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261.
G. Cannella M. D. Galva M. Campanini A. M. Cesura S. De Marinis G. B. Picotti 《European journal of clinical pharmacology》1983,25(3):299-302
Summary To evaluate the role of adrenergic mechanisms in the acute response of renin to furosemide, plasma renin activity (PRA) and plasma catecholamine concentrations were measured for 3 h after i.v. administration of furosemide 1 mg/kg to 8 patients with mild essential hypertension. Furosemide induced a prompt and long-lasting increase in renin, with PRA more than doubled at all times. The increase in PRA within the first 30 min paralleled the peak increases in urinary water and sodium flow rates, and significant decreases in plasma volume and central venous pressure. There was no change in plasma catecholamine concentrations. Plasma noradrenaline was increased significantly at 60 min and adrenaline at 90 min, once furosemide had induced a marked loss of body-fluid and 65% decrease in central venous pressure. Both catecholamines remained elevated until the end of the study, whereas urinary water and sodium flow rates had returned to their pre-treatment values by 150 min. Mean blood pressure was essentially unchanged throughout the study, whereas heart rate increased significantly after 90 min. The findings suggest that in mildly hypertensive patients adrenergic mechanisms are not involved in the initial renin response to furosemide, but they come into play later, probably as a result of reflex sympathetic activation triggered by marked volume depletion. 相似文献
262.
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
263.
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
264.
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
265.
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
266.
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
267.
丹参关节内注射对兔膝骨关节炎细胞因子IL-1及TNF的影响 总被引:24,自引:3,他引:24
为了解丹参注射液膝关节内注射对兔膝骨性关节炎中白细胞介素(IL-1)和肿瘤坏死因子(TNF)水平的影响,探讨其治疗骨性关节炎的机理,将64只兔随机分为4组,采用兔膝关节腔内注入木瓜蛋白酶造成骨关节炎的病理模型,以丹参与激素分别行关节腔内注射治疗进行对比观察,于造模后2、4、6、8周分别取材,采用双抗体夹心酶联免疫吸附实验(ELISA)法,分别测定各组、各期兔膝关节液中IL-1及TNF水平。结果显示,造模组IL-1及TNF的水平明显高于丹参组及激素组,有显著差异;空白组未能测出IL-1及TNF;激素组低于丹参组,有统计学差异。表明IL-1及TNF在骨性关节炎发病过程中可能起重要作用,丹参能有效降低骨性关节炎中IL-1及TNF的水平,其效果低于激素组,表明丹参关节内注射能有效治疗骨性关节炎,但效果略次于激素。 相似文献
268.
丹参液在体外对血小板活化的抑制作用研究 总被引:8,自引:1,他引:8
目的:探讨丹参液在体外对血小板活化的抑制作用。方法:用流式细胞仪三色分析测定丹参液在体外对血小板活化膜表面纤维蛋白原受体(FIB-R)和P-选择素(CD42P)的表达。结果:丹参液有保护血小板FIB-R和CD42P被活化,同时部份抑制ADP活化血小板。结论:丹参液是一种较强的抗血小板活化药物,在血栓性疾病的防治中有积极作用。 相似文献
269.
270.
目的 探讨经迷路进路听神经瘤切除术后脑脊液漏发生的影响因素及处理方法。方法1999年以来采用迷路进路或扩大迷路进路听神经瘤切除术 85例 ,前 4 1例采用传统关闭术腔技术 ,后4 4例对关闭技术进行改良 ,分析其脑脊液漏的发生率。发生脑脊液漏者行保守或手术治疗。结果传统关闭技术组中脑脊液漏的发生率为 19 5 % ( 8 4 1) ,改良关闭技术组中脑脊液漏的发生率为 2 3%( 1 4 4 ) ,两组差异有显著性意义 (P =0 0 13)。传统关闭技术组中脑脊液漏多数发生在大型听神经瘤中 ,其发生率随肿瘤增大有上升的趋势。 9例脑脊液漏的患者中 ,3例经保守治疗 ;6例经手术修补成功 ,其中 5例 1次修补成功。结论 改良关闭术腔技术可显著降低经迷路进路听神经瘤切除术后脑脊液漏的发生率 ,手术修补为终止脑脊液漏的有效措施 相似文献