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111.
Neurons and glia arise from neural progenitor cells that express nestin. Although substantial changes in neuronal development were observed during the postnatal period, data concerning dynamics of nestin expression in the superior cervical ganglia (SCG) of rat during that period are lacking. It is known that gonadectomy and steroid hormones influence the development of neurons in the SCG during the postnatal period, but there are no data on how they influence the persistence of nestin expression in the SCG cells.The dynamics of nestin expression in the SCG in rats of three age groups, as well as the influence of gender and gonadectomy, was investigated.Three groups of male rats were sacrificed at 2, 3 and 6 months of age. Additional groups of male and female Sprague-Dawley rats were gonadectomized at the age of 2 months. After 30 days, they were sacrificed and SCGs were harvested and processed immunohistochemically. Immunoreactivity for nestin in the SCG was observed in satellite glia, based on their expression of s100. The proportion of neurons that were encircled with nestin-immunoreactive satellite cells (nestin encircled neurons, NEN) decreased between second and third month of age (p < 0.05). The proportion of NEN was greater in the NPY+ than in the NPY− subpopulation. The proportion of NEN in the SCG of female rats was significantly higher (p < 0.05) than that of both, the male rats and ovariectomised groups. The percentage of these neurons was significantly higher (p < 0.05) in orchidectomised, in comparison to male rats.Results show the existence of nestin-immunoreactive satellite cells in the SCG of adult rats. A substantial decrease of nestin expression in SCG cells of rats, after the onset of sexual maturation, was observed. This decrease showed significant sex-dependence and was dramatically influenced by gonadal activity. 相似文献
112.
Radiology report errors occur for many reasons including the use of pre-filled report templates, wrong-word substitution, nonsensical phrases, and missing words. Reports may also contain clinical errors that are not specific to the speech recognition including wrong laterality and gender-specific discrepancies. Our goal was to create a custom algorithm to detect potential gender and laterality mismatch errors and to notify the interpreting radiologists for rapid correction. A JavaScript algorithm was devised to flag gender and laterality mismatch errors by searching the text of the report for keywords and comparing them to parameters within the study’s HL7 metadata (i.e., procedure type, patient sex). The error detection algorithm was retrospectively applied to 82,353 reports 4 months prior to its development and then prospectively to 309,304 reports 15 months after implementation. Flagged reports were reviewed individually by two radiologists for a true gender or laterality error and to determine if the errors were ultimately corrected. There was significant improvement in the number of flagged reports (pre, 198/82,353 [0.24 %]; post, 628/309,304 [0.20 %]; P = 0.04) and reports containing confirmed gender or laterality errors (pre, 116/82,353 [0.014 %]; post, 285/309,304 [0.09 %]; P < 0.0001) after implementing our error notification system. The number of flagged reports containing an error that were ultimately corrected improved dramatically after implementing the notification system (pre, 17/116 [15 %]; post, 239/285 [84 %]; P < 0.0001). We developed a successful automated tool for detecting and notifying radiologists of potential gender and laterality errors, allowing for rapid report correction and reducing the overall rate of report errors. 相似文献
113.
Beth Bennett Mary Beeson Lena Gordon Thomas E. Johnson 《Alcoholism, clinical and experimental research》1997,21(5):767-772
Numerous algorithms for the identification and genetic mapping of quantitative trait loci (QTL) have been developed. Methods for confirming QTL maps involve either examination of independent segregating populations or the construction of congenic lines differing only in the QTL of interest. Because these projects require a minimum of several years or thousands of marker assessments in laboratory mice, an alternative, faster congenic method has been pro: posed. In a preliminary study, we tested this method for confirming QTLs identified in crosses between the ILS and ISS selected lines of mice for differential sensitivity to the hypnotic effects of ethanol. Herein, we report the construction of "segregating congenic" strains in which each QTL is made homozygous in a single generation, whereas the remainder of the genetic background is allowed to segregate. Sensitivity to ethanol among the progeny of such mice is consistent with predictions. Phenotypic variation is high, as expected, due to the background segregation, and statistical significance was attained in only 2 of 7 comparisons. Such segregating congenic populations may be a valuable research tool for confirming QTL map positions and for subsequent assessment of individual pathways and mechanisms of action of individual QTLs. 相似文献
114.
