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排序方式: 共有243条查询结果,搜索用时 15 毫秒
1.
Pregnancy in acromegaly is a rather rare event since the fertility is reduced in acromegalic women. Besides, metabolic complications of acromegaly are harmful to both mother and fetus. Little is known about the outcome of pregnancy in acromegalic women. Here, we report seven cases of pregnancy out of 48 acromegalic women followed for 16 years. At diagnosis, five patients had macroadenoma, one patient had microadenoma and the size of the tumor was not documented in one patient. In one patient, acromegaly was initially diagnosed during pregnancy at 29 weeks. When she was 33 weeks, she developed pituitary apoplexy and had an emergency transsphenoidal resection of her macroadenoma during which she also had a cesarian section and delivered a healthy baby girl. In the remaining six patients, pregnancy occurred 6 to 64.5 months after the adenoma resection. Three patients received radiotherapy before getting pregnant. In three patients, pregnancy occurred during bromocriptine treatment and the drug was withdrawn. In one patient, pregnancy occurred during chronic octreotide treatment and therapeutic abortion was performed. In another patient, therapeutic abortion was performed because of uncontrolled disease. In the remaining four patients, there were neither worsening of symptoms nor tumor growth. All four patients gave birth to full-term healthy infants. Out of our seven patients, two developed gestational diabetes mellitus which was controlled with diet. None of the patients had coronary artery disease, hypertension or dyslipidemia. These cases show that pregnancy might be uneventful in acromegalic women when the disease is controlled with prior surgery and radiotherapy.  相似文献   
2.
Regional cerebral blood flow was investigated in 14 patients with major depression diagnosed according to the DSM-III-R criteria (six patients with single and eight patients with recurrent episodes) and in ten healthy volunteers. The mean ages of the patients and the controls were 33.5 ± 2.7 and 31.6 ± 2.6 years, respectively. The severity of the depression was assessed using the 17-item Hamilton Depression Scale (mean: 23.2 ± 1.5). None of the patients was under medication. After administration of 500 MBq technetium-99m hexamethylpropylene amine oxime, a single photon emission tomography study was performed and then transaxial, sagittal and coronal slices were obtained. For the semiquantitative analysis of the data, the ratios of the mean counts/pixel to the whole slice were calculated for 24 regions on three consecutive transaxial slices in the orbitomeatal plane. Additionally, left/right and frontal/occipital ratios were calculated. Both sides of the temporal region had a significantly decreased cerebral blood flow (CBF) when compared to the controls. The left/right ratio of the prefrontal region was also significantly lower in the patients than in the controls. The Hamilton score had a negative correlation with blood flow in the anterofrontal and left prefrontal regions. According to our results, regional CBF seems to be decreased in the left prefrontal and in both temporal regions in major depression. The severity of depression is correlated with the reduction in CBF in the regions of the anterofrontal and left prefrontal cortex.  相似文献   
3.
Asthma is a significant global public health issue. Severe asthma exacerbations can be triggered by environmental factors and require medical care from health services. Although it is known that fungal exposure may lead to allergic sensitization, little is understood about its impact on asthma exacerbations. This review aims to examine whether outdoor fungi play a significant role in child asthma exacerbations. Systematic search of seven electronic databases and hand searching for peer‐reviewed studies published in English, up to 31 August 2013. Inclusion criteria were study population aged <18 yr, diagnosis of asthma, attended a health service; outdoor fungi exposure was reported. Quality and risk of bias assessments were conducted. Due to significant heterogeneity, meta‐analysis was not conducted. Of the 1896 articles found, 15 were eligible. Findings were not consistent, possibly due to methodological variations in exposure classifications, statistical methods and inclusion of confounders. Cross‐sectional studies found no or weak associations. All but one time series studies indicated an association that varied between fungal species. Increasing evidence indicates that asthmatic children are susceptible to asthma exacerbations when exposed to outdoor fungal spores. There is limited understanding of the contributions of different fungal species. Research is needed to investigate interactions of outdoor fungi with pollen, air pollutants and respiratory viruses.  相似文献   
4.

