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1. The cells of the cortex of the posterior bank of the superior temporal sulcus of the monkey appear to be specialized to signal motion in the visual field. In this paper, cells in this cortical area capable of signalling motion towards or away from the animal are described.2. Two such types of cell were encountered. One type, the opposed movement complex and opposed movement hypercomplex cells, responded to two edges at a given orientation moving towards or away from each other within the receptive fields. These cells were driven either monocularly or binocularly, but when binocularly driven the cells responded in an identical manner to stimulation of each eye, thus suggesting that such cells must receive a double, and opposed, input from each eye. The other type of cell, always binocularly driven, responded to movement in opposite directions on the two retinas, thus suggesting that such cells must receive diametrically opposite connexions from the two eyes.3. Long penetrations made to study the manner in which such cells were grouped together in the cortex revealed that they were arranged in small groups or clusters, separated from each other by the common directionally selective cells so prominently present in this area. Thus, cells with one type of wiring mechanism were separated from each other by cells receiving another, and more common, type of anatomical wiring.  相似文献   
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Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model.  相似文献   
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BackgroundThis study investigated the relationship between coronary collateral circulation (CCC) and intracoronary thrombus burden in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction (STEMI). CCC and thrombus burden are predictive of clinical outcomes in patients with STEMI.MethodsPatients with STEMI undergoing primary percutaneous coronary intervention were enrolled (n = 172). CCC was graded according to the Cohen–Rentrop classification. Patients were classified as insufficient (grade 0 or 1, n = 134) or well-developed (grade 2 or 3; n = 38) CCC. The Thrombolysis in Myocardial Infarction scale was used to evaluate intra-coronary thrombus burden. The low-thrombus-burden group comprised those with grades 0 to 2, and the high-thrombus-burden group comprised those with grades 3 or 4.ResultsRight coronary artery infarcts had a 13.830-fold higher chance of having well-developed CCC than did left anterior descending artery infarcts (P < .001). Circumflex artery infarcts had a 7.904-fold higher chance of well-developed CCC than did left anterior descending artery infarcts (P = .016). High thrombus burden was associated with a 4.393-fold higher chance for well-developed CCC than was low thrombus burden (P = .030). Low albumin levels were related to a greater chance of having well-developed CCC (P = .046).ConclusionPatients with well-developed CCC have higher thrombus burden than do those with insufficient CCC. Because well-developed CCC is an indicator of more severe underlying lesions, we speculate that patients with severe lesions are more prone to experience more complicated STEMI with high thrombus burden.  相似文献   
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BackgroundAbdominal aortic aneurysm (AAA) has risk factors similar to those of atherosclerosis. Salusin-β and arterial stiffness are novel parameters that have been shown to predict atherosclerosis and related cardiovascular disorders. However, their predictive value for detecting AAA remains unclear.MethodsForty-eight patients with AAA and 47 age- and sex-matched participants without AAA were enrolled in the study. Arterial stiffness parameters were obtained via an oscillometric Mobil-O-Graph PWA Monitor device (IEM GmbH) with integrated ARCSolver software (Australian Institute of Technology). Plasma salusin-β levels were analyzed using an enzyme-linked immunosorbent assay reagent kit (Abbkine, Inc). The measured salusin-β levels and arterial stiffness parameters of the AAA and control groups were compared.ResultsSalusin-β levels were significantly lower in patients with AAA (P = .014). There was a significant negative correlation between salusin-β levels and abdominal aorta diameter. No significant difference was detected between AAA and control groups in terms of arterial stiffness parameters (P > .05). In backward multiple regression analysis, the presence of AAA, platelet count, and augmentation index were found to be independent predictors of salusin-β levels (P = .006 and P = .023, respectively).ConclusionArterial stiffness parameters were not found to be associated with AAA. Contrary to previous results regarding atherosclerosis and related cardiovascular disorders, salusin-β levels were found to be lower in patients with AAA. Although AAA is thought to have similar risk factors as atherosclerosis, the exact pathophysiologic mechanism remains unclear.  相似文献   
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BACKGROUND: Helicobacter pylori eradication rates have tended to decrease recently possibly related with increasing antibiotic resistance. The present study investigated the efficacy of three different ranitidine bismuth citrate (RBC) based triple regimens in a population with high prevalence of H. pylori. METHODS: 300 consecutive H. pylori positive patients with non-ulcer dyspepsia were randomized into three regimens: (1) RBC 400 mg, amoxicillin 1000 mg and tetracycline 500 mg [RBC-AT], (2) RBC 400 mg, amoxicillin 1000 mg and clarithromycin 500 mg [RBC-AC], (3) RBC 400 mg, metronidazole 500 mg and tetracycline 500 mg [RBC-MT]. Tetracycline was given q.i.d, all other drugs were given b.i.d. for 14 days. Gastroscopy and (14)C-Urea breath test (UBT) were performed before enrollment and UBT only was repeated 6 weeks after the end of treatment. RESULTS: 274 patients completed the protocols. The overall 'intention to treat' and 'per protocol' H. pylori eradication rates in all subjects were 57.6% (95% CI: 52-63) and 63.1% (95% CI: 57-68), respectively. The eradication rates achieved in the groups (RBC-AT, RBC-AC and RBC-MT) were 64.4% (95% CI: 54-74), 66.2% (95% CI: 56-76), and 58.9% (95% CI: 49-68) on 'per protocol' analyses, respectively. There was no difference in eradication rates, compliance and major side effects between the groups. CONCLUSION: The current RBC-based H. pylori eradication therapy is not adequately effective.  相似文献   
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OBJECTIVE: Thoracic impedance cardiography (TIC) is a noninvasive method which has proved to be useful in monitoring the haemodynamic status of the patients. In this study, we evaluated the TIC findings in patients with pericardial effusion and cardiac tamponade. METHODS AND RESULTS: The study consisted of patients with pericardial effusion with (group A) or without (group B) cardiac tamponade (CT). The stroke volume, cardiac output and ejection fraction was measured by both echocardiography and TIC. The measurements were done at baseline in both groups and following pericardiocentesis in group A. The variables were compared by linear regression analysis, paired sample's t test and chi-square test. The study included 32 patients. Group A consisted of 16 patients and group B of 14 patients. Two patients were excluded from comparisons because of insufficient quality of the echocardiographic examination. There were no significant differences between group A and B with regard to demographic features. Both echocardiographic and TIC measurements at baseline revealed decreased cardiac output, EDV and SV in group A and EF was not different. Linear regression analysis revealed that echocardiography and TIC were in significant correlation with regard to cardiac output, enddiastolic volume, stroke volume (p < 0.01) but not ejection fraction (p = 0.8910). The correlation was also present after pericardiocentesis. CONCLUSIONS: TIC can be safely used in patients with pericardial effusion. It provides suggestive data for the diagnosis of CT and can be used as a means of monitoring the results of the pericardiocentesis.  相似文献   
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