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V A Bukharin O A Makhachev Iu I Bondarev M A Nasedkina I N Mitina P A Chigochidze A A Reznikov 《Grudnaia khirurgiia (Moscow, Russia)》1989,(6):5-13
The article deals with the results of the study of the quantitative anatomy and morphology of hypoplastic ventricles. The object of study were 28 specimens of the heart: 15 with hypoplasia of the left ventricle and 13 with hypoplasia of the right ventricle. The control group was composed of 10 specimens of normal hearts. Morphometry was conducted in all of the 28 specimens. At the same time angiocardiometry and calculations of the volume characteristics of the ventricles were undertaken in the diagnosis of hypoplasia of the right ventricle. The morphometric criteria of hypoplasia of the heart ventricles and their morphological variants were determined as a result. It was found that the lineal characteristics of the heart yielded sufficient information both for the diagnosis of hypoplasia and for determining its degree. Morphometry showed that constant ratios exist between the diameters of the atrioventricular valves and the lineal sizes of the ventricles in normal and pathological hearts. Knowledge of the aforesaid is of much practical importance because having determined the sizes of the atrioventricular valves during echocardiography one may calculate all linear characteristics of the heart and evaluate the sizes of the ventricles by means of the quantitative criteria. The article gives the method of such calculation, while its results are evidence of the high precision of the suggested constants. 相似文献
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Oral opioid administration and hyperalgesia in patients with cancer or chronic nonmalignant pain 总被引:2,自引:0,他引:2
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AIMS: Previous research has reported on reduced paw withdrawal latencies to heat and mechanical stimuli after parenteral administration of opioids in animals and on increased pain sensitivity in humans subsequent to postoperative infusions of short-acting opioids or in drug addicts. The aim of the present study was to explore the possibility that oral opioid treated patients with cancer-related or chronic nonmalignant pain differ in their pain sensitivity from patients treated with non-opioid analgesics. METHODS: The study population consisted of 224 patients, including 142 in the opioid-treated group and 82 in the non-opioid-treated group. Pain thresholds for punctuate measured by von Frey filaments (g), mechanical pressure measured by pressure algometer (mmHg), heat stimuli measured by quantitative sensory testing (degrees C), as well as suprathreshold tonic heat pain intensity (46.5 degrees C for 1 min) measured by 0-10 numerical pain scale (NPS) were obtained at a nonpainful site (thenar eminence) in all patients. RESULTS: No differences between the groups were found for gender, age, duration of pain, or duration of treatment (independent variables). No significant differences between the groups were found in punctuate (difference = 17.0 g (95% CI -8.8, 42.8), P = 0.19), pressure (2.2 mmHg (-28.7, 33.2), P = 0.89) and heat (-0.3 degrees C (-1.5, 0.9), P = 0.70) pain thresholds, or in suprathreshold heat pain intensity (difference between maximal pain intensities -0.4 NPS units (95% CI -1.2, 0.4), P = 0.31). Pearson correlations within the opioid-treated group failed to show significant relationships between any of the independent variables and the outcome measures. A further comparison of the outcomes between the 'weak' opioid-treated subgroup and the 'strong' opioid-treated subgroup again revealed insignificant results. CONCLUSIONS: These results suggest that the administration of 'commonly used' dosages of oral opioids does not result in abnormal pain sensitivity beyond that of patients receiving non-opioid analgesia. 相似文献
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Sharon LR Kardia Reagan J Kelly Mehdi A Keddache Bruce J Aronow Gregory A Grabowski Harvey S Hahn Karen L Case Lynne E Wagoner Gerald W DornII Stephen B Liggett 《BMC medical genetics》2008,9(1):93
Background
Persistent stimulation of cardiac β1-adrenergic receptors by endogenous norepinephrine promotes heart failure progression. Polymorphisms of this gene are known to alter receptor function or expression, as are polymorphisms of the α2C-adrenergic receptor, which regulates norepinephrine release from cardiac presynaptic nerves. The purpose of this study was to investigate possible synergistic effects of polymorphisms of these two intronless genes (ADRB1 and ADRA2C, respectively) on the risk of death/transplant in heart failure patients. 相似文献99.
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Natalie Reznikov Carina Phillips Martyn Cooke Amin Garbout Farah Ahmed Molly M Stevens 《Journal of bone and mineral research》2017,32(9):1915-1925
The normal structure of human feet is optimized for shock dampening during walking and running. Foot binding was a historical practice in China aimed at restricting the growth of female feet for aesthetic reasons. In a bound foot the shock‐dampening function normally facilitated by the foot arches is withdrawn, resulting in the foot functioning as a rigid extension of the lower leg. An interesting question inspiring this study regards the nature of adaptation of the heel bone to this nonphysiological function using the parameters of cancellous bone anisotropy and 3D fabric topology and a novel intertrabecular angle (ITA) analysis. We found that the trabecular microarchitecture of the normal heel bone, but not of the bound foot, adapts to function by increased anisotropy and preferred orientation of trabeculae. The anisotropic texture in the normal heel bone consistently follows the physiological stress trajectories. However, in the bound foot heel bone the characteristic anisotropy pattern fails to develop, reflecting the lack of a normal biomechanical input. Moreover, the basic topological blueprint of cancellous bone investigated by the ITA method is nearly invariant in both normal and bound foot. These findings suggest that the anisotropic cancellous bone texture is an acquired characteristic that reflects recurrent loading conditions; conversely, an inadequate biomechanical input precludes the formation of anisotropic texture. This opens a long‐sought‐after possibility to reconstruct bone function from its form. The conserved topological parameters characterize the generic 3D fabric of cancellous bone, which is to a large extent independent of its adaptation to recurrent loading and perhaps determines the mechanical competence of trabecular bone regardless of its functional adaptation. © 2017 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc. 相似文献