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91.
ABSTRACT  The technique for gavage administration to rat nurslings was improved to allow determination of the direct effects of chemical substances in the nurslings. Rat neonates were treated with distilled water from postnatal day 1 through 20 using this technique. The viability of neonates during the administration period was comparable to that of untreated neonates. No adverse effects of this technique on the development of neonates were found, and no histological alterations of the esophagus or pharynx. Therefore, we conclude that use of our improved gavage administration method will contribute to ensuring successful neonatal development and thus allowing accurate assessment of the toxicological effects of test compounds on rat nurslings.  相似文献   
92.
目的研究不同给药方式对实体肿瘤抗癌药物疗效的影响,并通过动物实验验证。方法分别建立体内药代动力学和肿瘤内药物输运的集中参数模型,模拟单次快速注射和等时间间隔三次快速注射时肿瘤间质组织药物浓度Ct随时间的变化。实验小鼠分为两组,分别进行抗癌药羟基喜树碱(HCPT)单次快速注射和等时间间隔3次快速注射,观察其肿瘤内药物平均浓度。对数值模拟结果和动物实验结果进行比较。结果数值模拟结果显示,对于相同总量药物,等量等间隔的三次给药,肿瘤间质组织药物浓度Ct高于单次给药。动物实验的实测结果相同。结论3次给药的效果显著优于单次给药。集中参数模型基本能够定量反映不同给药方式的效果。  相似文献   
93.
The artemisinin derivative beta-artemether, an anti-malarial, was evaluated for its toxicity and tolerability in a 2-week, multiple-dose study in dogs. Eight beagle dogs (4 females, 4 males) were given beta-artemether by oral gavage 3 times daily at 45 mg/kg/dosing (a total daily dose-level of 135 mg/kg) for 2 weeks. This beta-artemether dose regime was well tolerated. Body weight changes were normal although feed consumption during the treatment period reduced compared to that of the pre-trial period. Clinical signs were transient spells of soft to liquid feces. On completion of the treatment period, the animals were sacrificed and submitted to a full macroscopic post-mortem examination. Designated organs were weighed and a complete light microscopic examination was performed on 43 selected tissues from 1 animal per sex, and on the liver, kidneys, thymus, mandibular lymph nodes and lungs of the three other animals per sex. Major findings were high liver weight and histopathologic findings of slight diffuse hepatocellular hypertrophy and distal tubular dilatation, together with flattened epithelium, in the kidneys. With the dose regime used in this trial beta-artemether produced no clinical or apparent histopathological signs of neurotoxicity in dogs.  相似文献   
94.
Objective and design: Since rebamipide is effective for the treatment of ulcerative colitis (UC), we examined the involvement of hepatocyte growth factor (HGF) in the action of rebamipide. Materials: Fifty-five and forty female Balb/c mice, respectively, were used in Exp. 1 and 2. Treatment: 50 mg/kg/day rebamipide (Exp. 1) and 1 × 107 pfu pAxCAHGF (the CAG promoter-driving HGF gene in adenovirus vector) (Exp. 2) were intrarectally introduced after induction of colitis by 4 % dextran sulfate sodium (DSS). Methods: Therapeutic effects were assessed by cell proliferation and apoptosis. Results: Rebamipide caused proliferation of epithelial cells at 10 days after treatment, and decreased apoptosis at 10, 14 and 21 days, compared with controls. Expression of HGF was greatly increased in rebamipide-treated mice. pAxCAHGF caused cell proliferation and apoptosis, which showed the same pattern as with rebamipide treatment. Conclusions: Rectal administration of rebamipide is effective for DSS-induced colitis in association with induction of HGF. Received 17 June 2006; returned for revision 23 August 2006; returned for final revision 29 October 2006; accepted by I. Ahnfelt-R?nne 14 December 2006  相似文献   
95.
Laboratory of Cellular Immunity and Laboratory of Bacteriology, Department of Laboratory Animals. Oncologic Scientific Center, Russian Academy of Medical Sciences, Moscow. (Presented by Academician of the Russian Academy of Medical Sciences N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 10, pp. 383–385, October, 1992.  相似文献   
96.
