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21.
Najat MA Farsi 《BMC oral health》2007,7(1):15
Background
This study aimed to investigate the signs of oral dryness in relation to different salivary variables and to correlate subjective complaints of oral dryness with salivary flow rate. 相似文献22.
Studies were carried out to investigate the metabolism of senecionine by human liver microsomes and the role of human cytochrome P450IIIA4 in this process. Human liver microsomes metabolized senecionine to two major products, (+/-)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP) and senecionine N-oxide. The rates of product formation (DHP and senecionine N-oxide) varied widely with the microsomal samples tested. There was a 30-fold difference in DHP formation and a 25-fold difference in N-oxidation between the poorest metabolizer and the highest metabolizer of senecionine. The conversion of senecionine to DHP and senecionine N-oxide in human liver microsomes was markedly inhibited by the mechanism-based inactivators of P450IIIA4, gestodene and triacetyloleandomycin. Anti-P450IIIA4 IgG, at a concentration of 1 mg/nmol of P450, was found to inhibit completely the formation of DHP and senecionine N-oxide in human liver microsomes (HL101) having low activity toward senecionine. At 5 mg IgG/nmol P450, anti-P450IIIA4 inhibited 90 and 84% respectively of the formation of DHP and senecionine N-oxide in liver microsomes (HL110) with the highest activity toward senecionine. The formation of DHP or senecionine N-oxide was highly correlated with the amount of P450IIIA4 measured in the microsomes using polyclonal anti-P450IIIA4 IgG. The rate of DHP production also had a strong correlation with the rate of senecionine N-oxide formation (r = 0.999) and with the rate of nifedipine oxidation (r = 0.998). Our present studies provide evidence that P450IIIA4 is the major enzyme catalyzing the bioactivation (DHP formation) and detoxication (senecionine N-oxide formation) of senecionine in human liver. 相似文献
23.
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
24.
L A D'Albuquerque J Gama-Rodrigues M F De Miranda T Genzini P Sakai A A Laudanna H W Pinotti 《International surgery》1991,76(3):137-141
Forty-six patients in the postoperative period of proximal gastric vagotomy (PGV) for duodenal ulcer (DU) were studied comparatively to verify whether the dividing of the gastroepiploic nerves (Rosati's maneuver) can reduce or not the occurrence of recurrent ulcer as it was proposed. Twenty-one patients who underwent PGV associated with Rosati's maneuver (PGV-R) were compared to 25 after standard PGV (PGV-S), according to several criteria: (1) clinical evaluation; (2) pre and postoperative basal and pentagastrin-stimulated gastric acidity; (3) postoperative basal and pentagastrin-stimulated serum pepsinogen; (4) postoperative basal and sham feeding-stimulated serum gastrin; (5) postoperative endoscopy; (6) endoscopic Congo red test. Both groups were similar (P greater than 0.05) as to age, sex, levels of preoperative gastric acidity and had a 24.4 month average follow-up (12 to 58 months). There has been no significant difference between the techniques studied as to clinical, secretory, morphological or hormonal gastric tests, although PGV-R proved more effective in reducing basal gastric acidity than PGV-S (P less than 0.05). We concluded that Rosati's maneuver does not improve the results obtained with PGV, although it provided greater reduction of basal gastric acidity than PGV-S. 相似文献
25.
Carlos Cotrim Otília Sim?es M J Loureiro Pedro Cordeiro Rita Miranda Cecília Silva Teresa Avillez Manuel Carrageta 《Revista portuguesa de cardiologia》2006,25(5):529-533
We describe the case of a pregnant woman with idiopathic pulmonary arterial hypertension, a responder in right heart catheterization, followed since the first trimester in outpatient consultations, admitted to hospital at 23 weeks gestation. She was treated with inhaled iloprost until delivery (at 34 weeks gestation) and continuous infusion of iloprost throughout the perioperative period and following days. This line of therapy has proved efficacious in previous cases. The authors present echocardiographic images that document acute changes in ventricular synchrony during inhalation of iloprost. 相似文献
26.
27.
目的通过对国人脑池显微解剖的研究,以指导显微神经外科手术和进一步理解影像学解剖的重要临床意义和应用价值。方法对15具经福尔马林固定的国人成年头颅标本的颅内各个脑池进行显微解剖研究,测量和描述各脑池的位置、大小、形态及结构。结果颅内重要的脑池有(1)嗅池:长度为(32.68±2.97)mm,宽度为(7.18±1.82)mm,深度为(7.20±1.27)mm;(2)视交叉池:侧壁长度为(14.88±3.07)mm,上表面前壁长(14.20±1.47)mm,后壁长(10.37±1.59)mm;(3)颈内动脉池:长度为(15.06±3.07)mm,宽度为(12.01±1.32)mm;(4)终板池:底边左侧长度为(8.99±1.15)mm,右侧长度为(21.00±1.09)mm,最大宽径为(16.42±2.58)mm;(5)脚间池:最大深度为(19.47±2.28)mm,池顶宽度为(11.35±2.85)mm;(6)脚池:为三角形,三边长度分别为(10.48±2.56)mm,(9.64±1.78)mm,(3.58±0.25)mm;(7)外侧裂池:上部长度为(18.63±2.02)mm,基底部长度为(38.08±3.22)mm,宽度为(5.65±0.92)mm,深度为(7.02±2.28)mm;(8)胼胝体池:平均最大宽径为(3.44±0.40)mm;(9)四叠体池:最大长径为(19.37±3.38)mm,最大宽径为(15.24±2.37)mm,最大前后径为(3.65±0.57)mm;(10)环池:为环形,最大宽度为(3.16±0.37)mm;(11)小脑延髓池:最大长度为(18.77±1.77)mm,最大宽度为(32.4 相似文献
28.
Thomas M. Gehring PhD Daniel Marti MS MD Andrea Sidler MA 《Child psychiatry and human development》1994,25(2):125-138
Perceptions of family cohesion and hierarchy structures were assessed by theFamily System Test (FAST), a clinically-derived figure placement technique. Parents (N=140) and their preadolescent offspring (N=70) completed typical and conflict representations in individual as well as group settings. Typical representations were characterized by balanced family structures (i.e. cohesive and moderately hierarchical) and those displaying conflict situations showed predominantly unbalanced patterns. FAST portrayals were related to respondent (mother vs. father vs. child). Fathers represented typical family relations as balanced more often than mothers. Regarding conflict representations, children were more likely than fathers to portray the family as unbalanced. However, analyses of representations of the same family (i.e. intra-family comparisons) indicated that all respondents differed in their perceptions and, that fathers' typical portrayals showed most often the same structure as those done by the family members as a group. 相似文献
29.
随着磁共振功能成像技术的发展,尤其是弥散张量成像(d iffusion tensor,DTI)及血氧依赖水平磁共振成像(b lood ox-ygenation level dependent,BOLD)技术的日臻完善,在活体状态下显示活动的皮质区并无创跟踪脑内白质纤维,反映解剖连通性已成为可能。本文就功能磁共振BOLD、DTI联 相似文献
30.
马世科 《国外畜牧学(草食家畜)》2007,(2):9-11
绒山羊是青海海西州经济社会发展的基础性产业,本文从海西州资源、社会、经济等方面出发,结合绒山羊生物学特点,对当地绒山羊业发展提出一些问题和建议。 相似文献