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排序方式: 共有6395条查询结果,搜索用时 15 毫秒
111.
Johnston-Wilson NL Sims CD Hofmann JP Anderson L Shore AD Torrey EF Yolken RH 《Molecular psychiatry》2000,5(2):142-149
Severe psychiatric disorders such as schizophrenia, bipolar disorder and major depressive disorder are brain diseases of unknown origin. No biological marker has been documented at the pathological, cellular, or molecular level, suggesting that a number of complex but subtle changes underlie these illnesses. We have used proteomic technology to survey postmortem tissue to identify changes linked to the various diseases. Proteomics uses two-dimensional gel electrophoresis and mass spectrometric sequencing of proteins to allow the comparison of subsets of expressed proteins among a large number of samples. This form of analysis was combined with a multivariate statistical model to study changes in protein levels in 89 frontal cortices obtained postmortem from individuals with schizophrenia, bipolar disorder, major depressive disorder, and non-psychiatric controls. We identified eight protein species that display disease-specific alterations in level in the frontal cortex. Six show decreases compared with the non-psychiatric controls for one or more diseases. Four of these are forms of glial fibrillary acidic protein (GFAP), one is dihydropyrimidinase-related protein 2, and the sixth is ubiquinone cytochrome c reductase core protein 1. Two spots, carbonic anhydrase 1 and fructose biphosphate aldolase C, show increase in one or more diseases compared to controls. Proteomic analysis may identify novel pathogenic mechanisms of human neuropsychiatric diseases. 相似文献
112.
All sterilization and disinfection procedures for bone grafts are different in regard to influence of bone graft features, which may influence the function of different cell types. We used an in-vitro approach to assess the influence of bone matrix, which was sterilized or disinfected, on osteoblastic activities in-vitro by simulating a cell-transplant-interface. Primary bovine osteoblast cell cultures were established from periosteum. Bone graft specimens made of bovine cortical bone (O 15 mm, 300 microns thickness) were treated in 5 different ways: autoclaved, ethylene-oxide-sterilized, demineralized and low-temperature-plasma-sterilized (DEM-LTP), chemically sterilized (modified Tutoplast method), and 80 degrees C-temperature disinfected. The following cell function parameters were assayed: plating efficiency proliferation by measuring the DNA-content, and MTT-activity, soluble protein and extracellular matrix synthesis, alkaline phosphatase, and osteocalcin expression. All disinfected bone grafts were biocompatible with primary periosteal osteoblasts. Measured cell activities upon bone specimens showed better results than cells of the plastic surface control. The DEM-LTP-bone showed better results in comparison to other groups, and stimulated the proliferation and differentiation. 相似文献
113.
Matic G Hofmann D Winkler R Tiess M Michelsen A Schneidewind JM Hebestreit G Keysser M Müller W Kinze EM Ramlow W 《Artificial organs》2000,24(2):103-107
Elimination of IgG can be achieved by extracorporeal immunoadsorption (IA) based on specific binding to either staphylococcal protein A (Excorim) or sheep polyclonal antibodies directed against human IgG (Therasorb). In 602 analyzed sessions of IA, elimination of IgG was 60% through 80% depending on the treated plasma volume, with no significant difference between the mentioned systems. However, the decrease of IgM and IgA was approximately 50% in the anti-IgG compared to 20-40% in the protein A system. Plasma albumin concentration decreased by 20% in the anti-IgG system compared to 15% in the protein A system, and hemoglobin values increased by 2% in the anti-IgG system and decreased by 6% in the protein A system. In conclusion, a clinical relevance for these findings cannot be ruled out, and the individual choice might depend on the clinical situation and laboratory findings. 相似文献
114.
Martins K Ahrenholz P Matic GB Hofmann D Tiess M Winkler RE Ramlow W 《Artificial organs》2000,24(7):526-532
Release of microparticles into the blood during extracorporeal circulation must be kept low because of possibly serious acute and chronic adverse effects. Concentration and size distribution of microparticles were measured during simulated treatments (n = 7) on original equipment for 2 standard low-density lipoprotein (LDL) elimination procedures (DALI 750, Fresenius AG, St. Wendel, Germany and Liposorber, Kaneka Corporation, Osaka, Japan) and compared to hemofiltration solutions. For both systems as well as in hemofiltration solutions, the mean particle concentrations in 500 ml portions gathered from the efferent blood line stayed below 10% of pharmacopoeia standards for infusion solutions (United States Pharmacopoeia, European Pharmacopoeia) in all measured size classes. Although particle concentrations were comparable in all systems, the mean total number of particles > or =2 microm released per session was lowest in the DALI (167,000) compared to the Liposorber (465,000) and hemofiltration solutions (2,240,000). This was mainly due to different total processed blood volumes necessary to achieve the required LDL reduction. 相似文献
115.
