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91.
92.
Efforts to prolong thoracic paravertebral block (TPVB) analgesia include local anesthetic adjuvants, such as dexamethasone (Dex). Previous studies showed that both perineural (PN) and intravenous (i.v.) routes could prolong analgesia. As PN Dex is an off‐label use, anesthesiologists should be fully informed of the clinical differences, if any, on block duration. This study was designed to evaluate the two administration routes of Dex for duration of analgesia in TPVB. Ninety‐five patients scheduled for Ivor‐Lewis esophagectomy were randomized to receive TPVB (0.5% ropivacaine 15 ml), PN or i.v. Dex 8 mg. The primary end point was the duration of analgesia. The secondary end points included pain scores, analgesic consumption, adverse effects rate, and incidence of chronic pain at 3 months postoperatively. The PN‐Dex group showed better analgesic effects than the i.v.‐Dex group (p < 0.05). Similarly, the visual analogue scale scores in patients at 2, 4, 8, and 12 h postoperatively were lower in the PN‐Dex group than the i.v.‐Dex group (p < 0.05). The analgesic consumption in both the PN‐Dex and i.v.‐Dex groups was significantly lower than that in the control group (p < 0.05). Regarding the incidence of chronic pain, regardless of route, Dex decreased the incidence of chronic postsurgical pain and neuropathic pain at 3 months after surgery (p < 0.05), but there were no clinical differences between the i.v.‐Dex and PN‐Dex groups. Perineural dexamethasone improved the magnitude and duration of analgesia compared to that of the i.v.‐Dex group in TPVB in Ivor‐Lewis esophagectomy. However, there were no clinically significant differences between the two groups in the incidence of chronic pain.

Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? Both perineural (PN) and intravenous (i.v.) dexamethasone (Dex) could prolong the duration of a nerve block, but the superiority of either route is still inconclusive. WHAT QUESTION DID THIS STUDY ADDRESS? The study investigated the effects of the two routes of Dex added to ropivacaine on analgesic effects of thoracic paravertebral block in patients undergoing Ivor‐Lewis esophagectomy. WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? These results extend the knowledge of the superior analgesic effect of Dex for the management of perioperative pain in the setting of Ivor‐Lewis Esophagectomy. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? Because PN Dex is an off‐label use, our study conformed the safety of Dex as PN adjuvants and extended its application field in clinical work.  相似文献   
93.
对脑卒中偏瘫本质的认识及其在针灸治疗中的指导作用   总被引:9,自引:0,他引:9  
林滨  丁德谦  杨芳 《中国针灸》2002,22(12):15-23
脑卒中偏瘫是中枢性瘫痪的一种,它的本质是运动模式质的改变,因此它的康复过程也就是运动模式质变的过程。本文将偏瘫康复过程分为3期,探讨了各期针灸治疗的目的及原则,并指出传统的肌力练习并不适合于痉挛期,而应以抑制痉挛、促进正常运动模式的发展、促进分离运动的形成为主要原则。  相似文献   
94.
本文利用能表达HuTNFβ的工程菌株(P20KLT)按常规培养及扩增.即采用LB培养液(内含Amp100.μg/ml Tet 5μg/ml);1:40扩增.当A550达0.1时,加入IAA(20μg/ml),当A550为1.0时,中止培养,离心(5000rpm,4℃)收集菌体。在菌体中按1:5加入缓冲液,冰浴中超声破碎,13,000rpm高速离心20分钟,  相似文献   
95.
Bone cancer pain (BCP) is the most common complication in patients with bone cancer. Glial cell line‐derived neurotrophic factor (GDNF) is believed to be involved in chronic pain conditions. In this article, the expression and roles of GDNF were studied in a rat model of BCP induced by tibia injection of Walker 256 rat mammary gland carcinoma cells. Significant mechanical and thermal hyperalgesia and ongoing pain were observed beginning as early as day 5 post injection. The expression level of GDNF protein examined on day 16 after tibia injection was decreased in the L3 dorsal root ganglion (DRG) and lumbar spinal cord, but not in other spinal levels or the anterior cingulate cortex. Phosphorylation of Ret, the receptor for GDNF family ligands, was also decreased. Furthermore, normalizing GDNF expression with lentiviral vector constructs in the spinal cord significantly reduced mechanical and thermal hyperalgesia, spinal glial activation, and pERK induction induced by tibia injection, but did not affect ongoing pain. Together these findings provide new evidence for the use of GDNF as a therapeutic treatment for bone cancer pain states.  相似文献   
96.
97.

