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21.
During the last few years, telemedicine based on simple, low-cost technology has increased significantly in the Arkhangelsk region of north-west Russia. Specialists at the regional hospital of Arkhangelsk are diagnosing patients from local hospitals 600-700 km from the capital. A still-image system is used for emergency cases. The same technology, along with telephones with loudspeakers, is also used to provide distance learning at the regional hospitals of Arkhangelsk and Troms?. This article describes the results from the telemedicine collaboration between the University Hospital of Troms? and health-care institutions in Arkhangelsk, and discusses the experience gained.  相似文献   
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Experiments were conducted with CO2 and AIG laser on neodymium to study the condition of microcirculation and the degree of its disturbance in the wall of the small intestine in formation of a laser "welded" entero-enteral and termino-terminal anastomosis. The microcirculatory disorders and their extent were found to be directly dependent on the degree of the thermal effect and the width of the coagulation zone in the region of the suture. The results of the experiment confirmed that the suggested powers of the laser effect on the intestinal wall were optimal.  相似文献   
24.
A new method for treating acute pneumothorax with a bronchopleural fistula was experimentally developed and clinically tested. It is based on thoracoscopic use of CO2 laser radiation. The laser beam energy is employed for evaporation of necrotic tissues in the area of pulmonary destruction, "welding" of the bronchopulmonary fistulae, and general irradiation of the empyema cavity with a defocused beam. Nineteen patients with various disease duration were treated. In 16 patients the bronchial fistulae and the empyema cavity were eliminated and the lung re-expanded. The purulent inflammation in the pleural cavity was acute in these cases.  相似文献   
25.
To specify factors determining the intensity of uremic intoxication, 86 patients with chronic glomerulonephritis were examined without regard for exacerbation at different stages of chronic renal failure. Microcolumn gel chromatography was used to measure the content of medium-size molecules in the blood serum, urine, gastric and intestinal juice of the patients and 22 mongrel dogs before and after bilateral nephrectomy. It has been established that as the mass of acting nephrons decreases, the content of "medium-size" molecules in the blood serum and intestinal juice rises, being unchanged in gastric juice. At the same time the urinary clearance of the given group of substances declines. It is assumed that in stage I chronic renal failure, enhancement of the excretion of "medium-size" molecules in the proximal third of the small intestine is made for by hyperfiltration of intact nephrons. The appearance of the clinical symptomatology in stage II and III chronic renal failure is determined by intensification of absorption of uremic toxins by the intestine, associated with a fall of their urinary clearance. The necessity of early administration of the low-protein diet combined with enterosorbents is stressed.  相似文献   
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Despite the use of multimodal therapy, higher-grade glioma is stilluniformly fatal in the adult population. There is a considerable differencebetween the length of survival in each given patient, even within the sametumor type and malignancy grade group, suggesting that there are factorsthat might differentially influence outcome. To identify such factors, 107patients with anaplastic or malignant glioma were retrospectivelyinvestigated. Clinical parameters and paraclinical data on the p53, mdm2,and EGFR genes at the DNA or protein level were evaluated by univariateanalysis and Cox proportional hazards regression modeling. Kaplan-Meiersurvival estimation demonstrated that immunohistochemical positivity formdm2 protein in patients with anaplastic astrocytoma or with glioblastomamultiforme was associated with a shorter survival time (p = 0.02).P53 gene mutations and immunopositivity for the epidermal growth factorreceptor (EGFR) protein were not significantly related to poor prognosis.The Cox proportional hazards model revealed immunohistochemical positivityfor p53, mdm2, or for both of them, the presence of postoperativeirradiation, and the extent of surgical resection of tumor to be variablessignificantly associated with prolonged survival. EGFR overexpression, ageover 60 years, and Karnofsky performance score below 40 points did notsignificantly shorten survival time. In conclusion, the present studyidentified immunohistochemically detected mdm2-protein overexpression as astatistically significant negative prognostic parameter in patients bearinganaplastic or malignant glioma. Association analysis of variables revealed apossible correlation between mdm2 and p53, which is also consistent with thebiological interaction mode of both proteins in vivo.  相似文献   
