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701.
Ghandour RM Overpeck MD Huang ZJ Kogan MD Scheidt PC 《Archives of pediatrics & adolescent medicine》2004,158(8):797-803
BACKGROUND: Data on the prevalence and co-occurrence of multiple somatic symptoms among US adolescent females as they are influenced by sociodemographic, behavioral, and environmental factors is limited. OBJECTIVES: To describe the health status of adolescent US females measured by the prevalence, frequency, and co-occurrence of headache, stomachache, backache, and morning fatigue and to investigate associations between selected risk and protective factors. DESIGN, SETTING, AND PARTICIPANTS: School-based, cross-sectional, nationally representative survey of adolescents in the 6th through 10th grades in the US. Data collected between 1997 and 1998. MAIN OUTCOME MEASURES: Prevalence of headache, stomachache, backache, and morning fatigue. RESULTS: Among US adolescent girls, 29.1% experience headaches, 20.7% report stomachaches, 23.6% experience back pain, and 30.6% report morning fatigue at the rate of more than once a week. Co-occurrence of somatic complaints is common. Among girls who experienced headaches more than once a week, 3.2 million (53.3%) also reported stomach pain more than once a week and 4.1 million (74.3%) reported morning fatigue more than once a week. Heavy alcohol use, high caffeine intake, and smoking cigarettes every day were strongly associated with all symptoms, while parent and teacher support served as protective factors. CONCLUSIONS: Somatic complaints of headache, stomachache, backache, and morning fatigue are common among US adolescent girls and co-occur often. Effective clinical treatment of this population requires comprehensive assessment of all female adolescents presenting with seemingly isolated somatic complaints. 相似文献
702.
RBC alloimmunization and autoimmunization among transfusion-dependent Arab thalassemia patients 总被引:3,自引:0,他引:3
Ameen R Al-Shemmari S Al-Humood S Chowdhury RI Al-Eyaadi O Al-Bashir A 《Transfusion》2003,43(11):1604-1610
BACKGROUND: Thalassemia major is a common hemoglobinopathy in the Arabian Gulf region. However, limited data are available on the frequency of RBC alloimmunization and autoimmunization in transfusion-dependent Arab thalassemia patients. STUDY DESIGN AND METHODS: A total of 190 thalassemia major patients were classified as Kuwaiti Arab and non-Kuwaiti Arab. Pretransfusion investigation records were reviewed for the presence of RBC alloantibody and autoantibody, and the age at which RBC alloantibody was developed. RESULTS: Fifty-seven (30%) patients developed RBC alloantibodies. The most common clinically significant alloantibodies were directed against antigens in the Kell and Rh systems. Anti-K developed in 41 (72%) patients followed by anti-E in 26 (45.6%). RBC autoantibodies developed in 21 (11%) patients with and without underlying RBC alloantibodies. Sixty-six (49.6%) RBC alloantibodies developed between the ages of 2 and 10 years. CONCLUSION: Several factors might have contributed to the high alloimmunization and autoimmunization rate observed in this study, including the heterogeneity of the population living in Kuwait, lack of better-matched donors for those patients, and the use of poststorage leukodepleted blood. It is recommended that thalassemia patients receive blood matched for Rh and Kell antigens and prestorage leukodepleted RBCs. 相似文献
703.
