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91.
As an ongoing effort to elucidate the mechanisms involved in the calcium-dependent fertility regulation process, the viscoelastic properties of the mucus obtained from lamb cervix and human semen, as well as their water and total protein contents after exposure to EDTA, a chelating agent, or Nonoxynol-9 (N-9), a spermicidal agent, were examined. The viscosity was measured using a Cone Plate Digital Viscometer, while the water and total protein contents were determined by the lyophilization process and the Lowry method, respectively. The significant changes in the rheological properties of mucus, such as its viscosity and the water content, upon exposure to EDTA were demonstrated. The viscosity of cervical mucus and human semen were significantly increased by EDTA treatment (as compared to the controls): lamb cervical mucus (2.9 ± 0.3 vs. 2.2 ± 0.3 cps) and human semen (5.0 ± 0.3 vs. 4.3 ± 0.3 cps), respectively. The hydration rate was decreased by EDTA treatment as compared with the control (93.6 ± 0.7 vs. 96.8 ± 0.8%). Among tested samples, the reduction in the percentage of sperm penetration through the cervical mucus was the highest in the mucus containing EDTA, which had the lowest water content (93.6 ± 0.7%), indicating that there is a positive relationship between the hydration rate of the cervical mucus and its ability to permit the penetration of spermatozoa. This result indicates that spermicidal activity exerted by high concentrations of EDTA is in part due to its effect on the rheological properties of cervical mucus or semen. 相似文献
92.
Dr. Franco Zunino Brunella Barbieri Ornella Bellini Anna Maria Casazza Cristina Geroni Fernando Giuliani Antonio Ciana Giorgio Manzini Franco Quadrifoglio 《Investigational new drugs》1986,4(1):17-23
Summary The chromophore-modified derivative of doxorubicin, 4-demethyl-6-0-methyl-doxorubicin, has been tested for antitumor activity in a range of experimental murine tumor systems. In contrast to the inactive 6-0-methyl derivative of daunorubicin, 4-demethyl-6-0-methyl-doxorubicin provided antitumor effects comparable to that of the parent compound. In addition, detailed DNA-interaction studies showed that the doxorubicin derivative retains the ability to bind DNA by the intercalation mechanism. However, the binding affinity was appreciably reduced following structural modification in the anthraquinone chromophore. On the basis of the proposed models of intercalation, these results could be rationalized in terms of steric influence of the bulky methoxy group. The results of this study are in agreement with the correlation already observed between DNA binding and relative antitumor activity of anthracyclines. 相似文献
93.
Martine Hascoët Michel Bourin Jacques Bradwejn 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):825-840
1. The mechanism of action of drugs might change according to the test used. Several noradrenergic drugs were tested in order to understand their implication in the mobility tests.
2. It was found that clonidine, an Alpha 2 agonist, acted differently according to the tast used. It provoked sedation in spontaneous activity test, and anti-immobility effects in the other tests.
3. Tall suspension test is able to show the double acting of clonidine.
4. Idazoxan might act either as an alpha 2 antagonist or as partial alpha 2 agonist. TST shown the unexpected partial alpha agonist effect of the molecule.
5. Forced swimming test is more specific for predicting antidepressant activity than tail suspension test which is close to a spontaneous activity model. 相似文献
94.
张永刚 《南通大学学报(哲学社会科学版)》2007,23(2):97-99
明中后期,王学盛极一时,程朱式微,以顾宪成、高攀龙为首的东林学人以东林书院为依托,起而纠王学空疏之流弊。究明儒学道脉,“提撕天下万世”,成为其讲经活动的主要目的,儒家经典成为其讲经活动的主要内容,体现了学术与政治相结合的道德救世理念。 相似文献
95.
以国内外发表的文献为材料,简述甘草酸在抗病毒方面研究进展。对甘草酸抗肝炎病毒、疱疹属病毒、HIV病毒及SAS病毒等机制进行了综述。甘草酸抗病毒活性强,能抑制多种不相关的DNA、RNA病毒的生长,并且不影响正常细胞的活性。但由于其脂溶性和生物利用度低,及长期使用会引起一些不良反应,而限制了它的应用。总的来说,甘草酸在抗病毒方面的前景良好,有其独特优势,但其抗病毒机制复杂,很多方面有待进一步研究。 相似文献
96.
