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In vitro methods of testing the efficiency of barium sulphate suspensions in delineating mucosal detail using canine cadaveric stomachs have been described in the literature. In this study a comparison is made between in vitro and in vivo tests in the stomach and small intestine of dogs, using several brands of barium sulphate. The results indicate that there is considerable variation in the behavior of these suspensions between the in vitro and in vivo tests particularly in the stomach. It is our view that in vitro tests of this sort are of little value for assessing the relative advantages and disadvantages of these suspensions in demonstrating mucosal detail.  相似文献   
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The effects of 3 lipidosis-inducing drugs on the incorporation and turnover of palmitic acid-1-14C in lung phospholipids was studied. In rats treated with 1 dose of chlorphentermine or RMI 10.393, the incorporation of palmitate-1-14C into most lung phospholipid fractions was moderately decreased, but markedly lowered after 1 dose of Ro 4-4318. Eight doses of chlorphentermine and RMI 10.393 strongly inhibited the incorporation of palmitate-1-14C into lung phospholipids, whereas with 8 doses of Ro 4-4318 the incorporation was highly increased. Thirty hours after the last of 3 injections of the labeled palmitic acid the turnover of most lung phospholipids was considerably lower in chlorphentermine- and RMI 10.393-treated rats than in controls. Ro 4-4318, however, induced a highly increased turnover of most phospholipids. After 54 h, this effect had practically disappeared. Our studies showed that phospholipid storage after treatment with chlorphentermine and RMI 10.393 is mainly due to decreased degradation of phospholipids, whereas increased synthesis accounts for the effect of Ro 4-4318.  相似文献   
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Unilateral conditioned and indifferent acoustic stimuli were presented to dogs during the achievement of the unconditioned reflex to the stimulation of the contralateral side of the tongue. Formation of a backward temporary connection was observed with its typical features of a short manifestation of the effector reaction and of its rapid disappearance. A more stable backward connection was formed to previous positive conditioned stimuli, and a less stable one, to previously indifferent ones. It has been found that the elaboration of the backward connection as of a direct one, is attended with the formation of an excitation focus which contributes to a protracted manifestation of backward connections against the background of a contralateral excitation focus. The backward temporary connection, unlike the direct one, rapidly passes into a latent state in which it persists for a long time.  相似文献   
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BACKGROUND: Percutaneous mitral valvuloplasty with the Inoue balloon is conventionally performed with double vascular access: arterial and venous. However, in patients with a good echogenic window it may be performed with venous access only and the procedure monitored by 2D-echocardiography and colour flow mapping. This should result in early ambulation and hospital discharge with reduced arterial complications. AIMS: To compare retrospectively the immediate results of percutaneous mitral valvuloplasty with the Inoue balloon in two groups of patients: Group I: venous access only (no arterial access, n = 102) and Group II: conventional double vascular access (arterial and venous access, n = 275). METHODS AND RESULTS: The baseline characteristics of the two groups were comparable for age, sex, clinical, echocardiographic, radiological and haemodynamic variables. The mitral valve area (Group I: 1.1 +/- 0.3 to 1.85 +/- 0.5 cm2 vs Group II: 1.05 +/- 0.2 to 1.85 +/- 0.5 cm2, P = ns) and transmitral gradient (Group I: 11 +/- 4 to 4.7 +/- 2 mmHg vs Group II: 12 +/- 4 to 4.8 +/- 2 mmHg, P = ns) before and after mitral valvuloplasty were not statistically different. A good immediate result, defined as mitral valve area > 1.5 cm2 and mean mitral gradient < 5 mmHg with mitral regurgitation < or = 2+ at the end of the procedure, was observed in 77% of the cases in the venous-only group and 79% in the double access group (P = ns). The incidence of severe mitral regurgitation (Grade III or IV) was not statistically significant. Procedural duration (71 +/- 24 min vs 109 +/- 26 min, P < 0.01), fluoroscopic time (12.5 +/- 5.5 min vs 18.5 +/- 6 min, P < 0.01) and hospital stay (2.8 +/- 1.5 days vs 4.8 +/- 2.6 days, P < 0.001) were significantly shorter in the venous-only group than in the conventional Inoue series. CONCLUSION: Single venous access balloon mitral valvuloplasty is as equally safe and effective as double vascular access. The additional advantages of single venous access are shorter procedural duration, fluoroscopic time and hospital stay. We recommend that it be performed by an experienced operator (minimum of 100 trans-septal punctures) in patients without major thoracic deformity and a good echogenic window.  相似文献   
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Postinjury multiple organ failure: a bimodal phenomenon   总被引:1,自引:0,他引:1  
To better define the epidemiology of postinjury multiple organ failure (MOF), we prospectively evaluated 457 high-risk trauma patients who survived more than 48 hours. Overall, 70 (15%) developed MOF. In 27 (39%) patients, the occurrence was early, while in 43 (61%) patients the presentation was delayed. At presentation, early MOF had more cardiac dysfunction, while late MOF had greater hepatic failure. Indices of shock were more critical risk factors for early MOF, while advanced age was more important for late MOF. While early and late MOF had a similar high incidence of major infections, these appeared to be more important in precipitating late MOF. Finally, while mortality is similar, early MOF patients appear to succumb faster. In conclusion, postinjury MOF remains a significant challenge and appears to present in at least two patterns (i.e., early versus late). Better understanding of the relative roles of the dysfunctional inflammation and infections in early MOF versus late MOF may facilitate the development of new strategies for the prevention and treatment of morbid syndrome.  相似文献   
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