OBJECTIVE: To determine the prevalence of hypovitaminosis D in exclusively breast-feeding infants and their mothers in a community where maternal sunshine exposure is low. STUDY DESIGN: Serum levels of calcium, phosphate, alkaline phosphatase, 25-hydroxy vitamin D (25-OHD), and intact parathyroid hormone were measured in 90 unsupplemented healthy term breast-feeding Arab/South Asian infants and their mothers in summer. Maternal dietary vitamin D intake was also estimated. RESULTS: The median age of infants was 6 weeks. The median serum 25-OHD concentrations in mothers (8.6 ng/mL) and infants (4.6 ng/mL) were low, and 61% of the mothers and 82% of the 78 infants tested had hypovitaminosis D (serum 25-OHD <10 ng/mL). The infants with hypovitaminosis D had elevated serum alkaline phosphatase and a tendency to higher serum intact parathyroid hormone levels. The average daily maternal vitamin D intake from commercial milk was 88 IU. CONCLUSIONS: Hypovitaminosis D is common in summer in exclusively breast-feeding infants and their mothers. The results provide justification for vitamin D supplementation of breast-feeding infants and mothers in the United Arab Emirates. Low vitamin D intake probably contributed to low maternal vitamin D status. 相似文献
704.
Primary gastrointestinal lymphoma is the most common extranodal presentation of non-Hodgkin's lymphoma. In this retrospective study, all cases of primary gastrointestinal lymphoma registered at Kuwait Cancer Control Center between January 1992 and December 2001 were reviewed. Patients were diagnosed through an endoscopic biopsy or exploratory laparotomy. Staging procedures included computed axial tomography scan, bone marrow biopsy, barium and follow-through study, as well as routine chemistry (including lactate dehydrogenase) and hemography. There were 46 patients (30 men and 16 women); ages ranged from 16 to 82 years (median age, 43.6 years). The most common site of involvement was the stomach (70%), and the most common histology was large B cell. At least 50% of cases underwent primary radical surgery, and the majority of patients received subsequent chemotherapy and/or local radiation therapy. Chemotherapy consisted of the CHOP (cyclophosphamide/doxorubicin/vincristine/prednisone) regimen for large B-cell histology and CVP (cyclophosphamide/vincristine/prednisone) or oral alkylating agents for low-grade histology. Of this cohort, only 12 cases (26%) have had local or distant relapse. Disease-free survival rates for low-grade and high-grade non-Hodgkin's lymphoma were 64% and 81%, respectively. Primary gastrointestinal lymphoma is a potentially curable malignancy. 相似文献
705.
El Seweidy MM El-Swefy SE Abdallah FR Hashem RM 《The Journal of pharmacy and pharmacology》2005,57(11):1467-1474
The dietary balance of long-chain fatty acids may influence processes involving leukocyte endothelial interactions, such as atherogenesis and inflammation. The relationship between proatherogenic lipoproteins and chemotactic motility is still controversial. However, the interaction of the former can increase recruitment of monocytes to the vessel walls and accelerate the events of atherogenesis. The current study examined the effects of unsaturated fatty acid levels on the oxidative susceptibility of lipoprotein, chemokine expressions and their relationship to atherosclerotic lesion development in experimental rats. Male Wistar rats were fed an atherogenic diet for 4 months and the diet was then supplemented with 10% v/w of virgin olive oil (OO group), sunflower oil (SO group) or fish oil (FO group) for 4 and 8 weeks. Blood samples were collected at four time points: at baseline, after feeding with the atherogenic diet and during the dietary regimen (4 and 8 weeks). Plasma lipid profile and lipoprotein oxidative susceptibility (LOS), C-reactive protein (CRP), monocyte chemoattractant protein (MCP-1), and regulated upon activation normal T-cell expressed and secreted (RANTES) were measured. The superoxide dismutase (SOD) and reduced glutathione (GSH) antioxidant activities were also studied in aortic segments. Histological assessment of the aortic segment was determined. Compared to baseline data, the high-fat and cholesterol-enriched diet increased atheroma formation, plasma LOS and inflammatory indexes (CRP, MCP-1, RANTES). However, it dramatically reduced aortic SOD and GSH contents. Dietary treatment of atherosclerotic rats with OO greatly reduced LOS and remarkably increased aortic SOD and GSH contents as compared to the SO- and FO-treated groups. The FO-supplemented diet had a more pronounced lowering effect on MCP-1 and RANTES compared to the OO and SO diets. In conclusion, this study demonstrated a strong relationship between LOS and circulating levels of chemokines. OO is a potent antioxidant and moderate anti-inflammatory, which effectively reduced aortic atherosclerotic lesions more than the SO- or FO-treated groups in male Wistar rats. 相似文献
706.