目的探讨不同摄食控制方法对荷瘤小鼠生存期的影响。方法摄食控制组分别为每日限食2.0 g(DR)、隔1日断食限食4.0 g(IF)、隔2日断食限食6.0 g(SF)和隔1日断食不限食(IF1)4种方法,正常摄食为空白对照组(AL)。观察各组小鼠的体重变化和平均存活天数。结果DR组和IF组平均存活天数分别为19.52±5.24 d和17.96±4.49 d,比对照AL组15.75±1.83 d明显延长(P<0.001和P<0.01)。结论摄食控制恰当,可明显抑制肿瘤细胞的生长、延长荷瘤小鼠的生存期并提高生存质量。 相似文献
97.
The methanolic fraction of P. indica root extract was found to possess significant antiulcer activity in different experimental animal models. In preventive antiulcer tests, significant protective actions in acetylsalicylic acid, serotonin and indomethacin-induced gastric lesions were observed in experimental rats. The extract also afforded significant protection to chemically-induced duodenal lesion in guineapigs. Significant enhancement of healing process in acetic acid-induced chronic gastric lesions were also observed in the extract-treated animals. 相似文献
98.
Dr. S. Søresen H. J. Kirkeby H. Stødkilde-Jørgensen J. C. Djurhuus 《Neurourology and urodynamics》1986,5(1):5-16
The pressure variations at the maximal urethral closure pressure (MUCP) were continuously recorded in healthy female volunteers by means of a two-point microtip transducer catheter for one hour. Before the investigation a normal voiding was assured objectively and bladder instability was excluded. All women showed pressure variations both at the MUCP and more distally. The pressure variations, from 3 to 66 cm H2O, showed rhythmicity and three frequency ranges could be identified. Slow pressure waves with a frequency of one in eight to 19 minutes were observed. Relatively fast-pressure waves were observed (one every one to four minutes) and relatively fast-frequency pressure waves were observed (rate: one to eight per minute). The pressure variations of the urethra seem to be an aspect of normal urethral physiology possibly contributing to continence and urinary tract infection prevention. 相似文献
99.
Uta Lichter-Konecki Christian Benninger Werner E. Brandeis Peter Matthis Dieter Scheffner 《Pediatric hematology and oncology》1987,4(1):77-85
Thirteen children with acute lymphoblastic leukemia (ALL) were investigated before and during cytotoxic therapy. EEG findings were correlated with the clinical course and the therapy protocol and compared with normal data obtained from 295 healthy children. Frequency analysis of the background activity of the EEG revealed an initial slowing of the background activity prior to therapy and further slowing each time a combination of vincristine (VCR), daunorubicine (DAU) or adriblastine (ADR), prednisone (FRED), and L-asparaginase (L-ASP) was administered. The slowing of the background activity correlated only with the administration of these drugs. DAU, ADR, and FRED are not known to influence the EEG; therefore, VCR and L-ASP remain the primary candidates responsible for the central nervous system alteration. 相似文献
100.
G Tufveson W Geelings M Broyer F P Brunner H Brynger S R Dykes J H Ehrich W Fassbinder G Rizzoni N H Selwood 《Nephrology, dialysis, transplantation》1989,4(3):161-171
This paper summarises the information given on the 1986 EDTA Registry centre questionnaire which was returned by 82% of the 2,065 known dialysis and transplant centres in 33 European countries. Information is given on the number of patients alive on haemodialysis according to the type of dialysis facilities available where the patient was receiving dialysis and the number of patients receiving special types of dialysis. The centre questionnaire also included questions on testing for HIV infection, serological evidence or symptoms of AIDS and the diagnosis of hepatitis B in patients and staff. The data given in response to these questions are presented together with data on the involvement of dietitians and social workers in the treatment of patients with end stage renal failure. Finally, information on transplant activity in Europe and the treatment policies of transplanting centres is provided. 相似文献