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991.

Purpose  

The aim of this study was to compare the cerebral state index (CSI) and bispectral index (BIS) during propofol–fentanyl–nitrous oxide anesthesia.  相似文献   
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We have previously revealed that treating pregnant rats with 2,3,7,8-tetracholorodibenzo-p-dioxin (TCDD) reduces the expression of gonadotropins and growth hormone (GH) in the fetal and neonatal pituitary. A change in gonadotropin expression impairs the testicular expression of steroidogenic proteins in perinatal pups, and imprint defects in sexual behavior after reaching maturity. In this study, we examined whether TCDD also affects the expression of gonadotropin and GH in mice using C57BL/6J and DBA/2J strains which express the aryl hydrocarbon receptor (Ahr) exhibiting a different affinity for TCDD. When pregnant C57BL/6J mice at gestational day (GD) 12 were given oral TCDD (0.2–20 μg/kg), all doses significantly attenuated the pituitary expression of gonadotropin mRNAs in fetuses at GD18. On the other hand, in DBA/2J mice, a much higher dose of TCDD (20 μg/kg) was needed to produce a significant attenuation. Such reduction in the C57BL/6J strain continued until at least postnatal day (PND) 4. In agreement with this, TCDD reduced the testicular expression of steroidogenic proteins in C57BL/6J neonates at PND2 and 4, although the same did not occur in the fetal testis and ovary. Furthermore, TCDD reduced the perinatal expression of GH, litter size and the body weight of newborn pups only in the C57BL/6J strain. These results suggest that 1) also in mice, maternal exposure to TCDD attenuates gonadotropin-regulated steroidogenesis and GH expression leading to the impairment of pup development and sexual immaturity; and 2) Ahr activation during the late fetal and early postnatal stages is required for these defects.  相似文献   
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The aim of this study was to determine that low-intensity pulsed ultrasound (LIPUS) at an intensity of 140 mW/cm2 promotes functional and histologic improvements in sciatic nerve crush injury in a rat model and to investigate changes over time in relevant growth factors and receptors, exploring the mechanism of LIPUS in the recovery process after injury. Toe angle in the toe-off phase, regenerative axonal length, myelinated nerve fiber density, diameter of myelinated nerve fiber, axon diameter and myelin sheath thickness were significantly higher in the LIPUS group than in the sham group. Gene and protein expression of brain-derived neurotrophic factor (BDNF) was upregulated in the LIPUS group. In conclusion, LIPUS contributed to rapid functional and histologic improvement and upregulated BDNF expression after sciatic nerve crush injury in rats.  相似文献   
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Dendritic cells (DCs) are widely distributed throughout the lymphoid and nonlymphoid tissues, and are important initiators of acquired immunity and also serve as regulators by inducing self-tolerance. However, it has not been thoroughly clarified whether DCs are involved in the termination of immune responses. In this paper, we have examined the kinetical movement of dendritic cells (DCs) in the lamina propria using the 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced ileitis model (an animal model for Crohn's disease). Increased numbers of DCs were recruited to the inflammatory sites from day 1 to day 3 at which time the inflammatory responses was clearly observed, then gradually decreased to a steady-state level on day 7 along with the cessation of responses. Three subsets of DCs, PIR-A/Bhigh, PIR-A/Bmed, and PIR-A/B? DCs in the CD11c+/B220? conventional DCs (cDCs) were noted on day 3; the number of PIR-A/Bmed cDCs increased when the inflammatory responses ceased on day 7. The expression of costimulatory molecules such as CD86 and CD54 was lower in the PIR-A/Bmed DCs compared with the other two cDC subsets or splenic DCs. Furthermore, the stimulatory activity of PIR-A/Bmed cDCs was lower than those of PIR-A/Bhigh or PIR-A/B? cDCs, and far lower than that of splenic DCs. In addition, an increase in the message level of IL-10 was clearly observed in the PIR-A/Bmed cDCs on day 7 while that of proinflammatory cytokines such as IL-6 and IL-12 was low. These data demonstrate that PIR-A/Bmed cDCs which increase at the final stage of inflammation may be involved in the termination of the TNBS-induced ileitis by the delivery of anergic signals to effector T cells due to the lower expressions of costimulatory molecules and the production of immunoregulatory cytokine.  相似文献   
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Presentation and management of intravascular large B-cell lymphoma   总被引:2,自引:0,他引:2  
Intravascular large B-cell lymphoma (IVLBCL) is a rare disease entity of non-Hodgkin lymphoma according to the current WHO classification. This rare form of B-cell lymphoma is characterised by selective growth of tumour cells in the lumina of small vessels of various organs. Strange characteristics of IVLBCL, including the absence of marked lymphoadenopathy and the usually aggressive clinical behaviour, result in the delay of timely and accurate diagnosis and fatal complications. Thus, the prognosis of IVLBCL is extremely poor. The success achieved with the anti-CD20 chimeric monoclonal antibody, rituximab, represents an important milestone in the clinical practice of B-cell lymphoma. An advantage of adding rituximab to conventional chemotherapies has been shown, in the process of increasing our understanding of the clinical and pathological manifestations for IVLBCL. This Review describes the cutting edge of research on IVLBCL, and discusses the unsolved issues from biological and clinical perspectives to provide a better understanding of this rare lymphoma.  相似文献   
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