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451.
BACKGROUND: Extracellular types (high-Na) of cold-storage solution (CSS) have been shown to be more effective in preserving kidneys than intracellular CSS (high-K). On the other hand, calcium entry blockers (CEB) have been demonstrated to improve graft function when administered after and/or prior to transplantation. The ischaemia reperfusion syndrome involves, in part, an alteration in intracellular calcium metabolism that induces an increase in renal vascular resistances (RVR) and other cellular dysfunction, and high-K CSS per se are vasoconstrictive. Since CEB act via a modification in intracellular calcium metabolism on vascular smooth muscle, glomerular, and tubular cells, we evaluated the actual benefit on CEB on kidneys preserved in Belzer's CSS (K-UW) and a high-Na version of Belzer's CSS (Na-UW). METHOD: The isolated perfused rat kidney (IPK) was used, first as a vascular bed to test the effects of CSS on RVR, and the influence of nifedipine. Second, the recovery function of the IPK was assessed by GFR and tubular Na reabsorption, after 24 h preservation in K-UW and Na- UW, with or without nifedipine. Results were compared with a control group in which renal function was measured without prior cold-storage. RESULTS: K-UW but not Na-UW induced an increase in RVR when flushed into the kidney. This vasoconstriction is prevented by nifedipine. K-UW CSS was more deleterious to renal function than Na-UW. Addition of nifedipine to the flush, the CSS for 24 h, and to the normothermic reperfusate further improved recovery function of the IPK cold stored in Na-UW but not in K-UW, without any modification of RVR. CONCLUSION: Nifedipine may be of potential effect in attenuating ischaemic injury by a mechanism which does not involve its vasodilatory properties.   相似文献   
452.
Twenty-six pleural biopsies were performed on 23 patients over a 3-year period. Twenty-three biopsies were performed guided with ultrasound; one, with computed tomography; and two, with fluoroscopy. Indications for an image-guided pleural biopsy were (a) pleural masses or thickening that were either not seen on chest radiographs or seen only on one view and (b) small or loculated pleural effusions of unknown cause with no mass seen. If only pleural fluid was present, reverse bevel needles were used for biopsy (n = 15). If a discrete pleural mass or thickening was seen with cross-sectional imaging, standard (16-20 gauge) biopsy needles were used (n = 11). In the 23 patients, biopsy results were true positive in ten (nine with malignancy, one with tuberculous pleurisy), true negative in ten (confirmed either at subsequent thoracotomy or clinical follow-up), and false negative in three. Complications were few, with a significant pneumothorax occurring in two patients (8.7%). Image-guided biopsy of small pleural lesions and small pleural effusions can be performed by the radiologist who understands the special needles and techniques involved.  相似文献   
453.
454.
为了寻求在较好地保持酶活力的同时解除L-天冬酰胺酶抗原性的方法,采用不同分子量的乙酸酐、右旋糖酐和单甲氧基聚乙二醇,作为修饰剂和不同的修饰方法对该酶进行了化学修饰。结果表明在保持酶活性和降低抗原性方面,大分子修饰剂右旋糖酐、单甲氧基聚乙二醇优于小分子乙酸酐,底物保护修饰优于直接修饰;活化PEG,优于活化PEG1。在底物保护下的PEG,修饰酶其抗原性完全解除的同时,酶活力保持在30%以上。  相似文献   
455.
Stevens  SK; Moore  SG; Amylon  MD 《Radiology》1990,175(1):213-218
Sixty-seven magnetic resonance (MR) studies of the lumbar spine were performed in 15 patients with bone marrow transplants, and the appearance of marrow regeneration on MR images was correlated with results of bone marrow biopsy and pathologic examination. After transplantation, T1-weighted MR images of vertebral marrow showed a characteristic band pattern consisting of a peripheral zone of intermediate signal intensity and a central zone of bright signal intensity. Reciprocal changes were identified on short inversion time inversion recovery images. At histologic examination the central zone corresponded to fatty marrow; the peripheral zone corresponded to a zone of regenerating hematopoietic cells. Posttransplantation T1 and T2 relaxation times of the entire vertebral marrow were calculated from the spin-echo images; no statistically significant trends in relaxation times were noted. Knowledge of the normal MR pattern of marrow regeneration after transplantation may be useful in screening for residual marrow disease, determining marrow engraftment, and differentiating marrow repopulation with normal versus malignant cells.  相似文献   
456.