Background

Millions of people can potentially be exposed to smoke from forest fires, making this an important public health problem in many countries.

Objective

In this study we aimed to measure the association between out-of-hospital cardiac arrest (OHCA) and forest fire smoke exposures in a large city during a severe forest fire season, and estimate the number of excess OHCAs due to the fire smoke.

Methods

We investigated the association between particulate matter (PM) and other air pollutants and OHCA using a case-crossover study of adults (≥ 35 years of age) in Melbourne, Australia. Conditional logistic regression models were used to derive estimates of the percent change in the rate of OHCA associated with an interquartile range (IQR) increase in exposure. From July 2006 through June 2007, OHCA data were collected from the Victorian Ambulance Cardiac Arrest Registry. Hourly air pollution concentrations and meteorological data were obtained from a central monitoring site.

Results

There were 2,046 OHCAs with presumed cardiac etiology during our study period. Among men during the fire season, greater increases in OHCA were observed with IQR increases in the 48-hr lagged PM with diameter ≤ 2.5 μm (PM2.5) (8.05%; 95% CI: 2.30, 14.13%; IQR = 6.1 μg/m3) or ≤ 10 μm (PM10) (11.1%; 95% CI: 1.55, 21.48%; IQR = 13.7 μg/m3) and carbon monoxide (35.7%; 95% CI: 8.98, 68.92%; IQR = 0.3 ppm). There was no significant association between the rate of OHCA and air pollutants among women. One hundred seventy-four “fire-hours” (i.e., hours in which Melbourne’s air quality was affected by forest fire smoke) were identified during 12 days of the 2006/2007 fire season, and 23.9 (95% CI: 3.1, 40.2) excess OHCAs were estimated to occur due to elevations in PM2.5 during these fire-hours.

Conclusions

This study found an association between exposure to forest fire smoke and an increase in the rate of OHCA. These findings have implications for public health messages to raise community awareness and for planning of emergency services during forest fire seasons.

Citation

Dennekamp M, Straney LD, Erbas B, Abramson MJ, Keywood M, Smith K, Sim MR, Glass DC, Del Monaco A, Haikerwal A, Tonkin AM. 2015. Forest fire smoke exposures and out-of-hospital cardiac arrests in Melbourne, Australia: a case-crossover study. Environ Health Perspect 123:959–964; http://dx.doi.org/10.1289/ehp.1408436  相似文献   
5.
Purpose

Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.

Methods

The radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.

Results

A total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.

Conclusions

Our analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.

