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11.
We assessed the efficacy and adverse effects of ivermectin for the treatment of chronic strongyloidiasis. Fifty patients were treated with a single dose of ivermectin at approximately 200 μg/kg, and the dose was repeated 2 weeks later. The eradication rate was 96% (48 of 50 patients) at 2 weeks after the first dose and 98% at 2 weeks after the second dose (49 of 50 patients). In the latter cases, no recurrence was noted at the end of the 4-month post-treatment follow-up period. The gastrointestinal symptoms observed most frequently before the treatment were borborygmus, constipation, and diarrhea. These symptoms improved in the majority of patients after the treatment. Side effects, including nausea and vomiting, occurred in 1 patient (2%), but these were mild and transient. Although abnormal values in laboratory tests were observed in 4 patients (8%), they were mild, and no particular clinical care was required. Thus, ivermectin showed an excellent antihelminthic effect, with little toxicity. Our results indicate that a regimen of two single doses of 200 μg/kg ivermectin, given 2 weeks apart, is clinically suitable for the treatment of chronic strongyloidiasis. Received: April 25, 2001 / Accepted: November 16, 2001  相似文献   
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The present experiment was conducted to examine the hypothesis that extended eye contact might intensify direct relations in a social encounter with another individual. Organized into same sex dyadic pairs, 64 students (32 male, 32 female) were divided into two groups (high- and low-eye contact) and assigned to either a positive or negative condition defined in terms of the verbal content of the confederate. With respect to the affective components of these dyadic interactions, it was found that under the positive evaluation condition, greater liking occurred in the high-eye contact group. In contrast, greater liking occurred in the low-eye contact group under the negative evaluation condition. Similar patterns were found with respect to the evaluation of "sincerity", "interest" and "attraction" toward the confederate. All these findings were in accordance with the hypothesis stated above. However, findings related to the qualification factor of the interaction as indexed by "skill of address", "attentiveness" and "confidence" were not in accordance with expectations. It was concluded, therefore, that increasing eye contact selectively intensifies the affective elements in a dyadic relationship while leaving the qualification aspects unaffected.  相似文献   
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Summary We have studied the structure of the two linear DNA plasmids, kl and k2, present in killer strains of Kluyveromyces lactis. Two killer strains of different origins, CBS 2359 and IFO 1267 were examined. For both strains, identical restriction maps of kl and k2 DNA were obtained. Several restriction sites previously reported for the kl DNA of the strain IFO 1267 have been confirmed. The molecular weights of these double-stranded DNAs were 8.8 kilobase pairs for kl and 13.4 for k2, as determined by electrophoresis of restriction fragments. The plasmid DNA from a nonkiller mutant, NK2/1, was also examined. In this mutant, the kl DNA was replaced by a smaller DNA (5.9 kilobase pairs), the k2 DNA being normal. Restriction enzyme analysis showed that the new plasmid DNA was also linear. Hybridization experiments demonstrated that it was derived from the kl DNA by deletion of a 2.9 kilobase pair segment from the central part of the kl DNA. The deleted segment carries a gene involved in toxin production, but is not related to immunity since the mutant is resistant to killers. The plasmid DNA of K. lactis showed no detectable sequence homology with the double stranded RNA of the killer system of Saccharomyces cerevisiae. Neither was any homology found with nuclear and mitochondria) DNA.  相似文献   
15.
The gold standard diagnostic method for sleep apnea syndrome(SAS) is overnight polysomnography(PSG), but is costly in terms of time and money. We studied the usefulness of a 24-hour ambulatory respirometer equipped with oximeter(Hotmate) for screening of SAS. Seventy-six cases of suspected SAS were enrolled(68 males and 8 females, mean age 51). The correlation between data from Hotmate and PSG was evaluated in 24 cases who underwent both of the tests for the final diagnosis of SAS. There was a good correlation between the two parameters of the data obtained by Hotmate(H) (H-apnea index(AI) vs H-desaturation index(DI)). Among 24 cases who underwent both Hotmate and PSG, there was a good correlation between the data from PSG and Hotmate(PSG-AI vs H-AI: r = 0.80, p < 0.001). Both sensitivity and specificity were highest when screening criteria of H-DI > 15 was utilized(sensitivity = 91.7%, specificity = 66.7%). Our findings suggest that the respiromonitor with oximeter is useful for the screening the patients with SAS.  相似文献   
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The atypical cells of CD30(+) cutaneous lymphoproliferative disorders (CD30CLD) are commonly of T-cell origin and frequently have a similar morphology as Hodgkin or Reed-Sternberg cells of Hodgkin's lymphoma (HL). HL is one of the tumors associated with CD30CLD. Although most studies support a B-cell derivation of the tumor cells in HL, recently a few cases of classical HL with T-cell genotype have been reported. We report a patient who presented with CD30CLD whose lymph nodes showed classical HL of mixed cellularity subtype at presentation. By single-cell PCR, the same clonal gene rearrangements of the T cell receptor-beta gene locus could be assigned to the CD30(+) and CD15(+) cells of both skin and lymph node. In a lymph node biopsy specimen taken in relapse after several courses of chemotherapy, the CD30(+) tumor cells were abundant. The T cell-derived tumor cells displayed aberrant expression of the Pax-5 gene in all specimens. A common clonal origin of both CD30CLD and HL of the lymph node in the patient presented here suggests that HL with T-cell genotype exists in association with CD30CLD as well as in sporadic cases and may share clonal origin with the skin tumor.  相似文献   
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Evidence for endocytosis-independent infection by human rotavirus   总被引:6,自引:0,他引:6  
Summary The effects of five lysosomotropic drugs (NH4Cl, chloroquine, methylamine, amantadine and dansylcadaverine) and cytochalasin B on human rotavirus (HRV KUN strain) and vesicular stomatitis virus (VSV Indiana strain) infection in monkey MA 104 cells were examined. These drugs had little effect on HRV yield but greatly reduced VSV yield. The results strongly suggest that HRV does not require endocytotic activity and intracellular acidic vesicles for the initial stage of infection and support our postulate that HRV enters the target cell by direct penetration of its nucleoid through the cell membrane.  相似文献   
20.
Orientia tsutsugamushi, an intracellular parasitic bacterium, comprises numerous strains of differing virulence. When BALB/c mice were infected intraperitoneally with this pathogen, a virulent strain known as Karp was found to multiply in the intraperitoneal macrophages and kill the mouse. In contrast, an avirulent strain, Kuroki, was shown to invade macrophages but be eliminated from the cells, allowing mouse survival. O. tsutsugamushi invades its host cell cytoplasm through phagocytosis and disruption of phagosomal membranes but some bacteria are then killed by phago-lysosomes within 1h of infection. Microscopic observations could not differentiate the Karp and Kuroki strains during entry and subsequent cell killing by phago-lysosomes. However, the Kuroki cells failed to divide and were markedly deformed following cytoplasmic invasion at several days post-infection. These findings suggest that macrophages have a mechanism to eliminate O. tsutsugamushi in the cytoplasm, if the invading bacteria escape phagosomal clearance, and that it is this mechanism that Kuroki does not survive. Additionally, significant levels of nitric oxide (NO) are produced in macrophages by Kuroki, but not by Karp. An NO synthase inhibitor, however, does not increase the growth of Kuroki, suggesting that NO is induced in a strain-dependent manner but does not effect proliferation.  相似文献   
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