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971.
972.
A 65-year-old woman with chronic hypertension, chronic renal insufficiency, and schizophrenia self-discontinued her medications and presented complaining of decreased vision; she was found to have a blood pressure of 256/156 and visual acuity 20/70 OD. In the emergency department, her blood pressure was rapidly lowered to a nadir of 134/104. During the course of her hospitalization, her visual acuity declined from 20/70 to 20/200 OD in parallel with a decline in her renal function. Multi-modal imaging revealed simultaneous hypertensive retinopathy, choroidopathy, and optic neuropathy. Autofluorescence can play an important role in the diagnosis of hypertensive choroidopathy.  相似文献   
973.
Cancer and its treatment can lead in men to testosterone deficiency, accompanied by somatic and mental symptoms. Germ cell tumours and their treatment may disturb the pituitary–gonadal axis, hence leading to significant clinical abnormalities. In some prostate cancer patients, castration, temporary or permanent, is a desired therapeutic condition. Yet, it is burdened with various side effects of complex intensity and significance. Last but not least, patients in the terminal stage of a malignancy present with low testosterone concentrations as a part of anorexia–cachexia syndrome. Oncological management of such patients disturbs their homeostasis, androgen metabolism included, which results in numerous complications and worsens their quality of life. In the present paper, we analysed the frequency and sequelae of testosterone deficiency in some clinical scenarios, on the basis of original papers, meta-analyses and reviews available in PubMed. Androgen secretion disorders in male cancer patients depend on a cancer type, stage and methods of treatment. Number of testicular cancer survivors is increasing, and as a consequence, more patients cope with late complications, testosterone deficiency included. Hormone therapy in prostate cancer patients significantly prolongs survival, and then numerous men experience long-term adverse effects of androgen deficiency. Those, in turn, particularly the metabolic syndrome, may contribute to increased mortality. Androgen deficiency is a part of cancer anorexia–cachexia syndrome. The role of androgen deficiency in cancer patients is still under debate, and further studies are urgently needed to establish appropriate clinical guidelines.  相似文献   
974.
The article presents a comparative characterization of the structural materials (composites and metals) used in modern aviation structures, focusing on the airframe structure of the most modern aircraft (Airbus A-380, Boeing B-787, and JSF F-35). Selected design and operational problems were analysed, with particular emphasis on composites and light metals (aluminium). For this purpose, the Shore’s method was used for the analysis of the obtained strength results and the programming environment (ANSYS, SolidWorks) required to simulate the GLARE 3 2/1-04 composite. The focus was on highlighting the differences in the construction and modelling of these materials resulting from their various structures (isotropy and anisotropy), e.g., by analyzing the mechanics of metal destruction and comparing it with the composite material. In terms of solving the problems of finite element analysis FEM, tests have been carried out on two samples made of an aluminium alloy and a fiberglass composite. The focus was on highlighting the differences in the construction and modelling of these materials resulting from their various structures (isotropy and anisotropy), e.g., by analyzing the mechanics of metal destruction and comparing it with the composite material. On the basis of the obtained results, the preferred variant was selected, in terms of displacements, stresses, and deformations. In the final part of the work, based on the conducted literature analysis and the conducted research (analysis, simulations, and tests), significant observations and final conclusions, reflected in practical applications, were formulated.  相似文献   
975.
