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101.
OBJECTIVE: To estimate the proportion and characteristics of U.S. pediatricians who reportedly counsel their patients about maintaining a healthy weight. RESEARCH METHODS AND PROCEDURES: Beginning in October 1998, information was collected from 813 primary care pediatricians randomly selected from a nationally representative sample. Pediatricians were asked how frequently they counseled about maintaining a healthy weight during the well-care visits of patients in three age groups. Multivariable logistic regression determined which physician characteristics were associated with counseling. RESULTS: Approximately fifty percent of pediatricians reportedly always counseled about maintaining a healthy weight. Those who always counseled were more likely to be women, to spend more time with patients during well-care visits, and to conduct more well-care visits per week from patients in one particular age group. Most pediatricians who responded that they always counseled about healthy weight reported that they counseled about physical activity and nutrition, but not about balancing caloric intake with expenditure. DISCUSSION: Although many pediatricians report counseling about healthy weight, the frequency of counseling might be further increased by increasing the amount of time the patient spends during office visits with the pediatrician or with other professional staff, such as nurses or dietitians. 相似文献
102.
Flair J Carrilho Cleusa R Moraes João RR Pinho Isabel MVGC Mello Dennis A Bertolini Marcílio F Lemos Regina C Moreira Leda C Bassit Rita A Cardoso Gabriela Ribeiro-dos-Santos Luiz C Da Silva 《BMC public health》2004,4(1):1-11
Background
Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil.Methods
This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units.Results
Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection.Conclusions
Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters ≥ 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission. 相似文献103.
An unsupervised approach to identify molecular phenotypic components influencing breast cancer features 总被引:2,自引:0,他引:2
Selaru FM Yin J Olaru A Mori Y Xu Y Epstein SH Sato F Deacu E Wang S Sterian A Fulton A Abraham JM Shibata D Baquet C Stass SA Meltzer SJ 《Cancer research》2004,64(5):1584-1588
To discover a biological basis for clinical subgroupings within breast cancers, we applied principal components (PCs) analysis to cDNA microarray data from 36 breast cancers. We correlated the resulting PCs with clinical features. The 35 PCs discovered were ranked in order of their impact on gene expression patterns. Interestingly, PC 7 identified a unique subgroup consisting of estrogen receptor (ER); (+) African-American patients. This group exhibited global molecular phenotypes significantly different from both ER (-) African-American women and ER (+) or ER (-) Caucasian women (P < 0.001). Additional significant PCs included PC 4, correlating with lymph node metastasis (P = 0.04), and PC 10, with tumor stage (stage 2 versus stage 3; P = 0.007). These results provide a molecular phenotypic basis for the existence of a biologically unique subgroup comprising ER (+) breast cancers from African-American patients. Moreover, these findings illustrate the potential of PCs analysis to detect molecular phenotypic bases for relevant clinical or biological features of human tumors in general. 相似文献
104.
This study evaluated five dementia-specific quality of life (DQOL) measures including client interviews, staff proxies, and observations with 54 clients in three adult day centers. Also, the relationship of cognitive and functional status to each of the DQOL measures was assessed. Client interviews correlated well with each other, but not with other measures. Staff proxies were strongly correlated with each other and moderately correlated with the observational measure. On average, clients rated their DQOL higher than staff. Analyses suggest that functional impairment is associated with poorer DQOL as indicated by staff and observer measures. Possible explanations and implications are explored. 相似文献
105.
