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51.
Manolo Piccirilli Jacopo Lenzi Catia Delfinis Guido Trasimeni Maurizio Salvati Antonino Raco 《Child's nervous system》2006,22(10):1332-1337
Case reports The authors report their experience about three children (two girls, one boy; average age 1.6 years) with a spontaneous regression of optic gliomas. All of them had a previous diagnosis of neurofibromatosis type 1 (NF 1). None of them underwent surgery or biopsy nor received chemotherapy or radiotherapy. The complete regression was documented by MRI scans performed during a mean follow-up of 6.3 years.Literature review Moreover, the authors analyze the features of the 16 cases previously reported in English literature of spontaneously regressed optic gliomas with an overview of the different therapeutic strategies. The knowledge that this kind of tumor, particularly in young patients, may regress is important in the decision of the best therapeutic approach. 相似文献
52.
血清CA125检测对子宫内膜异位症的临床诊断价值 总被引:2,自引:0,他引:2
巫云 《中国交通医学杂志》2003,17(5):535-536
目的 :探讨血清CA12 5测定对术前子宫内膜异位症的诊断价值。方法 :99例子宫内膜异位症经腹手术前测定CA12 5水平 ,并与 90例作对照比较。结果 :子宫内膜异位症CA12 5阳性率 >3 5U /ml,为 5 7.5 7% ,对照组为 8.88% (P <0 .0 1)。内膜异位囊肿高于卵巢囊肿 (P <0 .0 1) ,子宫腺肌病高于子宫肌瘤 (P <0 .0 5 )。结论 :血清CA12 5测定对子宫内膜异位症有较理想的诊断价值 ,对异位囊肿与卵巢囊肿 ,子宫腺肌病与子宫肌瘤有鉴别意义 相似文献
53.
Taurine has been proposed as an inhibitory neurotransmitter or neuromodulator in the vertebrate central nervous system. Within the spinal cord, taurine has been shown to have a direct inhibitory effect on spinal neurons and to have a selective antinociceptive effect on chemically induced nociception. Although sufficient data exists to suggest that taurine plays a neurotransmitter or neuromodulatory role in the spinal cord, it is not known whether this amino acid is present in axon terminals nor if this amino acid has a unique pattern of distribution within spinal tissue. To address these questions a monoclonal antibody against taurine was employed to localize taurine-like immunoreactivity in the dorsal horn of the rat spinal cord by using both light and electron microscopic techniques. Taurine-like immunoreactivity was most dense and most prominent in laminae I and II of the dorsal horn. A moderate amount of immunoreactivity was also present in laminae VIII and IX and X while the remaining laminae were only lightly stained. In laminae I and II taurine-like immunostaining was evident within neuronal cell bodies, dendrites, myelinated and unmyelinated axons, axon terminals, and astrocytes and their processes. Cell counts of these two laminae indicated that approximately 30% of neuronal perikarya at the C2 level, 52% of neuronal perikarya at the T6 level, and 18% of neuronal perikarya at the L2 level of the cord exhibited taurine-like immunoreactivity. With preembedding diaminobenzidine staining, approximately 20% of the axons examined in laminae I and II were found to be immunoreactive for taurine. Using postembedding immunogold staining in combination with quantitative procedures, the highest densities of gold particles were found in axon terminals containing pleomorphic vesicles and forming symmetrical synapses (36.8 particles/micron2), in a subpopulation of myelinated axons (34.2 particles/micron2), in a subpopulation of neuronal dendrites (32.6 particles/micron2), and in capillary endothelial cells (39.8 particles/micron2). Moderate labeling occurred in astrocytes (20.9 particles/micron2) and neuronal perikarya (18.7 particles/micron2). The localization of taurine to presumptive inhibitory axon terminals provides anatomical support for the hypothesis that taurine may serve an inhibitory neurotransmitter role in the superficial dorsal horn of the spinal cord. On the other hand, its localization to astrocytes and endothelial cells within both the dorsal ventral horns implies that it serves other nonneuronal functions as well. 相似文献
54.
