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排序方式: 共有835条查询结果,搜索用时 15 毫秒
51.
MRI lung perfusion 2D dynamic breath-hold technique in patients with severe emphysema 总被引:2,自引:0,他引:2
Sergiacomi G Sodani G Fabiano S Manenti G Spinelli A Konda D Di Roma M Schillaci O Simonetti G 《In vivo (Athens, Greece)》2003,17(4):319-324
BACKGROUND: Our aim was to prospectively evaluate a semi-quantitative pulmonary perfusion MR technique using a breath-hold 2D dynamic sequence in patients with severe pulmonary emphysema. MATERIALS AND METHODS: Thirty patients with severe emphysema were studied with pulmonary perfusion MRI. Results were compared with those obtained through lung scintigraphy, considered as the gold standard technique. We used Fast Field Echo (FFE) pulse sequences in the coronal and sagittal planes, with paramagnetic contrast agent administration. Ten healthy volunteers were studied as the control group. Three thoracic radiologists independently reviewed all the subjects, evaluating the site and entity of perfusional defects. Peak intensity and apparent mean transit time were calculated. RESULTS: MRI showed high sensitivity (86.7%) and good specifity (80.0%) in detecting perfusional defects. We observed lower peak signal intensities in emphysematous regions. CONCLUSION: Lung perfusion MR is a potential alternative to Nuclear Medicine in the evaluation of severe pulmonary emphysema. 相似文献
52.
Obuchowicz E Antkiewicz-Michaluk L Romańska I Herman ZS 《Journal of neural transmission (Vienna, Austria : 1996)》2003,110(12):1375-1391
Summary. The aim of this study was to evaluate the effect of MPTP (2 × 45mg/kg s.c., 20h apart) on striatal neuropeptide Y-like immunoreactivity (NPY-LI) in C57BL/6 mice. NPY-LI markedly increased 2 weeks after MPTP but it remained unchanged after 24h, 1 or 6 weeks. The increase in NPY-LI was accompanied by depletion of dopamine (–80%), DOPAC (–70%), 3-MT (–44%) and HVA (–52%). L-Deprenyl completely prevented the MPTP-induced NPY-LI increase, neurodegeneration of the striatal dopamine system and motor dysfunction. Clonidine attenuated the neurotoxin effect on NPY-LI and dopaminergic neurons. L-dopa/carbidopa protected NPY neurons against MPTP but slightly enhanced MPTP-induced decrease in the levels of dopamine and its metabolites. The relationship between changes in NPY-LI and dopamine and serotonin metabolism determined by HPLC was discussed. The results further extend the range of MPTP-elicited modifications in striatum and demonstrate that drugs with antiparkinsonian activity can protect NPY neurons against MPTP toxicity. 相似文献
53.
López de Romaña D Lönnerdal B Brown KH 《The American journal of clinical nutrition》2003,78(2):279-283
BACKGROUND: Several chemical forms of zinc have been proposed for food fortification, but information is needed on their absorption from common cereals having varied phytate content. OBJECTIVE: The goal was to measure zinc absorption from wheat products fortified with iron sulfate and either zinc sulfate or zinc oxide. DESIGN: Adult volunteers received either low-phytate bread (n = 11) or higher-phytate porridge (n = 11) once weekly on 2 or 3 occasions. The foods were fortified with 1 of the 2 zinc salts (60 mg elemental Zn/kg wheat flour) during week 1 and with the other during week 2, in random order. (65)Zn in the same chemical form as the fortificant was incorporated in each food to assess zinc absorption with the use of whole-body counting. The porridge group received an additional test meal fortified with zinc oxide during week 3, but the (65)Zn tracer was given as an oral solution of (65)ZnCl(2). RESULTS: Zinc absorption from bread (13.8%; 95% CI: 11.8%, 16.2%) was significantly (P < 0.001) greater than from porridge (6.4%; 5.5%, 7.6%), presumably because of the greater phytate content of the porridge. With control for food type, there were no significant differences in zinc absorption from meals fortified with zinc sulfate or zinc oxide (P = 0.24). When the porridge was fortified with zinc oxide and labeled with (65)ZnCl(2), absorption of the tracer (8.9%; 7.1%, 11.0%) was significantly (P = 0.007) greater than when (65)ZnO was incorporated in the porridge (5.6%; 4.5%, 6.9%). CONCLUSIONS: Either zinc oxide or zinc sulfate can be used to fortify wheat products consumed by presumably healthy persons. Isotopic tracers used to assess the absorption of mineral fortificants should have the same chemical form as the fortificant. 相似文献
54.
William C. MacLean Gordon L. Klein Guillermo Lopez de Romaña Enrique Massa George G. Graham 《The Journal of pediatrics》1978,92(4):562-565
Fecal fat excretion was studied after a mild episode of diarrhea in eight infants for whom adequate control data were available. Mean age of onset of diarrhea was 28 days. Duration of the episode, defined as the number of days until the infant was again feeding and libitum, averaged 5.1 days. Balance studies were carried out 3 to 13 days later. Mean fecal fat excretion rose from a prediarrhea value of 2.9 +/- 1.4 gm/day to 8.7 +/- 3.1 gm/day following diarrhea (P less than 0.001). Restudy of five infants one month later showed persistent steatorrhea in one. Mild transient steatorrhea may follow mild diarrhea in infancy and should be considered in infants who are slow to gain weight subsequent to an episode of diarrhea. 相似文献
55.
