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81.
The renal circulation of patients with essential hypertension and renovascular hypertension was evaluated using 99mTc-DTPA. The first renal peak count (the first Cmax; FCmax), time phase distribution (the first Tmax; FTmax), and blood velocity (the FCmax/FTmax) were calculated by digital imaging. This yields a visual image of the renal circulation. We consider that the increase in the renal first pass blood flow in patients with essential hypertension is best observed pixel by pixel. The FCmax and FCmax/FTmax images before and after treatment by percutaneous transluminal renal angioplasty in patients with renovascular hypertension clearly show its therapeutic effect. The FI technique, therefore, has the advantage that it can be performed at the same time as the conventional routine examinations of renal function. This makes it very useful clinically.  相似文献   
82.
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI.  相似文献   
83.
Changes in the diffusion constant of water during reversible brain ischemia and cardiac arrest were monitored with a 10-s time resolution. Results (five cats, three rats) indicate that these changes are reversible and that the bulk of the changes are not caused by temperature or motion related to brain pulsations and blood flow. The rapid time course of the changes corresponds to the known time course for changes in energy state, signal transduction, and ionic homeostasis.  相似文献   
84.
We evaluated the effects of allogeneic bone marrow stromal cell treatment of stroke on functional outcome, glial–axonal architecture, and immune reaction. Female Wistar rats were subjected to 2 h of middle cerebral artery occlusion. Rats were injected intravenously with PBS, male allogeneic ACI – or syngeneic Wistar –bone marrow stromal cells at 24 h after ischemia and sacrificed at 28 days. Significant functional recovery was found in both cell-treated groups compared to stroke rats that did not receive BMSCs, but no difference was detected between allogeneic and syngeneic cell-treated rats. No evidence of T cell priming or humoral antibody production to marrow stromal cells was found in recipient rats after treatment with allogeneic cells. Similar numbers of Y-chromosome+ cells were detected in the female rat brains in both groups. Significantly increased thickness of individual axons and myelin, and areas of the corpus callosum and the numbers of white matter bundles in the striatum were detected in the ischemic boundary zone of cell-treated rats compared to stroked rats. The areas of the contralateral corpus callosum significantly increased after cell treatment compared to normal rats. Processes of astrocytes remodeled from hypertrophic star-like to tadpole-like shape and oriented parallel to the ischemic regions after cell treatment. Axonal projections emanating from individual parenchymal neurons exhibited an overall orientation parallel to elongated radial processes of reactive astrocytes of the cell-treated rats. Allogeneic and syngeneic bone marrow stromal cell treatment after stroke in rats improved neurological recovery and enhanced reactive oligodendrocyte and astrocyte related axonal remodeling with no indication of immunologic sensitization in adult rat brain.  相似文献   
85.
目的:利用血氧水平依赖法(BOL D)成像对患者脑胶质瘤并可能累及脑皮层功能区的患者进行功能磁共振成像(f MRI)检查,有助于外科治疗方案的制定,以提高手术的成功率和治愈率,避免重要脑功能中枢受到损伤。方法:对12例患有脑胶质瘤的患者用双手对指刺激的方法实行动态MR脑功能成像,共计5 0个动态,每次10个动态,18个层面,扫描时间为15 9s,分别间隔以等时间的静息期,检测感兴趣区正相关系数。结果:12例患者的图像采集满意,激活区均激活边缘系统,丘脑区,激活的脑功能区包括初级和次级躯体感觉区,尤以脑胶质瘤对侧激活最为显著(8例) ,同侧也有部分激活(4例)。结论:左右手对指激活特定的脑功能区,表明患者今后的恢复功能可能是对侧功能的代偿。这对外科制定手术方案,恢复的评估以及避免脑神经功能区的损伤有一定的指导意义。  相似文献   
86.
Many initial studies related to identification of the boundaries and structural components, nuclei, tracts and interconnections of the hypothalamus, this continues. Early interest also focused on hypothalamic control of somatic activities and autonomie nervous system functions. During the present century chiefly, interest has developed in the hypothalamus and control of water balance, thirst, water retention and loss (diabetes insipidus and polydipsia). Its role in control of metabolism, body weight (obesity), and the regulation of body temperature has attracted the attention of physiologists for many years. Others have studied hypothalamic regulation of sex and reproductive phenomena. The hypothalamus is now attracting much attention because of its production of neuroendocrine secretions and role in control of the endocrine system. Physiologists realized very early that the hypothalamus is involved in emotional expression, in reaction to stress and adaptive adjustments. Its involvement in disease states and resistance thereto and in determining the nature of behavior has now been recognized as a matter of great importance. The origins of all these interests are reviewed.  相似文献   
87.
