHC class II (MHCII)(-/-) mice also generated antibodies against MSP-1, suggesting that antibody production against GPI-anchored antigens in response to malaria infection can arise from both MHCII-dependent and independent pathways.  相似文献   
103.
Dysbindin gene (DTNBP1) has been associated with schizophrenia, but literature findings are inconsistent, and further analyses are required. This study is aimed to investigate if a set of DTNBP1 variations might influence clinic psychotic phenotype or treatment response in a sample of 240 Korean schizophrenic in-patients. Four variants have been selected (rs3213207; rs1011313; rs16876759; rs2619522) on the basis of previous findings of association with schizophrenia, bipolar disorder and antidepressant response. Single marker analysis gave marginal results. Haplotype analysis identified a significant association between A–A (rs3213207(A/G), rs1011313(A/G)) haplotype and lower PANSS total and positive scores at baseline (p = 0.01; 0.02) and at discharge (p = 0.008; 0.005). Covariate analysis revealed a more stable significant association between A–A haplotype and baseline scores. These results suggest a protective effect of A–A haplotype on psychotic positive symptoms at baseline.  相似文献   
104.
Aerosolized solutions of histamine or ovalbumin were administered to control or ovalbumin-sensitized guinea-pigs. The time to onset of respiratory distress (preconvulsion time) during challenge with these agents was measured using a force-displacement transducer on the animal's back. The preconvulsion time for each guinea-pig was compared with and without ketotifen pretreatment. Ketotifen administered both by aerosol and intraperitoneal injection (i.p.) significantly protected (p<0.001) each guinea-pig from the effects of aerosol challenge with histamine. Ovalbumin-sensitized animals were also protected from the effects of antigen aerosol challenge by ketotifen pretreatment. Sodium cromoglycate (DSCG), administered as an aerosol, did not protect sensitized animals from ovalbumin challenge. The Konzett-Rössler technique was used to measure the response to the intravenous injection (i.v.) of histamine in anaesthetized artificially ventilated guinea-pigs. Ketotifen was three times more potent than mepyramine in inhibiting the histamine-induced increase in air overflow volume.  相似文献   
105.
In an attempt to recognize early stages of focal segmental glomerulosclerosis (FSGS) in patients with a clinical course suggesting a diagnosis other than minimal change disease (MCD) and normal histology, or minor, nondiagnostic changes on light microscopy (LM), we used a protocol for systematic and extensive electron microscopy (EM) examination of kidney biopsies obtained from such patients. By this method ultrastructural pathology was found in 8 patients. These changes were localized, involving only portions of single glomerular segments. The findings included mild to moderate increase of the mesangial matrix, focal wrinkling of the capillary basement membrane, and early obliteration of the normal architecture of individual capillary loops, as well as electron-dense deposits in a mesangial and subendothelial distribution. Of these 8 patients, 2 are at present in remission without therapy (in 1, following therapy with cyclophosphamide); 3 are in remission on steroid therapy; 1 developed massive proteinuria during pregnancy, after a spontaneous remission lasting almost 2 years; 1 patient advanced to terminal renal failure 3 1/2 years after biopsy; and 1 died of sepsis 1 month after biopsy. We believe that the ultrastructural changes found may represent early or mild FSGS and that the protocol described can add valuable information in clinically worrisome patients in whom renal histology appears normal.  相似文献   
106.
BACKGROUND/OBJECTIVESIncreasing the consumption of vegetables and fruits in Mexico remains a challenge. Promoting sustainable food production systems through schools may be an effective way to educate young people about food and nutrition issues. A study of nutritional education in adolescents, based on the school garden, is necessary in order to evaluate its effects on the consumption of fruits and vegetables among middle- and upper-income segments of the population. The objective of this study was to evaluate the effect of an educational intervention, accompanied by a school garden as an educational teaching tool, to improve vegetable and fruit consumption by Mexican teenagers attending a private middle/high school.SUBJECTS/METHODSTeenagers between 12 and 18 years of age (n = 126) attending a private middle/high school in Queretaro, Mexico participated in a 3-arm, controlled, comparative impact study using a vegetable and fruit consumption frequency questionnaire, food consumption diaries, a psychosocial factor assessment questionnaire of vegetable and fruit consumption, and structured interviews. The participants were randomized into 3 experimental groups: 1) food education + school garden (FE + SG), 2) FE only, and 3) control group (CG).RESULTSThe FE + SG and FE groups significantly increased the frequency and daily intake of vegetables and fruits compared to the CG. The FE + SG group showed greater understanding of, reflection upon, and analysis of the information they received about vegetable and fruit consumption, as well as a greater willingness to include these in their daily diet.CONCLUSIONSFE accompanied by a SG as a teaching tool is more effective at promoting vegetable and fruit consumption than either education alone or control in teenagers in middle-upper income segments of the population.  相似文献   
107.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Um die Ausbreitung von SARS-CoV‑2 (schweres akutes Atemwegssyndrom-Coronavirus-Typ&nbsp;2) zu verlangsamen, haben Bund...  相似文献   
108.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Alkohol ist in Deutschland im Jugendalter die populärste Droge. Alkoholpräventionsprogramme, die im Setting Schule...  相似文献   
109.
110.
Background

Cardiovascular disease (CVD) risks are of concern among immigrants and refugees settling in affluent host countries. The prevalence of CVD and risk factors among Somali African immigrants to the U.S. has not been systematically studied.

Methods

In 2015–2016, we surveyed 1156 adult Somalis in a Midwestern metropolitan area using respondent-driven sampling to obtain anthropometric, interview, and laboratory data about CVD and associated risk factors, demographics, and social factors.

Results

The prevalence of diabetes and low physical activity among men and women was high. Overweight, obesity, and dyslipidemia were also particularly prevalent. Levels of calculated CVD risk across the community were greater for men than women.

Conclusion

Though CVD risk is lower among Somalis than the general U.S. population, our results suggest significant prevalence of risk factors among Somali immigrants. Comparison with prior research suggests that CVD risks may be increasing, necessitating thoughtful intervention to prevent adverse population outcomes.

  相似文献   
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