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101.
A. Klausmair N. Singewald A. Philippu 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(2):155-160
Summary The effects of carotid occlusion on the release of catecholamines in the nucleus of the solitary tract (NTS) were investigated in anaesthetized cats. Two aspects of the nucleus (rostral or intermediate NTS) were superfused bilaterally through push-pull cannulae with artificial CSF and the release of the endogenous dopamine, noradrenaline and adrenaline was determined in the superfusate radioenzymatically. The superfusion rate was 150 l/min or 800 l/min. In some experiments, superfusion of the intermediate NTS was carried out after denervation of the aortic arch.In the rostral NTS superfused at a rate of 150 l/min, bilateral carotid occlusion led to a rise in blood pressure and decreased the release rate of dopamine. These changes continued after occlusion termination. The release rate of noradrenaline was transiently diminished during occlusion. The release of this amine was also decreased after occlusion termination. The release rate of adrenaline was not influenced during carotid occlusion, but it was found to be diminished after termination of the occlusion. Superfusion of the rostral NTS at a rate of 800 l/min also reduced the release rate of adrenaline after termination of carotid artery occlusion. In the intermediate NTS (superfusion rate 150 l/min) similar effects of the carotid occlusion on the release rates of dopamine and noradrenaline were observed. In this aspect of the NTS, denervation of the aortic arch abolished the decrease in the noradrenaline release during carotic occlusion, while the release rates of dopamine and adrenaline were decreased during and after termination of the carotid occlusion.The results suggest that (a) the rise in blood pressure in the carotid sinus after termination of a carotid occlusion decreases the release rates of noradrenaline and adrenaline in the NTS, (b) the decrease in the release of noradrenaline during carotid occlusion is due to impulses originating from the baroreceptors of the aortic arch.Thus, impulses from carotid sinus and aortic arch modify the release rates of noradrenaline in the NTS so as to counteract blood pressure changes.Supported by the Fonds zur Förderung der wissenschaftlichen Forschung
Send offprint requests to A. Philippu at the above address 相似文献
102.
P. Hartikainen H. Soininen K. J. Reinikainen J. Sirviö R. Soikkeli P. J. Riekkinen 《Journal of neural transmission (Vienna, Austria : 1996)》1991,84(1-2):103-117
Summary We have investigated neurotransmitter-related markers of the cerebrospinal fluid (CSF) in a carefully screened series of normally aging subjects in standardized conditions in order to find out the influence of age and other confounding factors on CSF measures. The levels of 3-methoxy-4-hydroxyglycol (MHPG) and the activity of acetylcholinesterase (AChE) also increased with age, while homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5 HIAA) and immunoreactivities of somatostatin (SLI), beta-endorphin (BLI) and adrenocorticotropic hormone (ACTH) were unrelated to age. The gender of subjects had no significant effect on the levels of neurotransmitter markers, while seasonal changes, as well as height and weight of the subjects seemed to cause some variations in the levels of HVA, dopamine--hydroxylase (DBH) and ACTH. The study underscores the importance of standardized conditions and matched patient groups in the CSF studies. 相似文献
103.
H R Withers H D Thames L J Peters 《International journal of radiation oncology, biology, physics》1982,8(12):2071-2076
The late effects of fractionated irradiation with neutrons have been relatively more severe than after x-irradiation. Reasons for the RBEn/x being higher for late than for acute effects may include: (1) Late effects are reduced more by fractionation of X ray doses than are acute effects, whereas, with neutrons, the fractionation response is the same in rapidly-and slowly-responding tissues; (2) Late-responding tissues are less "sensitized" (and are, therefore, relatively protected) by redistribution throughout the division cycle during a fractionated regimen than are acutely-responding tissues: since neutron responses are less affected by cell-cycle distribution than are X ray responses, the relative protection of slowly-responding tissues is less; (3) The target cells for late, but not acute injury, may repair potentially lethal damage after X ray, but not after neutron exposure. Thus, the dissociation of RBE values for acute and late injury reflects mainly the dissociation between acute and late responses to conventional fractionated X ray regimens and, from the point of view of complications of radiotherapy, we should not condemn neutrons but praise X rays. Since fractionation of neutron doses into increments equivalent to those used in X ray therapy does not provide a preferential sparing of slowly-responding tissues, it is reasonable to shorten the overall duration of neutron treatment to deliver the total dose tolerated by the relevant "late-effects" tissue(s) in the shortest time consistent with acceptable acute responses. 相似文献
104.