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The study examined the effects of modulation of dopamine D2 receptors-mediated neurotransmission in the rat's prefrontal cortex (PFC) on storage and executive components of working memory. Rats were trained on delayed (delay interval, 3 s) and non-delayed choice in a U-maze. The prominence of proactive interference was evaluated by sorting errors in a current trial on the basis of animal reactions in a preceding trial. The erroneous runs to the same arm of the maze as in the previous trial were identified as the repetitions (RE) and the erroneous runs to the other arm in comparison with the previous trial were classified as alternations (AE). The bilateral microinfusion of D2 agonists PPHT (0.004 microg, 0.04 microg, 0.4 microg/1 microl) into medial wall of the PFC produced a dose-dependent increase in the error rate of the delayed-response task and did not influence non-delayed choice. In delay condition PPHT enhanced the perseverative tendencies (the rate of RE was significantly higher than the rate of AE), in non-delayed choice the erroneous performance was mainly represented by AE. In contrast, the infusion of D2-receptor antagonist sulpiride (0.03 microg, 0.3 microg, 3 microg/1 microl) increased the accuracy of delayed choice and changed the mode of intertrial dependence-rats made significantly more AE than RE. The results are discussed in terms of the involvement of D2 receptor dependent transmission of the PFC in different cognitive processes related to the delayed performance in U-maze (within-trial short-term storage of information versus dynamic control of between-trials working memory processing).  相似文献   
29.
This article is dedicated to investigating the properties of soil after its reinforcement with fiberglass elements through large-scale laboratory plate-load tests of various samples that varied in the numbers and lengths of the reinforcing elements. The investigation of the vertical elements considered the diameter increase at the bottom toe by using widening washers. The results were compared relative to each other and to the theoretical calculation results. The theoretical calculations for the settlements were undertaken based on the authors’ proposed method. The method considers the number, shape, area and material of the strengthening elements using a pre-proposed reinforcement area factor µ. This pre-established factor was calculated with reference to the elements’ geometry—the diameter of the vertical elements and the bottom’s washer diameter—which determined the reinforcement area. A comparison between the reinforced and reference soft sandy soil samples indicated a 25% increase in the deformation modulus after the reinforcement process at a pressure of 25 kPa. Samples with µ ranging from 1.20 to 1.43 were 55–65% stiffer than samples with µ equal to 0.69 at a pressure of 100 kPa. The comparative analysis of the calculated results and the actual laboratory PLT test results was adequate for use for further development.  相似文献   
30.
Concrete is the most widely used and most affordable construction material. The structural damage that concrete cracks and fractures may cause can be severe. These concerns have lately been alleviated by new developments in fibre concretes. Recent advancements in fibrous concrete and its evolution have been rapidly drawing researchers’ attentions worldwide, which motivates the development of a new type of composite with superior impact resistance. Preplaced aggregate fibrous concrete (PAFC) is a revolutionary composite comprising a higher dosage of fibres. It has outstanding impact resistance that surpasses those of traditional fibrous concrete. The impact behaviour of PAFC in addition to glass fibre mesh (GFM) has not been investigated thoroughly. To fill this research gap, this study investigates the impact performance of three-layered PAFC comprising steel fibres and GFM insertion. Eight different mixtures were prepared and can be divided into two groups. In the first group, specimens were made with 4% fibres and two single, double and triple layers of GFM insertion between the three-layered concrete. The second group of specimens was reinforced with 5, 2 and 5% steel fibres at the top, middle and bottom layers, respectively. However, the GFM insertion scheme for the second group was the same as the first. Rectangular specimens of size 500 × 100 × 100 mm were cast and tested against drop weight impact. The parameters studied were cracking impact numbers, failure impact number, ductility index and failure patterns. In addition, an analytical model was used to evaluate the impact failure energies. Results indicate that the combined action of steel fibre and GFM exhibited an excellent impact resistance. Increasing the number of GFM insertions between the specimen layer led to increased impact strength. The dose of the fibres utilized in the outer layer of the PAFC was increased, resulting in the material having a higher impact resistance. The cracking impact numbers improved from 28 to 40%, and failure impact numbers ranged from 58.8 to 92.2% when the GFM insertion numbers increased from one to three.  相似文献   
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