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41.
AV Osorio  US Alon 《Pediatrics》1997,100(4):675-681
OBJECTIVES: 1) To evaluate the relationships between urinary sodium (UNa), potassium (UK), and calcium (UCa) excretion in the pediatric population; and 2) to determine the effect of increasing potassium intake in patients with idiopathic hypercalciuria and investigate whether this intervention can be offered as another mode of therapy in this patient population. DESIGN: Prospectively, we determined UNa, UK, UCa, and creatinine (Cr) concentrations in randomly collected urine samples from children on initial evaluation for urinary frequency, dysuria, hematuria, enuresis, or kidney stones to identify children with hypercalciuria. SETTING: The outpatient renal clinic of an academic hospital. PARTICIPANTS: Twenty-three black children (13 girls and 10 boys) and 77 white children (44 girls and 33 boys) 3.92 to 16.67 years of age. INTERVENTIONS: Eleven children with hypercalciuria were given potassium supplementation or placed on a high-potassium diet for at least 2 weeks. OUTCOME MEASURES: UNa to UK, UNa to Cr, UK to Cr, and UCa to Cr ratios were calculated from measured levels of urinary minerals. These were repeated in 11 hypercalciuric patients after 2 weeks of increased potassium intake. RESULTS: A total of 100 urine samples were analyzed. The UCa/Cr ratio in blacks 0.04 +/- 0.06 (mean +/- standard deviation) was significantly lower than in whites 0.16 +/- 0.12. There were 21 hypercalciuric white children versus only 1 black child. Linear regression analysis revealed a positive direct correlation between UNa/Cr and UCa/Cr in all 100 subjects and in whites alone but not in blacks. An inverse relationship existed between UK/Cr and UCa/Cr in all subjects and in whites and showed a strong trend in blacks. A marked direct relationship was found between UNa/K and UCa/Cr in all subjects (r = .43) as well as in whites (r = .59) and blacks (r = .49). One black child and 10 white hypercalciuric children were treated with "extra" K for at least 2 weeks. The UNa/K decreased from 4.73 +/- 2.28 to 1.98 +/- 1.09, and the UCa/Cr decreased from 0. 31 +/- 0.10 to 0.14 +/- 0.07, with resolution or improvement of the patients' symptoms. CONCLUSIONS: In our patient population with urinary symptoms, the UCa/Cr ratio in black children is lower and hypercalciuria less common than in white children. In both white and black populations, the UNa/K ratio had the strongest association with the UCa/Cr ratio, indicating an opposing role of UNa and UK on the UCa/Cr ratio. Increased potassium intake was found to be beneficial for hypercalciuric children by decreasing the UNa/K ratio and, consequently, the UCa/Cr ratio.  相似文献   
42.
Social media is being used for recruitment and the study of health‐care choices and behavior, and could be particularly helpful to reach young adult populations outside of a 4 year college setting. The aim of this study was to report on overall success of recruiting young adults in diverse settings with respect to education and employment into a study using Facebook (FB). Young adults (n = 380, 50% male, 44% white) who had been involved in a longitudinal research project received a friend request from the research study group's profile. Acceptance rates of friend requests and sociodemographic and mental health factors associated with acceptance were evaluated. Approximately 67% of 318 participants who received a friend request accepted the request. Sociodemographic and mental health characteristics were similar between those who did and did not accept friend requests, suggesting non‐differential recruitment through FB. Friending through FB is a feasible way to reach young adults involved in health and behavioral research, and could be a way to expand the populations that are studied in health science research to maximize generalizability of the conclusions drawn.  相似文献   
43.
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.  相似文献   
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Labial adhesions are usually seen in early childhood or in the postmenopausal years, but this clinical entity is rarely seen in the reproductive years. We report a case of labial adhesion with acute urinary retention secondary to Bartholin's abscess in a reproductive‐aged woman with normal menstrual periods. We emphasize the possible occurrence of labial adhesion following Bartholin's abscess in the reproductive years with normal estrogen levels.  相似文献   
46.
Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
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47.
Prior studies have consistently found the occurrence of depression to be higher among persons with lower socio-economic status (SES), but causal mechanisms for this relationship are often not well understood. For example, while depression has been shown to increase during spells of unemployment, little work has been done on job attributes that may be related to depression among employed people early in their careers. This study links the 1992 wave of the National Longitudinal Survey of Youth 1979 cohort-which included Depression symptom scores on the Center for Epidemiologic Studies Depression (CES-D) instrument-to the US Department of Labor's new occupational characteristics O*Net dataset. The resulting dataset includes information regarding depression, SES, and specific attributes of jobs held by the young adult respondents. Job attributes included measures of social status, interpersonal stressors, and physical conditions. Multivariate analysis revealed that for young men, higher job status is associated with lower CES-D scores. Higher scores on the opposition scale, which measures the extent to which employees are obliged to take a position opposed to others, is associated with higher CES-D scores. For young women, physically uncomfortable or dangerous jobs are associated with more depressive symptoms. Results are stratified by race/ethnicity. For Black men, unlike for White men or Latinos, job security is associated with fewer depressive symptoms; and for Latino men, but not for Black or White men, physically uncomfortable or dangerous jobs are associated with more depressive symptoms. For Black women, job status is associated with fewer depressive symptoms. We conclude that part of the SES-depression relationship may arise from the psychosocial aspects of jobs, which we have found to be significantly and meaningfully associated with depressive symptoms among employed young adults.  相似文献   
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A prospective, longitudinal two-year study to determine the epidemiology of persistent ( 14 days'duration) diarrhea in rural children of Guatemala was undertaken. Three-hundred and twenty-one children aged 0-35 months were kept under surveillance by twice-a-week home visits. The overall incidence of diarrhea was 0.147 per child-week; the incidence of persistent diarrhea was 0.014 per child-week. The peak of persistent diarrhea was observed in infants below six months of age, with a continuous decline thereafter. This trend in incidence of persistent diarrhea was associated with a higher proportion (16%) of illnesses persisting for more than 13 days in children younger than six months of age as compared to children 30-35 months old (4%). Males had more diarrhea (0.156 per child-week) than females (0.139 per child week). Among children above 18 months of age, the proportion of episodes that lasted for more than 13 days was lower in females than in males.  相似文献   
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