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1.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究   总被引:5,自引:0,他引:5  
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。  相似文献   
2.
Juvenile-onset acid maltase deficiency with unusual familial features   总被引:2,自引:0,他引:2  
From early childhood, two brothers had mild gait difficulties due to acid maltase deficiency (AMD). Biochemical studies of family members were consistent with autosomal recessive inheritance, but the asymptomatic mother had AM activity in the homozygote range, and her parents had decreased AM activity. The asymptomatic mother may be homozygous for the adult-onset variant of AMD. Alternatively, either the mother or the children may be genetic compounds of the childhood and adult forms of AMD.  相似文献   
3.
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
4.
Imipenem was evaluated for its activity against Staphylococcus epidermidis in vitro and in a rabbit model of endocarditis. The MBC for imipenem of 55 methicillin-resistant S. epidermidis isolates from patients with prosthetic valve endocarditis increased by eightfold or greater with increasing inoculum size; there was no inoculum-associated increase in the imipenem MBC for 20 methicillin-susceptible S. epidermidis isolates. Endocarditis was produced in rabbits with either a methicillin-susceptible or a methicillin-resistant S. epidermidis isolate to investigate the correlation in vivo of the in vitro inoculum effect for imipenem. Six days of imipenem treatment eradicated methicillin-susceptible S. epidermidis from vegetations of infected rabbits significantly better than no therapy but was less effective against methicillin-resistant S. epidermidis in this regard. Among methicillin-resistant S. epidermidis-infected rabbits, 6 days of imipenem therapy (i) was not significantly better than that of the control and was significantly worse than that of vancomycin in eradicating bacteria from infected vegetations and (ii) increased the frequency of imipenem-resistant subpopulations in infected vegetations. Resistant subpopulations were not seen in vegetations from untreated or imipenem-treated, methicillin-susceptible S. epidermidis-infected rabbits. Imipenem may not be effective therapy for serious human methicillin-resistant S. epidermidis infections.  相似文献   
5.
The present study investigated the perception of sweetness of aspartame in comparison to various concentrations of sucrose. Twenty-seven subjects were randomly assigned to taste a chilled or room temperature Kool-Aid beverage sweetened with either aspartame or five different concentrations of sucrose. Subjects assessed the perceived similarity in sweetness of an aspartame-aspartame pair and five different aspartame-sucrose pairings and rated each beverage on five bipolar adjectives. Analysis of the similarity ratings revealed that subjects did not perceive the pairs of beverages to differ in perceived sweetness. Analysis of the adjective ratings revealed that aspartame and the lower sucrose concentrations were perceived as being less sweet and more sour than the higher sucrose concentrations.  相似文献   
6.
After reduction of a disulfide bond at or near the mu opioid binding site in rat brain membranes, incubating membranes with 14 beta-bromoacetamido derivatives of either morphine, dihydromorphine, morphinone, or dihydromorphinone resulted in the irreversible inhibition of mu opioid binding to rat brain membranes. Without the addition of the disulfide bond-reducing reagent dithiothreitol, these affinity ligands bound reversibly to opioid binding sites. Binding to either delta or kappa opioid binding sites was not altered by alkylation of the membranes with the affinity ligands. The percentage of irreversible inhibition of mu opioid binding was dependent on the time and temperature of the incubation of membranes with the affinity ligands and on the concentrations of dithiothreitol and the affinity ligands. Incubating membranes with morphine afforded almost complete protection from alkylation of the mu opioid binding site. Naloxone and the l-isomer levorphanol also protected the site from alkylation, whereas the d-isomer dextrorphan and the kappa-selective opioid U50,488H did not protect the site. The mu-selective peptide [D-Ala2, (Me)Phe4,Gly(ol)5]enkephalin was the peptide that afforded the greatest protection. These studies have shown that, after the reduction of a disulfide bond at or near the mu opioid binding site, this sulfhydryl group can be specifically alkylated, resulting in the affinity labeling of the mu opioid binding site.  相似文献   
7.
The objective of this investigation was to study the effects of lidocaine upon postnatal development of the rat. Lidocaine, 6 mg/kg (21 mumol/kg), was given to a group of 12 rats. Injections were administered intramuscularly, bilaterally in the masseter muscles, once a day on days 10 and 11 of pregnancy. Twelve control rats were given physiologic saline. Clinical signs, mortality, body weight, and food consumption were recorded during pregnancy and lactation. The duration of gestation was also recorded. The development of the offspring was monitored by tests of spontaneous activity, nociception, learning ability, and physical development. No clinical signs of adverse reactions were seen in any of the groups. In the majority of the learning ability tests, the control and lidocaine-treated groups showed similar results. However, in the schedule of differential reinforcement of low rates of responding (DRL 20), the lidocaine-exposed males received more reinforcements than the controls and made fewer responses. In the tests of nociception, a significant difference between sexes was recorded, in that the females were more sensitive than the males in the shock-titration test. Physical development, as monitored by swimming ability and spontaneous activity, showed no inter-group difference. The present results indicate that prenatal exposure to lidocaine fails to result in postnatal impairment of the development of behavioral performance of a wide range of tasks.  相似文献   
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BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  相似文献   
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