Diagnostic imaging in femur head necrosis 总被引:9,自引:0,他引:9
Diagnosis of avascular necrosis (AVN) of the hip has been improved by the technical progress of imaging modalities during the last decade. For a long period, only plain radiographs had been available. Scintigraphy and computed tomography contributed to differential diagnosis and early detection of bone necrosis. In the meantime, MR imaging has gained special value in the evaluation of AVN. It is now the method of choice for early detection as well as for assessment in later stage disorders. Using the ARCO system, all imaging modalities and their diagnostic viability are described. Findings regarding the different stages of AVN are correlated to tissue-specific changes. 相似文献
116.
117.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
118.
Differential regulation of ciliary neurotrophic factor and its receptor in the rat hippocampus following transient global ischemia 总被引:3,自引:0,他引:3
To investigate a potential role of ciliary neurotrophic factor (CNTF) in transient global ischemia, we have studied the postischemic regulatory changes in the expression of CNTF and its receptor, the ligand-binding alpha-subunit (CNTFRalpha). Immunoblot analysis demonstrated CNTF levels were slightly upregulated already during the first day after ischemia and then increased markedly by more than 10-fold until 2 weeks postischemia. Immunoreactivity for CNTF became detectable 1 day after ischemia and was localized in reactive astrocytes. The intensity of the immunolabeling was maximal in CA1 during the phase of neuronal cell death (days 3-7 postischemia) and in the deafferented inner molecular layer of the dentate gyrus. Upregulation of CNTF expression was less pronounced in CA3 and absent in the stratum lacunosum moleculare and the outer molecular layer of the dentate gyrus and thus did not simply correlate with astroliosis as represented by upregulation of glial fibrillary acidic protein (GFAP). As shown by in situ hybridization, expression of CNTFRalpha mRNA was restricted to neurons of the pyramidal cell and granule cell layers in control animals. Following ischemia, reactive astrocytes, identified by double labeling with antibodies to GFAP, transiently expressed CNTFRalpha mRNA with a maximum around postischemic day 3. This astrocytic response was most pronounced in CA1 and in the hilar part of CA3. These results show that CNTF and its receptor are differentially regulated in activated astrocytes of the postischemic hippocampus, indicating that they are involved in the regulation of astrocytic responses and the neuronal reorganizations occurring after an ischemic insult. 相似文献
119.
Mäurer M Becker G Wagner R Woydt M Hofmann E Puls I Lindner A Krone A 《Acta neurochirurgica》2000,142(10):1089-1097
Summary ? Purpose. In this prospective study the results of multimodal postoperative neuro-imaging were related to the survival of patients
with high grade gliomas.
Methods. All 73 patients included underwent microsurgical tumour resection and had postoperative CT and transcranial sonography (TCS)
examinations. In addition, 35 of the 73 patients received an early postoperative MRI. Patients were followed up for at least
one year.
Findings. At the end of the 7 year study period 56 patients had died. The median survival time was 371 days. Survival rate was significantly
higher in patients with anaplastic astrocytomas and inpatients displaying complete tumour resection on MRI (log-rank-test,
p<0.05) or a small postoperative residual tumour bulk on TCS (log-rank-test, p<0.05). Cox proportional hazards model identified
histological tumour grade, postoperative Karnofsky index, complete resection based on MRI and small postoperative residual
tumour mass on TCS as independent predictors of survival.
Interpretation. This study demonstrates that early postoperative neuro-imaging has prognostic implications for the survival of patients with
high grade gliomas. According to our results postoperative imaging with MRI and TCS is a valuable prognostic with regard to
patient survival and should therefore be implemented in postoperative follow-up. It also helps to evaluate the efficacy of
adjuvant therapy. 相似文献
120.
目的观察再发性低血糖后脑内葡萄糖转运蛋白1(glucose transporter 1,GLUT1)及葡萄糖转运蛋白3(GLUT3)表达的变化,从而探讨无症状低血糖的发生机制。方法将80只15日龄野生型小鼠随机分为正常对照组及低血糖组,每组40只。低血糖组给予正规胰岛素腹腔注射3次,每次剂量为5U/kg,对照组注射等体积生理盐水。两组分别在最后1次注射后12、24、48及72 h处死小鼠取脑组织(每组每时间点10只),应用免疫组化方法观察小鼠脑内GLUT1及GLUT3表达的变化。结果低血糖后脑内微血管上GLUT1表达有增加趋势,皮质增加高于海马,72 h皮质GLUT1表达显著高于对照组;低血糖后48、72 h皮质及海马GLUT3表达均显著高于相应对照组。结论再发性低血糖后脑内GLUT1及GLUT3适应性增高,这种适应既能节省神经元的能量代谢,但也能削减神经元对低血糖的反应。 相似文献