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991.
992.
Marina Quartu Maria Pina Serra Annalisa Manca Paolo Follesa Maria Letizia Lai Marina Del Fiacco 《International journal of developmental neuroscience》2003,21(1):23-33
The immunohistochemical occurrence of the neurotrophin (NT) proteins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-4 (NT-4), and neurotrophin-3 (NT-3) is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. The NT-like immunoreactive structures were unevenly distributed and showed regional differences among cerebellar lobules and folia. NGF-, NT-4-, and NT-3-positive neuronal perikarya were observed in all specimens examined. At variance with the other neurotrophins, the BDNF antiserum labelled neuronal cell bodies only in newborn life and infancy, as well as extensive nerve fibre systems, whose density increased with age. The NT-antibodies, tested by Western blot on human cerebellum homogenates, revealed immunoreactive bands corresponding to proteins of heterogenous molecular weight. The results obtained provide a first demonstration of the tissue localization of the NTs in the human cerebellum from perinatal to adult age, thus suggesting their involvement in the development, differentiation and maintenance of the cerebellar connectivity. Codistribution of the four NTs or sets of them was observed in cortical and deep nuclei neurons. Multiple trophic roles for NTs, encompassing the classic target-derived and local mechanisms of support, are envisaged as significant in development, differentiation, and maintenance of the human cerebellar connectivity. 相似文献
993.
股骨粗隆间骨折是多发于老年人的一种常见骨折类型。患者高龄 ,多有明显的骨质疏松 ,愈后常遗留有髋内翻 ,下肢外旋及短缩畸形。非手术治疗时间长 ,患者长期卧床 ,易出现各种并发症造成治疗和康复困难。作者参照AO组织推荐的方法自 1996年5月 - 2 0 0 0年 12月在我院采用切开复位和闭合复位DHS内固定的方法治疗股骨粗隆间骨折患者 37例 ,取得良好的疗效。1 临床资料本组 37例 ,男 16例 ,女 2 1例 ;年龄 4 8~ 86岁 ,平均 69 4岁。右侧 18例 ,左侧 19例。根据股骨内侧骨皮质的状态 (Evans分型 ) ,即能支撑近端的股骨距是否完整 ,… 相似文献
994.
Efficacy of ondansetron and metoclopramide for preventing postoperative emesis following strabismus surgery in children 总被引:6,自引:0,他引:6
A double-blind, randomised, placebo-controlled trial was conducted to compare the efficacy of metoclopramide with the 5-HT3 antagonist, ondansetron, for the prevention of postoperative emesis in children undergoing elective strabismus surgery. None of the children received any premedication and a similar anaesthetic technique was used for all. Ondansetron 0.15 mg.kg−1 , metoclopramide 0.25 mg.kg−1 or saline placebo were administered following intravenous catheter placement. Episodes of emesis were recorded for the first 24 h for the intervals of 0–2, 2–6 and 6–24 h. The incidence of emesis in the first 24 h was observed to be 71.7% in the placebo group, 34.4% in the ondansetron group (p < 0.001) and 61.4% in the metoclopramide group (p = NS). The severity of vomiting was less in the ondansetron group as compared with metoclopramide (p < 0.01) and placebo (p < 0.001). Recovery room scores were comparable in all the groups. No serious side-effects were observed in the ondansetron group. We conclude that prophylactic ondansetron is effective and superior to metoclopramide in the prevention of postoperative emesis in children following elective strabismus surgery. 相似文献
995.
YOSHIKAZU MURAWAKI YUJIRO IKUTA YUUKO NISHIMURA MASAHIKO KODA HIRONAKA KAWASAKI 《Journal of gastroenterology and hepatology》1996,11(5):443-450
In order to elucidate collagen metabolism in hepatocellular carcinoma (HCC) tissue, we compared levels of different potential markers of collagen metabolism and plasma transforming growth factor-β1 in patients with HCC and in patients with liver cirrhosis. Serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1 in patients with HCC were significantly higher than those in patients with liver cirrhosis and increased with the size of the HCC tumour, whereas the serum levels of procollagen type III propeptide and type IV collagen 7S domain were similar in the two groups. In HCC, the increased plasma transforming growth factor-β1 levels were closely correlated with serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1. These findings suggest that, in HCC tissue, the intracellular biosynthesis of collagen is enhanced, whereas the secretion of procollagen is disturbed and the degradation of collagen is suppressed by the excess production of the tissue inhibitor of metalloproteinase-1. The results also suggest that plasma transforming growth factor-β1 plays an important role in the altered metabolism of collagen in HCC. 相似文献
996.
本实验应用二十一种抗人白细胞分化抗原的单克隆抗体。通过ABC(avidin-biotin peroxidase complex)免疫酶标方法对十二例淋巴细胞白血病病人进行了免疫表型分析。提示单克隆抗体在淋巴细胞白血病病人的临床分型、治疗及预后估计上很有意义。粒、淋双表达白血病其本质不明,因而治疗上至今还没有一个理想的方案。 相似文献
997.
