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21.
Male Sprague-Dawley rats and marmosets were given a single oral 25 mg/kg dose of [3-14C]coumarin and the excretion of radioactivity in the expired air, urine and faeces monitored up to 96 h. Excretion profiles were similar in both species with the bulk of the dose being excreted in the urine and faeces within 24 h. Chromatographic analysis of 0-48 h urine samples revealed similar metabolic profiles with only small amounts of unchanged coumarin and very little 7-hydroxycoumarin. Coumarin 7-hydroxylase activity was not detectable in hepatic microsomes from either species. These results demonstrate that the disposition of [3-14C]coumarin was similar in the rat and marmoset, a New World primate, and that both species, unlike man, are poor 7-hydroxylators of coumarin. 相似文献
22.
R S Walters H M Kantarjian M J Keating M Talpaz C C Childs K B McCredie E J Freireich 《Cancer》1987,60(8):1708-1712
Thirty patients with Philadelphia chromosome-positive lymphoid (20 patients) or undifferentiated (ten patients) chronic myelogenous leukemia in blast crisis were treated with 0.4 mg of vincristine by continuous intravenous infusion (CIV) daily for 4 days; (doxorubicin) 12 mg/m2 of Adriamycin (Adria Laboratories, Columbus, OH) by continuous intravenous infusion daily for 4 days; and 40 mg of decadron daily on days 1 through 4, 9 through 12, and 17 through 20 (VAD). Course 2 was given starting on day 24 with the addition of cyclophosphamide 1 g/22. Overall nine patients achieved complete remission (30%) and three attained a partial remission (10%), for an overall response rate of 40%. Four patients expired during induction whereas 14 had resistant disease. Response rate was significantly higher for patients with lymphoid compared to undifferentiated morphology (55% versus 10%; P = 0.05). In lymphoid blast crisis, Calla-positive disease was associated with a higher response rate compared to Calla-negative disease (75% versus 25%; P = 0.08). Eleven patients developed infections, and seven had fever without documented infections. The median overall survival was 29 weeks. Median survival was 43 weeks for patients achieving complete remission and 20 weeks for those with resistant disease. Remission duration was 39 weeks. After primary and salvage therapy, nine patients are alive, six of them in continuous remission for 19+ to 112+ weeks. The authors conclude that VAD chemotherapy is an effective regimen with acceptable toxicity in patients with lymphoid blast crisis especially those with Calla-positive disease. Alternate induction regimens for undifferentiated disease and for maintenance therapy are currently being investigated. 相似文献
23.
24.
L Walters P Bartel D K Sommers P Becker 《Methods and findings in experimental and clinical pharmacology》1988,10(7):419-425
This study investigated central anticholinergic drug effects on: (1) the Randt Memory Test, a relatively new instrument which measures the acquisition and recall of verbal and pictorial information; (2) the averaged photopalpebral reflex (PPR), an electrophysiological parameter, the validity of which needs to be further investigated in pharmacological research and; (3) mood as measured by a 16-item visual analogue scale. Atropine (1 mg and 2 mg), pirenzepine (20 mg) and a placebo were administered intramuscularly in a double-blind cross-over trial in eight healthy volunteers. There were no inter-treatment differences on the Randt Memory Test. This finding is seemingly in contrast to those reported by some authors using other memory tests. In contrast to the reported effects of some benzodiazepines, the anticholinergics used in the present study did not prolong the latencies of the PPR, but reduced the amplitudes. Visual analogue scales indicated central effects for both pirenzepine and atropine. This implies pirenzepine's penetration of the blood-brain barrier and a physiological function for central muscarinic-1-receptors. The significant anticholinergic effects were exclusive to the "alertness" factor. 相似文献
25.
The threshold for killing of freshly hatched Drosophila larvae exposed to continuous-wave (CW) ultrasound shows a minimum at approximately 0.3 MHz. This suggests that the stiffness of the material surrounding the gas bodies in the organism is comparable to water. From this, it is apparent that the gas bodies in three-day-old larvae that we have used in earlier studies are far larger than resonance size at the frequencies (1-5 MHz) used. Yet, these larvae were killed by short exposures to low-temporal-average-intensity pulsed ultrasound with peak intensities of the order of 10 W/cm2. Hence, it appears that "large" bubbles cannot be ignored in considerations of the biological effects of pulsed ultrasound and lithotripsy. 相似文献
26.
Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa 总被引:9,自引:7,他引:9
The objective was to test the hypothesis that the optimal cryoprotective
agent for cryopreservation of human spermatozoa would be a solute for which
cells have the highest plasma membrane permeability, resulting in the least
amount of volume excursion during its addition and removal. To test this
hypothesis, theoretical simulations were performed using membrane
permeability coefficients to predict optimal procedures for the addition
and removal of a cryoprotectant. Simulations were performed using data from
four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide,
(iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations
were applied to determine approaches for the addition and removal of 1 M
and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to
maintain a cell volume within their osmotic tolerance limits. Based on
these data, ethylene glycol was predicted to be optimal for minimizing
volume excursions among the solutes evaluated. These predictions were then
experimentally tested using glycerol as the control cryoprotectant and
ethylene glycol as the experimental cryoprotectant. The results indicate
that there was a higher (P < 0.05) recovery of motile spermatozoa after
cryopreservation when using 1 M ethylene glycol than with 1 M glycerol,
supporting the hypothesis that use of the cryoprotectant for which the cell
has the highest permeability will result in higher cell survival.
相似文献
27.
Haemoglobin H disease is described in successive generations of 2 Filipino families. The condition was asymptomatic. The inheritance pattern of haemoglobin H disease in these families appeared to be like that described for Thais. 相似文献
28.
Donor insemination: Dutch parents' opinions about confidentiality and donor anonymity and the emotional adjustment of their children 总被引:1,自引:4,他引:1
Brewaeys A; Golombok S; Naaktgeboren N; de Bruyn JK; van Hall EV 《Human reproduction (Oxford, England)》1997,12(7):1591-1597
Results from a comparative study investigating 38 donor insemination (DI)
Dutch families with 4-8 year old children are presented. The aims of this
study were to investigate parents' opinions on the issues of
confidentiality and donor anonymity, to assess the emotional development of
the children, and to examine in DI families the association between secrecy
with regard to the use of a donor and the emotional adjustment of the
children. The DI families were compared to families with a child conceived
by in-vitro fertilization (IVF) and to families with a naturally conceived
child. Secrecy appeared to be associated with DI and not with IVF: 74% of
the DI parents intended not to inform the child about the way in which
she/he was conceived, whereas none of the IVF parents intended to keep the
secret. Only one set of DI parents and two sets of IVF parents had actually
told the child. As to donor anonymity, a spread of opinions appeared among
DI parents; 57% preferred an anonymous donor, 31% would have liked non-
identifying information about the donor, 9% preferred the donor's identity
to be registered and 3% remained unsure. Parents' major concern was to know
more about the medical/genetic background of the donor. Mothers and fathers
in the DI families differed in their opinions concerning the issues of
confidentiality and donor anonymity: fathers, more often than mothers, were
secretive with regard to the use of a donor and husbands, more often than
their wives, were in favour of donor anonymity. With regard to the
emotional development of the children, more emotional/behavioural problems
were revealed among DI children than among children who were naturally
conceived. No association was found between secrecy and the
emotional/behavioural adjustment of the children.
相似文献
29.
30.
Kenneth S. Kendler Ellen E. Walters Kim R. Truett Andrew C. Heath Michael C. Neale Nicholas G. Martin Lindon J. Eaves 《Behavior genetics》1995,25(6):499-515
Self-report symptoms of anxiety are widely used in mental health and social science research as an index of current psychiatric
state. Previous twin studies have suggested that genetic factors account for a significant proportion of the variance in these
symptoms. To replicate and extend these findings, we examined self-report symtoms of panic-phobia and somatization in the
“Virginia 30,000” twin-family sample. Model fitting applied to 80 unique relationships in the twin-family pedigree produced
the following major results: (i) genetic effects were significant for both symptom factors, accounting for between 25 and
49% of the total variance, with the exception of symptoms of panic-phobia in females, where they accounted for 15–16% of the
variance; (ii) familial environmental effects were absent for symptoms of somatization, while for symptoms of panic-phobia
they accounted for a very small proportion of variance in males (≤1.2%) and a modest proportion in females (6–17%) (iii) spousal
correlations were present for both factors, ranging from +0.05 to +0.20; (iv) genetic factors which influenced symptoms were
generally the same in males and females, although their effect was greater in males; (v) heritability estimates were lower
in the population-based than in the volunteer sample; and (vi) when test-retest reliability was included in the model, results
suggest that genetic factors account for at least half of the stable variance for all symptom factors, except panic-phobia
in females. Our results support the validity of previous twin studies of self-report symptoms of anxiety and suggest that
genetic factors significantly influence these symptoms but familial-environmental factors play little or no etiologic role. 相似文献