Hadeel M. Seif El Dien Reem I. Esmail Rania E. Magdy Hala M. Lotfy 《Pediatric radiology》2013,43(9):1159-1165
Background
Current thalassemia major treatment includes blood transfusion and iron chelation, which is associated with growth disturbances and radiographic changes in the long bone metaphyses.Objective
To explore and discuss the spectrum of deferoxamine-induced bone-dysplasia-like changes in children with thalassemia major in Egypt.Materials and methods
We studied 59 Egyptian children with thalassemia major and generalized arthralgia. All started deferoxamine treatment at 3 years of age. We conducted skeletal survey and MRI of both knees in radiographically positive children. Each child’s age, serum ferritin, age of onset and duration of therapy were compared with the radiologic findings.Results
Twenty-two (37.3%) children had variable degrees of skeletal dysplasia-like changes similar to those described with deferoxamine intake, mostly around the knees. Mild dysplasia-like changes were seen in 4 (18%) children; moderate changes were seen in 11 (50%) children and severe changes were seen in 7 (31.8%) children. No statistically significant relationships were detected between bone changes and the children’s age, age of starting deferoxamine, duration of therapy, or serum ferritin level.Conclusion
A wider spectrum of deferoxamine-induced bone-dysplasia-like changes was recognized despite delayed onset and small doses of therapy. These changes should be considered as a possible cause of arthropathy in children with thalassemia major, especially symptomatic children. 相似文献707.
Al Safarjalani ON Rais RH Kim YA Chu CK Naguib FN el Kouni MH 《Biochemical pharmacology》2008,76(8):958-966
Toxoplasma gondii adenosine kinase (EC.2.7.1.20) is the major route of adenosine metabolism in this parasite. The enzyme is significantly more active than any other enzyme of the purine salvage in T. gondii and has been established as a potential chemotherapeutic target for the treatment of toxoplasmosis. Certain 6-benzylthioinosines act as subversive substrates of T. gondii, but not human, adenosine kinase. Therefore, these compounds are preferentially metabolized to their respective nucleotides and become selectively toxic against the parasites but not their host. Moreover, 7-deazaadenosine (tubercidin) was shown to be an excellent ligand of T. gondii adenosine kinase. Therefore, we synthesized 7-deaza-6-benzylthioinosine, and analogues with various substitutions at their phenyl ring, to increase the binding affinity of the 6-benzylthioinosines to T. gondii adenosine kinase. Indeed, the 7-deaza-6-benzylthioinosine analogues were better ligands of T. gondii adenosine kinase than the parent compounds, 6-benzylthioinosine and 7-deazainosine. Herein, we report the testing of the metabolism of these newly synthesized 7-deaza-6-benzylthioinosines, as well as their efficacy as anti-toxoplasmic agents in cell culture. All the 7-deaza-6-benzylthioinosine analogues were metabolized to their 5′-monophosphate derivatives, albeit to different degrees. These results indicate that these compounds are not only ligands but also substrates of T. gondii adenosine kinase. All the 7-deaza-6-benzylthioinosine analogues showed a selective antitoxoplasmic effect against wild type parasites, but not mutants lacking adenosine kinase. The efficacy of these compounds varied with the position and nature of the substitution on their phenyl ring. Moreover, none of these analogues exhibited host toxicity. The best compounds were 7-deaza-6-(p-methoxybenzylthio)inosine (IC50 = 4.6 μM), 7-deaza-6-(p-methoxycarbonylbenzylthio)inosine (IC50 = 5.0 μM), and 7-deaza-6-(p-cyanobenzylthio)inosine (IC50 = 5.3 μM). These results further confirm that T. gondii adenosine kinase is an excellent target for chemotherapy and that 7-deaza-6-benzylthioinosines are potential antitoxoplasmic agents. 相似文献
708.
