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71.
72.
研究了聚环氧氯丙烷(PECHCH)/N(4-乙氧基苄叉)4-丁基苯胺(EBBA)复合膜对氧气和氮气的透过性和选择性。用示差扫描量热计(DSC)、解偏振光强仪(DLI和偏光显微镜考察了复合膜的形态结构。结果表明,当PECH/EBBA复合膜处于液晶的向列相转变温度时,有较高的气体透过性和选择性。发现只有复合膜中EBBA含量在30wt%以上,PECH和EBBA呈非均相混合时,才有较明显的富氧效果。当EBBA含量达50wt%时,氧氮分离系数α=3.78。 相似文献
73.
通过8名健康志愿者服药后的对照实验,用微生物法检测血药浓度,按一室模型配置求算药物动力学参数,探讨西咪替丁对林可霉素体内过程的影响。结果表明,西咪替丁不能改变林可霉素的吸收速率(Ka)和消除速率(Ke),但可通过增加其吸收程度或改变其分布容积,使林可霉素的血药浓度和生物利用度分别增加约19%和27%。 相似文献
74.
Many epidemiological studies have shown the magnitude and seriousness of mental disorders in developing countries. However, mental health care remains unsatisfactory owing to lack of skilled manpower and many other social and medical priorities. General practitioners and other health personnel can significantly help in extending mental health care provided they receive adequate training during their medical curriculum. With this aim, the Department of Psychiatry at Addis Ababa University runs a 6-week full-time course for undergraduate medical students. Its chief objectives, teaching methods, achievements and shortcomings are discussed in the paper. 相似文献
75.
A rapid nonsterile short-term assay has been investigated in which percent inhibition of incorporation of the DNA precursor (3H)-thymidine is measured following exposure of tumor cells to the test drugs. To evaluate the usefulness of the short-term assay in providing a rapid reliable assessment of chemotherapeutic response, the short-term assay was compared with the soft agar clonogenic assay. Sensitivity to five anticancer drugs was compared using three human tumor cell lines (epidermoid carcinoma of the oral cavity, pancreatic carcinoma, and bladder carcinoma). The short-term assay produced results that were similar to results of the clonogenic assay in two of the three tumors tested, for three drugs (cis-platin, doxorubicin, and BCNU), but did not detect responses to two antimetabolites (5-FU and MTX) in any tumor. Further studies of this short-term assay should focus on alkylating agents and other nonantimetabolites. 相似文献
76.
Correlation between 5-HT7 receptor affinity and protection against sound-induced seizures in DBA/2J mice 总被引:2,自引:0,他引:2
Anne Bourson Véronique Kapps Catherine Zwingelstein Alain Rudler Frank G. Boess A. J. Sleight 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(6):820-826
Audiogenic seizures can be induced in DBA/2J mice following intense auditory stimulation. A number of neurotransmitters, including
5-hydroxytryptamine (5-HT), are believed to be involved in mediating this effect since it has been shown previously that depletion
of 5-HT or blockade of 5-HT receptors protects DBA/2J mice from these audiogenic seizures. The present study was undertaken
to determine whether antagonism of the newly identified 5-HT7 receptor may protect DBA/2J mice from audiogenic seizures by attempting to correlate in vivo potency of compounds with their
affinity at the 5-HT7 receptor. All compounds used in the correlation were shown to be antagonists at the 5-HT7 receptor and a statistically significant correlation was observed between 5-HT7 affinity and doses for half-maximal response (ED50) for protection of DBA/2J mice from sound-induced seizures (r = 0.80; P < 0.05). No significant correlation was observed between in vivo activity and affinity at either 5-HT1A, 5-HT2A or 5-HT2C receptors. It is also unlikely that interactions between the 5-ht5 receptor will protect DBA/2J mice from audiogenic seizures since metergoline and mesulergine which are both active in this
in vivo model have no affinity for the 5-ht5 receptor. There are similarities between the pharmacology of the 5-HT7 receptor and that of the 5-HT1A receptor, however the correlation between the in vivo potency in DBA/2J mice and 5-HT1A affinity was not significant. Furthermore, the 5-HT1A receptor antagonist WAY 100135 did not protect DBA/2J mice from audiogenic seizures at doses that antagonise 5-HT1A receptor-mediated effects in mice. These data suggest that antagonism of 5-HT7 receptors may protect against audiogenic seizures in DBA/2J mice although a definitive conclusion must await studies with
selective 5-HT7 antagonists.
Received: 20 March 1997 / Accepted: 10 August 1997 相似文献
77.
特异性荧光偏振免疫法监测521例肾移植后环孢素A全血浓度3275次 总被引:2,自引:0,他引:2
目的通过监测肾移植后病人环孢素A(CsA)全血浓度 ,提出CsA在三联免疫抑制用药方案中的理想治疗窗。方法用特异性荧光偏振免疫法测定CsA全血浓度 ,对521例病人监测3275次 ,按术后时间及临床表现分组比较。结果肾移植后<1 ,、1~3、3~6、6~12个月、1~2和>2年的CsA全血谷浓度的理想治疗窗应分别为250~450、200~400、150~300、100~250、100~200和100~180μg/L。结论CsA全血浓度在上述范围内 ,中毒反应和排异反应明显减少 相似文献
78.
Frank G. Holz Caren Bellmann Heimo Steffen Bernhard Nölle Jens Huober Hermann Krastel Evangelos Alexandridis 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1997,94(5):337-342
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang
am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart
eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri.
Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben.
Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina.
Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische
St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente,
der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden.
Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein.
Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression
identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in
Betracht.
相似文献
79.
Chretien Marie Francoise; Lebouvier Brigitte; Denis Alain; Chappard Daniel 《Human reproduction (Oxford, England)》1998,13(10):2767-2771
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments. 相似文献
80.
The present study was designed to examine the effects of a >30kDa fraction of medium conditioned for 2 days by adult rat seminiferoustubules on inhibin secretion by cultured tubules, and on spermatogenesisand fertility of male rats. Inhibin secretion was assayed byadding the >30 kDa fraction to 5 cm segments of adult ratseminiferous tubules and measuring inhibin by radioimmunoassayat 2 day intervals. Fertility was assayed by injecting malerats daily for up to 45 days with the >30 kDa fraction andthen mating them with a proestrus female, or by injecting for15 days and mating them with two female rats. The assay usedto evaluate the in-vivo effect of the >30 kDa fraction onthe testis involved an assessment of frequencies of seminiferoustubule stages scored by transillumination on intact tubules.The addition of the >30 kDa fraction to the adult rat seminiferoustubules cultured for 2 days resulted in an inhibition of inhibinsecretion into the medium. This effect was reversed when thefraction was removed and changed with fresh medium and culturedfor a further 4 days. The >30 kDa fraction administered i.p.to adult male rats resulted in a low fertilization rate comparedto control rats (67%) (P < 0.05). The assessment of frequenciesof seminiferous tubule stages scored by transillumination showedan increased frequency of stage VI and decreased frequency ofstages VII and VIII after treatment. The results of the presentstudy provide additional evidence that local regulation of Sertolicell function is mediated by a >30 kDa component or componentssecreted by adult seminiferous tubules which could arrest spermatogenesis. 相似文献