The recent emergence of severe acute respiratory syndrome (SARS) was caused by a novel coronavirus, SARS-CoV. It spread rapidly to many countries and developing a SARS vaccine is now urgently required. In order to study the immunogenicity of UV-inactivated purified SARS-CoV virion as a vaccine candidate, we subcutaneously immunized mice with UV-inactivated SARS-CoV with or without an adjuvant. We chose aluminum hydroxide gel (alum) as an adjuvant, because of its long safety history for human use. We observed that the UV-inactivated SARS-CoV virion elicited a high level of humoral immunity, resulting in the generation of long-term antibody secreting and memory B cells. With the addition of alum to the vaccine formula, serum IgG production was augmented and reached a level similar to that found in hyper-immunized mice, though it was still insufficient to elicit serum IgA antibodies. Notably, the SARS-CoV virion itself was able to induce long-term antibody production even without an adjuvant. Anti-SARS-CoV antibodies elicited in mice recognized both the spike and nucleocapsid proteins of the virus and were able to neutralize the virus. Furthermore, the UV-inactivated virion induced regional lymph node T-cell proliferation and significant levels of cytokine production (IL-2, IL-4, IL-5, IFN-gamma and TNF-alpha) upon restimulation with inactivated SARS-CoV virion in vitro. Thus, a whole killed virion could serve as a candidate antigen for a SARS vaccine to elicit both humoral and cellular immunity.  相似文献   
97.
Synthetic dyes were extracted from syrups, oral suspensions, tablets, gelatin capsules, suppositories and granules by ion-pair formation with tri-n-octylamine (TnOA) and back-extracted with perchlorate ions. Identification was performed by TLC on cellulose layers and by reversed phase ion-pair HPLC.  相似文献   
98.
99.
Summary Interferon is currently being evaluated for the treatment of disseminated cancer and viral diseases. Alpha interferons have shown to be effective in the treatment of a number of malignancies. Recombinant leukocyte A interferon (rIFN-A) is an alpha interferon produced by recombinant DNA techniques. A kinetic evaluation of rIFN-A following intravenous and intramuscular administration has not been adequately defined. The present study was designed to evaluate the kinetics of rIFN-A following intravenous and intramuscular administration of 3, 9 or 18×106 units to patients with disseminated cancer.A preliminary report of this study was presented at the meeting of the American Society for Clinical Pharmacology and Therapeutics in San Diego, March 1983 (1).  相似文献   
100.
Zusammenfassung Das Ziel der vorliegenden Untersuchungen bestand darin, das pharmakokinetische Profil von Adrenalin bei endobronchialer (e.b.) und intravenöser (i.v.) Applikation zu erarbeiten und die gemessenen Adrenalin-Plasmaspiegel mit hämodynamischen Messungen zu korrelieren. Die e.b. Applikation von 100 g/kg Adrenalin erwies sich als ebenso effektiv, wie die i.v.-Gabe von 10 g/kg. Dabei war der Wirkungseintritt der e.b.-Gabe von Adrenalin nur geringfügig um einige Sekunden verzögert. Die Bioverfügbarkeit für e.b. verabreichtes Adrenalin lag zwischen 80 und 85%. Der therapeutische Effekt blieb nach e.b.-Applikation von 100 g/kg Adrenalin wesentlich länger erhalten (ca. 30 min) als nach i.v.-Gabe von 10 g/kg (ca. 3–5 min). Aus den Ergebnissen wird geschlossen, daß die tiefe endobronchiale Instillation von 2–3 mg Adrenalin (verdünnt in 5–10 ml Kochsalzlösung) als alternative Dosierungstechnik bei klinischen Reanimationen betrachtet werden kann.
Pharmacokinetics and -dynamics of epinephrine administered endobronchially
Summary The present animal study was designed to investigate the pharmacokinetic behavior of epinephrine after endobronchial (e.b.) and intravenous (i.v.) administration and its correlation to pharmacodynamic measurements. We found the effectiveness of e.b.-epinephrine (100 g/kg BW) to be in the same magnitude as i.v.-epinephrine (100 g/kg BW) with only a slight delay in the pharmacodynamic onset of a few seconds. The bioavailability of e.b.-administration of epinephrine was in the range of 80–85%. The therapeutic effect of e.b.-epinephrine (100 pg/kg BW) lasted much longer (30 min) when compared to i.v.-epinephrine (10 g/kg BW) where the pharmacodynamic effect was terminated after 3 to 5 min. For the clinical situation of cardiopulmonary resuscitation a dose of 2–3 mg epinephrine in 5–10 ml of physiological saline instilled deeply into the bronchial system should be considered as alternative administration technique with fast onset and good effectiveness.
Herrn Prof. Dr. Dr. h.c. F. Stelzner zum 65. Geburtstag gewidmet  相似文献   
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