M Di Braccio G Roma A Balbi E Sottofattori M Carazzone 《Il Farmaco; edizione pratica》1989,44(9):865-881
By treating at 100 degrees C 2-aminonicotinic acid with ethyl N,N-dialkylmalonamate (I) and phosphorus oxychloride N,N-dialkyl-4-chloro-1,2-dihydro-2-oxo-1,8-naphthyridine- 3-carboxamides (II) were obtained. The reaction of compounds (II) with an excess of refluxing phosphorus oxychloride afforded N,N-dialkyl-2,4-dichloro-1,8-naphthyridine-3-carboxamides (III), which in turn were treated at room temperature with excess primary amines to give a mixture of isomeric N,N-dialkyl-2-(alkylamino or cycloalkylamino)-4-chloro-1,8-naphthyridine-3-carboxamides (IV) and N,N-dialkyl-4-(alkylamino or cycloalkylamino)-2-chloro-1,8-naphthyridine-3-carboxamides (V). When this last reaction was performed at 160 degrees C, only N,N-dialkyl-2,4-bis(alkylamino or cycloalkylamino)-1,8-naphthyridine-3-carboxamides (VI) were obtained; under the same conditions (IV c) or (V c) reacted with methylamine to give isomeric 2,4-bis(alkylamino)derivatives (VII) or (VIII), respectively. Compounds (II b), (III b), (IV a,c,d), (V a,c,d) were submitted to a wide preliminary pharmacological screening. Some of them, depending on the structure, showed antihypertensive [(IV c)], anti-inflammatory [(IV c) greater than (III b)], or, in the behavioral test, anti-aggressive [(IV d) greater than (III b)] activity. Furthermore compound (III b) caused moderate inhibition of the 5-HT induced contraction of the guinea-pig ileum. 相似文献
56.
57.
Anti-allergic therapies: effects on eosinophil progenitors 总被引:3,自引:0,他引:3
Baatjes AJ Sehmi R Saito H Cyr MM Dorman SC Inman MD O'Byrne PM Denburg JA 《Pharmacology & therapeutics》2002,95(1):63-72
Marked eosinophilic infiltration is the typical inflammatory response associated with allergic inflammation. Previous research involving animal and human models has established a role for the eosinophil/basophil hematopoietic progenitor in a systemic process of allergic inflammation. In this article, we will review the evidence implicating eosinophil/basophil progenitors in this systemic response and will discuss the rationale for targeting this cell in the treatment of allergic disease. In this context, we discuss corticosteroid treatment of allergic diseases, such as asthma and its effects on hematopoietic mechanisms, the effects of therapies that inhibit the actions of cysteinyl leukotrienes, the effects of in vivo blockade of the eosinophil-active cytokine interleukin-5, and the effects of antihistamines on hematopoiesis. It is suggested that several anti-allergic therapies exert their beneficial effects on allergic inflammation by influencing eosinophil production systemically. Therefore, targeting the systemic hematopoietic response may provide additional, more beneficial, therapeutic effects. 相似文献
58.
59.
Impact of laser coagulation in severe twin-twin transfusion syndrome on fetal Doppler indices and venous blood flow volume. 总被引:1,自引:0,他引:1
E Gratacós D Van Schoubroeck E Carreras R Devlieger E Roma L Cabero J Deprest 《Ultrasound in obstetrics & gynecology》2002,20(2):125-130
OBJECTIVE: To evaluate the impact of fetoscopic laser coagulation of placental anastomoses in severe twin-twin transfusion syndrome on fetal Doppler indices and umbilical vein blood flow volume as calculated with Doppler and two-dimensional ultrasound. METHODS: Thirty-two cases of second-trimester severe twin-twin transfusion undergoing laser therapy were examined with serial ultrasound before and 1, 3 and 5 days after therapy. Pulsatility indices in the umbilical artery and ductus venosus were measured. Blood volume flow at the level of the intra-abdominal umbilical vein was calculated by means of Doppler and two-dimensional ultrasound. The development of hydropic signs in donors was recorded. Perinatal outcome in terms of neonatal survival was recorded for all cases. RESULTS: In recipients, ductus venosus pulsatility index decreased progressively after therapy and, by day 5, median pulsatility index was significantly lower than that before therapy (0.97 vs. 0.82, P < 0.0001). Umbilical vein blood flow volume in recipient twins showed no significant variations before and after laser. In donors, umbilical artery pulsatility index decreased significantly by the first day following therapy (2.1 vs. 1.6, P < 0.0001). Previously absent or reverse umbilical end-diastolic flow reappeared after therapy in 46% (7/15) of donors. Ductus venosus pulsatility index in donors increased significantly by day 1 after therapy (0.99 vs. 1.35, P < 0.0001) but, over days 3 and 5, it returned towards preoperative values. Umbilical vein flow volume measurements (mL/min/kg) in the donor increased by approximately 50% the day after treatment (151 vs. 232, P < 0.0001) and remained elevated. Umbilical vein flow volume before laser therapy was significantly lower in donors compared to recipients (151 vs. 260, P < 0.0001), but the difference was non-significant after treatment (240 vs. 267). One or more hydropic signs developed in eight (25%) donors during the 5 days' observation after therapy. CONCLUSIONS: Laser therapy induced important changes in fetal hemodynamic parameters, resulting in a reversion of the disturbances associated with severe twin-twin transfusion syndrome. The recipient twin showed a progressive improvement of previous signs of right cardiac overload. The donor experienced a substantial increase in umbilical vein blood volume flow accompanied by a transitory state of relative right overload, which may explain the development of transient hydropic signs in a proportion of donors. 相似文献
60.