Differentiation of normal pressure hydrocephalus and cerebral atrophy by computed tomography and spinal infusion test 总被引:5,自引:0,他引:5
J. T. J. Tans 《Journal of neurology》1979,222(2):109-118
Summary The diagnostic value of computed tomography (CT) and spinal infusion test (SIT) was investigated in 27 patients with normal pressure hydrocephalus (NPH) and 35 patients with cerebral atrophy. The most consistent CT finding of NPH was dilatation of the temporal horns, that of cerebral atrophy widening of the convexity sulci. However, 43% of patients with cerebral atrophy demonstrated no cortical atrophy. The SIT showed an excellent relation with isotope cisternography and continuous intracranial pressure recording. NPH and cerebral atrophy were correctly differentiated in 71% by CT and SIT. A normal SIT and a CT scan without the typical features of NPH exclude impairment of cerebrospinal fluid absorption. An abnormal SIT and a CT scan showing ventricular enlargement without dilatation of convexity sulci, require isotope cisternography and possibly intracranial pressure recording to determine the degree of the absorption deficit.
Zusammenfassung Der diagnostische Wert von Computertomographie (CT) und Spinalen Infusions-Test (SIT) wurde bei 27 Patienten mit Normal Pressure Hydrocephalus (NPH) und 35 Patienten mit zerebraler Atrophie untersucht. Der häufigste CT-Befund des NPH war Erweiterung der Temporalhörner und bei zerebraler Atrophie eine Erweiterung der Konvexitätssulci. Aber 43% der Patienten mit zerebraler Atrophie zeigte keine Rindenatrophie. Der SIT zeigte eine sehr gute Korrelation mit Isotopenzisternographie und kontinuierlicher intrakraniellen Druckmessung. NPH und zerebrale Atrophie wurden korrekt differenziert in 71% mittels CT und SIT. Ein normaler SIT und ein CT-Scan ohne die typischen Merkmale von NPH schließen Liquorrückresorptionsstörungen aus. Ein abnormer SIT und ein CT-Scan, der einen Hydrozephalus ohne Erweiterung der Konvexitätssulci zeigt, erfordern eine Isotopenzisternographie und eventuell intrakranielle Druckmessung zur Ermittlung des Grades der Liquorrückresorptionsstörung.相似文献
105.
Bilateral traumatic caroticocavernous fistulae: total resolution following unilateral occlusion 总被引:1,自引:1,他引:0
Balloon occlusion is the accepted treatment for direct post-traumatic caroticocavernous fistula. We present a case of bilateral
traumatic fistulae associated with a pseudoaneurysm. Resolution of both fistulae occurred following treatment of one of them
by balloon occlusion of the internal carotid artery. This case highlights the importance of considering a more conservative
approach to bilateral fistulae or those associated with a pseudoaneurysm. We review other treatment options.
Received: 1 October 1999/Accepted: 20 October 1999 相似文献
106.
甘西鼠尾草注射液和丹参注射液抗大鼠急性脑缺血和抗脂质过氧化作用的比较 总被引:6,自引:2,他引:6
目的:比较甘西鼠尾草和丹参两种注射液对大鼠急性脑缺血的影响,并对其作用机理进行探讨。方法:采用大脑中动脉阻断术(MCAO)制作大鼠急性脑缺血模型。采用计算机图像分析仪测定脑梗死的体积,TBA比色法测定血清MDA含量,放免法测定血清SOD含量;电子自旋共振(ESR)法测定药物对羟自由基的清除作用。结果:甘西鼠尾草注射液和丹参注射液均可明显减小急性脑缺血大鼠脑梗死体积,降低血清MDA含量,升高血清SOD含量,体外清除羟自由基的作用甘西鼠尾草强于丹参。结论:甘西鼠尾草和丹参两种注射液作用基本相同。提示甘西鼠尾草有可能成为丹参的代用品。 相似文献
107.
108.
