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131.
Previous exposure to a dopaminergic agonist (priming) strongly potentiates contralateral turning behaviour in response to D1 and D2 agonists in unilaterally 6-hydroxydopamine-lesioned rats. In order to study the influence of priming on the behavioural interaction of D1 and D2 receptors, we examined the effect of selective D1 and D2 receptor blockade on the contralateral turning induced by the mixed D2/D2 agonist apomorphine in drug-naive and primed 6-hydroxydopamine-lesioned rats. In drug-naive rats, apomorphine induced a dose-related, apparently monophasic rotation curve. Administration of selective D1 (SCH 23390) or D2 (raclopride) antagonists abolished the contralateral turning induced by 0.1 mg/kg of apomorphine and partially inhibited that induced by 0.5 mg/kg. In primed rats low doses of apomorphine (0.05 mg/kg) induced an apparently monophasic contralateral turning which was reduced by D1 receptor blockade and completely abolished by D2 receptor blockade; a higher dose of apomorphine (0.1 mg/kg) instead elicited a biphasic (two-peak) pattern of rotation. After this dose of the agonist, blockade of D1 or D2 receptors abolished the second peak of rotation but, while D1 blockade reduced the total number of turns, D2 blockade failed to do so. Quantitative analysis of the interaction between D1 and D2 receptors in the overall turning effect, as well as in the time-course of turning behaviour, indicates that D1 and D2 receptors interact not only positively but also negatively. After higher doses of apomorphine, both negative and positive interactions take place sequentially during the time-course of apomorphine action and provide a clue for explaining the two-peak pattern of rotation observed after apomorphine in rats previously exposed to the drug. 相似文献
132.
P L Di Patre 《Medical hypotheses》1991,34(2):165-170
A theory is presented here in the attempt to explain why Alzheimer's disease (AD) primarily affects areas of the human brain that have been acquired recently in phylogenesis. Disturbances in cytoskeletal function are proposed to play a fundamental role in triggering the sequence of pathologic events leading to the occurrence of AD-related histopathological markers and to the degeneration and death of neurons. These deficits are supposed to occur more likely in neuronal populations that possess a high degree of plasticity, the substrate of memory functions, and that constitute, in fact, the phylogenetically new telencephalic regions of the human brain. 相似文献
133.
134.
Nutritional follow-up after total gastrectomy 总被引:1,自引:0,他引:1
135.
Anna Plachcinska Jacek Kusmierek Maciej Kosmider Malgorzata Bienkiewicz Julian Liniecki 《European journal of nuclear medicine and molecular imaging》1995,22(3):193-200
A quantified evaluation of planar cardiac perfusion scintigrams (the objective of the study), obtained using technetium-99m methoxyisobutylisonitrile (MIBI) was performed on the basis of an analysis of circumferential profile curves, representing the perfusion as seen in three typical projections. The analysis involved the curves obtained both at rest and after stress, and was based on a comparison of their shape (trend) with the normal trend (normative evaluation). The latter was obtained by means of an original method of iterative fitting of individual curves into the database. The base consisted of curves recorded in 53 patients (separately in males and females) with normal perfusion of the left ventricle (group I, the reference group). A group of 90 patients suspected of having coronary artery disease (group II) was subdivided into two subgroups on the basis of coronary arteriography: (a) those with and (b) those without critical stenosis of at least one artery. Profile curves characterising the LV perfusion were obtained at rest and after stress. Defects of perfusion were quantified by comparison of individual curves with the normal trends. By means of multivariate analysis it was demonstrated that vectors of mean values characterising the scintigraphically assessed defects of LV perfusion in the two subgroups of group II differed very significantly (P<10–5). Applying methods of discriminant analysis, a classification of patients from group II was performed into those with probable defects of perfusion and those free of such defects. The sensitivity, specificity and accuracy of diagnosis of coronary ischaemia, based on quantified planar99mTc-MIBI scintigraphy, reached 86%, 87% and 87%, respectively. 相似文献
136.
