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71.
The effects of 17 alpha-oestradiol and 17 beta-oestradiol on basal and follicle-stimulating hormone (FSH)-stimulated inhibin B secretion by rat Sertoli cells were studied. Sertoli cells were isolated and cultivated from testes of 18-day-old Wistar rats in the presence and absence of FSH and different doses of oestrogens. On day 4 of culture, secreted inhibin was measured by enzyme-linked immunosorbent assay. Neither 17 alpha-oestradiol nor 17 beta-oestradiol had any effect on the secreted inhibin level in either the presence or absence of FSH. It is concluded that these oestradiols do not play an essential role in regulatory processes involving inhibin or FSH. 相似文献
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Schreiber M Ilamathi E Wolfson M Fender D Mueller S Baudoin M 《Nephrology news & issues》2000,14(12):44-46
Regardless of age or race, more patients preferred peritoneal dialysis (PD) than would be expected from the current ratio of patients treated with PD in the U.S. The percent of patients choosing PD seems to be largely influenced by the scope of information they receive prior to therapy initiation. In the absence of thorough treatment option education, a significant number of patients may be assigned a therapy when, in reality, they would have selected an alternative option. There is a need to further understand the correlation between a practice's PD utilization rate and the extent to which patients are given dialysis treatment options. 相似文献
74.
Schreiber S Kampf-Sherf O Gorfine M Kelly D Oppenheim Y Lerer B 《The Israel journal of psychiatry and related sciences》2000,37(4):302-307
We assessed whether the efficacy of plant-source derived phosphatydilserine (one of the phospholipids which play an important functional role in membrane-related processes in the brain) for treatment of age related cognitive decline is consistent with previous (placebo controlled) positive findings with bovine derivative of PS (BC-PS). Eighteen healthy elderly volunteers meeting Age Associated Memory Impairment inclusion and exclusion criteria were treated for 12 weeks with plant-source derived phosphatydilserine (PS) (100 mg x 3/day p.o.) and evaluated at base line, after 6 weeks of treatment and at the end of the trial. Fifteen concluded the study. All but two outcome measures elicited a significant drug over time effect. Post-hoc paired t-tests showed that the significant effect was attributable to an improvement from base line to week 6 and that effect was maintained at week 12. These results are encouraging. However, they await double-blind controlled verification in a large sample before suggesting that this may be a viable approach to the treatment of age-related cognitive decline, without exposing the patients to possible hazards involved in the treatment with bovine derivative of PS (BC-PS). 相似文献
75.
Hoffmann O Weih M Schreiber S Einhäupl KM Valdueza JM 《Cerebrovascular diseases (Basel, Switzerland)》2000,10(2):142-146
We present a new, non-invasive ultrasound method for the measurement of cerebral circulation time. After injection of a galactose-based echo-contrast agent (Levovist) into an antecubital vein, cerebral circulation time is measured as the interval between the beginning of a stable signal enhancement of at least 5 dB in the internal carotid artery and in the ipsilateral internal jugular vein. Both vessels are insonated simultaneously at the mandibular angle using a single 2-MHz range-gated transducer. For this study, 25 healthy volunteers ranging in age from 23 to 55 years (30.1 +/- 7.5 years; mean +/- SD) were examined. Cerebral circulation time was 5.6 +/- 1.7 s without significant side-to-side or sex-related differences. Measurement of circulation times offers a new possibility for the employment of echo-contrast agents in functional ultrasound. 相似文献
76.
Cerebrospinal anandamide levels are elevated in acute schizophrenia and are inversely correlated with psychotic symptoms. 总被引:7,自引:0,他引:7
Andrea Giuffrida F Markus Leweke Christoph W Gerth Daniela Schreiber Dagmar Koethe Johannes Faulhaber Joachim Klosterk?tter Daniele Piomelli 《Neuropsychopharmacology》2004,29(11):2108-2114
The endocannabinoids are a family of bioactive lipids that activate CB1 cannabinoid receptors in the brain and exert intense emotional and cognitive effects. Here, we have examined the role of endocannabinoid signaling in psychotic states by measuring levels of the endocannabinoid anandamide in cerebrospinal fluid (CSF) of acute paranoid-type schizophrenic patients. We found that CSF anandamide levels are eight-fold higher in antipsychotic-naive first-episode paranoid schizophrenics (n = 47) than healthy controls (n = 84), dementia patients (n = 13) or affective disorder patients (n = 22). Such an alteration is absent in schizophrenics treated with 'typical' antipsychotics (n = 37), which antagonize dopamine D2-like receptors, but not in those treated with 'atypical' antipsychotics (n = 34), which preferentially antagonize 5HT(2A) receptors. Furthermore, we found that, in nonmedicated acute schizophrenics, CSF anandamide is negatively correlated with psychotic symptoms (rS = -0.452, P = 0.001). The results suggest that anandamide elevation in acute paranoid schizophrenia may reflect a compensatory adaptation to the disease state. 相似文献
77.
Venous drainage patterns in a case of pseudotumor cerebri following unilateral radical neck dissection 总被引:2,自引:0,他引:2
Doepp F Schreiber SJ Benndorf G Radtke A Gallinat J Valdueza JM 《Acta oto-laryngologica》2003,123(8):994-997
We report the extracranial venous ultrasound findings in a case of pseudotumor cerebri (PTC) following unilateral radical neck dissection (rND). PTC is known to be a rare complication following bilateral rND, and is caused by venous outflow obstruction. Single cases of PTC have been reported after unilateral rND, and are thought to be due to resection of the dominant internal jugular vein (IJV) in the presence of a hypoplastic or aplastic contralateral transverse sinus. Our patient developed PTC despite prominent flow in the contralateral IJV as shown by venous ultrasound. No compensatory increase in flow in the vertebral veins was observed, as confirmed by digital subtraction angiography. We conclude that the physiological collateral function of the vertebral venous system and deep neck veins was insufficient and contributed to global venous outflow obstruction in our case of unilateral rND. 相似文献
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79.