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81.
The spectral response curve (amplitude versus wavelength) of the R2 of the early receptor potential (ERP) was studied in normal, protan, and deutan subjects. The R2 amplitude peaked at 520nm in most normal subjects. The R2 at long wavelengths was smaller than normal in protans and larger than normal in deutans when the maximum amplitudes were normalized to 100% at the peak. The ratio of the R2 amplitude at 460 nm to that at 600 nm clearly differed between protans and deutans. The ERP and the rapid off-response, which is mainly due to the cessation of the late receptor potential, were recorded in the same subjects. The ratio of the sensitivity of the rapid off-response at 500 nm to that at 600 nm was correlated with the ratio of the R2 amplitude at 460 nm to that at 600nm (correlation coefficient, 0.823, p < 0.001). This study, in conjunction with our previous study, indicates that the abnormality is in the outer segments of the cones in protans and deutans.  相似文献   
82.
Introduction Hypothalamic hamartomas are congenital malformations. Clinically, they can be asymptomatic, but they cause seizures, mental retardation and precocious puberty in many cases. Case report A 20-day-old boy with hypothalamic hamartoma and bilateral anophthalmia was presented. Except those, no other congenital anomaly was detected. Conclusion This is a rare case of hypothalamic hamartoma with bilateral anophthalmia. The mutations at SOX2 has an important role in the developing brain and eyes.  相似文献   
83.
Physical activity is an important, but often underused, therapeutic strategy within diabetes care. To date, little is known about the best way to promote physical activity in diabetes care. Physical activity consultation is an intervention designed to promote physical activity behaviour change. This article provides guidelines on how to conduct a physical activity consultation with people who have Type 2 diabetes, and reviews the evidence surrounding the effectiveness of this intervention in this population. The trans-theoretical model is the underlying theory of behaviour change for the physical activity consultation intervention. The review identifies research which supports the use of this model for understanding physical activity behaviour in people with Type 2 diabetes. The review outlines a number of modifiable variables associated with physical activity behaviour change in this population. How each of these variables is addressed within the guidelines for conducting a physical activity consultation is identified. Finally, limited but consistent research highlights the effectiveness of physical activity consultation for promoting physical activity in people with Type 2 diabetes.  相似文献   
84.
目的 建立单侧缺氧缺血性脑损伤 (HIBD)动物模型 ,研究胰岛素样生长因子 1(IGF 1)对HIBD的影响和可能机制。 方法 选择健康 7日龄Wistar大鼠 12 0只 ,建立HIBD模型 ,随机分成假手术组、HIBD组、HIBD后 0 .2mg/kg人基因重组IGF 1干预组 (RH IGF 1组 )、0 .0 6 6mg/kg人基因重组IGF 1干预组 (SRH IGF 1组 )及盐水对照组 (对照组 )。各组按观察时段进一步分为 2 4、4 8、72h组 ,每组 8只。各组于规定时刻观测脑形态学改变、谷氨酸 (Glu)含量、凋亡细胞计数、Bcl 2蛋白表达。 结果  (1)HIBD 4 8h组Glu(116 2 .2± 10 8.1)mg/kg ,较假手术组(75 0 .9± 5 3.4 )mg/kg明显升高 (P <0 .0 5 ) ;HIBD组凋亡细胞计数 [2 4h :(7.6± 1.9) % ,4 8h(12 .6±1.2 ) % ,72h :(13.8± 0 .9) % ],较假手术组 [2 4h(2 .0± 0 .2 ) % ,4 8h(2 .0± 0 .3) % ,72h(2 .0±0 .2 ) % ]明显增加 (P均 <0 .0 5 )。 (2 )与对照组相比 ,RH IGF 1组脑组织病变减轻 ;干预 4 8h组Glu[SRH IGF 1组 (781.4± 5 4 .2 )mg/kg ,RH IGF 1组 (74 0 .5± 4 6 .6 )mg/kg],较对照组 (112 6 .6± 4 8.0 )mg/kg明显降低 (P均 <0 .0 5 ) ;RH IGF 1组凋亡细胞计数 [2 4h :(3.6± 0 .9) % ,4 8h(8.2± 2 .2 ) % ,72h(9.4± 1.4 ) % ],较对  相似文献   
85.
