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81.
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Improvement in survival to endotoxin has been seen after pretreatment with cyclooxygenase inhibitors. Because eicosapentaenoic acid (EPA), found in menhaden oil, competitively inhibits cyclooxygenase, we fed two groups of guinea pigs diets, in which the fat source was either menhaden or safflower oil, for 6 wk. A third group was allowed the safflower oil diet ad libitum. Menhaden oil-fed animals showed enhanced survival compared with safflower oil control animals 20 h after endotoxin (87 vs 63%, p less than 0.05). Ad libitum-fed safflower oil animals survived least well, with 47% alive at 20 h (p less than 0.005 vs menhaden oil group). We conclude that feeding animals a diet whose predominant lipid source is fish oil significantly improves survival after endotoxin. Dietary fat should be viewed not only as a caloric source but as a pharmacologically active substance that can have profound effects on the host's response to toxic insults.  相似文献   
84.
Group psychotherapy for adolescents is a specific clinical modality in which the adolescent is helped to define his/her identity — the major task of adolescent development. Through the work of the group the adolescent becomes aware of new behavioral possibilities in relationships with peers and authority figures. This paper examines indications and contraindications for adolescent group therapy: issues of composition, selection and types of groups; group therapy as a prime modality or as adjunct to individual or family treatment. Issues of confidentiality, group rules and group structure are reviewed. Group leadership and transference and countertransference issues are explored. A case example illustrates how group participation can assist in the separation — individuation process.An earlier version of this paper was presented at the Xth International Congress of Group Psychotherapy, Amsterdam, The Netherlands, August 27–September 2, 1989.  相似文献   
85.
Animal and human data would suggest that ultrasound causes deleterious effects to oocytes during meiosis. We directly compared the fertilization rate and embryonic development following in vitro fertilization and embryo transfer of those oocytes exposed to ultrasound and those not exposed in the same patient. In 39 unscreened patients a combination of laparoscopy and ultrasound was used for oocyte recovery. Laparoscopy was performed first on the most accessible ovary (usually the right) and at least one oocyte was obtained. Ultrasoundguided oocyte recovery was successful in the other inaccessible ovary. To assess how oocytes obtained by ultrasound or laparoscopy related to the pregnancy rate, two groups of patients were evaluated in whom the embryos transferred either had been exposed to ultrasound or had not been. The fertilization and the embryo cleavage rates were not significantly different between the ultrasoundexposed and the unexposed groups. The pregnancy rate was also not significantly different [9 of 49 (18.4%) for ultrasound exposed versus 14 of 74 (18.9%) for unexposed]. There was one early spontaneous abortion in each group. Further analysis of a group of 40 patients, in whom the oocytes were exposed to ultrasound in situ, after the endogenous luteinizing hormone (LH) surge had begun 1–27 hr earlier, revealed that 6 became pregnant (15%). This preliminary study suggests that exposure of human oocytes to ultrasonic waves, either during the different phases of meiosis or after the completion of meiosis, did not significantly influence the developmental potential of the in vitro fertilized embryos.  相似文献   
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Murine spleen cells from normal donors were cultured in vitro with trinitrobenzene sulfonate (TNBS)-conjugated soluble proteins, i.e., bovine gamma globulin (TNP-BGG) or bovine serum albumin (TNP-BSA). Addition of 100 μg of any of these TNP-proteins to the spleen cell cultures led to the generation of cytotoxic T-cell effectors which were H-2-restricted and TNP- specific. The lytic potential of such effectors was comparable to that generated by sensitization with TNBS-modified syngeneic cells, and was restricted to haplotypes shared at the K or K plus I-A, or the D regions of the H-2 complex. Greater effecter cell activity was generated by addition of TNP-BGG against TNBS-modified targets which shared K plus I-A than against modified targets which shared the D region with the responding cells, which suggests that the same immune response genes are involved when the response is generated by the addition of TNP-conjugated soluble proteins or of TNBS- modified cells. H-2-restricted, TNP-specific effecter cells were generated by culturing mouse spleen cells with syngeneic cells which had been preincubated with TNP- BGG or TNP-BSA for 1.5 h. The addition of unconjugated soluble proteins to the cultures did not result in cytotoxic effectors detectable on H-2-matched targets, whether the targets were prepared by modification with TNBS, or by incubation with either the unconjugated or TNP-conjugated proteins. Depletion of phagocytic cells in the tumor preparation by Sephadex G-10 column fractionation before incubation with TNP-BSA had no effect on their lysis by the relevant effector cells. Immunofluorescent staining of tumor target cells with anti-TNP antibodies indicated that TNP could be detected on the tumor cells within 10 rain of incubation with TNP-BSA. The cytotoxic response generated by addition of the TNP-proteins to spleen cell cultures was found to be T-cell dependent at the effector phase, as shown by the sensitivity of the lytic phase to absorbed RAMB and complement. Furthermore, the response did not appear to be attributable to antibody-dependent cellular cytotoxicity. Three mechanisms were considered which could account for the generation of H-2-restricted, TNP-specific, cytotoxic T-cell effectors by the addition of soluble TNP-proteins. These include covalent linkage of activated TNP groups from the soluble proteins to cell surface components, macrophage processing of the soluble conjugates and presentation to the responding lymphocytes in association with H-2-coded self structures, or hydrophobic interaction of the TNP-proteins to cell surfaces. Results obtained from sodium dodecyl sulfate gel patterns indicating that cell-bound TNP was still linked to BSA, and the observation that phagocytic-depleted cells could interact with the soluble TNP-proteins and function as H-2-restricted targets, appear not to favor the first two proposed mechanisms.  相似文献   
88.
