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71.
The inhibition of butyrylcholinesterase activity in human serum by protoberberine, benzophenanthridine and aporphine alkaloids as well as four model compounds has been studied. The mechanism of the inhibition is discussed on the basis of the different types of interaction of these compounds with butyrylcholinesterase and acetylcholinesterase. 相似文献
72.
The atypical neuroleptic, sulpiride is a selective D2 antagonist, having a preferential action on mesolimbic regions. The effects of acute and chronic treatment with sulpiride on aggressive behaviour in male mice were studied using an ethologically based analysis. It was hypothesized that sulpiride would diminish "threat" and "attack" but would not produce marked "immobility", because of the mesolimbic effect referred to above. Isolated albino male mice (experimental animals) were confronted by "standard opponents". Acutely-treated experimental animals received an intraperitoneal injection of sulpiride (20, 50 or 100 mg/kg) 30 min before testing. Chronically-treated animals received sulpiride (10, 20 or 50 mg/kg) once a day for 7 or 14 consecutive days. Acute treatment with sulpiride had an obvious antiaggressive effect, with significantly decreased time devoted to "attack" and "threat" behaviour. Although time spent in "immobility" was modestly increased, the time devoted to other motor behaviour was also increased. Chronic treatment for 1 or 2 weeks did not change any behavioural category, except "immobility". The antiaggressive action of acutely administered sulpiride is interpreted as a relatively specific dopaminergic antagonist effect and not as merely a non-specific correlate of its disruptive action on motor behaviour. The possible anxiolytic action of sulpiride is also discussed. 相似文献
73.
N-Deacetylcolchiceine (DAC) administered i.p. to rats decreased the level of serum cholesterol and apoB. It was accompanied by the fall of HDL-C due to the decrease of both HDL subfractions HDLa and HDLb, and by a rather weaker decrease of LDL-C. The levels of serum and lipoprotein triacylglycerols were not significantly affected. The "clearing reaction" to heparin in DAC rats differed from controls with regard to plasma cholesterol resulting in its accumulation in HDLa and LDL simultaneously with an increased activity of post-heparin lipoprotein lipase. These results suggest that the DAC accelerates the lipoprotein cholesterol metabolism. 相似文献
74.
Dedifferentiated clear cell chondrosarcoma 总被引:1,自引:0,他引:1
Kalil RK Inwards CY Unni KK Bertoni F Bacchini P Wenger DE Sim FH 《The American journal of surgical pathology》2000,24(8):1079-1086
75.
76.
77.
Stacy M Plum Arthur D Hanson Kirk M Volker Hong A Vu B Kim Lee Sim William E Fogler Anne H Fortier 《Clinical cancer research》2003,9(12):4619-4626
PURPOSE: Current combination treatment strategies in malignancy are designed to evaluate the use of cytotoxic drugs and antiangiogenic agents. Endostatin, a fragment of collagen XVIII, specifically inhibits proliferation, migration, and differentiation of endothelial cells in vitro as well as angiogenesis and tumor progression in in vivo models. In this study, we determine the antitumor effect of rhEndostatin administered alone or in combination with Adriamycin against established orthotopic murine mammary carcinoma. EXPERIMENTAL DESIGN: Mice bearing orthotopically established DA-3 mammary adenocarcinoma tumors received varying doses of rhEndostatin alone and in combination with Adriamycin to assess tumor growth inhibition. Additional studies of this in vivo combination included a determination of Adriamycin-induced cardiotoxicity and in vitro effects on human umbilical vein endothelial cell proliferation and cord formation. RESULTS: For single-agent activity, optimal tumor growth inhibition was observed after s.c. administration of 50 mg/kg/day rhEndostatin or 5 mg/kg Adriamycin injected i.v. every 4 days. Combination of Adriamycin with optimal or suboptimal doses of rhEndostatin resulted in synergistic inhibition of DA-3 tumor growth. Importantly, unlike other antiangiogenic agents, rhEndostatin did not exacerbate the cardiotoxicity of Adriamycin. The synergistic interaction between rhEndostatin and Adriamycin was also observed in vitro for inhibition of human umbilical vein endothelial cell proliferation and inhibition of cord formation. CONCLUSIONS: These data suggest that the synergy observed with rhEndostatin in combination with Adriamycin is exerted at the level of the endothelial cell and can result in enhanced tumor growth inhibition. The potential benefit of Adriamycin used in combination with rhEndostatin is being considered for clinical evaluation. 相似文献
78.
