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31.
Metabolic Brain Disease - Parkinson’s disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta. The conventional therapeutic...  相似文献   
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Archives of Sexual Behavior - We compared gender dysphoria (GD) patients and their same-sex siblings in terms of their 2D:4D ratios, which may reflect prenatal exposure to androgen, one of the...  相似文献   
35.
Electromagnetic radiation (EMR) is emitted from electromagnetic fields that surround power lines, household appliances and mobile phones. Research has shown that there are connections between EMR exposure and cancer and also that exposure to EMR may result in structural damage to neurons. In a study by Salford et al. (Environ Health Perspect 111:881–883, 2003) the authors demonstrated the presence of strongly stained areas in the brains of rats that were exposed to mobile phone EMR. These darker neurons were particularly prevalent in the hippocampal area of the brain. The aim of our study was to further investigate the effects of EMR. Since the hippocampus is involved in learning and memory and emotional states, we hypothesised that EMR will have a negative impact on the subject’s mood and ability to learn. We subsequently performed behavioural, histological and biochemical tests on exposed and unexposed male and female rats to determine the effects of EMR on learning and memory, emotional states and corticosterone levels. We found no significant differences in the spatial memory test, and morphological assessment of the brain also yielded non-significant differences between the groups. However, in some exposed animals there were decreased locomotor activity, increased grooming and a tendency of increased basal corticosterone levels. These findings suggested that EMR exposure may lead to abnormal brain functioning.  相似文献   
36.

Background

Dental caries is still the most prevalent chronic disease worldwide. In the occupied Palestinian territory, data about oral health status and its determinants are scarce. This study aimed to assess the prevalence of dental caries and associated factors among schoolchildren in a random sample of marginalised schools in the West Bank.

Methods

Marginalised schools (according to the School Support Program [SPP] criteria) were stratified by district, gender, and grade level to select a random sample of 20 schools. Students in the sixth and ninth grades were interviewed by senior dental students about their oral hygiene and diet habits. Students' weight, height, gingival health, and dental caries experience were assessed. Senior dental students were trained and calibrated to carry out the interviews and the examinations. Parental informed consents were collected by school administrative staff. Ethics approval for the study was obtained from the Al-Quds University Scientific Research Ethics Committee.

Findings

In total, 1282 students completed the interviews and the clinical screening. The mean decayed, missing and filled teeth (DMFT) index was 6·4 (SD 4·4). According to the WHO dental caries experience classification, 49% (309 of 623) of the sixth grade students and 74% (484 of 658) of the ninth grade students fell in the high and very high categories. The mother's level of education and recent visit to the dentist correlated negatively with DMFT score (ρ=–0·06, p=0·029; ρ=–0·063, p=0·024). BMI was correlated positively with DMFT (r=0·092, p=0·001). Drinking milk and fresh juices was related to lower DMFT scores (r=–0·077, p=0·006 and r=–0·072, p=0·010). In the final model, grade (β=0·314, p<0·0001), gender (β=0·058, p=0·034), recent visit to the dentist (β=–0·059, p=0·029) and drinking fresh juices (β=–0·054, p=0·047) were significant factors in explaining the high level of dental caries in this sample.

Interpretation

Students in the marginalised schools of the West Bank have high DMFT scores that indicate high prevalence of dental caries. Access to dental care and bad oral health habits are associated with high disease prevalence. Interventions to improve access to care and increase awareness about healthy diet and hygiene habits are crucial to alleviate the burden of oral disease in this population.

Funding

AMIDEAST School Support Program (SSP).  相似文献   
37.
Erythropoietic activity is known to be closely associated with marrow iron uptake. A modification of the standard measure of plasma iron turnover has been developed in which erythron transferrin uptake (ETU) rather than iron uptake has been calculated. The ETU has the advantage of providing a parameter of erythroid marrow activity independent of change produced by plasma iron and transferrin saturation. Measurements in 80 patients with anemia were compared to the normal value of 60 +/- 12 mumol/L whole blood/d. The mean ETU for ten patients with severe aplastic anemia and for six patients with pure red-cell aplasia were 12 +/- 8 and 12 +/- 11 mumol/L whole blood/d, respectively. In ten transfusion-dependent patients with renal failure under dialysis therapy, the mean value was 35 +/- 11, while ten other dialyzed patients who were transfusion independent had a mean ETU of 73 +/- 21 mumol/L whole blood/d. Sixteen patients with hemolytic anemia had an average ETU of 400 +/- 130, while 28 patients with ineffective erythropoiesis had a mean value of 474 +/- 147 mumol/L whole blood/d. While patients with hypoproliferative anemia showed no relation between the severity of anemia and ETU, those with hyperproliferative erythroid marrow showed increasing values as the anemia became more severe. Sequential measurements in patients with aplastic anemia under treatment and in thalassemic patients under transfusion therapy showed the value of this measurement in monitoring the effects of treatment on erythroid marrow activity. It is concluded that the measurement of ETU provides a more direct ferrokinetic evaluation of erythroid activity in anemic states.  相似文献   
38.
Identification of T lymphocytes in human mixed hemopoietic colonies   总被引:11,自引:0,他引:11  
Messner  HA; Izaquirre  CA; Jamal  N 《Blood》1981,58(2):402-405
The addition of a T-cell growth-promoting medium (PHA-TCM) to culture conditions that support growth of multi-lineage hemopoietic colonies enhances the proliferation of cells with lymphoid morphology within these colonies. These cells were identified as T lymphocytes by their ability to form rosettes with SRBC and their reaction with monoclonal antibodies (OKT3, OKT4) directed against T-cell-specific surface components. They continue to proliferate extensively under the influence of PHA-TCM after transfer of mixed colonies into liquid suspension culture. Supportive evidence for a common progenitor of myeloid and lymphoid cells within single mixed colonies is provided by Y-chromatin body analysis of E-rosette positive and negative cells in colonies grown in cocultures of male and female bone marrow cells.  相似文献   
39.
Horne  MK d; Rosse  WF; Flickinger  EG; Saltzman  HA 《Blood》1975,45(3):365-375
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress.  相似文献   
40.
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