目的:对长期以来关于骨纤维结构不良大量相关研究及文献进行回顾,综述骨纤维结构不良的诊断和治疗的最新进展。资料来源:通过计算机互联网检索OVID数据库1966-01/2006-10关于骨纤维结构不良的文献,检索词:Osteofibrous dysplasia,限定语言种类为English。同时检索1994-01/2006-10中国全文期刊数据库有关骨纤维结构不良的文献,检索词为:骨纤维结构不良,限定语言种类为中文。资料选择:选择与骨纤维结构不良相关的观察对比研究、经验总结、个案报道、最新研究进展等文献,力求资料全面,排除重复研究。资料提炼:共收集相关国内外文献41篇,排除重复性研究11篇,采用30篇,包括关于骨纤维结构不良定义、发病机制、病理、诊断及治疗等。资料综合:①骨纤维结构不良是一种起源于纤维组织的良性骨肿瘤。发病率低、误诊率高。目前具体发病机制不明,现认为与常染色体显性遗传有关。②骨纤维结构不良好发于胫骨,症状为局部肿块。特征性影像学表现为胫骨中段前侧皮质膨胀性密度减低。确诊方法为病理检查。重点与骨纤维异常增殖症、造釉细胞瘤相鉴别,现有大量研究证明该病与造釉细胞瘤有联系。③治疗上过去认为10岁以前应保守治疗,10岁后选择手术治疗,目前倾向于早期骨膜外切除手术治疗。结论:骨纤维结构不良发病率低,对该病认识较少,误诊率较高,重点需与骨纤维异常增殖症、造釉细胞瘤相鉴别,应提高对该病的认识与重视程度,对可疑者行病理检查,确诊者行骨膜外切除,切除范围较大的病例行重建手术。  相似文献   
89.
目的:观察白藜芦醇对豚鼠、小鼠和家兔离体心肌收缩力和心率的影响。方法:实验于2005-08/2006-12在河北医科大学西校区实验中心完成。①实验分组:离体豚鼠、小鼠和家兔心肌各分为9组:空白对照组、溶剂对照组、递增累积浓度白藜芦醇组(浓度为10-6,3×10-6,10-5,3×10-5,10-4,3×10-4mol/L),白藜芦醇对照组(5×10-5mol/L),ATP敏感性钾通道阻断剂格列苯脲(5×10-5mol/L)预孵育 白藜芦醇组,钙激活钾通道阻断剂四乙胺(10-3mol/L)预孵育 白藜芦醇组,电压依赖性钾通道阻断剂4-氨基吡啶(10-3mol/L)预孵育 白藜芦醇组,内向整流钾通道阻断剂氯化钡(10-4mol/L)预孵育 白藜芦醇组,乙酰胆碱调节钾通道阻断剂阿托品(10-5mol/L)预孵育 白藜芦醇组。②实验方法:不同类型的钾通道阻断剂均预孵育15min后,分别加入白藜芦醇(终浓度为5×10-5mol/L),连续记录30min,与相应动物白藜芦醇对照组相比较。③评估指标:分析不同阻断剂与白藜芦醇联用对心房收缩力下降率及心率抑制率的影响。结果:①白藜芦醇可降低豚鼠和小鼠离体心肌收缩力和心率(P<0.05),并被ATP敏感性钾通道阻断剂格列苯脲和钙激活钾通道阻断剂四乙胺部分阻断。②白藜芦醇可降低家兔离体心肌心率,格列苯脲可阻断白藜芦醇的负性变时作用。③电压依赖性钾通道阻断剂4-氨基吡啶、内向整流钾通道阻断剂氯化钡、乙酰胆碱调节钾通道阻断剂阿托品均不能阻断白藜芦醇对3种不同动物离体心房收缩力和心率的作用(P>0.05)。结论:白藜芦醇可呈剂量依赖性减慢豚鼠、小鼠和家兔的心率,白藜芦醇可减弱豚鼠心肌收缩力,其作用是与开放ATP敏感性钾通道有关,而与电压依赖性钾通道、内向整流钾通道和乙酰胆碱调节钾通道无关。同时,钙激活钾通道也参与了白藜芦醇对豚鼠和小鼠离体心房收缩力和/或心率的抑制作用。白藜芦醇对离体心肌收缩力和心率的作用有种属差异性。  相似文献   
90.
The aim was to evaluate 24 hr urine catecholamine, HMMA and HVA excretion in relation to ploidy in phaeochromocytoma. Data from five diploid and nine tetraploid tumours showed a significant reduction in urine noradrenaline (p = 0.02) and HMMA (p = 0.03) in diploid tumours but no difference in adrenaline, dopamine and HVA excretion using the Mann-Whitney U test. None of the patients showed recurrence after a mean of 5.7 years of follow up. A review of published ploidy studies in phaeochromocytoma shows that malignancy is more than six times more common in non-diploid tumours but diploidy does not equate with benignity. No biochemical marker is a reliable index of malignancy. All patients should undergo lifetime review for recurrence.  相似文献   
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