Fidel Cano Juan A. García-Velasco Antón Millet José Remohí Carlos Simón Antonio Pellicer 《Journal of assisted reproduction and genetics》1997,14(5):254-261
Purpose: Our purpose was to assess the endocrine status of women with polycystic ovaries (PCO) undergoing IVF, and to compare oocyte
quality with endocrine markers of the syndrome, in an attempt to define a subpopulation with poor quality oocytes.
Methods: This was a retrospective study. Patients were first endocrinologically analyzed: serum levels of androgens (T, androstenedione,
DHEAS), FSH, and LH as well as glucose and insulin after an oral glucose tolerance test (OGTT) were recorded and are expressed
as absolute values and area under the curve (AUC). Subsequently, they were followed over a 2-year period in which patients
underwent several attempts of IVF as well as serving as oocyte donors. Patients were divided into three groups: group I (n=4)
was women who displayed embryos unable to implant in 15 IVF cycles and 10 ovum donation cycles in which they served as donors;
group II (n=16) was PCO patients in whom IVF (n=38) and/or oocyte donation cycles (n=42) resulted in pregnancies; and group
III (n=13) was IVF patients with normal appearance of the ovaries by ultrasound. The endocrine status was compared with the
IVF results.
Results: There was no difference among groups in the endocrinological parameters tested, except for the OGTT which identified women
in group I as having higher serum glucose and insulin levels than patients in groups II and III. Similarly, the OGTT showed
higher serum glucose values in group II compared to group III. Women in group I were also obese. Patients in group III were
older than PCO patients and needed more gonadotropins to reach an ovarian response which resulted in a reduced number of oocytes
retrieved. Fertilization was also impaired in group I, in which no pregnancy was recorded.
Conclusions: This study shows that there is a particular subgroup of PCO patients with lower fertilization rates and embryos unable to
implant. These patients are obese and nonhyperandrogenic and show derangements of insulin secretion. 相似文献
79.
80.
FISH Preimplantation Diagnosis of Chromosome Aneuploidy in Recurrent Pregnancy Wastage 总被引:8,自引:0,他引:8
F. Vidal C. Giménez C. Rubio C. Simón A. Pellicer J. Santaló J. Egozcue 《Journal of assisted reproduction and genetics》1998,15(5):310-313
Purpose:
Our purpose was to detect aneuploidy for chromosomes 13, 16,18, 21, 22, X, and Y in preimplantation embryos from patients with a history of unexplained recurrent miscarriage.
Methods:
Three patients with a history of unexplained recurrent spontaneous abortion were included in this study. Embryos were biopsied at the eight-cell stage, individually fixed on slides, and processed for fluorescent in situ hybridization (FISH). A multiple FISH protocol for seven chromosomes pairs (13, 16, 18, 21, 22, X, and Y) has been developed.
Results:
A total of 39 embryos was studied with the multiple FISH protocol developed. Successful analysis of the biopsied embryos was achieved within the time limits usually allowed in a preimplantation diagnosis program. Analysis of the blastomeres showed that 17 embryos were chromosomally normal for the probes used, 16 embryos were aneuploid, and in 6 embryos no informative results were obtained.
Conclusions:
In the patients studied, a large proportion of embryos (41%) exhibited chromosomal abnormalities for the probes used. Preimplantation diagnosis to screen for chromosome abnormalities could be a feasible approach to improve the possibility of successful pregnancy in these couples. 相似文献