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81.
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus. 相似文献
82.
83.
The prognostic value of A, B, H blood group antigen determination in superficial bladder cancer is unclear. Recent immunohistochemical studies employing monoclonal antibodies and Ulex Europaeus Agglutinin I (UEA-I) (Vector) have shown that A, B, H detectability and distribution in non-neoplastic urothelium are influenced by methodologic factors and, most importantly, by the secretor status. The authors investigated the A, B, H antigen in 93 tumors of the urinary bladder (78 secretors, 15 nonsecretors) and semiquantified the alterations from the expected normal expression on a scale from 0 to 3. Four O saliva nonsecretors as expected showed no staining and were excluded. Eighty tumors showed abnormal A, B, H expression and in 37 of these, A, B, H antigens were not detected. Tumors of A and O individuals showed statistically different reactivities, probably related to differences in the specificity of the employed A- and H-reagents. A, B, H expression was influenced by stage and grade (P less than 0.05, P less than 0.10) and was correlated to the clinical course of A but not O patients. These results, suggesting that alterations in the A, B, H expression occur early in the neoplastic development and follow the synthetic pathways in an opposite direction, emphasize that reagents recognizing blood group precursor substances, common to all individuals irrespective of the ABO and saliva secretor types, may increase the prognostic accuracy of blood group antigen determination in bladder cancer. 相似文献
84.
Y H Juhl 《American journal of hospital pharmacy》1986,43(1):98-102
The stability of prednisone tablets that had been stored in hospitals across the United States was studied. Through a voluntary FDA drug stability program, all hospital pharmacies in the United States were asked in October 1982 to complete a response card indicating information about prednisone tablets they had in stock. Based on the responses, FDA selected 117 samples (representing 18 manufacturers and all available tablet strengths) from pharmacies that represented an adequate cross section of the country. The samples were analyzed for content uniformity, strength, identification, dissolution, and the presence of other steroids. All samples met USP requirements for content uniformity and strength. Four samples failed to meet USP requirements for dissolution. Prednisone tablets appear to be stable when stored under actual marketplace conditions. 相似文献
85.
Effects of Progressive Hypoventilation on Left Ventricular Appearance: An Alternative Etiology of Acute Sonographic Short‐Axis D‐Shaping
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87.
Abstract Objectives. The management of sternal defects arisen after deep sternal wound infection is challenging and often requires extensive interdisciplinary teamwork between plastic and thoracic surgeons. In this study, the published literature on methods used to reconstruct sternal defects arisen as a result of deep sternal wound infection after open-heart surgery will be reviewed. Design. The Cochrane, Embase, PubMed, and SveMed + databases were searched in December 2011. Only papers regarding treatment of deep sternal wound infection after open-heart surgery in adults were included. Results. The literature search identified 224 original papers that met the inclusion criteria. The majority dealt with surgical techniques. None of the studies regarding reconstructive options were designed as randomized controlled trials, and the levels of evidence are generally low. Conclusion. The treatment of deep sternal wound infection has evolved considerably, but there is still little consensus regarding optimal surgical management and a general lack of a standard treatment protocol. The use of muscle flap transposition is well documented. Recent studies recommend the use of topical negative pressure therapy as an adjunct to surgical reconstruction. 相似文献
88.
A Malchow-M?ller C Thomsen J Hilden P Matzen L Mindehom E Juhl 《Scandinavian journal of gastroenterology》1985,20(2):155-162
A consecutive series of 1002 jaundiced adult patients covering 23 different causes of jaundice is presented. Patients were followed up for 2 to 7 years. The survival for the 784 patients included during their first episode of jaundice was calculated for each diagnostic category. Examples of decreased survival as compared with the general population were (figures indicate 3 months' and 5 years' survival, respectively): alcoholic cirrhosis 0.81, 0.35; cryptogenic cirrhosis 0.78, 0.32; pancreatic carcinoma 0.54, 0.04; cholangiocarcinoma 0.26, 0.00; and heart failure with liver congestion 0.47, 0.07. Ten of 172 patients with acute viral hepatitis died, 1 of fulminant hepatitis and 9 because of suicide or accidents. Of 105 patients with gallstones 37 died during the study period, but in only 9 of these could death be attributed to the gallstone disease. New diagnostic methods and types of treatment for jaundiced patients have been developed during recent years. To justify fully these diagnostic and therapeutic modalities, knowledge of the prognosis for the various causes of jaundice is essential. 相似文献
89.
90.
Six human hematopoetic cell lines were successfully heterotransplanted into athymic (nude) and asplenic-athymic (lasat) neonatal mice. The tumors arising from leukemia and lymphoma cells could then be serially transplanted into adult nude mice. Seven days after the fourth serial mouse passage, each mouse was treated with goat immune gamma globulin against K-562 cells. One control group was treated similarly, but with nonimmune (normal) gamma globulin, while another control group was not treated. The goat gamma globulin was not toxic for nude and lasat mice, and the immune, but not the normal, gamma globulin suppressed local subcutaneous growth of myelosarcomas, lymphosarcomas, and Burkitt lymphoma cells. On the other hand, the growth of lung, breast, and prostatic carcinomas and a melanoma of human origin were not altered by the immune gamma globulin. Since suppression of cell growth occurred equally well in decomplemented mice, a complement-mediated cytotoxicity apparently cannot be considered as responsible for the abrogation. The Fab fragment of the immunoglobulin did not suppress the growth of the myelosarcomas. We conclude that antibody suppression of the in vivo proliferation was specific for malignant hematopoietic cells and that the Fc portion of IgG is necessary for in vivo cytolysis of leukemia cells. The most probable mechanisms are direct antibody cytolysis and antibody-dependent macrophage-mediated cytotoxicity. 相似文献