The influence of partial gastrectomy on biochemical parameters of bone metabolism and bone density 总被引:2,自引:0,他引:2
Dr. H. Resch P. Pietschmann B. Pernecker E. Krexner R. Willvonseder 《Journal of molecular medicine (Berlin, Germany)》1992,70(5):426-429
Summary Since it has been suggested that gastric resections are followed by changes in bone metabolism, the aim of our study was to determine the biochemical parameters of bone metabolism and radial and lumbar bone density in 15 male ulcus patients treated by partial gastrectomy (Billroth II). Comparing the data with those of a corresponding control group, the lumbar bone density measured by quantitative computed tomography was statistically significantly lower (P < 0.04) in the patient group, whereas the peripheral bone mass of the distal part of the nondominant forearm measured by single-photon absorptiometry showed no statistically significant difference. In addition, a marked increase in alkaline phosphatase (P < 0.002) and urinary excretion of hydroxyproline (P < 0.003) was found in the gastrectomy group, whereas the 25-hydroxy-vitamin D levels were found to be significantly decreased (P < 0.04). Osteocalcin, a biochemical marker for osteoblast activity, and the carboxy-terminal propeptide of type I procollagen (PICP), a marker of collagen formation, were slightly but not significantly higher in gastrectomy-treated patients. The serum parathyroid hormone levels were similar in both groups. As none of the patients had any radiologic evidence of osteopenia, the changes in biochemical parameters of bone metabolism and bone mass in patients who had undergone partial gastrectomy could be a marker of latent bone loss.Abbreviations DPA/SPA
dual/single-photon absorptiometry
- BMD
bone mineral density
- QCT
quantitative computed tomography
- PICP
carboxy-terminal propeptide of type I procollagen
- 250HD3
25-hydroxy-vitamin D
- iPTH
parathyroid hormone
- OC
osteocalcin
- BMC
bone mineral content 相似文献
55.
Phase I Study of Paclitaxel by Three-hour Infusion: Hypotension Just after Infusion Is One of the Major Dose-limiting Toxicities 总被引:4,自引:0,他引:4
Tomohide Tamura Yasutsuna Sasaki Yutaka Nishiwaki Nagahiro Saijo 《Cancer science》1995,86(12):1203-1209
The primary objectives of this study were to determine the maximum tolerated dose (MTD) of paclitaxel administered by 3-h infusion to patients with solid tumors, and to characterize the pharmacokinetics of a 3-h infusion in comparison with those of a 24-h infusion. Twenty-seven patients each received one of six levels of paclitaxel, 105, 135, 180, 210, 240 and 270 mg/m2 , with premedication. Two patients given 240 mg/m2 and one patient given 270 mg/m2 unexpectedly had grade 3/4 hypotension just after finishing the paclitaxel infusion. Peripheral neuropathy was also dose-limiting at 270 mg/m2 . Although granulocytopenia was significantly less severe than with a 24-h infusion, more than half of the patients experienced grade 4 toxicity at doses of 240 or 270 mg/m2 . Severe hypersensitivity reactions (HSRs) were not observed. Pharmacokinetic studies using high performance liquid chromatography demonstrated proportionally greater increases in the peak plasma concentration and area under the curve, and decreases in clearance and volume of distribution with increasing dose, suggesting non-linear pharmacokinetics of paclitaxel when given by 3-h infusion. The MTD of paclitaxel given as a 3-h infusion was determined to be 240 mg/m2 with dose-limiting toxicities of granulocytopenia, peripheral neuropathy and hypotension. Hypotension just after infusion, induced by 3-h infusion of paclitaxel, is a new observation which has not been reported previously. The recommended dose for phase II study is 210 mg/m2 . Although hypotension was observed as an unexpected toxic effect, paclitaxel could be administered safely over 3 h with premedication and proper monitoring, resulting in reduced myelotoxicity and with no increase in the incidence of HSRs as compared with a 24-h infusion. 相似文献
56.
PIERRE VULLIEMIN ALESSANDRO DEL BUFALO JURG SCHLAEPFER MARTIN FROMER LUKAS KAPPENBERGER 《Pacing and clinical electrophysiology : PACE》1994,17(8):1391-1398
Assuming that type I atrial flutter is a macroreentrant circuit, its cycle length should vary with the atrial dimensions. In order to test this hypothesis, flutter cycle length was measured while inducing atrial volume and pressure changes by postural and pharmacological means in seven patients undergoing a therapeutic programmed stimulation for type 1 atrial flutter conversion. Right atrial volume was estimated from B-mode echocardiography data. Basal values were compared with those obtained during inspiration, expiration, Valsalva maneuver, negative tilt (head down), and positive tilt (head up) with 0.8–1.6 mg p.o. nitroglycerin. The right atrial size increased slightly from 17.8 to 18.3 cm2 (P = 0.04) during the pressure load induced by negative tilt (+ 3 mmHg), with a corresponding lengthening of the flutter cycle length from 228 to 233 msec (P = 0.02). Similarly, pressure unloading of -2 mmHg by positive tilting and nitrates was accompanied by a decrease in right atrial size to 16.6 cm2 (P = 0.04), with a corresponding decrease in cycle length from 228 to 219 msec (P = 0.03). Respiratory maneuver yielded similar results with an inspiratory cycle lengthening, expiratory shortening, and further shortening during Valsalva maneuver. These experiments demonstrate a direct relation between cycle length and atrial volume in human type I atrial flutter. They underline the importance of the right heart preload and atrial size for the electrophysiological characteristics of type I atrial flutter. Beside its fundamental interest, this finding is important for the understanding of the mechanism of maintenance and therapeutic responses of this common arrhythmia. 相似文献
57.
