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61.
Although chronic infections with viruses such as HIV and hepatitis C virus have been associated with regulatory T cell (Treg)-mediated suppression of virus-specific CD8(+) T-cell activity, no causal relationship between Tregs and chronic viral set points has been established. Using transgenic mice in which Tregs can be selectively ablated, we now show that transient depletion of Tregs during a chronic retroviral infection allows exhausted CD8(+) T cells to regain antiviral functions, including secretion of cytokines, production of cytotoxic molecules, and virus-specific cytolytic activity. Furthermore, short-term Treg ablation resulted in long-term reductions in chronic virus loads. These results demonstrate that Treg-mediated immunosuppression can be a significant factor in the maintenance of chronic viral infections and that Treg-targeted immunotherapy could be a valuable component in therapeutic strategies to treat chronic infectious diseases.  相似文献   
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Intestinal helminths are known to subvert the host's immune response towards a Th2 response, which in turn may lead to both eosinophilia and high immunoglobulin E titers often associated with these parasites. Mycobacterium leprae infection may lead to different clinical and pathological forms. Multibacillary forms are associated with Th2 cytokines, whereas paucibacillary forms are associated with Th1 cytokines. We report a significantly higher frequency of intestinal helminthic infections in patients with the lepromatous form, a multibacillary form of leprosy (odds ratio, 2.99; 95% confidence interval, 1.82-4.95; P = 0.006) when compared with patients with paucibacillary leprosy or to a control group without leprosy. A direct correlation was also found between mycobacterial index and the frequency of intestinal helminths. Our results suggest that the presence of intestinal helminths may facilitate the establishment of M. leprae infection or the progression to more severe forms of leprosy.  相似文献   
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Zusammenfassung Grundlagen: Die sehr seltene Littrésche Hernie hat als Bruchinhalt ein Meckelsches Divertikel. Bislang ist in der Literatur keine Inkarzeration beschrieben, noch dazu in Gesellschaft mit einem Karzinoid des Divertikels. Methodik: Anhand einer Kasuistik wird der extrem seltene Bruchzufall eines inkarzerierten, karzinoidtragenden Meckelschen Divertikels pr?sentiert. Ergebnisse: Ein 84j?hriger Mann wurde wegen eines inkarzerierten Leistenbruches operiert. Es fand sich der seltene Befund eines inkarzerierten Meckelschen Divertikels. überraschenderweise ergab die nach der Resektion durchgeführte Histopathologische Untersuchung ein Karzinoid. Nach blandem Heilungsverlauf ist der Patient 12 Monate nach dem Eingriff rezidivfrei. Schlu?folgerungen: Entsprechend der Literatur und der operationstechnischen Weiterentwicklung mit deutlicher Senkung der Komplikationen nach Resektion eines Meckelschen Divertikels mu? die bislang geübte Zurückhaltung bei Resektion von Zufallsbefunden in Frage gestellt werden.   相似文献   
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31P MRS examinations of the calf muscles of 12 healthy volunteers were performed to determine T2 of the coupled ATP signals by using the 90 degrees-TE/2-2662-TE/2-acq selective spin-echo sequence for elimination of phase and intensity distortions. The T2 relaxation times obtained are much longer than those usually assumed: gamma-ATP, 93 ms; alpha-ATP, 74 ms; beta-ATP, 75 ms.  相似文献   
68.
For characterization of histopathological changes during pancreas graft rejection, pancreaticoduodenal transplants were performed in three groups: (1) Brown Norway into diabetic Lewis rats without immunosuppression, (2) Brown Norway into diabetic Lewis rats with cyclosporin A, and (3) Lewis into Lewis rats. Diffuse inflammatory infiltration of the acini by mononuclear cells indicated the onset of rejection (stage I). Shortly after acinar infiltration, damage to small and large interlobular excretion ducts occurred. This took the form of florid circumferential inflammation and vacuolar degeneration of epithelium similar to the bile duct damage seen in primary biliary cirrhosis, graft-versus-host disease, and liver allograft rejection (stage II). Thereafter, endothelialitis and destruction of islets were evident, consistent with a more advanced and irreversible stage of rejection (stage III). Acinar inflammation and moderate duct lesions were not prevented by immunosuppression but were delayed. Nonetheless, severe vascular changes and loss of islets were avoided. We conclude that duct lesions are a reliable criterion for pancreas allograft rejection. They are more sensitive than vascular changes and more specific than cellular infiltration of acinar tissue, which may also occur in infection.  相似文献   
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A five-state compartment model of trends in illicit drug use in Australia is parameterized using data from multiple sources. The model reproduces historical prevalence and supports what-if analyses under the assumption that past trajectories of drug escalation and desistance persist. For fixed initiation, the system has a unique stable equilibrium. The chief qualitative finding is that even though some users escalate rapidly, regular injection drug use still adjusts to changes in incidence with considerable inertia and delay. This has important policy implications, e.g., concerning the timing of reductions in drug-related social cost generated by interventions that reduce the social cost per injection user versus those that cut drug initiation.  相似文献   
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This paper focuses on the concept of compassion and its meaning for nursing practice. Compassion is often considered to be an essential component of nursing care; however, it is difficult to identify what exactly comprises compassionate care. To begin with, there is a general discussion of the meaning of compassion and an examination of its common usage. An argument then is presented that compassion is more than just a natural response to suffering, rather that it is a moral choice. The paper outlines the extent to which this concept has implications for nursing care, highlighting some of the obstacles that nurses need to overcome in order to maintain this essential moral value of the caring role.  相似文献   
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