Background

Seneca Valley virus (SVV-001) is a nonpathogenic oncolytic virus that can be systemically administered and can pass through the blood–brain barrier. We examined its therapeutic efficacy and the mechanism of tumor cell infection in pediatric malignant gliomas.

Methods

In vitro antitumor activities were examined in primary cultures, preformed neurospheres, and self-renewing glioma cells derived from 6 patient tumor orthotopic xenograft mouse models (1 anaplastic astrocytoma and 5 GBM). In vivo therapeutic efficacy was examined by systemic treatment of preformed xenografts in 3 permissive and 2 resistant models. The functional role of sialic acid in mediating SVV-001 infection was investigated using neuraminidase and lectins that cleave or competitively bind to linkage-specific sialic acids.

Results

SVV-001 at a multiplicity of infection of 0.5 to 25 replicated in and effectively killed primary cultures, preformed neurospheres, and self-renewing stemlike single glioma cells derived from 4 of the 6 glioma models in vitro. A single i.v. injection of SVV-001 (5 × 1012 viral particles/kg) led to the infection of orthotopic xenografts without harming normal mouse brain cells, resulting in significantly prolonged survival in all 3 permissive and 1 resistant mouse models (P < .05). Treatment with neuraminidase and competitive binding using lectins specific for α2,3-linked and/or α2,6-linked sialic acid significantly suppressed SVV-001 infectivity (P < .01).

Conclusion

SVV-001 possesses strong antitumor activity against pediatric malignant gliomas and utilizes α2,3-linked and α2,6-linked sialic acids as mediators of tumor cell infection. Our findings support the consideration of SVV-001 for clinical trials in children with malignant glioma.  相似文献   
98.
Cancer stem cells (CSCs) are a relatively rare subpopulation of tumor cell with self-renewal and tumorigenesis capabilities. CSCs are associated with cancer recurrence, progression, and chemoradiotherapy resistance. Establishing a reliable platform for CSC enrichment and study is a prerequisite for understanding the characteristics of CSCs and discovering CSC-related therapeutic strategies. Certain strategies for CSC enrichment have been used in laboratory, particularly fluorescence-activated cell sorting (FACS) and mammosphere culture. However, these methods fail to recapitulate the in vivo chemical and physical conditions in tumors, thus potentially decreasing the malignancy of CSCs in culture and yielding unreliable research results. Accumulating research suggests the promise of a biomaterial-based three-dimensional (3D) strategy for CSC enrichment and study. This strategy has an advantage over conventional methods in simulating the tumor microenvironment, thus providing a more effective and predictive model for CSC laboratory research. In this review, we first briefly discuss the conventional methods for CSC enrichment and study. We then summarize the latest advances and challenges in biomaterial-based 3D CSC platforms. Design strategies for materials, morphology, and chemical and physical cues are highlighted to provide direction for the future construction of platforms for CSC enrichment and study.  相似文献   
99.
Five new guaiane-type sesquiterpenoids, hedyosumins A-E (1-5), together with five known ones (6-10), were isolated from the aerial parts of Hedyosmum orientale. Two known sesquiterpenoids, 10alpha-hydroxy-1,5alpha H-guaia-3,7(11)-dien-8alpha,12-olide and 9alpha-hydroxyasterolide, were obtained as natural products for the first time. Their structures were elucidated on the basis of spectroscopic methods. 9alpha-Hydroxyasterolide (7) showed moderate activities against A-549 and HL-60 tumor cell lines with the IC 50 values of 3.1 and 8.8 microM, respectively.  相似文献   
100.
Penicillium herquei isolate GA4 was isolated from the infected Conchocelis of Porphyra yezoensis. A large-scale fermentation using yeast extract sucrose medium and repeated chromatography afforded a new symmetrical urea derivative, hualyzin (1). The structure was determined by detailed NMR spectroscopic investigations and MS fragmentation analysis.  相似文献   
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