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排序方式: 共有936条查询结果,搜索用时 31 毫秒
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Aldo Cunha Medeiros Irami Araújo Filho Vítor Brasil Medeiros Laíza Araújo Mohana Pinheiro Flávio Henrique Miranda Araújo Freire Italo Medeiros Azevedo José Brand?o-Neto 《Journal of investigative surgery》2007,20(1):41-48
After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation. 相似文献
3.
Murine thymus has been demonstrated to contain both cholinergic receptors and acetylcholinesterase activity. In the present study we have investigated the presence of the enzyme choline acetyltransferase in this organ, which is responsible for the synthesis of acetylcholine. Results reported here demonstrate that (1) an appreciable amount of the enzyme is already present in the thymus on the day of birth; (2) its expression is developmentally regulated; and (3) thymic atrophy, induced in young (2-week-old) and adult (6-week-old) mice by i.p. injection of hydrocortisone for 2 days, is accompanied by significant reduction of choline acetyltransferase activity only in young mice. Altogether these results demonstrate the presence in the murine thymus of functionally relevant markers of the cholinergic system that might interface the interactions between the nervous and immune systems. 相似文献
4.
Roberto Valcavi Michele Zini Simona Davoli Italo Portionli 《Clinical endocrinology》1992,37(4):360-364
OBJECTIVE: We have investigated the late GH rise occurring 3-5 hours after oral glucose administration. We have assessed the effect of endogenous cholinergic enhancement with pyridostigmine on the delayed GH rise following oral glucose loading in normal subjects. DESIGN: Placebo or 75 g oral glucose was given to the normal subjects 3 hours before 120 mg oral pyridostigmine or placebo. Four tests were carried out at random. (0 min) + placebo (180 min); test 2: glucose (0 min) + placebo (180 min); test 3: placebo (0 min) + pyridostigmine (180 min); test 4: glucose (0 min) + pyridostigmine (180 min). SUBJECTS: We studied eight normal subjects (four male and four female), ages 19-29 years, body mass indices 18-22 kg/m2. MEASUREMENTS: Plasma glucose and serum GH concentrations were measured for 6 hours after oral glucose or placebo administration. RESULTS: Pyridostigmine treatment significantly enhanced the GH releasing effect of prior (3 h) oral glucose. Late GH peak obtained by oral glucose loading rose from (mean +/- SEM) 17.4 +/- 4.6 to 37.2 +/- 9.0 mU/l (P < 0.05) after pyridostigmine, while GH peak following placebo plus pyridostigmine was 12.4 +/- 2.0 mU/l (P < 0.05 vs glucose plus pyridostigmine). The analysis of GH area under curves (AUCs) in the second phase of the tests (180-360 min) confirmed that glucose plus pyridostigmine released a greater amount of GH (4128 +/- 764 mU/l/3h) than glucose (1694 +/- 494 mU/l/3h, P < 0.001) or pyridostigmine alone (1292 +/- 150 mU/I/3h, P < 0.001). CONCLUSIONS: Pyridostigmine, an indirect cholinergic drug likely to inhibit somatostatin secretion from the hypothalamus, enhanced the late GH releasing activity of oral glucose. There is evidence that glucose suppresses plasma GH initially by increasing hypothalamic somatostatin release. This would result in an increase in the pituitary stores of GH. We propose that the delayed GH rise after oral glucose occurs when there is a fall in hypothalamic somatostatinergic tone; this is further reduced by the administration of pyridostigmine. At this time the pituitary stores of GH are released as a consequence of resumption of hypothalamic GHRH activity. This leads to the late GH rise. 相似文献
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Substance abuse and psychopathology 总被引:1,自引:0,他引:1
Massimo Clerici Italo Carta Carlo Lorenzo Cazzullo 《Social psychiatry and psychiatric epidemiology》1989,24(4):219-226
This report evaluates, using DSM III, the psychopathological profile of 226 heroin users taken in at the clinical centre of "Cascina Verde" Therapeutic Community (Milan, Italy) and admitted to a psychotherapeutic, retraining, integrated, both out-and-in-patient treatment. The outcome shows that 30% of subjects are to be diagnosed according to Axis I while 61% are to be considered among Axis II personality disorders. A portion of 16% is to be referred to the "schizophrenic spectrum", 25% has histrionic, narcissistic, antisocial and borderline personality disorders and the remaining are to be referred to an extremely heterogeneous category. The report shows also data concerning Axes IV and V, always according DSM III. 相似文献
7.
Human muscle sympathetic neural and haemodynamic responses to tilt following spaceflight 总被引:6,自引:5,他引:6
Benjamin D. Levine James A. Pawelczyk rew C. Ertl James F. Cox Julie H. Zuckerman ré Diedrich Italo Biaggioni Chester A. Ray Michael L. Smith Satoshi Iwase Mitsuru Saito Yoshiki Sugiyama Tadaaki Mano Rong Zhang Kenichi Iwasaki Lynda D. Lane Jay C. Buckey Jr William H. Cooke Friedhelm J. Baisch David Robertson Dwain L. Eckberg C. Gunnar Blomqvist 《The Journal of physiology》2002,538(1):331-340
8.