  相似文献   
6.
Purpose: The present study investigated the correlation between extend aortic cross-clamping time and peripheral nerve injury on rats.Methods: 24 male, Sprague Dawley rats were divided into 3 groups; (a) control group: abdomen was directly closed after reached aorta, and followed by 72 hours, (b) short-term ischaemia-reperfusion group: peripheral nerve ischemia was induced in rats by supraceliac aortic occlusion for 20 min followed by 72 h of reperfusion, (c) long-term ischaemia-reperfusion group: peripheral nerve ischemia was induced for 30 min followed by 72 h of reperfusion. Preoperative and postoperative, electromyography (EMG) recordings were done. End of 72 h, the sciatic nerves were harvested from each animal for histopathological and biochemical analysis.Results: The mean compound muscle action potential (CMAP) amplitude of long-term ischaemia-reperfusion group was statically significant reduced when compared to the control group (p <0.01). However, the mean distal latency value of long-term ischaemia-reperfusion group was statically significant increased (p <0.01). On the other hand, there were statically significant differences between the results of malondialdehyde, edema and ischemia fiber degeneration grades on control and long-term ischaemia-reperfusion group (p <0.001).Conclusion: This study demonstrated that the extending cross clamping time directly harms the peripheral nerve of rats.  相似文献   
7.
Dagdelen  Selcuk  Cinar  Nese  Erbas  Tomris 《Pituitary》2014,17(4):299-306
Pituitary - Acromegaly increases cancer risk. We aimed to determine the prevalence and the predictors of tumors in acromegalic patients treated at our department. We retrospectively evaluated 160...  相似文献   
8.
Although understanding the relation between psychotic behavior and immune abnormalities has been the focus of research for many years, it remains to be elucidated whether the changes in cytokine levels are part of etiology or a result of the stress associated with the disorder. In accordance with previous studies on changes in cytokine levels due to metabolic changes and psychosis, we hypothesized that fatty liver may potentiate apomorphine-induced stereotypy in a rodent model and that a synthetic glucagon-like peptide-1 analog exenatide would ameliorate this effect. In this study, 18 male Sprague Dawley albino mature rats were used. We induced hepatosteatosis in these rats by feeding them with 30% fructose dissolved in drinking water for 8 weeks. The animals were divided into three groups, namely, the normal group, the intracerebroventricular (ICV) exenatide group, and the ICV NaCl group. Apomorphine-induced stereotypic behavior test was performed in all groups and the liver was removed for histopathological examination after all the rats were euthanized. In the nonalcoholic fatty liver (NAFL) group, stereotypy scores were significantly increased compared with the control group rats (p < 0.00001). A significant decrease in stereotypy scores were observed in the ICV exenatide group with NAFL when compared with the ICV saline group with NAFL (p < 0.005). In addition, brain malondialdehyde and tumor necrosis factor-α levels decreased in the ICV exenatide group. The results of this study showed that fatty liver enhances the effect of apomorphine on stereotypy, which was reversed by exenatide possibly by antioxidant and anti-inflammatory effects.  相似文献   
9.
Autism spectrum disorder (ASD) is commonly associated with reduced ability to recognize emotions in others. It is less clear however, whether ASD is also associated with impaired knowledge of one's own emotions. In the current study we present a first examination of how much knowledge individuals with ASD have about their emotions by investigating their ability to differentiate between emotions. Across two lab tasks that measured to what extent and how people differentiate between their own feeling states and semantic emotion terms, results showed that ASD individuals differentiated less than typically developing individuals. Yet, both groups of participants similarly categorized emotions according to previously established theoretical categories. These findings indicate that while both give similar meaning to emotions, individuals with ASD make less subtle distinctions between emotions. With low levels of emotion differentiation being linked to reduced well-being, these findings may help to better understand the high prevalence of internalizing problems associated with ASD.  相似文献   
10.
OBJECTIVE: To investigate the plasma homocysteine concentrations with regard to nutritional, metabolic and genetic factors and to find out the frequency and impact of thermolabile methylenetetrahydrofolate reductase (T-MTHFR) polymorphism in patients with type 2 diabetes mellitus. DESIGN: A cross-sectional study. SUBJECTS: A total of 94 subjects with type 2 diabetes mellitus and 91 healthy age- and sex-matched nonsmoking volunteers were recruited. MAIN OUTCOME MEASURES: Age, sex, duration and complications of diabetes mellitus, metabolic variables, fasting plasma homocysteine levels, and presence of T-MTHFR polymorphism were evaluated for all participants. Presence of T-MTHFR polymorphism was analysed to define any possible role in diabetes progress, complications and metabolic milieu. RESULTS: Fasting homocysteine levels were similar in diabetic patients and controls. Prevalence of homozygous polymorphism of thermolabile MTHFR gene (TT) was encountered more frequently in patients with diabetes mellitus than the healthy controls (P = 0.004). Subgrouping of the patients with respect to MTHFR genotype revealed similar metabolic variables and frequency of chronic complications of diabetes mellitus in groups. Patients with TT genotype revealed longer diabetes duration when compared with the patients having heterozygous mutation of thermolabile MTHFR or normal homozygous MTHFR genotypes (P = 0.046). CONCLUSIONS: Type 2 diabetic patients have similar fasting plasma homocysteine levels with that of age- and sex-matched healthy people. There is no correlation between diabetic complications and this amino acid metabolite. On the contrary, thermolabile variant of MTHFR genotype is found to be more frequent in diabetic patients especially in those who have experienced a longer duration of disease.  相似文献   
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