Lü P Liu F Wang CY Chen DD Yao Z Tian Y Zhang JH Wu YH 《World journal of gastroenterology : WJG》2005,11(22):3441-3445
AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated with endothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO). METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissue malondialdehyde (MDA) content, and severity of hepatic I/R injury. RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs45.3μ10.1 μmol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P<0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs668.7±78.7 U/L, 1.71±0.18μg/L and 0.86±0.11 μmol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β-estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P<0.01). The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P<0.01 and P<0.05). The NOS inhibitor Nw-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOS-derived NO. 相似文献
115.
《Health policy (Amsterdam, Netherlands)》2015,119(6):840-849
We investigated whether the universal provision of long-term care (LTC) under Japan's public system has equalized its use across households with different socio-economic characteristics, with a special focus on the gender and marital status of primary caregivers, and income. We used repeated cross-sectional data from national household surveys (2001, 2004, 2007, and 2010) and conducted multiple logistic regression analyses to obtain odds ratios of caregiver and household characteristics for service use, adjusting for recipients’ characteristics. The results showed that the patterns of service use have been consistently determined by caregivers’ gender and marital status over the period despite demographic changes among caregivers. The gap in service use first narrowed, then widened again across income levels after the global economic recession. The results indicate that the traditional gender-bound norms and capacity constraints on households’ informal care provision remained influential on decisions over service use, even after the universal provision of formal care. To improve equality of service utilization, the universal LTC system needs to meet diversifying needs of caregivers/recipients and their households, by overcoming barriers related to gender norms and economic disparity. 相似文献
116.
《Health & place》2015
Adolescent substance use is a developmentally contingent social practice that is constituted within the routine social-environment of adolescents' lives. Few studies have examined peer networks, perceived activity space risk (risk of substance use at routine locations), and substance use. We examined the moderating influence of peer network characteristics on the relationship between perceived activity space risk and substance use among a sample of 250 urban adolescents. Significant interactions were found between peer networks and perceived activity space risk on tobacco and marijuana use, such that protective peer networks reduced the effect of activity place risk on substance use. A significant 3-way interaction was found on marijuana use indicating that gender moderated peer network's effect on activity space risk. Conditional effect analysis found that boys' peer networks moderated the effect of perceived activity space risk on marijuana use, whereas for girls, the effect of perceived activity space risk on marijuana use was not moderated by their peer networks. These findings could advance theoretical models to inform social–environmental research among adolescents. 相似文献
117.
AIMS/HYPOTHESIS: We determined the longitudinal relationship between adiponectin levels and the development of microalbuminuria in an inception cohort of children with type 1 diabetes. METHODS: Blood samples collected annually over a median of 9.0 (range 1.3-14.9) years were assayed for adiponectin and HbA(1c) in 55 children (36 girls) with type 1 diabetes and microalbuminuria whose age of onset of diabetes was 9.4 years (range 2.2-15.4). Samples were also assayed from normoalbuminuric children (controls) matched for age, sex and duration of diabetes. RESULTS: Overall, adiponectin levels were higher in girls than in boys, but only after 11 years of age (median [range]: 15.3 [5.8-124.4] vs 11.6 [4.1-26.5] mg/l, p < 0.001). Furthermore, adiponectin levels were higher in girls with microalbuminuria than in control girls, but this was only apparent after the onset of microalbuminuria (p = 0.001, adjusted for BMI, daily insulin dose, HbA(1c) and age). In boys, adiponectin levels did not differ between those with microalbuminuria and controls. Further sex-related discordant associations with adiponectin levels were observed; in girls, adiponectin levels were positively related to HbA(1c) levels (r = 0.2, p = 0.05) and urine albumin excretion (r = 0.3, p < 0.05) and inversely related to BMI (r = -0.2, p < 0.05). These associations were absent in boys. CONCLUSIONS/INTERPRETATION: In adolescent girls with type 1 diabetes but not in boys, adiponectin levels increase with increasing urine albumin excretion and onset of microalbuminuria. Although causal links cannot be inferred, this sexual dimorphism may reflect interactive effects of hyperglycaemia and sex steroids on risk of complications and adiponectin production. 相似文献
118.