Objective: Asthma enhances the risk of pulmonary embolism. The mechanism of this phenomenon is unclear. Methods: We evaluated the kinetics of clot formation, clot retraction rate (CRR), clot volume at 40 min, the rate of lactate production (a marker of aerobic glycolysis in platelets in contracting clots), blood eosinophil count (EOS), nitric oxide in exhaled breath (FENO), and spirometry (FEV1) in 50 healthy controls and in 81 allergic asthmatics (41 subjects with steroid-naïve asthma and 40 with steroid-treated asthma). Results: Thromboelastometry revealed that only steroid-treated asthmatics had slightly activated coagulation. Compared with healthy controls, whole asthmatics demonstrated (p < 0.05) reduced CRR, higher clot volume at 40 minutes, higher FENO, decreased FEV1, elevated EOS, and augmented lactate production in retracting clots. Reduced CRR was observed also in the absence of native plasma. In whole study population (asthmatics and healthy controls), CRR positively correlated with spirometry (rS = 0.668, p = <0.001) and negatively with FENO (rS = ?0.543; p < 0.001), EOS (rS = ?0.367, p < 0.002), and lactate production (rS = ?0.791; p < 0.001). However, in steroid-treated asthmatics, the CRR did not correlate with FENO and EOS. In all study patients lactate production negatively correlated with FEV1 and positively with FENO. Conclusion: Collectively, this data is consistent with the hypothesis that, in asthmatics, reactive nitrogen species produced in the lungs may reduce platelet contractility (and CRR) through the diminution of platelet energy production. CRR inhibition would predispose asthmatics to pulmonary embolism.  相似文献   
976.
977.
The aim of the present study was to evaluate the validity of mixed anxiety and depressive disorder (MADD) with reference to functional characteristics and symptomatic characteristics in comparison with anxiety disorders, depressive disorders, and groups showing subthreshold symptoms (exclusively depressive or anxiety related). The present study was carried out in the following three medical settings: two psychiatric and one primary care. Patients seeking care in psychiatric institutions due to anxiety and depressive symptoms and attending primary medical settings for any reason were taken into account. A total of 104 patients (65 women and 39 men, mean age 41.1 years) were given a General Health Questionnaire (GHQ-30), Global Assessment of Functioning (GAF) and Present State Examination questionnaire, a part of Schedules for Clinical Assessment in Neuropsychiatry, Version 2.0. There were no statistically relevant differences between MADD and anxiety disorders in median GHQ score (19 vs 16) and median GAF score (median 68.5 vs 65). When considering depressive disorders the median GHQ score (28) was higher, and median GAF score (59) was lower than that in MADD. In groups with separated subthreshold anxiety or depressive symptoms, median GHQ scores (12) were lower and median GAF scores (75) were higher than that in MADD. The most frequent symptoms of MADD are symptoms of generalized anxiety disorder (GAD) and depression. Mixed anxiety and depressive disorder differs significantly from GAD only in higher rates of depressed mood and lower rates of somatic anxiety symptoms. Distinction from depression was clearer; six of 10 depressive symptoms are more minor in severity in MADD than in the case of depression. Distress and interference with personal functions in MADD are similar to that of other anxiety disorders. A pattern of MADD symptoms locates this disorder between depression and GAD.  相似文献   
978.
979.

Background

Cases of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are increasing in the pediatric population. Their growing prevalence coincides with the obesity epidemic. Assessment of the incidence requires liver biopsies on a representative population sample, which are hampered by the absence of indications for invasive examination on children without clinical symptoms. The aim of the current study was to assess the incidence of liver steatosis in the population of children up to 18 years old from Lower Silesia.

Methods

We retrospectively reviewed 342 medico-legal autopsy reports from 2000 to 2009. We separated a group of 256 children whose death was caused by trauma. Liver steatosis was diagnosed according to the results of histopathological examinations and typical macroscopic imaging.

Results

In the 265 children who died from trauma, liver steatosis was reported in 11 (4.2%) children (6 boys) aged between 6 months and 18 years old. Six of the 11 children (54.5%) were found to be overweight. In all 342 children, steatosis was found in 18 (5.3%) children (13 boys), while NASH was diagnosed in 1 (0.3%). Excess body weight was observed in 55.6% (10/18) of children with steatosis.

Conclusions

Liver steatosis can occur at any age, even in infancy. Being overweight is a very important risk factor. Gross examination of the liver is insufficient for the diagnosis of steatosis because of its lower sensitivity and specificity. Verification of liver steatosis requires reference histopathological examination.  相似文献   
980.
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