A Bacia L Aloe M Fusco G Vantini A Leon B Oderfeld-Nowak 《Acta neurobiologiae experimentalis》1992,52(1):1-7
The cellular localization of the nerve growth factor-like immunoreactivity (NGF-LIR) has been studied in the intact adult rat brain at the level of the hippocampus and the septum. Immunolabelling for NGF combined with counterstaining with cresyl violet and double immunostaining technique, which allowed simultaneous localization of NGF-LIR and that of astroglial marker -GFAP, were used. The data indicate neuronal localization of NGF-like immunoreactivity and a lack of colocalization of NGF-LIR with the immunoreactivity of GFAP in the hippocampus. These data are consistent with in situ hybridization results for NGF and immunocytochemical results for pro-NGF localization obtained by others. At the septal level, apart from neuronal localization of NGF-LIR, single NGF-like immunoreactive astrocytes have been observed. This suggests that, although to a very small extent, in vivo intact brain astrocytes may, just as astrocytes growing in vitro, synthesize NGF-like molecules. This finding may be of importance in better understanding the trophic support for NGF responsive cholinergic neurones in the brain. 相似文献
9.
Nissar A. Darmani Angelo A. Izzo Brian Degenhardt Marta Valenti Giuseppe Scaglione Raffaele Capasso Italo Sorrentini Vincenzo Di Marzo 《Neuropharmacology》2005,48(8):1154
The endogenous cannabimimetic compound, and anandamide analogue, N-palmitoyl-ethanolamine (PEA), was shown to exert potent anti-inflammatory and analgesic effects in experimental models of visceral, neuropathic and inflammatory pain by acting via several possible mechanisms. However, only scant data have been reported on the regulation of PEA levels during pathological conditions in animals or, particularly, humans. We review the current literature on PEA and report the results of three separate studies indicating that its concentrations are significantly increased during three different inflammatory and neuropathic conditions, two of which have been assessed in humans, and one in a mouse model. In patients affected with chronic low back pain, blood PEA levels were not significantly different from those of healthy volunteers, but were significantly and differentially increased (1.6-fold, P<0.01, N = 10 per group) 30 min following an osteopathic manipulative treatment. In the second study, the paw skin levels of PEA in mice with streptozotocin-induced diabetic neuropathic pain were found to be significantly higher (1.5-fold, P<0.005, N = 5) than those of control mice. In the third study, colonic PEA levels in biopsies from patients with ulcerative colitis were found to be 1.8-fold higher (P<0.05, N = 8–10) than those in healthy subjects. These heterogeneous data, together with previous findings reviewed here, substantiate the hypothesis that PEA is an endogenous mediator whose levels are increased following neuroinflammatory or neuropathic conditions in both animals and humans, possibly to exert a local anti-inflammatory and analgesic action. 相似文献
10.
Barbara Longobardi Elena De Martin Claudio Fiorino Italo Dell'oca Sara Broggi Giovanni Mauro Cattaneo Riccardo Calandrino 《Radiotherapy and oncology》2005,77(2):148-156
BACKGROUND AND PURPOSE: To investigate the feasibility and the advantages of using Intensity-Modulated Radiotherapy (IMRT) for the treatment of head-and-neck cancer. Comparing different methods to deliver IMRT in this clinical setting. MATERIALS AND METHODS: Seven patients (four radical; three post-operative), treated on a 6MV Varian Linac (equipped with an 80 leaves MLC) in accordance with a routine 3DCRT plan, were replanned. Original treatment plans were computed to irradiate a primary Planning Target Volume (PTV1, 54 Gy) and then to perform a boost on a PTV2 (radical: 70.2 Gy; post-operative: 64.8 Gy). IMRT dose plans were inversely-optimized using appropriate constraints with the Helios tool on a Varian Eclipse system. Once the optimal fluences were calculated, different modalities to deliver IMRT were considered: Sliding Window (SW) and Step and Shoot (SS) techniques using a different number of intensity levels to approximate the optimal fluences (e.g. 5, 10 and 20). Mean dose, maximum dose and a number of dose-volume parameters regarding CTV1, CTV2, PTV1, PTV2, OARs (spinal and planning spinal cord, parotids, optical structures, brain and temporal mandibular joint) were considered to compare the five modalities (3DCRT, SW, SS5, SS10, SS20); the Conformity Index (CI), the Irradiated Volume (IV) and the Treated Volume (TV) were also considered in the comparison. RESULTS: A more uniform coverage of the PTV in the IMRT dose plans with respect to the 3DCRT plan was found (for PTV2: V90% = 94.3 for 3DCRT, 97.6 for SS5, 98 for SS10 and 98.1 for SW; V107% = 20.7 for 3DCRT, 5.9 for SS5, 2 for SS10 and 1.3 for SW). Concerning OARs, they all present a significant reduction of mean and/or maximum dose and dose-volume patterns assessed from DVHs: in particular the mean dose of parotids decrease on average of about 13.5Gy passing from 3DCRT to IMRT with an average reduction of NTCP ranging from about 20% to more than 40% for radically treated patients, depending on the chosen end-point. IV and TV are also slightly smaller with IMRT. The results obtained with SS techniques employing 10 or more intensity levels are comparable with those obtained with SW; no differences between SS10 and SW may be appreciated when considering the DVHs of PTV, CTV and OARs. On the other hand, in some cases SS5 may be slightly sub-effective with respect to SS10-SW when considering PTV coverage and Dmax of the spinal cord. CONCLUSIONS: With the Varian planning and delivery system, Step-and-shoot approximations of inversely optimised fluences in head-neck IMRT compare well with SW delivery, even with only five intensity levels. With a number of intensity level of 10 or more, no differences can be appreciated in PTV coverage/OAR sparing with respect to SW. 相似文献