Atopy may be associated with a reduced T-cell function early in life, particularly regarding maturation of Th1 responses. The T-cell surface molecules CD2 and CD28 are involved in important T-cell activation pathways. Stimulation via the CD2 receptor increases the responsiveness to interleukin (IL)-12, which is a potent inducer of Th1 responses, whereas CD28 stimulation is critical for Th2 differentiation. Our aim was to prospectively study the expression of the cell-surface markers CD2 and CD28 on T-cells in relation to development of atopic disease. Children (n = 172) were followed from birth to 18 months and the cumulative history of atopic disease was recorded. Blood samples were obtained at birth and at 18 months, and in a subgroup of 78 infants also at 3, 6 and 12 months. Flow cytometry was used to analyze the T-cell markers CD2 and CD28, the latter also within the subsets of T-helper (CD4+) and T-cytotoxic (CD8+) cells. At 18 months, 31 children had and 118 did not have atopic symptoms. At this age, skin prick test (SPT) positive children with atopic symptoms with or without an atopic family history (AFH) showed a lower expression of CD2 mode fluorescence intensity (FI) as well as a lower proportion of CD2+ cells, as compared with non-sensitized children with neither atopic symptoms nor AFH. This was accompanied by a higher expression of CD28 FI on CD2+CD8+CD28+ cells. No significant differences were seen at time points before 18 months, although the proportion of CD2+ tended to be low also earlier in life. In conclusion, the observed reduced expression of CD2 in atopic infants may support previous findings that atopy is associated with a reduced CD2 function. The high CD28 FI in SPT positive children with atopic symptoms may possibly be a consequence of a TH2-skewed immune system.  相似文献   
86.
AIMS: The efficacy of three education programmes for Type 2 diabetic patients was tested in a randomized trial. A didactic-oriented training programme (treatment A) was compared with a self-management-oriented programme delivered in group sessions (treatment B). The latter programme was compared with a more individualized approach (treatment C). METHODS: One hundred and eighty-one Type 2 diabetic patients (age 55.6 +/- 6.3 years, diabetes duration 6.6 +/- 6.2 years, HbA(1c) 7.8 +/- 1.6%, female 49.7%) took part. Efficacy was assessed 3 months (t1) after baseline (t0) and at a follow-up 15 months (t2) after baseline. RESULTS: The fall in HbA(1c) in treatment B at t1 was sustained at t2 (t0 8.1 +/- 1.8%, t1 7.3 +/- 1.7%, t2 7.4 +/- 1.9%). In treatment A, HbA(1c) was unchanged throughout (t0 7.6 +/- 1.5%, t1 7.5 +/- 1.3%, t2 7.7 +/- 1.7%; treatment A vs. treatment B; P < 0.05). With the more individualized approach of treatment C, there was a fall in HbA(1c) at t1, but this was not sustained at t2 (t0 7.8 +/- 1.6%, t1 7.1 +/- 1.3%, t2 7.6 +/- 1.6%; treatment B vs. treatment C; P = 0.73). There were also significant benefits in treatment B subjects compared with treatment A in further medical (body mass index and fasting blood glucose), psychological (control, irritability and hunger dependency of eating behaviour, and trait anxiety) and behavioural (exercise) variables. There were no significant benefits of the more individualized treatment C compared with group treatment B. No significant differences were found regarding triglyceride levels, high-density lipoprotein, diabetes-related knowledge, negative well-being, urine or blood glucose levels or foot care. CONCLUSION: Self-management training had a significantly higher medium-term efficacy than didactic diabetes education. The group sessions were more effective than a more individualized approach.  相似文献   
87.
AIMS: Diabetic ketoacidosis (DKA), a life-threatening acute complication of Type 1 diabetes, may be preventable with frequent monitoring of glycaemia and ketosis along with timely supplemental insulin. This prospective, two-centre study assessed sick day management using blood 3-hydroxybutyrate (3-OHB) monitoring compared with traditional urine ketone testing, aimed at averting emergency assessment and hospitalization. METHODS: One hundred and twenty-three children, adolescents and young adults, aged 3-22 years, and their families received sick day education. Participants were randomized to receive either a blood glucose monitor that also measures blood 3-OHB (blood ketone group, n = 62) or a monitor plus urine ketone strips (urine ketone group, n = 61). All were encouraged to check glucose levels > or = 3 times daily and to check ketones during acute illness or stress, when glucose levels were consistently elevated (> or = 13.9 mmol/l on two consecutive readings), or when symptoms of DKA were present. Frequency of sick days, hyperglycaemia, ketosis, and hospitalization/emergency assessment were ascertained prospectively for 6 months. RESULTS: There were 578 sick days during 21,548 days of follow-up. Participants in the blood ketone group checked ketones significantly more during sick days (276 of 304 episodes, 90.8%) than participants in the urine ketone group (168 of 274 episodes, 61.3%) (P < 0.001). The incidence of hospitalization/emergency assessment was significantly lower in the blood ketone group (38/100 patient-years) compared with the urine ketone group (75/100 patient-years) (P = 0.05). CONCLUSIONS: Blood ketone monitoring during sick days appears acceptable to and preferred by young people with Type 1 diabetes. Routine implementation of blood 3-OHB monitoring for the management of sick days and impending DKA can potentially reduce hospitalization/emergency assessment compared with urine ketone testing and offers potential cost savings.  相似文献   
88.
