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31.
目的:研究肝细胞癌(hepatocellular carcinoma,HCC)经导管肝动脉化疗栓塞(transcatheter arterial chemoemboli-zation,TACE)后残癌组织细胞黏附分子CD44v6和ICAM-1(intercelluar adhesion molecule-1,ICAM-1)的表达情况。方法:经病理证实的HCC 50例,包括单纯手术切除30例(对照组),TACE术后行Ⅱ期手术切除20例(TACE组)。TACE组患者术前接受1~2次不等的TACE治疗,均按统一规范标准给予化疗药物灌注+栓塞治疗。对标本行免疫组织化学PV-9000染色,其中TACE组取病灶边缘残存肿瘤部分,检测肿瘤组织CD44v6和ICAM-1的表达,将两组结果进行对照分析。结果:对照组和TACE组CD44v6和ICAM-1均有不同程度的表达。对照组CD44v6表达阳性22例(22/30,73.33%),TACE组CD44v6表达阳性13例(13/20,65%),两者间无显著性差异(P>0.05);对照组ICAM-1表达阳性19例(19/30,63.33%),TACE组ICAM-1表达阳性12例(12/20,60%),两者间亦无显著性差异(P>0.05)。对照组和TACE组中CD44v6和ICAM-1表达间均呈正相关(P<0.05)。结论:TACE术后残癌组织CD44v6和ICAM-1仍有较高的表达,TACE并不能有效降低肝癌组织CD44v6和ICAM-1的表达;两者表达呈正相关。  相似文献   
32.
BACKGROUND: Although there is increasing evidence suggesting that the vagus nerve functions as a connector between the nervous and immune systems in animals, little is known about the role of the vagus nerve in postoperative acute phase response in humans. MATERIALS AND METHODS: The extent of fever and acute phase protein response and the production of inflammatory cytokine during the early postoperative period were compared among the patients who had undergone total gastrectomy including truncal vagotomy (n = 13), those having distal gastrectomy with division of vagal branches (n = 14), and the patients with vagal nerve preserving gastrectomy (n = 12). RESULTS: There was no significant difference in serum levels of C-reactive protein, alpha-1-antirypsin, and interleukin-6 among the three groups. Also, postoperative maximum body temperature was similar. CONCLUSIONS: Vagotomy did not influence acute phase response after gastric cancer surgery. A multipathway mechanism for acute phase response including the induction of fever is suggested.  相似文献   
33.
Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.  相似文献   
34.
Contralateral intrastriatal injection of 0.1 pmol or 1 pmol of endothelin-1 produced ipsilateral turning behaviour in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the nigrostriatal pathway. This effect could be abolished by pretreatment with either the endothelinETA/B receptor antagonist bosentan (1 nmol, intrastriatally) or the dopamine D2 receptor antagonist raclopride (0.1 mg/kg, s.c.) suggesting that endothelin is acting at endothelin receptors to evoke ipsilateral turning behaviour and that this response is mediated by dopamine. Similar ipsilateral turning behaviour was observed upon intrastriatal injection of 1 pmol of endothelin-3 or the specific ETB receptor agonist, [Ala1,3,11,15]endothelin-1 when compared to endothelin-1. Pretreatment with the specific ETB receptor antagonist BQ788 blocked the ipsilateral turning response to intrastriatal injection of endothelin-1 while pretreatment with the specific ETA receptor antagonist BQ123 did not significantly change the response to injection of endothelin-1. This indicates that endothelin-1, which has affinity for both ETA and ETB receptors, is most likely acting at the ETB receptor to elicit its effect. These results suggest that low doses of endothelin may act at ETB receptors to evoke the release of dopamine from the striatum in vivo.  相似文献   
35.
The greater potency of morphine-6-glucuronide (M6G) as well as the inactivity of morphine-3-glucuronide (M3G) with respect to the antinociceptive effects of the parent molecule, morphine (MOR), have been well established. It has been suggested that M3G is an antagonist of MOR's antinociceptive and respiratory depressive effects. The present study addressed the central nervous system (CNS) interaction of these opiate metabolites on their metabolic and hormonal effects. Whole body glucose kinetics were assessed on conscious, chronically catheterized, unrestrained rats. M3G (5 μg) or H2O (5 μl) was injected intracerebroventricularly (i.c.v.) 15 min prior to the bolus administration of H2O (5 μl), M6G (1 μg), or MOR (80 μg). i.c.v. M3G (5 μg) resulted in behavioral excitation, hyperglycemia (+50%), stimulation of glucose rate of appearance (Ra; +100%), glucose rate of disappeaance (Rd; +70%), and metabolic clearance rate (MCR; +33%) within 30 min after injection with no alterations in hormone concentrations. i.c.v. M6G and MOR produced progressive hyperglycemia with significantly high catecholamine and corticosterone levels. M3G pretreatment resulted in enhanced elevations in plasma glucose levels (+52% and +18%), plasma lactate (+138% and +108%), norepinephrine (+96% and +30%), and epinephrine (+62% and +67%) in response to both i.c.v. MOR and M6G administration. These findings suggest a non-opiate and non-hormonal mechanism for M3G-induced hyperglycemia. In contrast, the metabolic and hormonal responses to i.c.v. M6G and MOR are associated with elevations in catecholamine and corticosterone levels, which are remarkably enhanced by M3G pretreatment, most likely through accelerated catecholamine release. Our findings suggest a modulatory role for MOR glucuronidation, not only by rendering it inactive, as in the case of M3G, but by an interplay of the metabolic effects of the parent molecule and its metabolite  相似文献   
36.
 Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors. One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed: (1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla. Accepted: 21 August 1996  相似文献   
37.
We report a case of an 81-year-old woman in whom lichenoid eruptions and Sjögren-like sicca syndrome developed 45 days after cholecystectomy. During surgery, one unit (130 ml) of unirradiated packed red blood cells from a male donor was transfused. The lichenoid eruptions cleared up with exfoliation; however, sicca symptoms remained during the follow-up period of four years. Histological examinations of both skin and lip biopsy specimens were in agreement with those of graft-versus-host disease (GVHD). A Y-chromosomal body was identified in the lymphocytes in the skin lesion by staining with quinacrine dihydrochloride and in the lip lesion by a method with in situ hybridization. The findings suggest that this case demonstrated the manifestations of non-fatal transfusion-associated GVHD.  相似文献   
38.
Human prostate cancer (PC) cell lines possess epidermal growth factor (EGF) receptors and secrete EGF-related polypeptides. We used an EGF receptor-blocking antibody (anti-EGF.R) to demonstrate a functional autocrine loop, as well as the interaction between this and the effects of linoleic acid (LA), an omega-6 fatty acid, on PC cell growth. The anti-EGF.R competed effectively with [125I]EGF for receptors on DU145 PC cells, and on a high-passage DU145 variant (DU145M); when added to the culture medium, it suppressed both DU145 and DU145M cell growth in a dose-dependent manner. LA, a precursor for eicosanoid synthesis, had little effect on DU145 cell growth rate but stimulated DU145M growth in a concentration-related manner over a range of 0.25-2.0 micrograms/ml. anti-EGF.R (10(-9) M) caused suppression of LA-stimulated growth of DU145M cells in serum-free medium, which was prevented by the addition of 2 nM EGF. We conclude that an EGF.R-mediated autocrine loop is involved in PC cell growth regulation and that at least one site of action may be the synthesis of eicosanoids from their LA precursor.  相似文献   
39.
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide.  相似文献   
40.
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.  相似文献   
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