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91.
Summary Cyclic adenosine 3,5monophosphate (cAMP) was assayed in CSF and plasma obtained from patients with multiple sclerosis. Decreased CSF cAMP levels were found in more than half of the patients while plasma cAMP was normal. The decrease is correlated significantly with the disability of the patient and with the progression of the disease. A low CSF cAMP level can be considered as prognostically unfavorable, particularly in the early stage of the disease. There was no correlation between the cAMP levels and the duration of the disease or with bouts and remissions. ACTH therapy did not normalize the decreased values. Obviously the decrease of CSF cAMP is related to the demyelination and not to the intensity of the pathological immunoreactions.
Zusammenfassung Es wurde das cyclische Adenosin-3,5monophosphat im Liquor von Patienten mit multipler Sklerose untersucht. Bei einem Teil der Patienten wurden auch die Vergleichswerte im Blutplasma bestimmt. Es zeigte sich bei mehr als der Hälfte der Patienten eine Verminderung der cAMP-Konzentration im Liquor bei normalem Plasmaspiegel. Diese cAMP-Verminderung erwies sich als signifikant abhängig von dem Schweregrad der Erkrankung bzw. der Erkrankungsprogredienz und ist besonders in frühen Erkrankungsfällen als prognostisch ungünstiges Zeichen anzusehen. Es fand sich kein Zusammenhang mit dem Krankheitsstadium, d.h. Schub bzw. Intervall, und mit der Erkrankungsdauer. Eine ACTH-Behandlung vermochte diese Verminderung der Werte nicht auszugleichen. Es wird die Wertigkeit dieser Befunde diskutiert.相似文献
92.
Summary Six patients with recently ruptured intracranial aneurysms were treated preoperatively with tranexamic acid (AMCA). Two patients received 6 g daily in i.v. infusion, two had 6 g daily by i.v. injection, and two patients were given AMCA 9 g daily by mouth during the first week after bleeding. Serial assays of AMCA and fibrin/fibrinogen degradation products (FDP) in cerebrospinal fluid (CSF) were performed during 6–13 days after the initial subarachnoid haemorrhage (SAH). Judged from the decline in CSF-FDP, an assumed therapeutic level of 1 mg/l of AMCA in CSF was reached within 24–36 hours after the first dose when the drug was administered intravenously and within 48 hours when the drug was given orally. 相似文献
93.
Iphigenia Phocas Themis Mantzavinos Dimitris Rizos Fotini Dimitriadou Katerina Arvaniti Pantelis A. Zourlas 《Journal of assisted reproduction and genetics》1992,9(3):233-237
Background Are follicles where no oocytes are retrieved empty follicles?Methods The levels of estradiol (E2), progesterone (P), testosterone (T), cortisol (F), and prolactin (PRL) of follicular fluids (FF) aspirated individually from 34 randomly selected IVF patients in whom no oocytes were recovered were compared with the respective hormone levels of FF obtained from the same patients when oocytes were retrieved. Two FF without oocytes of a 35th patient in whom no oocytes were retrieved were analyzed.Results Hormones did not differ significantly in the paired samples, while in the two FF of the 35th woman they were in agreement with cystic follicles.Conclusions It is necessary to differentiate aspirated follicles where no oocytes are retrieved from the empty follicle syndrome, which was not observed in the IVF series studied and should be rare in IVF patients. 相似文献
94.
绝育术后盆腔痛患者血浆、腹腔液中甾体激素与前列腺素相关性研究 总被引:5,自引:1,他引:4
本文测定绝育术后盆腔痛患者44例、输卵管绝育术后行输卵管复通术11例和正常妇女15例血浆与腹腔液中的甾体激素及前列腺素水平。结果发现:血中E_2与PGF_(2α)呈明显正相关,与TXB_2呈负相关,而P则与PGF_(2α)呈明显负相关;腹腔液中E_2与PGF_(2α)、TXB_2呈负相关。盆腔痛患者,包括异位症、无明显病变盆腔痛和盆腔静脉瘀血症3组的某种PG水平高于其他组。结果表明:血与腹腔液中PGs受甾体激素的影响,绝育术后慢性盆腔痛与PGs有关。 相似文献
95.
