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61.
P.W. Nathan 《Journal of the neurological sciences》1976,27(1):129-130
Cerebral blood flow (CBF) was measured by a 133Xe inhalation technique in 8 patients with chronic high spinal cord injuries. Six patients had a physiologically complete cervical cord transection and 1 subject had an incomplete C4–5 lesion but with evidence of interruption of sympathetic pathways. CBF and arterial blood pressure (BP) were measured in the supine position and then in the sitting, or feet up, position to produce a change of BP. In 4 patients CBF was measured during a suction manoeuvre applied to the lower half of the body to produce a fall of BP. There was no significant change of CBF in the patients during hypo- and hypertension. The response of CBF to hyperventilation for 5 min was measured in the supine position and did not differ significantly from that of 13 normal “control” subjects and 1 patient with a lesion at T2–3. It is concluded that the responses of the cerebral circulation to change of blood pressure and to hypocapnia are normal in patients with high spinal cord transection. The mechanisms involved in these responses are therefore independent of control via cervical sympathetic pathways. 相似文献
62.
63.
Sewards TV 《Neuropsychologia》2011,49(3):277-313
Since the discovery in 1996 that a region within caudal parahippocampal cortex subserves learning and recall of topographical information, numerous studies aimed at elucidating the structures and pathways involved in scene recognition have been published. Neuroimaging studies, in particular, have revealed the locations and identities of some of the principal cortical structures that mediate these faculties. In the present study the detailed organization of the system is examined, based on a meta-analysis of neuroimaging studies of scene processing in human subjects, combined with reviews of the results of lesions on this type of processing, single neuron studies, and available hodological data in non-human primates. A cortical hierarchy of structures that mediate scene recognition is established based on these data, and an attempt is made to determine the function of the individual components of the system. 相似文献
64.
Introduction
Injury to the surrounding vessel wall is one of the major reasons for failure of implantable medical devices. The surgical procedure itself or the altered flow conditions after implantation can cause damage to the vessel wall. This damage exposes tissue factor (TF), the initiator of the extrinsic pathway of coagulation. One approach to combat thrombosis is to use an anticoagulant on the surface of the device. The primary aim of this study is to develop a simplified physiologically relevant in vitro model of vessel wall injury to study the mechanisms by which immobilized recombinant tissue factor pathway inhibitor (rTFPI) effectively inhibits TF initiated thrombosis.Materials and methods
A two well chamber slide was used for the study. Fibroblasts were cultured on the upstream portion of the slide. Fibroblast cells stimulated with TNF-α acted as a source of surface TF. The downstream portion of the slide was coated with rTFPI. A mixture of FX, FVIIa and calcium was perfused over the slides to generate FXa. Effluent collected at the outlet was used to analyze the inhibition of this surface generated FXa by the rTFPI present downstream.Results and conclusions
Different shear rates and rTFPI densities were used to study this effect. In most cases rTFPI inhibited FXa generated upstream as a function of the wall shear rate and rTFPI dosage (surface density). This study shows the effectiveness of the surface bound inhibitor when FXa is generated from an upstream injury site and the bulk of FXa is near the wall. 相似文献65.
Introduction
Serotonin is secreted from platelets at sites of endothelial injury, where it promotes thrombogenic reactions. Serotonin is reported to be associated with not only coronary artery disease but also cardiac events.Materials and Methods
We studied 33 patients with stable effort angina (SEA) (11 patients with multivessel disease (MVD) and 22 patients with singlevessel disease (SVD)) and 25 patients with chest pain syndrome (CPS). Sarpogrelate was administered to 22 of 33 patients with SEA in addition to aspirin therapy, and platelet aggregation, plasma serotonin concentration, and plasma plasminogen activator inhibitor (PAI) activity were measured before and 1 week after administration.Results and Conclusions
Serotonin level was higher in patients with MVD than in those with SVD (p < 0.05) and in those with CPS (p < 0.001). The formation of small-sized platelet aggregates was significantly higher in the high serotonin group than in the low serotonin group of SEA patients. The formation of large-sized platelet aggregates was significantly decreased by administration of sarpogrelate (P < 0.05). The formation of small- or medium-sized aggregates was not significantly decreased. Plasma PAI activity decreased significantly (P < 0.05) although the plasma serotonin concentration did not show significant change by administration of sarpogrelate. Plasma serotonin level is increased in relation to severity of coronary artery disease and plasma serotonin level is associated with increased platelet aggregation. Administration of sarpogrelate in addition to aspirin therapy reduces the increased platelet aggregation and PAI activity, and it may indicate that additional administration of sarpogrelate is useful for patients with SEA. 相似文献66.
