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991.
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993.
The biologically active substance P (SP) N-terminal metabolite SP1–7 has been reported to modulate several neural processes such as learning, locomotor activity and reaction to opioid withdrawal. Although all these processes are believed to be associated with dopaminergic transmission no evidence of an interaction between SP1–7 and dopamine in the case of morphine withdrawal has so far been reported. Therefore, in this work we applied in vivo microdialysis to investigate the effect of SP1–7 injection into the ventral tegmental area on dopamine release in nucleus accumbens of male rats during naloxone precipitated morphine withdrawal. The result showed that the heptapeptide enhances dopamine release and also elevates the level of the dopamine metabolite dihydroxyphenylacetic acid in this brain area. It was suggested that the observed action of the SP fragment on the dopamine system represents the underlying mechanism for a previously observed ability of SP1–7 to counteract the aversion response to morphine withdrawal.  相似文献   
994.

Background

Guidelines published in major medical journals are very influential in determining clinical practice. It would be essential to evaluate whether conflicts of interests are disclosed in these publications. We evaluated the reporting of conflicts of interest and the factors that may affect such disclosure in a sample of 191 guidelines on therapeutic and/or preventive measures published in 6 major clinical journals (Annals of Internal Medicine, BMJ, JAMA, Lancet, New England Journal of Medicine, Pediatrics) in 1979, 1984, 1989, 1994 and 1999.

Results

Only 7 guidelines (3.7%) mentioned conflicts of interest and all were published in 1999 (17.5% (7/40) of guidelines published in 1999 alone). Reporting of conflicts of interest differed significantly by journal (p=0.026), availability of disclosure policy by the journal (p=0.043), source of funding (p < 0.001) and number of authors (p=0.004). In the entire database of 191 guidelines, a mere 18 authors disclosed a total of 24 potential conflicts of interest and most pertained to minor issues.

Conclusions

Despite some recent improvement, reporting of conflicts of interest in clinical guidelines published in influential journals is largely neglected.
  相似文献   
995.
We have generated, by ethylmethane sulfonate mutagenesis, loss-of-function mutants in the Drosophila homolog of the mammalian I-kappa B kinase (IKK) complex component IKK gamma (also called NEMO). Our data show that Drosophila IKK gamma is required for the Relish-dependent immune induction of the genes encoding antibacterial peptides and for resistance to infections by Escherichia coli. However, it is not required for the Toll-DIF-dependent antifungal host defense. The results indicate distinct control mechanisms of the Rel-like transactivators DIF and Relish in the Drosophila innate immune response and show that Drosophila Toll does not signal through a IKK gamma-dependent signaling complex. Thus, in contrast to the vertebrate inflammatory response, IKK gamma is required for the activation of only one immune signaling pathway in Drosophila.  相似文献   
996.
T细胞性淋巴瘤组织CD56的检测及其与EB病毒的关系   总被引:3,自引:1,他引:3  
目的探讨T细胞性淋巴瘤(TCL)中CD56的表达情况及CD56阳性表达同爱波斯坦-巴尔病毒(EpsteinBarVirus,EBV)感染的关系。方法对46例TCL进行CD56的免疫组织化学LSAB法检测及EBERs的原位杂交检测。结果(1)46例TCL中8例CD56阳性(17.4%),其中鼻腔、咽部和口腔阳性率最高(5/17例,29.4%)。弥漫性大细胞型淋巴瘤CD56阳性率最高(6/16例,37.5%)。(2)46例TCL中24例EBERs阳性(52.2%)。(3)8例CD56阳性病例中,4例EBERs阳性。结论CD56的表达同TCL发生部位和类型有一定关系。CD56阳性表达与EB病毒感染未发现相关性  相似文献   
997.

Background  

Previous publications indicate that acupuncture is efficient for the treatment of pelvic girdle pain, PGP, in pregnant women. However, the use of acupuncture for PGP is rare due to insufficient documentation of adverse effects of this treatment in this specific condition. The aim of the present work was to assess adverse effects of acupuncture on the pregnancy, mother, delivery and the fetus/neonate in comparison with women that received stabilising exercises as adjunct to standard treatment or standard treatment alone.  相似文献   
998.
Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz, which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal changes of blood biochemistry in fish.  相似文献   
999.
We hypothesize that remodelling of action potential and intracellular calcium (Cai) dynamics in the peri-infarct zone contributes to ventricular arrhythmogenesis in the postmyocardial infarction setting. To test this hypothesis, we performed simultaneous optical mapping of Cai and membrane potential ( V m) in the left ventricle in 15 rabbit hearts with myocardial infarction for 1 week. Ventricular premature beats frequently originated from the peri-infarct zone, and 37% showed elevation of Cai prior to V m depolarization, suggesting reverse excitation–contraction coupling as their aetiology. During electrically induced ventricular fibrillation, the highest dominant frequency was in the peri-infarct zone in 61 of 70 episodes. The site of highest dominant frequency had steeper action potential duration restitution and was more susceptible to pacing-induced Cai alternans than sites remote from infarct. Wavebreaks during ventricular fibrillation tended to occur at sites of persistently elevated Cai. Infusion of propranolol flattened action potential duration restitution, reduced wavebreaks and converted ventricular fibrillation to ventricular tachycardia. We conclude that in the subacute phase of myocardial infarction, the peri-infarct zone exhibits regions with steep action potential duration restitution slope and unstable Cai dynamics. These changes may promote ventricular extrasystoles and increase the incidence of wavebreaks during ventricular fibrillation. Whereas increased tissue heterogeneity after subacute myocardial infarction creates a highly arrhythmogenic substrate, dynamic action potential and Cai cycling remodelling also contribute to the initiation and maintenance of ventricular fibrillation in this setting.  相似文献   
1000.
结直肠癌与人类乳头状瘤病毒(Human papilloma virus,HPV)感染有一定的关系,但由于检测方法、标本选择及样本数量不同,各研究结果之间差异很大。为进一步明确结直肠癌变与HPV16感染的关系,采用多聚酶链反应(Polymerase chain reaction,PCR)对82例原发性结直肠腺癌患者手术切除的新鲜癌及癌旁正常粘膜组织进行了前瞻性对照研究,检测了组织中HPV16E7DNA的表达并进行测序鉴定。结果显示,结直肠腺癌组织HPV16E7的表达阳性率(42/82)明显高于癌旁正常粘膜组织(4/82);直肠癌组织中HPV16E7的表达(64.10%)明显高于升结肠癌(18.18%),即癌灶部位距肛门越近,感染率越高;HPV16阳性率与Dukes分期相关,Dukes分期越晚感染率越高;与癌组织分化程度无相关性。结果提示结直肠癌的发生、发展可能与HPV16感染有关。  相似文献   
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