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1.

Background  

Pneumococcal diseases remain a major cause of morbidity and mortality worldwide. Updated data on drug-resistance from different populations may be important to recognize changes in disease patterns. This study assessed current levels of penicilin resistance among Streptococcus Pneumoniae causing pneumonia in Spanish middle age and older adults.  相似文献   
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The data presented extend to a larger series of 27 consecutive renal allograft recipients treated prophylactically with OKT3 our previous observation that the acute OKT3-induced clinical syndrome is related to massive release in the circulation of some cytokines, among which are tumor necrosis factor and interferon gamma. In addition, a pilot randomized study was set up including 12 consecutive patients receiving high-dose corticosteroid treatment (0.5 g solumedrol) either before or at the same time as the first OKT3 injection. Results confirm that when corticosteroids are given in sufficient amount and, importantly, 1 hr before the first OKT3 injection, they significantly decrease the release of both tumor necrosis factor and interferon gamma. In addition, the pretreatment with corticosteroids may totally abolish the IL-2 release induced by OKT3. Given the key role the massive although transient cytokine release plays in determining the OKT3-induced acute syndrome, these results provide the biological basis supporting a precise kinetics of administration of high-dose corticosteroids to better decrease the severity of the clinical reaction.  相似文献   
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OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated.  相似文献   
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Background. Colour Doppler sonography (CDS) has become the procedure of choice in evaluating testicular perfusion but false negative findings have been reported. Objective. To determine if direct visualisation of the twisted spermatic cord using high resolution US is a reliable sign to assess testicular torsion. Material and methods. Thirty patients (aged 2–26 years) with equivocal diagnosis of testicular torsion prospectively underwent high resolution and CDS. The results were correlated with surgical findings. Serial transverse and longitudinal scans were performed to compare the scrotal contents on each side and study the complete spermatic cord course, from inguinal canal to testis, to detect a spiral twist. Results. In 14 of the 23 cases of torsion, the diagnosis was based on the colour Doppler findings in the scrotum because blood flow was absent in the symptomatic testis and detectable without difficulty on the normal side. In nine cases, CDS was unreliable; in six cases intratesticular perfusion was present in a twisted testis and in three small boys, no colour signal was obtained in either testis. In all cases of torsion, the spiral twist of spermatic cord was detected at the external inguinal ring. The twist induced an abrupt change in spermatic cord course, size and shape below the point of torsion. It appeared in the scrotum as a round or oval, homogeneous or heterogeneous extratesticular mass with or without blood flow, that could be connected cephalad with the normal inguinal cord. In the other seven cases (three late torsions of the appendix testis, one epididymo-orchitis and three torsions with spontaneous reduction), no spiral twist was detectable. Conclusion. The detection of spermatic cord spiral twist appears a reliable US sign of torsion whatever the testicular consequences. Received: 1 December 1997 Accepted: 17 June 1998  相似文献   
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