Zusammenfassung Den Vorteilen einer osteosynthetischen Versorgung einer Fraktur mit sofortiger Aufnahme seiner Funktion, stehen die aus der Literatur bekannten Komplikationen gegenüber. Diese und unsere eigenen unbefriedigenden Ergebnisse nach der operativen Versorgung von Radiusköpfchenfrakturen ließen uns zu einer prospektiven randomisierten Studie einer primär funktionellen Behandlung unter Verzicht auf eine äußere oder innere Stabilisierung greifen. Seit Dezember 1991 haben wir im UKH-Graz bis einschließlich Dezember 1992 insgesamt 70 Patienten nach einem strikten Behandlungskonzept, unter Zuhilfenahme der Computertomographie zur Verlaufsbeobachtung versorgt. Die in 91% der Fälle als sehr gut and gut einzustufenden Frühergebnisse sowie das fehlende Auftreten einer, wie bei operativer Versorgung möglichen Komplikation, ebenso die zusätzlich deutlich frühere Arbeitsfähigkeit bzw. deutlich kürzere, wenn auch aufwendigere Behandlungszeit, lassen uns diese Verfahren nicht nur in unserem Hans weiterführen, sondern können wir auch weiter empfehlen.
Experience with internal fixation of fractures of the head of the radius
The advantages of internal fixation of fractures, with the possibility of immediate resumption of the function of the fractured bone, are in contrast to the well-known complications described in the literature. These complications and our own unsatisfactory results after surgical treatment of fractures of the head of the radius induced us to carry out a randomized prospective study of primary functional treatment of such fractures without external or internal stabilization. From December 1991 through December 1992, a total of 70 patients were treated according to a strict treatment protocol at the Graz Hospital for Accident Surgery, and CT was used for observation of the healing process. The positive early results, which in 91% of all cases were classified as very good or good, the lack of complications that sometimes follow surgical treatment, the markedly earlier recovery of the patient's working capacity, and the clearly shorter — albeit somewhat more expensive — treatment period required have led us to continue using this method at our hospital and also to recommend its use elsewhere.
  相似文献   
88.
目的探讨脑利钠肽(BNP)在评价功能性单心室患者行全腔静脉-肺动脉连接术(TCPC)后心功能中的价值及其意义。方法选择2004年4~11月间连续在我科随访的TCPC后患者11例(TCPC组),男7例,女4例;年龄8.2±4.1岁;随访时间2.1±1.6年。按照改良R oss标准对临床心功能评分。采集外周静脉血3m l,用酶标免疫法测定血浆BNP浓度。其中6例同期用磁共振成像(M R I)测定心功能,对BNP做相关因素分析。9人健康儿童作为正常对照(对照组)。结果(1)TCPC组血浆BNP水平为400pg/m l(IQR 200-690),较对照组的110 pg/m l(IQR 90-190)增高(P=0.003);(2)M R I测定结果:TCPC组6例患者舒张期末容量指数为65.76±8.65 m l/m2,收缩期末容量指数为31.90±6.36 m l/m2,心搏出量指数为39.09±11.76 m l/m2,射血分数(EF)为0.52±0.06,心脏指数(C I)为2.38±0.58 L/m in.m2,心肌质量指数为103.49±21.57 g/m2,心肌质量/心室舒张期末容量为1.57±0.24;(3)TCPC组BNP水平与手术时年龄呈明显正相关(r=0.632,P=0.041);BNP水平与上述M R I指标、R oss评分、性别、年龄、脉搏血氧饱和度(SpO2)及主心室类型等因素无关。结论TCPC后近2年神经内分泌系统仍处于应激状态,BNP增高可能与TCPC后特有的血流动力学状态有关;血浆BNP水平不能作为正确评估TCPC后心功能状态的指标。  相似文献   
89.
90.
Lactate dehydrogenase (LDH, EC 1.1.1.27) catalyzes an exchange reaction between pyruvate and lactate. It is demonstrated here that this reaction is sufficiently fast to cause a significant magnetization (saturation) transfer effect when the 13C resonance of pyruvate is saturated by a continuous-wave (CW) RF pulse. Infusion of [2-(13)C]glucose was used to allow labeling of pyruvate C2 at 207.9 ppm to determine the pseudo first-order rate constant of the unidirectional lactate-->pyruvate flux in vivo. During systemic administration of GABAA receptor antagonist bicuculline, this pseudo first-order rate constant was determined to be 0.08+/-0.01 s-1 (mean+/-SD, N=4) in halothane-anesthetized adult rat brains. In 9L and C6 rat glioma models, the 13C saturation transfer effect of the LDH reaction was also detected in vivo. Our results demonstrate that the 13C magnetization transfer effect of the LDH reaction may be useful as a novel marker for utilizing noninvasive in vivo MRS to study many physiological and pathological conditions, such as cancer.  相似文献   
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