D.E. Miga L.F. McKellar S. Denslow H.B. Wiles C.L. Case P.C. Gillette 《Pediatric cardiology》1997,18(3):204-207
Catheter ablation in children requires placement of multiple large femoral venous sheaths and catheters. Magnetic resonance
angiography (MRA) was used to evaluate the effect of indwelling lines on femoral venous blood flow. Between October 1993 and
February 1994 a total of 17 patients scheduled for catheter ablation underwent venous MRA. Two-dimensional time-of-flight
MRA was performed 12–70 hours after catheterization on all patients. All patients received intravenous heparin during the
procedure and had aspirin therapy instituted after ablation. Eighteen catheter ablations and MRA studies were performed on
the 17 patients (one patient underwent repeat ablation). There were 7 females and 10 males, with a mean age of 14.8 ± 4.2
years (range 8–21 years). Patients had three venous sheaths inserted in the left femoral vein (5F, 6F, and 7F with external
diameters measuring 1.7, 2.0, and 2.3 mm, respectively) and one sheath in the right femoral vein (7F). Four patients (22%)
had altered venous flow (two complete obstructions and two partial obstructions) following catheterization. None of these
patients experienced symptoms or complications. It was concluded that there is an increased incidence (22%) of venous obstruction
following catheter ablation, but there are no related complications. Venous MRA provides a rapid, noninvasive method for evaluating
venous flow abnormalities and possibly detects patients at risk for complications. 相似文献
109.
Transcatheter Closure of Atrial Septal Defects by the “Buttoned” Device: Complications and Need for Surgical Revision 总被引:2,自引:0,他引:2
H. P. Gildein S. Däbritz A. Geibel K. Sarai J. Vazquez–Jimenez W. Hügel R. Mocellin 《Pediatric cardiology》1997,18(5):328-331
Immediate and medium-term experience with transcatheter closure of a secundum atrial septal defect by the ``buttoned' device
in seven patients is reported. Complications occurred in two patients during the procedure. In one patient with complications,
the occluder was partly released in the right atrium. All efforts to correct its position were unsuccessful and caused considerable
deformation of the device, which had to be removed surgically. In the other patient with complications, disconnection of the
occluder and counteroccluder occurred immediately after removal of the loading wire. Both parts were retrieved by catheter.
Five patients had uneventful closure of the atrial septal defect. On follow-up, however, displacement of the device towards
the mitral valve was observed in two patients, which caused mitral regurgitation. Surgical removal of the device and repair
of the mitral valve was necessary in both patients. Two years after the procedure, the atrial septal defect was closed completely
in two of the remaining three patients and a small residual defect persisted in one patient. 相似文献
110.
Mark X. Ransom Alfredo J. Garcia Kerry Doherty Robert Shelden Ekkehard Kemmann 《Journal of assisted reproduction and genetics》1997,14(1):35-38
Purpose: Our aim was to examine the potential of the uterine cavity to affect fertilization and early embryo development.
Design: A prospective IRB-approved protocol for patients fulfilling study eligibility criteria was used.
Methods: Patients studied included those with primary or secondary infertility, aged less than 38 years, with no history of severe
male-factor infertility, and with hysterosalpingogram-and laparoscopic-confirmed bilateral proximal tubal occlusion. Superovulation
induction was accomplished with a combination of GnRH agonist and menotropins, with serum hormonal and sonographic monitoring.
Within 24 hr prior to, and again at the time of, ovulatory hCG administration, progesterone (P4) was given. Sonographic-guided
transvaginal retrieval was performed 35 hr after hCG. Between four and six oocytes were returned to the uterine cavity, admixed
with sperm, immediately following retrieval. Luteal support consisted of daily P4 administration.
Results: Of the 20 patients recruited for the study, all completed the retrieval and transfer procedure. A total of four clinical
pregnancies was achieved, with one early first-trimester loss, one late first-trimester loss (Trisomy 14), and two healthy
term infants delivered. IVF of surplus oocytes demonstrated a 82.5% fertilization rate and 66.7% cleavage following cryopreservation.
Conclusions: Human fertilization can be achieved through direct uterine transfer of gametes. Furthermore, administration of P4 prior to
the ovulatory dose of hCG is compatible with in vitro or in vivo fertilization and implantation. 相似文献