Collins E. Lewis Kathleen K. Bucholz Edward Spitznagel Joseph J. Shayka 《Alcoholism, clinical and experimental research》1996,20(3):466-476
We investigated the influence of gender, comorbidity, drinking history, and age on the clinical manifestations of DSM-III alcohol abuse and/or dependence in men and women. The sample was drawn from the National Institute of Mental Health Epidemiologic Catchment Area study, a large-scale, multicenter survey to investigate psychiatric disorders in the community. The results showed that gender and comorbidity had independent effects on problem drinking after drinking history and age had been taken into account. Gender contributed to the age of onset of problem drinking and the rate of its development. Comorbidity, drinking history, and age contributed independently to its severity. The effects of these variables in this community sample paralleled those reported in treatment samples. 相似文献
119.
Malaria is one of the most serious public health problems in the world. For the last few decades, numerous studies have focused on the potential links between environmental transformations (such as the expansion of irrigation) and malaria occurrence. Most of these studies have been based on relatively simple models outlining the interactions of the host-vector-parasite triad. In this paper, we investigate the links between the intensification of irrigated rice cultivation and malaria. In an attempt to complement biomedical and entomological approaches we propose a model that recognises the influence of human-vector contacts on transmission processes, but stresses the importance of taking into consideration socio-economic and cultural factors in the management of disease episodes, and how these can be affected by transformations of natural resource management strategies. Using a case study in Northern C?te d'Ivoire, we investigated the complex mechanisms by which agriculture-generated changes in ecosystems and socio-economic organisation influence disease risks and produce new scenarios in the management of disease. Our results show that the socio-economic transformation and gender repositioning induced, or facilitated, by the intensification of lowland irrigated rice cultivation influence the health care system for malaria in the study area. They lead to a reduction of the capacity of women to manage malaria episodes among children and influence their vulnerability to the disease. We argue that these elements contribute to higher malaria prevalence in villages involved in double cropping of rice annually. 相似文献
120.
The aim of the present work was to investigate the impact of gender on resting cerebral blood flow velocity and cerebrovascular
reserve capacity among diabetic patients. Middle cerebral artery mean blood flow velocity (MCAV) was measured in 72 patients
suffering from type 1 diabetes mellitus at rest and 5, 10, 15 and 20 min after intravenous administration of 1 g acetazolamide.
Cerebrovascular reserve was calculated as the maximal percent increase in MCAV after acetazolamide. Resting MCAV and cerebrovascular
reserve capacity were compared between males and females. Resting cerebral blood flow velocity was higher in diabetic females
than in males (men, 55.0±17.0 cm/s; women, 64.4±12.6 cm/s, p=0.00094). Cerebrovascular reserve capacity was similar in diabetic women and men (men, 44.0%±18.6%; women, 52.6%±32.9%, p=0.17). Comparing MCAV and cerebrovascular reserve capacity among the diabetic subgroups with disease duration ≤10 years and
>10 years, we did not detect any differences between women and men. Duration of diabetes was an important factor in determining
cerebrovascular reserve capacity in both sexes: long-term diabetic women and men showed lower CRC values than diabetics with
≤10 years, disease duration. Cerebrovascular reserve capacity is similar in diabetic women and men. Taking into consideration
that cerebrovascular reserve is normally higher among women, our finding indicates a relatively more serious worsening of
cerebral vasodilatory responses in women suffering from type 1 diabetes.
Received: 20 May 2000 / Accepted in revised form: July 2001 相似文献