甘肃省1995年共报告15岁以下儿童急性弛缓性麻痹(AFP)病例90例,发病率为1.32/10万。省脊髓灰质炎(脊灰)实验室收到AFP病例的粪便标本共79例,占88%;双份合格粪便标本采集率为68%(61/90);粪便标本7天内送省脊灰实验室的占65%(52/79)收到粪便标本后7天内分离培养的占89%(70/79);分离培养结果及时报告率为87%(69/79)。病毒分离阳性率13.92%(11/79),其中脊灰病毒(PV)Ⅱ型5株,Ⅲ型1株,非脊灰肠道病毒(NPEV)5株。收到AFP病例密切接触者粪便标本3l8份,病毒分离阳性率5.66%(18/318),其中PVⅡ型8株,NPEV10株。全部送检粪便标本NPEV分离率3.78%(15/397)。所分离的PV均为疫苗株,且Ⅱ型居多。 相似文献
137.
Daily nutrient intake represents a modifiable determinant of nutritional status in chronic haemodialysis patients. 总被引:2,自引:0,他引:2
Vincenzo Bellizzi Biagio R Di Iorio Vincenzo Terracciano Roberto Minutolo Carmela Iodice Luca De Nicola Giuseppe Conte 《Nephrology, dialysis, transplantation》2003,18(9):1874-1881
BACKGROUND: In maintenance haemodialysis patients, daily food intake is changeable; however, its relationship with nutritional status is unexplored. This study aimed to evaluate the isolated, long-term effect of daily nutrient intake on nutritional status in haemodialysis patients. METHODS: We performed a prospective 1-year controlled study in 27 chronic haemodialysis patients, without recognized risk factors for malnutrition. Each day for 1 week, four times in the year, we measured protein nitrogen appearance, and assessed dietary protein (DPI) and energy (DEI) intake from dietary diaries. We compared the nutritional outcome of patients spontaneously reducing nutrient intake below the threshold of 0.8 g/kg body weight/day for DPI and 25 kcal/kg body weight/day for DEI during the week (LOW, n = 8), with controls at adequate nutrient intake (CON, n = 19). An interventional 6-month study was then carried out in LOW to verify the cause-effect relationship. RESULTS: All patients showed a day-by-day reduction of whole nutrient intake during interdialytic period, which was mostly relevant in the third interdialytic day (L3). During the 1-year study, even in the presence of adequate dialysis dose and normal inflammatory indexes, body weight (68.0 +/- 5.5 to 65.8 +/- 5.9 kg), serum albumin (3.96 +/- 0.07 to 3.66 +/- 0.06 g/dl) and creatinine (9.2 +/- 1.1 to 8.1 +/- 0.7 mg/dl) significantly decreased in LOW but not in CON. Diaries evidenced in LOW a reduced number of meals at L3 that was explained by the fear of excessive interdialytic weight gain. During the interventional study, daily DPI and DEI increased at L3; this was associated with a significant increment of body weight, and serum albumin and creatinine levels. CONCLUSIONS: In maintenance haemodialysis patients the persistent, marked reduction of daily nutrient intake, even if limited to a single day of the week, is an independent determinant of reversible impairment of nutritional status. 相似文献
138.
Ultrafiltration and solute transport during 60-min peritoneal dialyses of normal rabbits with intraperitoneal administration of phosphatidylcholine were compared to control values. The ultrafiltration rate of 0.27 mL/Kg/min did not increase when phosphatidylcholine was added. This agent had no effect on the ultrafiltration coefficient, sodium mass transport or solute clearances. Previously reported beneficial results with this agent could be due to repletion of a deficiency or an effect of the organic solvent. More studies of safety and efficacy of phosphatidylcholine are warranted before widespread clinical use. 相似文献
139.
Sir, We are writing to provide some clarifications on the EditorialComment by Drüeke et al. [1]. We would have been happyto provide these very same clarifications had we been fairlyinvited to do so before the publication of the article. First of all, we would like to 相似文献
140.