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131.
132.
In 44 patients with one or more calculi in the upper two-thirds of the ureter, single-stage percutaneous nephrolithotomy was performed through a middle or upper calyceal nephrostomy after cystoscopic placement of an occlusion balloon catheter distal to the calculus; in 42, the procedure was successful. The occlusion balloon catheter permitted retrograde opacification of all systems for enhanced renal puncture. In the last 30 patients an attempt was made either to push the calculus upward mechanically or to flush it upward into the renal pelvis with carbon dioxide or dilute contrast material. This was successful in 24 of these patients. Prior overnight occlusion of the ureter by means of ureteral dilatation further facilitates dislodgment of the calculus, which was successful in 12 of 13 patients. 相似文献
133.
134.
Visual identification of bacterially contaminated red cells 总被引:1,自引:0,他引:1
There have been increasing numbers of reports of transfusion-acquired Yersinia enterocolitica bacteremia (including several fatal cases). Fifteen units of whole blood were inoculated with various concentrations of Y. enterocolitica serotype 0:3 and processed into AS-3 preserved red cells (RBCs). Consistent growth of the organism was found at inoculum concentrations greater than or equal to 10 colony-forming units per mL. In all 13 units of RBCs that supported the growth of Y. enterocolitica, a darkening in color (due to hemolysis and a decrease in pO2) was observed in the bag. The attached sample segments, which were sealed from the main unit, remained sterile and did not darken. This color change was apparent in all the contaminated units by Day 35, which was 1.5 to 2 weeks after the bacteria were first detected in cultures of the blood. Hence, by comparison of the color of the segment tubing with that of the unit itself, units grossly contaminated with Y. enterocolitica can be identified prior to transfusion. Moreover, review of photographs on file at the Centers for Disease Control revealed this dramatic color change in 2 units of blood that caused transfusion-transmitted sepsis (Enterobacter agglomerans and an unidentified gram-negative bacillus, not Yersinia sp.), which demonstrated that the color change was not limited to Y. enterocolitica. This method of visual identification of contaminated units of blood could decrease the incidence of posttransfusion bacterial sepsis. 相似文献
135.
136.
The genes encoding effector molecules of mature T cells, IL-2, perforin and
IL-4, were found to be expressed in vivo in the most primitive subsets of
thymocytes of adult mice. These subsets have previously been identified by
their cell surface markers and by their expression of other T
lineage-associated genes. While IL-2, perforin and IL-4 are expressed in
distinct patterns, all three are expressed before the induction of RAG-1
and pre-TCR alpha mRNA expression, and are confined to subsets of cells
that apparently have not yet undergone commitment to the T lineage. Thus,
expression of T cell response genes appears to be one of the earliest
markers of lymphocyte differentiation. Activation events marked by CD69
induction occur in these early cell types, but the response gene expression
by these cells is separable from CD69 expression. IL-2 and perforin are
induced again much later in thymocyte development, during TCR-dependent
repertoire selection. At those stages, IL-2 protein and RNA levels per cell
are higher, but the fraction of cells expressing IL-2 appears to be much
lower than in the most immature stages. In addition, a striking feature of
the immature populations is the robust IL-2 expression by presumptive
immature NK cells. These findings are discussed in terms of the
developmental origins of lineage specificity in T cell response gene
regulation.
相似文献
137.
Kaposi's sarcoma (KS) and non-Hodgkin's lymphomas (NHL) are common consequences of HIV infection. These tumours appear to be precipitated by herpesviruses. Epstein-Barr virus (EBV) is implicated as a cause of up to 50% of systemic NHLs and up to 100% of central nervous system lymphomas in patients with AIDS. KS may be a consequence of the newly identified gamma-herpesvirus KSHV (KS-associated herpesvirus or HHV-8). This herpesvirus is found in all KS biopsies from different epidemiologic forms of this disease. KSHV is also implicated in the pathogenesis of a rare form of B cell lymphoma called body-cavity based lymphoma or primary effusion lymphoma (PEL). 相似文献
138.
139.
Zusammenfassung Der Beitrag befasst sich mit Rechtsverhältnissen am menschlichen Körper unter Berücksichtigung einer möglichen Kommerzialisierung. Medizin und Wissenschaft sind auf Organe und Gewebe zur adäquaten Versorgung der Bevölkerung, aber auch zur Zukunftssicherung des Forschungsstandortes Deutschland angewiesen. Rückläufige Spenderzahlen haben zu einer Organ- und Gewebeknappheit in Deutschland geführt und die Diskussion um eine Kommerzialisierung von Organ- und Gewebetransplantationen wieder entbrennen lassen. Den geäußerten Kommerzialisierungstendenzen stehen strafsanktionierte Regelungen im Transplantationsgesetz (TPG) und Resolutionen der WHO bzw. die Bioethik-Konvention des Europarates entgegen, die Handel mit menschlichen Organen und Geweben ablehnen bzw. verbieten. Nach der Rechtsprechung des Bundesverfassungsgerichts kam dem Gesetzgeber im Anwendungsbereich des TPG unter Berücksichtigung der medizinischen Möglichkeiten, der ethischen Anforderungen und der gesellschaftlichen Vorstellungen ein weiter Beurteilungs- und Gestaltungsspielraum zu. Trotz der Regelungen im TPG verschärft sich der Organ- und Gewebemangel in Deutschland. Deshalb erfährt die gesetzgeberische Gestaltung vermehrt Kritik, die sich u. a. auf die strafrechtliche Ausgestaltung des TPG und die ausgebliebene Förderung der Spendebereitschaft durch die erweiterte Zustimmungslösung bezieht. 相似文献
140.