Plasma proteins and lymphocyte phenotypes in long-term plasma donors   总被引:2,自引:0,他引:2  
BACKGROUND: The possible effects of long-term plasma donation remain unknown, but it is important to investigate them so that donor safety is ensured. The purpose of this study was to determine if long-term plasma donation alters plasma proteins or lymphocyte phenotypes. STUDY DESIGN AND METHODS: Two groups of long-term plasma donors, source plasma donors (n = 20) and Rh immune globulin plasma donors (n = 26), were compared with whole blood donors (n = 29) and nondonor controls (n = 30). Blood samples were obtained prior to donation. Serum protein, albumin, globulin, and immunoglobulin levels were determined. In an assay using whole blood, lymphocyte phenotypes were characterized with a panel of single- and dual-labeled monoclonal antibodies and subsequent analysis by flow cytometry. RESULTS: As compared to the nondonor controls and/or whole blood donors, the mean values for serum protein, globulin, and IgG levels were lower in both plasma donor groups, with a significant negative correlation between donation frequency and serum protein values for the source plasma donors. Albumin levels were within normal ranges for both groups of plasma donors. No significant differences existed among the donor groups in total white cell counts, the percentage or absolute number of lymphocytes, T (CD3) cells, or helper T (CD4) cells. However, there were increased percentages of B (CD19) cells and decreased percentages of suppressor T (CD8+/CD11b+) cells and natural killer cells in both groups of plasma donors as compared to nondonor controls. CONCLUSION: Many plasma donors have low levels of serum protein, globulin, and IgG. In addition, they have increased percentages of B cells and decreased percentages of suppressor T and natural killer cells. The clinical significance of these findings warrants further investigation.  相似文献   
457.
Objective:  Leukocytes arriving to choriodecidua during labor are capable to secrete cytokines and collagenases that may play a role in extracellular matrix degradation leading to the rupture of amniochorion. The aim of this work was to study the role of amniochorion in the active recruitment of leukocytes through production of specific chemokines during labor.
Methods:  Amniochorion explants were obtained from women at term with spontaneous labor ( n  = 4) and subjected to cesarean section without labor ( n  = 4). Explant cultures were carried out during 24 hr and a homogenate including the culture media was made after this period. Cell free extracts were tested in Boyden chambers for chemotaxis using leukocytes from maternal blood obtained from women with ( n  = 2) and without labor ( n  = 2). Attracted cells were analyzed by flow cytometry for count and immunophenotype. Chemokines were identified in the extracts using a commercial chemiarray.
Results:  All tested amniochorion extracts induced chemotaxis for leukocytes; however, those from labor tissues induced a higher chemotactic activity than the correspondent non-in-labor tissues ( P  = 0.003). Chemotactic effect was higher over leukocytes from labor women ( P  = 0.001). More than 80% of the attracted cells were polymorphonuclear cells in all cases. IL-8 was the main chemokine found in all extracts; however its concentration was increased in extracts from labor.
Conclusions:  Fetal membranes induced chemotaxis for leukocytes and this condition is enhanced by the presence of labor. Amniochorion under active labor secretes IL-8 which induces a preferential chemotaxis for polymorphonuclears. Infiltration of these cells in choriodecidua during labor may play a role in the amniochorion degradation associated to rupture.  相似文献   
458.
Limited information is available about the sonomorphological changes in metastatic neck nodes during radiotherapy. The aim of this study was to evaluate the pattern of sonomorphological changes in metastatic neck nodes with radiotherapy. The study population consisted of 16 consecutive patients planned for radical radiotherapy to the head and neck. All patients were subjected to four ultrasound examinations: before therapy, at 46 Gy, at the conclusion of radiation and at first follow up. A total of 59 ultrasound examinations were performed on 16 patients. The difference between the mean number of nodes detected per patient before (10.6) and after (7.8) radiation was significant (P = 0.05). Sixteen nodes were categorized as malignant at first sonography, half of which reverted back to normal by the end of radiation. Changes in the sonomorphology of malignant cervical lymph nodes occur with radiotherapy with more that half demonstrating reversion to normal pattern. Future studies correlating this with histopathology should be considered.  相似文献   
459.
460.
Abstrakt 1. Bei der im Verfahren des einstweiligen Rechtsschutzes gebotenen summarischen überprüfung kann ein Anordnungsanspruch schon dann zu bejahen sein, wenn jedenfalls mehr dafür als dagegen spricht, dass die Voraussetzungen für einen Off-Label-Use nach der Rechtsprechung des BSG vorliegen. 2. Defizite des Arzneimittelrechts sollen nicht dazu führen, dass dem Versicherten der gesetzlichen Krankenversicherung unverzichtbare und erwiesenerma?en wirksame Therapien vorenthalten bleiben, obwohl die betreffenden Medikamente au?erhalb der Krankenversicherung in der nicht zugelassenen Indikation verordnet werden und verordnet werden dürfen. (Leits?tze des Bearbeiters)  相似文献   
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