A comparison of the effects of omeprazole and ranitidine on gastric secretion in women undergoing elective Caesarean section 总被引:2,自引:0,他引:2
This study compares the efficacy of omeprazole and ranitidine at reducing gastric secretion in obstetric patients. Sixty-five women scheduled to undergo elective Caesarean section under general anaesthesia were randomly allocated to receive either omeprazole 40 mg or ranitidine 150 mg orally at 2200 hours the night before and at 0600 hours on the morning of surgery. Intragastric pH and volume were measured immediately after induction of anaesthesia and on completion of surgery. All patients had gastric aspirates less than 25 ml. None of the omeprazole group had an aspirate of pH less than 3.5. Six patients (19%) in the ranitidine group had aspirates of pH less than 3.5, a significant difference from the omeprazole group (p less than 0.05). Of these six, two (6%) had aspirates of pH less than 2.5. Hence this study showed that omeprazole was more effective and consistent than ranitidine at maintaining gastric pH greater than 3.5. 相似文献
998.
M. M. Rasulov I. G. Kuznetsov R. G. Shakirova A. G. Zabozlaev A. A. Belousov M. G. Voronkov 《Bulletin of experimental biology and medicine》1993,115(1):73-75
Translated fromByulleten' Experimental'noi Biologii i Meditsiny, Vol. 115, No. 1, pp. 69–71, January, 1993 相似文献
999.
Isao Hamamoto Shunichi Takaya Satoru Todo Oscar Bronsther Shiro Fujita Thomas M. Van Gulik Kenjiro Nakamura William Irish Thomas E. Starzl 《Transplant international》1994,7(2):89-95
Sixty-eight primary liver grafts were analyzed to see whether adenine nucleotides (AN: ATP, ADP, and AMP) or purine catabolites (PC: adenosine, inosine, hypoxanthine, and xanthine) of tissue or effluent can predict primary graft nonfunction. AN, PC, and nicotinamide adenine dinucleotide, oxidized form (NAD+) of the tissue before (pretransplant) and after graft reperfusion (post-transplant) and of the effluent were analyzed. The graft outcome was classified into two groups (group A: successful, n=64; group B: primary nonfunctioning, n=4). No significant differences were observed in pretransplant measurements between groups A and B, whereas ATP, ADP, total AN, total AN+total PC (T) and NAD+, in post-transplant tissues, were significantly higher in group A. Xanthine in the effluent was significantly higher in group B than in group A. ATP, ADP, total AN, T, and NAD+ in post-transplant tissue were significantly associated with primary graft nonfunction by logistic regression analysis. 相似文献
1000.
THE PHYSIOLOGY OF PRE-ECLAMPSIA 总被引:2,自引:0,他引:2
Mark A. Brown 《Clinical and experimental pharmacology & physiology》1995,22(11):781-791
1. Pre-eclampsia is a multisystem disorder of human pregnancy with a genetic predisposition. It occurs more commonly in first pregnancies and primarily affects maternal renal, cerebral, hepatic and clotting functions while elevating blood pressure. The foetus is affected through placental insufficiency arising from abnormal ‘placentation’, that is, failure of adequate trophoblast invasion of maternal vasculature, and possibly from abnormal autacoid production. 2. Pre-eclampsia is caused by the placenta; delivery of the placenta is the only known cure. Its manifestations are considered secondary to organ hypoperfusion which arises as a result of vasoconstriction, intravascular coagulation and reduced maternal blood volume. 3. Current hypotheses propose that pre-eclampsia is due to widespread maternal endothelial cell damage, perhaps secondary to a cytotoxic factor released by the placenta. This hypothesis has gained wide acceptance, but scientific evidence is lacking. 4. Defining the abnormal balance of vasoactive factors in pre-eclampsia has proved a difficult task. There is enhanced pressor reactivity to infused angiotensin 11 (AII) despite reduced plasma concentrations of AII, renin and aldosterone. Prostacylclin production appears reduced, and the balance of thromboxane/prostacyclin favours vasoconstriction and platelet aggregation. There is no convincing evidence for enhanced endothelin or reduced nitric oxide production. Plasma concentrations of atrial natriuretic peptide are paradoxically elevated in the face of plasma volume contraction. An intriguing observation, which remains unexplained, is why some vascular beds are affected predominantly in one patient (eg. hepatic ischaemia) while another has a similar degree of hypertension but involvement of a different organ system (eg. renal insufficiency yet normal liver function). 5. Volume homeostasis is disturbed with redistribution of intravascular volume to the interstitial fluid space due to increased capillary permeability and in some cases reduced plasma oncotic pressure. This redistribution is not always clinically apparent as peripheral oedema. Whether this change in volume is compensated for by venoconstriction and maintenance of adequate cardiac output is undetermined. 6. Improved understanding of the pathophysiology of pre-eclampsia is necessary to allow better clinical management of this serious disorder. 相似文献