The purpose of this investigation was to evaluate whether senior dental students (4DS) could serve as effective instructors in a two-semester preclinical laboratory course and whether such teaching experience could enhance their interest in academics as a future career. Based on academic performance, five senior students were recruited to serve as instructors in a two-semester morphology/occlusion laboratory course in which ninety-five first-year dental students were enrolled. The first-year students were randomly assigned so that each student was instructed by a faculty member in one semester and a 4DS in the other semester. Outcomes included course evaluation forms completed by the first-year dental students at the end of each semester; a comparison of students' performances in each course determined by faculty instructors and 4DSs; and the 4DSs' self-report of their teaching experiences. Results showed no significant difference between the performance of 4DS and faculty instructors in all criteria evaluated (p>.05). Furthermore, there was no significant difference between the performance of students instructed by faculty members and those instructed by 4DS in either semester (p>.05). Despite the fact that such experience seemed to have minimal influence on students' decision to consider academics as a future career, 4DSs do seem to provide effective instruction and thereby can serve to compensate for faculty shortages. 相似文献
709.
Reem M. Ghandour Jessica R. Jones Lydie A. Lebrun-Harris Jessica Minnaert Stephen J. Blumberg Jason Fields Christina Bethell Michael D. Kogan 《Maternal and child health journal》2018,22(8):1093-1102
Introduction Since 2001, the Health Resources and Services Administration’s Maternal and Child Health Bureau (HRSA MCHB) has funded and directed the National Survey of Children’s Health (NSCH) and the National Survey of Children with Special Health Care Needs (NS-CSHCN), unique sources of national and state-level data on child health and health care. Between 2012 and 2015, HRSA MCHB redesigned the surveys, combining content into a single survey, and shifting from a periodic interviewer-assisted telephone survey to an annual self-administered web/paper-based survey utilizing an address-based sampling frame. Methods The U.S. Census Bureau fielded the redesigned NSCH using a random sample of addresses drawn from the Census Master Address File, supplemented with a unique administrative flag to identify households most likely to include children. Data were collected June 2016–February 2017 using a multi-mode design, encouraging web-based responses while allowing for paper mail-in responses. A parent/caregiver knowledgeable about the child’s health completed an age-appropriate questionnaire. Experiments on incentives, branding, and contact strategies were conducted. Results Data were released in September 2017. The final sample size was 50,212 children; the overall weighted response rate was 40.7%. Comparison of 2016 estimates to those from previous survey iterations are not appropriate due to sampling and mode changes. Discussion The NSCH remains an invaluable data source for key measures of child health and attendant health care system, family, and community factors. The redesigned survey extended the utility of this resource while seeking a balance between previous strengths and innovations now possible. 相似文献
710.
The frequency of HLA genes in one population may not accurately represent frequencies in other populations. In this study, we characterized extended human leukocyte antigen (HLA) haplotypes in several families of Kuwaiti descent by high-resolution typing using next-generation technology. A total 81 members (including patients and related donors) from 21 families were enrolled. No haplotypes were shared among multiple families. Of 77 haplotypes identified, 23 were not listed in the HaploStats database. Two haplotypes were most common in African Americans, six in Asian Pacific Islanders, three in Caucasians, three in Hispanics, and three in Native Americans. The remaining identified haplotypes were not among the most common 200 HLA haplotypes in any of the five major populations. This cohort had 202 (19%) unique alleles, including 20 rare alleles, 16 very rare alleles, and 2 novel ones. Furthermore, no frequency data were available for 30% (23/77) of the observed haplotypes, and 6% (3/49) of B?~?C blocks identified were not available in the HaploStats database. Kuwaiti individuals carry unique HLA haplotypes that are not shared by the majority of individuals historically reported to the US National Marrow Donor Program registry. 相似文献