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31.
Purpose To develop a new mathematical model for calculating the volumetric wear of polyethylene cups from known values of the radius of the prosthesis head, the extent of linear wear and the direction of linear wear determined from standard antero-posterior radiographs.Method A new mathematical model was developed. The results of this new mathematical model were compared with the results obtained using the standard, frequently used mathematical model, which takes into consideration only the radius of the prosthesis head and the extent of linear wear of the polyethylene cups. The results of both mathematical models were further compared with the results obtained by direct measurement of volumetric wear using the fluid displacement method.Results Comparison of the mathematical models shows that the average volumetric wear calculated using the new mathematical model is 8.5% smaller than the average volumetric wear determined by the fluid displacement method, while the average volumetric wear calculated by standard mathematical model is 17.5% higher. The results of the new mathematical model are, thus, notably less biased than those of the standard one.Conclusion In calculating the volumetric wear from antero-posterior radiographs, not only the radius of the prosthesis head and the extent of the linear wear but also the direction of the latter has to be considered.  相似文献   
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The aim of the study was to assess the effect of prolonged action metoprolol on the microcirculation in patients with essential hypertension (EH). We studied 51 patients with EH aged 53,4+/-4,5 years. After 7-10 days of "wash-out" period and after 8 weeks of prolonged action metoprolol (betaloc ZOK) the state of microcirculation was investigated with the use of laser Doppler flux-metry (LDF). We found significant decrease in basically enlarged basal blood flow and the level of sympathetic activity, increase in the amplitude of cardiodependent waves, normalization of basal blood flow decrement in postural test, increase in capillary blood flow reserve in patients with stage I-II EH. We failed to observe any significant changes in the microcirculatory parameters in patients with stage III EH. Treatment with prolonged action metoprolol led to increase in the number of patients with normocirculatory type of microcirculation primarily due to the decrease in the prevalence of hyperemic type. We conclude that prolonged action metoprolol does not alter microcirculation in patients with EF. Moreover, at the early stages of EH it improves the functional state of peripheral hemodynamics due to suppression of sympathetic activity.  相似文献   
34.
Taftsin, an endogenous peptide immunostimulator, exhibits also high antiulcer activity. In a dose of 0.6 μmol/kg Taftsin decreases the area of ulcerative lesions in albino rats on various models of ulceration. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 8, pp. 185–187, August, 2004 This work was supported by the Russian Foundation for Basic Research (grant No. 03-04-48664).  相似文献   
35.
We studied the effect of potentiated antibodies against S-100 antigen on learning of avoidance responses of 2 types. Peroral administration of antibodies promoted inhibition of locomotor activity and feeding behavior, which was associated with electrical pain stimulation. Our results indicate that the preparation in ultralow doses modulates the mechanism of memory formation.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 12, pp. 629–631, December, 2004This revised version was published online in April 2005 with a corrected cover date.  相似文献   
36.
目的:探讨半夏泻心汤治疗幽门螺杆菌感染所致胃黏膜炎症的内在机制。方法:用幽门螺杆菌菌液给小鼠灌胃造模,然后随机分成10组,分别给予相应的药物治疗。观察各组小鼠胃黏膜的形态学改变及血清中NO和IL-8含量的变化。结果:模型组小鼠血清中NO、IL-8水平较空白组显著升高(P<0·01),各治疗组NO、IL-8水平均有不同程度的降低,其中以半夏泻心汤组、苦寒组、半夏加苦寒组、苦寒加甘温组降低最为显著,与模型组比较差异具有显著性意义(P<0·01)。结论:半夏泻心汤通过降低血清中NO、IL-8的含量而减轻胃黏膜的炎症反应,从而发挥其对胃黏膜的保护作用。  相似文献   
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The influence of extremely low frequency magnetic fields (ELF-MFs) on human physiological processes and, in particular, on motor activity is still not established with certainty. Using the wavelet-transform approach, changes in the characteristics of human finger micromovement are studied in the presence of a low intensity MF centred at the level of the head. Different approaches to nonstationary signal analysis involving real as well as complex wavelet functions are considered. We find evidence that ELF-MFs lead to more regular postural tremor and more homogeneous energy distribution.  相似文献   
39.
Objective: Massive hemorrhage is lifethreatening during armed conflicts. Tourniquets are important medical devices used to reduce severe bleeding in trauma. The aim of this study was to empirically evaluate the current tourniquets used in China and provide information to emergency nurses in selecting the appropriate tourniquet.Methods: Five tourniquets were self-applied by 20healthy participants. The blood flow distal to the tourniquet site was assessed using vascular Doppler ultrasound.Application time, pain, numbness, and other parameters were evaluated.Results: The bladder tourniquet and windlass tourniquet effectively occluded arterial blood flow with success rates higher than 75% in both the upper and lower extremities. The Cargo-strap was the fastest to apply, taking (7.22±2.30) s for the upper extremity and (6.48±2.40) s for the lower extremity. The rubber tube was the most painful, and the improvised tourniquet was the least efficient. The success rates were higher in the lower extremity than in the upper extremity (P<0.05, X2=5.714).Conclusions: The bladder tourniquet and the windlass tourniquet are efficient tourniquets, although the windlass is superior with respect to portability and pain. The Cargo-strap and rubber tourniquets have several disadvantages that reduce their suitability for field use. The improvised tourniquet is not recommended because of low efficiency and severe pain during implementation.  相似文献   
40.
Plantago ovata     
Plantago ovata is a high fibre bulk forming laxative. It absorbs water and expands to provide increased bulk and moisture content to the stool. The increased bulk encourages normal peristalsis and bowel motility. Clinical Indications: Constipation, Fecal Incontinence, Hemorrhoids, Ulcerative Colitis, Appetite, Hyperlipidemia, Diabetes mellitus.  相似文献   
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