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31.
A 49-year-old man underwent transthoracic echocardiography for atypical chest pain. A dilated coronary sinus was found and venous contrast echocardiography raised the suspicion of absent right and persistent left superior vena cava. Transesophageal echocardiography showed no presence of right superior vena cava. The echocardiographic findings were confirmed by upper venous digital subtraction cavography.  相似文献   
32.
We analyse the improving role of teaching microsurgery, the advantages of the microsurgical models in research and clinical practice. We summarize our experience in teaching basic microsurgery according to Furka's model in the last 15 years. The main characteristics of the principles are: activity, synchronism, video assistance, self-control, individualization, analysis. We show the curriculum of the courses for researchers and participants in graduate and postgraduate education, which consists dry-training on models followed by surgical interventions on rats. Summarizing of our practices: to learn the basic microsurgical techniques the participants need endurance, patience, and have to work hard. Effectiveness of the education is most successful if we organize small groups, if one teacher deals with a maximum of two or three candidates.  相似文献   
33.
Researches of different spleen salvaging techniques have begun in 1986 at our department. The early purpose was to develop new spleen preservation surgical techniques, such as spleen autotransplantation and spleen resection. Besides the morphological and radiological examinations we also performed different investigations including hemorheological, hemostaseological and immunological follow-up of the splenic function. From these parameters changes in red blood cell deformability and peripheral phagocyte activity could indicate the possible complications originated from the reduced splenic function. Recent paper takes a survey of these experiences.  相似文献   
34.
INTRODUCTION: Disorders around the patella are the most frequent knee complaints seen in adolescents. In the literature many intrinsic and extrinsic risk factors have been linked to Patellofemoral Pain Syndrome (PFPS), but the role of these risk factors is controversial. AIM: The goal of this study was to evaluate the prevalence of PFPS in a group of adolescents aged 12-20 years in Hungary, and to gain more information on the relationship between the biomechanical anomalies of the lower extremity and the PFPS. MATERIAL AND METHODS: In this epidemiological study the authors investigated the effect of sporting activity in the maturation of symptoms among 586 randomly selected students. Different physical examinations, anthropometric measurements, stability tests, footscan analysis were performed. RESULTS: Concerning the prevalence of this syndrome they could not find any differences between males (n = 60, 20.41%) and females (n = 61, 20.89%). The authors could not identify any statistically significant intrinsic risk factors, although changes in the Q angle may be linked to increased prevalence of PFPS. The study supports the theory of the importance of "overload", for there was a significant correlation between the prevalence of PFPS and the different levels of sporting activities (competitive, recreational and non-athletes). CONCLUSION: The authors concluded that the prevalence of PFPS among Hungarian students is 20.65%.  相似文献   
35.
The current status in rational drug design using homology-based models is discussed, with focus on template selection, model building, model verification and strategies for drug design based on model structures. A novel approach for identification of unique binding site features from homology-based models, Protein Alpha Shape Similarity Analysis (PASSA) is described.  相似文献   
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Distribution, chemical-neuroanatomy, concentration, and uptake-release properties of histamine (HA)-containing neurons and the possible physiological effects of HA in the central and peripheral nervous system of the pulmonate snails, Helix pomatia and Lymnaea stagnalis, are described. In the CNS of both species, the distribution pattern of HA-immunoreactive (HA-IR) neurons was similar. In both species the majority were located in the buccal, cerebral, and pedal ganglia. In Helix, approximately 400 HA-IR neurons were seen, whereas in Lymnaea approximately 130 labeled cells were visualized. The neuropils, connectives, commissures, several peripheral nerves, and a part of the peripheral tissues (lip and foot of both species and the upper tentacles of Helix) were innervated by HA-IR elements. Numerous sensory cells were found in the tentacles, lip, and statocysts. The HA concentration values assayed by HPLC ranged from 4.8 to 47.4 pmol/mg in the different central ganglia of Helix, and from 4.3 to 18.6 pmol/mg in Lymnaea CNS, whereas the peripheral tissues contained 0.33-1 pmol/mg HA in Helix and 0.26-0.46 pmol/mg in Lymnaea. In the Lymnaea CNS, a high-affinity (37.6 microM), single component 3H-HA uptake system was demonstrated. 3H-HA release evoked by either electrical stimulation or 100 mM K+ could be prevented in Ca2+-free physiological solution. Voltage-clamp experiments indicated specific changes caused by HA in the membrane conductance of identified central neurons of Helix and Lymnaea. Exogenously applied 10(-5) M HA resulted in the acceleration of locomotion (gliding by foot cilia) of Lymnaea. The findings suggest an important signaling role of HA, described here for the first time, in the nervous system of higher-order, pulmonate, gastropods, involving efferent, integrative, and sensory functions. The data can also be applied as a background for further specification of HA in the regulation of different behaviors in these species.  相似文献   
38.
OBJECTIVE: To test electric field stimulation on human placental vessels. METHODS: The effects of electric field stimulation on placental vessels were examined in an isometric myograph. RESULTS: Electric field stimulation induced contractions in human placental blood vessels in vitro under isometric conditions when bubbling carbogen through the organ bath. After reaching half-maximal contractions, the vessel rings showed spontaneous relaxation. Pretreatment with verapamil (10(-6) mol/L) or nickel (Ni(2+)) (2 mmol/L) inhibited the contractions to a magnitude of 63.81% +/- 7.69% and 88.36% +/- 12.17% (mean +/- standard error of the mean), respectively. In calcium (Ca(2+))-free medium after combined cyclopiazonic acid (10(-5) mol/L) and Ni(2+) treatment, it was not possible to elicit contractions with electric field stimulation. Bubbling through physiologic in utero hypoxic gases enhanced the contractile responses of the human placental vessel rings to electric field stimulation. The spontaneous relaxation of the veins was not altered, but those of the arteries were reduced to zero. Testing the same gases on mesenteric arteries of rats had an opposite effect concerning contractility. Sodium nitrite decreased the contractions of the placental vessel rings, but the efficacy was decreased by the in utero gases. CONCLUSION: Electric field stimulation has a direct, non-neurogenic contractile effect on isolated placental vessels, which mainly depends on the influx of extracellular Ca(2+) and on a mechanism independent of intracellular Ca(2+) concentration elevation. Physiologic hypoxia has a stimulatory effect on the contractility of human placental vessels, therefore in utero gases should be used instead of carbogen gas; and electric field stimulation is a suitable method for the investigation of the direct effects of pharmacologic agents on human placental vessels.  相似文献   
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We report the first case of pulmonary tuberculosis caused by Mycobacterium bovis subsp. caprae in a captive Siberian tiger, an endangered feline. The pathogen was isolated from a tracheal aspirate obtained by bronchoscopy. This procedure provided a reliable in vivo diagnostic method in conjunction with conventional and molecular tests for the detection of mycobacteria.  相似文献   
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