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
96.
Methods for the acquisition and analysis of intracranial pressure (ICP) signals are reviewed from clinical and technical perspectives. The clinical importance of ICP monitoring is presented, and methods for ICP transduction are briefly discussed. These methods include intraventricular catheters, subarachnoid screws, epidural techniques, and the new fiberoptic ICP measurement systems. Approaches to the visual analysis of the ICP waveform are presented, with special emphasis on the relationship between the ICP waveform and the arterial blood pressure signal. Methods of computer-based ICP analysis are also reviewed, including histogram and systems analysis methods. Methods to predict ICP pressure rises and to estimate intracranial compliance are also discussed. Finally, ICP monitoring is reviewed from the point of view of patient outcome. It is concluded that advanced ICP waveform analysis methods warrant further clinical evaluation to demonstrate their clinical usefulness. 相似文献
97.
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
98.
目的:探讨一种有效的外伤性脑脊液鼻漏修补方法。方法:分析本科收治的6例经颅修补的脑脊液鼻漏,采用带蒂骨膜瓣翻转缝合及EC胶严密封闭漏口。结果:无手术死亡,术后脑脊液漏均停止。通过4个月-2年随访,仅有1例术后3个月轻微复发,保守治疗自愈。结论:该方法取材方便,抗感染能力强,一次手术成功率高。尤其适应于额窦后壁、筛窦顶部骨折或缺损所致的脑脊液鼻漏。 相似文献
99.
Estimation of the amniotic fluid volume using the Cavalieri method on ultrasound images. 总被引:5,自引:0,他引:5
B Sahin T Alper A K?k?ü E Malatyalioglu R Kosif 《International journal of gynaecology and obstetrics》2003,82(1):25-30
OBJECTIVES: Presently, a design-based and practical method for measuring amniotic fluid volume (AFV) for routine clinical examinations has not been proposed. In this study we describe a new method, which combines the Cavalieri method with ultrasound imaging to estimate AFV. METHODS: We measured the AFVs of 14 women in the third trimester of pregnancy, and repeated our measurements three times for each woman. Parallel planimetric ultrasonographic images were obtained at every 2 cm along the longitudinal uterine axis. AFVs were calculated as the total of the multiples of the estimated cut surface areas by the section thickness. RESULTS: The mean estimated AFV was 380.5 cm3. The coefficient of error of each measurement was calculated and the mean was 0.108. The coefficient of correlation between the amniotic fluid index and our AFV estimations was 0.87. CONCLUSIONS: Design-based and efficient estimation of AFV is possible with the combination of consecutive ultrasound images and the Cavalieri method. 相似文献
100.
A computational fluid dynamics study of blood flow in the continuous flow ventricular assist device, Prototype No. 3 (CFVAD3), which consists of a 4 blade shrouded impeller fully supported in magnetic bearings, was performed. This study focused on the regions within the pump where return flow occurs to the pump inlet, and where potentially damaging shear stresses and flow stagnation might occur: the impeller blade passages and the narrow gap clearance regions between the impeller-rotor and pump housing. Two separate geometry models define the spacing between the pump housing and the impeller's hub and shroud, and a third geometry model defines the pump's impeller and curved blades. The flow fields in these regions were calculated for various operating conditions of the pump. Pump performance curves were calculated, which compare well with experimentally obtained data. For all pump operating conditions, the flow rates within the gap regions were predicted to be toward the inlet of the pump, thus recirculating a portion of the impeller flow. Two smaller gap clearance regions were numerically examined to reduce the recirculation and to improve pump efficiency. The computational and geometry models will be used in future studies of a smaller pump to determine increased pump efficiency and the risk of hemolysis due to shear stress, and to insure the washing of blood through the clearance regions to prevent thrombosis. 相似文献