Forsyth PA Weaver S Fulton D Brasher PM Sutherland G Stewart D Hagen NA Barnes P Cairncross JG DeAngelis LM 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》2003,30(2):106-112
OBJECTIVE: We conducted a clinical trial to determine if prophylactic anticonvulsants in brain tumour patients (without prior seizures) reduced seizure frequency. We stopped accrual at 100 patients on the basis of the interim analysis. METHODS: One hundred newly diagnosed brain tumour patients received anticonvulsants (AC Group) or not (No AC Group) in this prospective randomized unblinded study. Sixty patients had metastatic, and 40 had primary brain tumours. Forty-six (46%) patients were randomized to the AC Group and 54 (54%) to the No AC Group. Median follow-up was 5.44 months (range 0.13-30.1 months). RESULTS: Seizures occurred in 26 (26%) patients, eleven in the AC Group and 15 in the No AC Group. Seizure-free survivals were not different; at three months 87% of the AC Group and 90% of the No AC Group were seizure-free (log rank test, p = 0.98). Seventy patients died (unrelated to seizures) and survival rates were equivalent in both groups (median survival = 6.8 months versus 5.6 months, respectively; log rank test, p = 0.50). We then terminated accrual at 100 patients because seizure and survival rates were much lower than expected; we would need > or = 900 patients to have a suitably powered study. CONCLUSIONS: These data should be used by individuals contemplating a clinical trial to determine if prophylactic anticonvulsants are effective in subsets of brain tumour patients (e.g. only anaplastic astrocytomas). When taken together with the results of a similar randomized trial, prophylactic anticonvulsants are unlikely to be effective or useful in brain tumour patients who have not had a seizure. 相似文献
106.
107.
Determination of acute mortality in adults and sublethal embryo responses of Palaemonetes pugio to endosulfan and methoprene exposure 总被引:1,自引:0,他引:1
Adult grass shrimp (Palaemonetes pugio) were exposed to endosulfan or methoprene for 96 h and LC(50) values were calculated. Male and female P. pugio cohorts were also exposed to endosulfan for 96 h in an attempt to determine potential differences in sensitivity between the sexes. Results from the methoprene exposure indicated that this pesticide was not acutely toxic to adult grass shrimp at 1 mg l(-1). Due to the lack of sensitivity, sex specific tests with methoprene were not performed. The calculated LC(50) for a population of grass shrimp, including both males and females exposed to endosulfan, was 0.62 microg l(-1). The LC(50) determinations for the sex specific tests were 0.92 microg l(-1) for males and 1.99 microg l(-1) for females. Following these acute exposures, reproductively active grass shrimp were chronically exposed to 200 ng l(-1) endosulfan or 1 mg l(-1) methoprene and were allowed to produce embryos. The resulting embryos were assessed for potential sublethal toxicity. There were no observed differences in the percent successfully hatching or larval mortality 3-days post hatch among the treatments. However, endosulfan treated embryos had a significantly increased hatching time (9.76 days compared to 8.72 days in controls). Methoprene treated embryos also took longer to hatch (9.55 days), but this delay was not significantly different from controls. These findings suggest that endosulfan may preferentially affect male grass shrimp and exposed female grass shrimp may produce embryos with delayed hatching times. 相似文献
108.
Snaddon J Parkinson EK Craft JA Bartholomew C Fulton R 《British journal of cancer》2001,84(12):1630-1634
The human tumour suppressor gene PTEN located at 10q23 is mutated in a variety of tumour types particularly metastatic cases and in the germline of some individuals with Cowdens cancer predisposition syndrome. We have assessed the status of PTEN and associated pathways in cell lines derived from 19 squamous cell carcinomas of the head and neck. Loss of heterozygosity is evident at, or close to the PTEN gene in 5 cases, however there were no mutations in the remaining alleles. Furthermore by Western analysis PTEN protein levels are normal in all of these SCC-HN tumours and cell lines. To assess the possibility that PTEN may be inactivated by another mechanism, we characterized lipid phosphatase levels and from a specific PIP3 biochemical assay it is clear that PTEN is functionally active in all 19 human SCCs. Our data strongly suggest the possibility that a tumour suppressor gene associated with development of SCC-HN, other than PTEN, is located in this chromosomal region. This gene does not appear to be MXI-1, which has been implicated in some other human tumour types. PTEN is an important negative regulator of PI3Kinase, of which subunit alpha is frequently amplified in SCC-HN. To examine the possibility that PI3K is upregulated by amplification in this tumour set we assessed the phosphorylation status of Akt, a downstream target of PI3K. In all cases there is no detectable increase in Akt phosphorylation. Therefore there is no detectable defect in the PI3K pathway in SCC-HN suggesting that the reason for 3q26.3 over-representation may be due to genes other than PI3K110alpha. 相似文献
109.