Aims Cardiovascular disease (CVD) is a major complication of Type 2 diabetes mellitus. The renin‐angiotensin system (RAS) and nitric oxide production are both important regulators of vascular function and blood pressure. Genes encoding proteins involved in these pathways are candidates for a contribution to CVD in diabetic patients. We have investigated variants of the angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin type 1 receptor (AT1R) and endothelial nitric oxide synthase (NOS3) genes for association with subclinical measures of CVD in families with Type 2 diabetes mellitus (T2DM). Methods Atherosclerosis was measured by carotid intima‐media thickness and calcification of the carotid and coronary arteries in 620 European Americans and 117 African Americans in the Diabetes Heart Study. Because of the role of these systems in blood pressure regulation, blood pressure was also investigated. Results Compelling evidence of association was not detected with any of the SNPs with any outcome measures after adjustments for covariates despite sufficient power to detect relatively small differences in traits for specific genotype combinations. Conclusions Genetic variation of the RAS and NOS3 genes do not appear to strongly influence subclinical cardiovascular disease or blood pressure in this diabetic population.  相似文献   
89.
The antiproliferative effect of As(2)O(3)-loaded microemulsion (As(2)O(3)-M) on human MDAH 2774 ovarian cancer cells was compared with a regular solution of the As(2)O(3). We used MDAH 2774 as model cell lines for ovarian cancer. The (2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide) (XTT) and trypane blue dye exclusion tests were used to evaluate cytotoxicity. Apoptotic effect of solutions was evaluated using cell death detection kit. Standard microemulsion formulation used in this experiment contains 5 x 10(-6) M As(2)O(3). It was clearly demonstrated that As(2)O(3)-M had a significant cytotoxic effect on MDAH 2774 cell line, and the cytotoxic effect of As(2)O(3)-M was significantly higher than that of regular As(2)O(3) solutions. Even approximately 6000 times diluted microemulsion formulation loaded with 5 x 10(-6) M As(2)O(3) showed a cytotoxic effect. As a result, this diluted concentration (approximately 8 x 10(-10) M) was found to be approximately 6000 times more effective than regular As(2)O(3) solutions (5 x 10(-6) M). Moreover, this diluted concentration resulted in 1.5-fold enhancement of apoptosis. According to the in vitro cytotoxicity studies, we concluded that by incorporating As(2)O(3) into the microemulsion (As(2)O(3)-M), which is a new drug carrier system, it is possible to increase antiproliferative effect of regular As(2)O(3) on MDAH 2774 cells. Translating these results to in vivo conditions would open new windows in the treatment of ovarian cancer.  相似文献   
90.
We studied 44 cases of Hodgkin's disease for the presence of Epstein-Barr virus (EBV) DNA, its localization and the expression of the EBV receptor on the tumour cells. EBV DNA was found in 52% (16/31) of the Hodgkin's lymphomas using the polymerase chain reaction. With a very sensitive non-radioactive DNA in situ hybridization technique in combination with immunohistochemistry for CD 30 or CD 15 antigens, EBV DNA was localized to Reed-Sternberg cells and its mononuclear variants. The relationship between the presence of EBV DNA and the expression of the EBV-receptor CR2 (CD 21) on Reed-Sternberg cells was studied using the same techniques and two different monoclonal anti-CD 21 antibodies. CR2 could be detected on a substantial number of the Reed-Sternberg cells in EBV DNA positive Hodgkin's lymphomas (9/12; 75%), whereas in EBV negative cases positivity with anti-CD 21 was rare (1/13; 8%). The results indicate that CR2 expression on Reed-Sternberg cells and the presence of EBV DNA sequences are frequently associated in Hodgkin's lymphomas.  相似文献   
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