Avian influenza A subtype H5N1 virus with its recombination potential with the human influenza viruses presents a threat of producing a pandemic. The consensus is that the occurrence of such a pandemic is only a matter of time. This is of great concern, since no effective vaccine is available or can be made before the occurrence of the event. We present arguments for the use of cell mediated immunity for the prevention of the infection as well as for the treatment of infected patients. Transfer factor (TF), an immunomodulator of low molecular weight capable of transferring antigen-specific cell mediated immune information to T-lymphocytes, has been used successfully over the past quarter of a century for treating viral, parasitic, and fungal infections, as well as immunodeficiencies, neoplasias, allergies and autoimmune diseases. Moreover, several observations suggest that it can be utilised for prevention, transferring immunity prior to infection. Because it is derived from lymphocytes of immune donors, it has the potential to answer the challenge of unknown or ill-defined pathogens. Indeed, it is possible to obtain an antigen-specific TF preparation to a new pathogen before its identification. Thus, a specific TF to a new influenza virus can be made swiftly and used for prevention as well as for the treatment of infected patients. 相似文献
67.
《Expert opinion on therapeutic targets》2013,17(1):75-89
Importance of the field: Tissue factor (TF) is the key initiator of the coagulation cascade. The exposure of subendothelial TF after vessel injury to blood is a critical step in hemostasis and in the pathogenesis of arterial and venous thrombotic disorders. Moreover, an additional role for TF overexpression and subsequent generation of TF:FVIIa complex, FXa and thrombin have been recently emerged, contributing in non-thrombotic manifestations such as inflammation, cancer growth and fibrosis. Areas covered in this review: The multivalent role of TF and the above mentioned proteases in disease is reviewed, with focus on their implication in non-thrombotic disorders, as suggested by clinical and experimental data. Moreover, potential therapeutic interventions using anticoagulation agents are discussed. What the reader will gain: A better understanding of the pathogenic role of the TF–thrombin pathway in the pathogenesis of disease and the effect of anticoagulants in the treatment of such disorders. Take home message: The TF-thrombin pathway, apart from the initiation of hemostasis and thrombosis, exert intracellular signaling activity through protease-activated receptors, participating in inflammation and tumor biology. Both low-molecular-weight heparins and recently developed anticoagulants rise as candidates for the modification of biological functions associated with disorders like sepsis, ischemia–reperfusion or cancer growth and metastasis. 相似文献
68.
目的:探讨抑郁症患者是否存在快感缺失以及快感缺失与奖励性动机损伤的相关性。方法对30例抑郁症患者(抑郁症组)和32名健康志愿者(对照组)采用贝克抑郁自评问卷、时间性快感体验量表及由电脑呈现的付出努力的奖励任务进行测评。结果抑郁症组贝克抑郁自评问卷总分显著高于对照组(P<0.01),时间性快感体验量表消费性及期待性快感缺失因子分及不同概率水平困难任务选择率均显著低于对照组(P<0.01);消费性和期待性快感缺失与高概率水平困难任务选择率呈显著相关( P<0.05或0.01)。结论抑郁症患者存在明显的快感缺失,且快感缺失与奖励性动机损伤呈显著相关。 相似文献
69.
70.
目的 比较TF、K3和EndoWave 3种机用镍钛锉预备S形树脂模拟根管的成形能力.方法 120个S形树脂模拟根管,随机分为3组,每组40例,使用TF、K3和EndoWave 3种器械分别进行根管预备,记录预备时间;数码显微镜获取预备前、后根管图像,使用Photoshop和ImageJ软件进行图像重叠,测量预备后根管冠方弯曲角度和根方弯曲角度的变化值;从根尖止点开始,每隔1 mm测量根管内、外侧壁树脂去除量,共10个测量点.以外弯量减去内弯量,表示中心定位能力.单因素方差分析进行统计学检验,显著性水平0.05.结果 TF预备时间为(14.00 ±4.56)s,显著短于K3和EndoWave[(59.53±35.92)s和(44.00±14.38)s] (P <0.05).3种器械预备后根管冠方和根方弯曲角度变化差异无统计学意义(P>0.05).3种器械预备后,根尖弯曲处,TF在内侧壁树脂去除量显著小于EndoWave和K3(P<0.05);冠部弯曲处,TF在外侧壁去除量显著小于K3(P<0.05);根管直线段,TF在内侧壁的去除量显著小于EndoWave和K3(P<0.05).中心定位能力方面,TF在距根尖孔L 5~ 9mm位点均显著优于EndoWave(P<0.05);除距根尖止点6mm位点以外,其他位点TF均与K3差异无统计学意义.结论 TF预备S形树脂模拟根管效率高,不良预备形较少且根管偏移较小. 相似文献