The recent increase in the prevalence of paediatric obesity is one of the most pressing public health concerns today because of the immediate and long term health consequences associated with this often intractable disease. Efforts are currently being made to reduce the prevalence of paediatric obesity. Youth weight loss studies have produced significant long term results. Most of these programmes included behaviour modification, diet and exercise. Studies have suggested that lifestyle exercise programmes may produce the best long term results. Effective components of these programmes appear to be parental involvement, reduced intake of foods having high energy density and reductions in physical inactivity. Future weight loss studies need to determine the type, intensity, and duration of exercise that will produce acceptable adherence and consequent long term weight loss, and to ascertain the reinforcing factors that determine youth behaviour choice. Weight gain prevention interventions for youth are clearly in their infancy. This review describes 3 completed and 2 ongoing weight gain prevention trials. One study showed reductions in the prevalence of obesity among junior high school girls, but not among boys. Another study among elementary school students showed significant mean decreases in body mass index in boys and girls following an intervention specifically to reduce time spent viewing television. Whether these studies altered food intake or increased physical activity remains unclear. A combination of weight loss treatment and weight gain prevention strategies employed in parallel is likely to yield the greatest benefits. Development and testing of novel intervention strategies, using innovative behavioural approaches to increase the likelihood that children will adopt healthy dietary, physical activity, and sedentary behaviour patterns, holds great promise to significantly reduce the epidemic of obesity. 相似文献
110.
Grass shrimp, Palaemonetes pugio, are common inhabitants of salt marshes along the Atlantic and Gulf coasts of North America. Grass shrimp embryos are brooded externally on the abdomen of adult females for about 2 weeks prior to hatching. In South Carolina, the spring spawning period for grass shrimp coincides with the period of peak pesticide application on crops grown along the South Carolina coast. Thus, grass shrimp of all developmental stages are at risk of exposure to pesticides present in nonpoint source agricultural runoff. Organophosphate (OP) insecticides are commonly applied agricultural chemicals which produce toxicity by inhibiting the nervous system enzyme, acetylcholinesterase (AChE). The purpose of this study was to examine the development of AChE activity in grass shrimp embryos and to assess their sensitivity to OP-induced AChE inhibition. Embryos were exposed for 24 h to either chlorpyrifos or malathion. All exposure concentrations were nominal and ranged from 0 to 2.00 μg l(-1) for chlorpyrifos and from 0 to 120.00 μg l(-1) for malathion. Quantifiable levels of AChE activity first appeared at Stage V of development and increased as embryonic development progressed. AChE inhibition by the OPs was assessed in Stage VI and Stage VII embryos. Both stages of embryos were more sensitive to chlorpyrifos than malathion. The 24-h Effective Concentration (EC(50)) values for chlorpyrifos were 0.49 μg l(-1) (95% C.I.=0.33-0.77 μg l(-1)) and 0.36 μg l(-1) (95% C.I.=0.33-0.38 μg l(-1)) for Stage VI and Stage VII embryos, respectively. In comparison, malathion 24-h EC(50) values were 55.53 μg l(-1) (95% C.I.=22.08-80.73 μg l(-1)) for Stage VI embryos and 29.93 μg l(-1) (95% C.I.=25.22-44.22 μg l(-1)) for Stage VII embryos. For both OPs, there were no significant differences in the EC(50) values calculated for Stage VI and Stage VII embryos; however, AChE inhibition was significantly (P=0.05) greater in Stage VII embryos at the two highest exposure concentrations for each insecticide. A comparison of the results of these embryo tests with those found for adult and larval toxicity tests indicated that embryos were at least as sensitive to both the OPs as larval and adult grass shrimp. Embryo bioassays provide a number of important advantages over traditional laboratory toxicity tests including reduced laboratory space requirements, large numbers of embryos from a few ovigerous females, and small volumes of waste. 相似文献