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11.
The MIC values of the antifungal drug ketoconazole were evaluated on 66 Candida albicans strains. These strains were isolated from 26 HIV-1 infected patients with oral recurrent candidosis. Each episode of oral candidosis observed in these patients was orally treated with ketoconazole (200 mg/day) until the clinical disappearance of the lesions. The most frequent MIC values were 20 micrograms/ml and 10 micrograms/ml, observed in 37 and 19 isolates respectively. Only strains from five patients showed changes in their susceptibility to ketoconazole. This fact could indicate that a different strain causes the subsequent reappearance of the oral lesions, rather than the drug selecting resistant fungal strains. Our results stress the role of host characteristics in the occurrence of candidal infections, pointing to the progressing failure of the immunological response as the most important factor responsible for the recurrence of oral candidosis during HIV-1 infection.  相似文献   
12.
本文采用层析法进行鉴定,用氨基酸分析仪测氨基酸的含量,为胎盘组织液的质量标准提供可靠依据。本法准确率为99%。  相似文献   
13.
In the Cardiff acuity test, simple pictures on an otherwise neutral grey card are defined by borders consisting of a relatively broad white band flanked by black bands each half the width of the white band. Higher levels of acuity correspond to the ability to detect figures defined by narrower borders, the figure size remaining constant. It is sometimes implied that the acuity limit corresponding to each card can be equated with different levels of grating resolution, the total width of the border corresponding to the overall grating period. It is shown that although the spatial frequency spectra of the Cardiff figures, like those of other vanishing optotypes, lack very low-frequency components, they have a complex two-dimensional form. The figures have wide spatial bandwidth and no well-defined discrete frequency components. As a result, the relationship between measured Cardiff and grating acuity will vary somewhat, depending upon the particular optical, neural or other deficits of the individual being tested.  相似文献   
14.
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   

15.
16.
OBJECTIVE: In the present study, we evaluated the anti-inflammatory activity of Poria cocos (PoCo) on experimentally induced irritant contact dermatitis (ICD) in a repeated sodium lauryl sulphate (SLS) irritation model. METHODS: The anti-irritative effect of PoCo was evaluated with a visual score and quantified by non-invasive bioengineering methods, namely chromametry and transepidermal water loss. Three concentrations of PoCo in base cream DAC (amphiphilic emollient; German pharmacopoeia) were tested in a 4-day repetitive irritation test using SLS. RESULTS: A statistically significant anti-inflammatory activity was observed for PoCo by all three methods when applied in parallel to the induction period of ICD. Application of PoCo after induction of ICD once a day for 5 days, starting just at the end of 4 days, was without any effect. CONCLUSION: An anti-inflammatory efficacy of PoCo on the elicitation phase of the ICD induced by repeated SLS test could be observed and quantified by three independent, non-invasive biophysical assessment parameters. This effect can be explained by its influence on pro-inflammatory enzymes, namely phospholipase A2.  相似文献   
17.
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination.  相似文献   
18.
测定了马杜霉素渣中铅、砷、镉、铬的含量及对小白鼠的毒性和对鸡的抗球虫性能。试验结果:马杜霉素渣中铅含量1.05mg/kg,砷含量小于1.0mg/kg,镉含量1.2mg/kg,铬含量26mg/kg;马杜霉素渣对小白鼠的LD50为354.65mg/kg,比马杜霉素毒性大。马杜霉素渣的抗球虫指数为173~175.1,属中等强度抗球虫药。以上结果表明,马杜霉素渣可以作为抗球虫药应用,但应用时要防止中毒的发生。  相似文献   
19.
An improved sib-pair test for linkage is introduced which is superior to the previously proposed tests. The test is derived from the standard chi-squared goodness of fit statistic by restricting the alternative hypothesis to the genetically possible. Critical values are given and exact power comparisons are made with the previously proposed tests. The new test is shown to be more powerful for finite samples as well as being asymptotically uniformly most powerful. © 1993 Wiley-Liss, Inc.  相似文献   
20.
Patients suffering from semantic dementia provide important constraints on theories of the structure and organisation of semantic memory. In this article we report one such patient, AM, whose progressive deterioration of semantics enables us to address the much-debated issue of whether conceptual structure is hierarchically organised. The hierarchical account predicts that brain damage should impair lower levels of the hierarchy (property information) before affecting higher level (category) information (Warrington and Shallice, Q. J. Exp. Psychol. 1975, 27, 635–657). We evaluate this prediction by repeated testing of AM in two studies—a semantic priming task and a verification task—over an 18 month period, contrasting the progressive deterioration of properties (functional and perceptual) and category relations (category co-ordinates and category labels). Properties were preserved longer than category information, arguing against a hierarchical account of semantic memory. In addition, functional properties were most robust to brain damage, supporting our claim that functional information plays a special role in semantic representations (Durrant-Peatfield et al., Proc. 19th Ann. Conf. of the Cognitive Science Society. Erlbaum, Mahwah, NJ, 1997, pp. 193–198. Tyler et al., Cognitive Neuropsychol. 1997, 14, 511–545).  相似文献   
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