人口腔鳞癌演变过程中HLA-DR表达改变的研究 总被引:3,自引:0,他引:3
目的 :观察HLA DR在口腔鳞癌发生、发展过程中表达的改变并探讨其临床意义。方法 :采用免疫组织化学的方法检测了 2 6例正常口腔黏膜、8例口腔黏膜白斑、3 2例口腔鳞癌原发灶及 15例颈淋巴结转移灶标本内HLA DR的表达。结果 :口腔鳞癌原发灶与正常口腔黏膜HLA DR的表达存在有显著性差异 (P <0 .0 5) ,其余各组间未见有此差异 ;鳞癌原发灶HLA DR的表达除与局部淋巴细胞浸润有显著性关系外与其余各临床病理资料间均无明显关系。结论 :HLA DR在口腔鳞癌细胞中存在有表达异常增高的现象但并不能作为独立的预后判断因素 相似文献
58.
病毒性心肌炎心肌肌钙蛋白Ⅰ检测的临床意义 总被引:1,自引:0,他引:1
目的:对病毒性心肌炎患儿血中肌钙蛋白I(cTn I)含量进行检测,探讨与临床的关系。方法:采用放射免疫法对24例病毒性心肌炎患儿血中cTn I进行定量检测,同时检测血清心肌酶谱的改变情况,并就两种指标进行相关性探讨。结果:病毒性心肌炎患儿血中cTn I含量明显增高(4.5±2.2 )vs(2.3±0.3)ng/ml,P<0.01),并与CKMB,LDH_1的含量呈明显的正相关。结论:cTnl I是诊断病毒性心肌炎的敏感指标,可以反映出心肌受损的程度。 相似文献
59.
目的:研究内皮素(ET-1)、P-选择素、肌钙蛋白I(CTn1)在急性心肌梗死(AMI)和不稳定性心绞痛(UA)中的意义,方法:用放射免疫法测ET-1,流式细胞术测定P-选择素,Access化学发光测CTn1,共检测23例AMI患、21例UA患及28例健康对照。结果:AMI组的ET-1、P-选择素、CTn1值均显高于对照组(P<0.05-0.005);UA组的ET-1、P-选择素显高于对照组(P<0.05);UA组的CTn1与对照组差异无显性(P>0.05);UA组的P-选择素、CTn1显低于AMI组(P<0.05)。多元回归分析发现P-选择与CTn1相关,相关系数r=0.404,P<0.01。结论:ET-1、P-选择素是检测血栓前状态的敏感指标。 相似文献
60.
Elena del Olmo Carmen del Arco Alvaro Díaz Julio Pascual Guadalupe Mengod José M. Palacios Angel Pazos 《The European journal of neuroscience》1996,8(1):53-60
The pattern of pre- and postnatal appearance of 5-HT1D receptors throughout the different areas of the human brain was studied by quantitative in vitro autoradiography, using [125 I]GTI (serotonin O -carboxymethyl-glycyl-[125 I]tyrosinamide) as a ligand. The anatomical distribution of 5-HT1D receptors in neonatal, infant and children's brain was in good agreement with that observed in the adult, the basal ganglia and substantia nigra being the most intensely labelled areas. The development of these receptors throughout the human brain was mainly postnatal: low densities of [125 I]GTI binding sites were observed at the fetal/neonatal stage in most regions analyzed, in contrast with the high levels of labelling found in infant and children's brains. Indeed, in a number of regions, including the globus pallidus, substantia nigra and visual cortex, a peak of overexpression of 5-HT1D receptors was observed in the first decade of life. Such overexpression could support a regulatory role for 5-HT1D receptors in advanced periods of the CNS developmental process. Our results also indicate that the administration of drugs acting on 5-HT1D receptors during the early postnatal period of life could result in modifications of their properties, as these receptors are already functional in this period. 相似文献