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101.
Young patients with symptoms of anterior knee discomfort represent a most difficult and often enigmatic clinical group, in large part because of the highly subjective nature of the condition. A primary clinical research goal over the past several years has been a search for reliable objective indicators of a presumed underlying pathologic process to account for the symptoms. We believe that the use of the bone scan along with other clinical and experimental data has provided a new and previously unappreciated perspective of a dynamic osseous process occurring in many such patients. With further investigation, this process may clarify certain confusing aspects of the symptoms experienced by patients with patellofemoral pain. The technique and its clinical applications are still in its infancy, yet it appears to hold promise for the future. It is hoped that exposure to this method of evaluation will serve as a basis for an understanding of the benefits, limitations, and implications of this technique as further developments occur.  相似文献   
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The application of segmented 3D gradient echo EPI at 0.5 T for coronary artery imaging is described. Experiments were performed using fat suppression, ECG triggering, and a patient-controlled breath-holding scheme. This approach provides a sufficient signal-to-noise ratio for thin contiguous slices in conjunction with a phased array cardiac receive coil. Wide 3D volumes, covering the proximal branches of the coronary tree, were measured with a high spatial resolution. Such data sets can be used for subsequent vessel segmentation. Furthermore, data out of narrow 3D volumes were obtained containing fewer slices angulated in the direction of a selected coronary artery. This provides a good visualization of the selected vessel over several centimeters without the need for segmentation.  相似文献   
104.
As cardiac transplantation has become widely available, computed tomography (CT) of the chest has played a useful role in the examination of patients after heart transplantation. To determine anatomic features related to the procedure, the authors evaluated 59 scans in 46 patients who had undergone orthotopic cardiac transplantation. Aortic anastomosis (seen in 98% of scans) and altered spacing between the great vessels (83%) proved to be the most common and most reliable findings. Other features including atrial anastomosis, high main pulmonary artery segment, remnant superior vena cava, and cardiac reorientation were also seen. Accurate interpretation of adenopathy, mediastinal abscess, and pericardial effusion will be enhanced in these patients through a better understanding of the cardiovascular-pericardial complex, which is afforded by CT.  相似文献   
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BACKGROUND: Pantoprazole is a substituted benzimidazole which is a potent inhibitor of gastric acid secretion by its action upon H+, K+- ATPase. METHODS: Pantoprazole 40 mg and 80 mg were compared in a randomized double-blind study in 192 out-patients with stage II or III (Savary-Miller classification) reflux oesophagitis. Patients received either pantoprazole 40 mg (n = 97) or pantoprazole 80 mg (n = 95), once daily before breakfast for 4 weeks. Treatment was extended for a further 4 weeks if the oesophagitis had not healed. RESULTS: After 4 weeks complete healing of the reflux oesophagitis was seen in 78% of protocol-correct patients given pantoprazole 40 mg daily (n = 86), and in 72% in the 80 mg (n = 87) group. The cumulative healing rates after 8 weeks were 95 and 94%, respectively (P > 0.05, Cochran-Mantel- Haenszel), and time until healing of oesophagitis comparable in both groups. Differences between doses were also not significant in an intention-to-treat analysis. Both dosing schedules were well tolerated and the patients experienced remarkable symptom relief. No adverse event or changes in laboratory values of clinical significance could definitely be ascribed to the trial medication. CONCLUSION: The 40 mg pantoprazole dosage is comparable to 80 mg in reflux oesophagitis, both in efficacy and tolerability.  相似文献   
107.
Earthquakes, influenza and cycles of Indian kala-azar   总被引:1,自引:0,他引:1  
It is suggested that previous data indicate 3 major epidemics of kala-azar in Assam between 1875 and 1950, with inter-epidemic periods of 30-45 and 20 years. This deviates from the popular view of regular cycles with a 10-20 year period. A deterministic mathematical model of kala-azar is used to find the simplest explanation for the timing of the 3 epidemics, paying particular attention to the role of extrinsic (drugs, natural disasters, other infectious diseases) versus intrinsic (host and vector dynamics, birth and death rates, immunity) processes in provoking the second. We conclude that, whilst widespread influenza in 1918-1919 may have magnified the second epidemic, intrinsic population processes provide the simplest explanation for its timing and synchrony throughout Assam. The model also shows that the second inter-epidemic period is expected to be shorter than the first, even in the absence of extrinsic agents, and highlights the importance of a small fraction of patients becoming chronically infectious (with post kala-azar dermal leishmaniasis) after treatment during an epidemic.  相似文献   
108.
Traditional operations to obstruct the IVC are often unsatisfactory because the morbidity and mortality is appreciable: poor risk patients do not tolerate surgical and anesthetic trauma. Furthermore, if the patient is anticoagulated, an operation requires that such desirable treatment be stopped. Ten years ago a study was begun to develop a transvenous method of IVC occlusion in the awake anticoagulated patient. Animal studies were done prior to patient application. A technique was evolved wherein IVC interruption could be accomplished with a balloon bearing catheter inserted through the jugular vein. The balloon was positioned with venography and after inflation held in place by lateral pressure in the distensible IVC. The catheter was then removed, leaving the balloon in position. Balloon occlusion has been used in the management of 60 selected patients since 1970. Twenty-nine patients were simultaneously anticoagulated without complication. Very sick patients tolerated the procedure well. No patient experienced further pulmonary emboli. Nine hospital deaths occurred from a variety of causes, none related to the balloon catheter. Late follow-up shows that the occluding balloon gradually deflates in about 12 months. The remnant has remained stable in all patients, contained in a scar that permanently interrupts the IVC.  相似文献   
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