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971.
Background  Patients with psoriasis experience remission and gradual reappearance of erythematous and scaly plaques and require individualized treatment over time. A goal of psoriasis treatment is to provide optimal efficacy with a flexible therapeutic regimen that may include treatment pauses.
Objectives  To determine whether patients receiving initial treatment with etanercept who then pause therapy would subsequently recapture response during re-treatment.
Patients and methods  A post-hoc analysis of 226 patients with moderate-to-severe psoriasis from a large multicentre trial was performed. Patients had received etanercept 50 mg twice weekly subcutaneously until a target clinical response had been achieved, then had paused treatment and eventually relapsed. They were then re-treated with etanercept 25 mg twice weekly. The number of patients recapturing a Physician Global Assessment (PGA) of psoriasis rating of ≤ 2 (clear, almost clear or mild) on first re-treatment was assessed. Patient satisfaction during the initial treatment and first re-treatment period was also determined.
Results  A total of 187 (83%) patients recaptured the target clinical response of a PGA of ≤ 2 after re-treatment. The majority of patients [219 of 226 (97%)] reported satisfaction with etanercept re-treatment. No new safety concerns emerged during re-treatment.
Conclusions  In this post-hoc analysis, patients with psoriasis who were re-treated with etanercept 25 mg twice weekly effectively recaptured clinical responses that patients found satisfactory. A flexible treatment option is available to dermatologists and patients for individualized care.  相似文献   
972.
Background  Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) is a synthetic fragrance ingredient. Case reports of allergy to HICC appeared in the 1980s, and HICC has recently been included in the European baseline series. Human elicitation dose–response studies performed with different allergens have shown a significant relationship between the patch-test threshold and the repeated open application test (ROAT) threshold, which mimics some real-life exposure situations. Fragrance ingredients are special as significant amounts of allergen may evaporate from the skin.
Objectives  The study aimed to investigate the relationship between elicitation threshold doses at the patch test and the ROAT, using HICC as the allergen. The expected evaporation rate was calculated.
Materials and methods  Seventeen HICC-allergic persons were tested with a dilution series of HICC in a patch test and a ROAT (duration up to 21 days). Seventeen persons with no HICC allergy were included as control group for the ROAT.
Results  The response frequency to the ROAT (in μg HICC cm−2 per application) was significantly higher than the response frequency to the patch test at one of the tested doses. Furthermore the response rate to the accumulated ROAT dose was significantly lower at half of the doses compared with the patch test. The evaporation rate of HICC was calculated to be 72% over a 24-h period.
Conclusions  The ROAT threshold in dose per area per application is lower than the patch test threshold; furthermore the accumulated ROAT threshold is higher than the patch test threshold, which can probably be explained by the evaporation of HICC from the skin in the open test.  相似文献   
973.
A mutant form of ammodytoxin A, a neurotoxic phospholipase A2 from the venom of the long nosed viper Vipera ammodytes ammodytes, was prepared by site-directed mutagenesis, conjugated to a nanogold particle and inoculated into the antero-lateral aspect of one hind limb of female mice. Eight hours later the mice were killed, the soleus muscles of both ipsi- and contra-lateral hind limbs were removed, exposed to a silver enhancing medium and then prepared for transmission electron microscopy. Silver-enhanced particles were subsequently found concentrated in the peri-synaptic area, particularly within the synaptic gutter and the deep synaptic folds, and in many cases had been taken up into the cytoplasm of the terminal boutons of the motor axon. The results suggest that the presynaptic neurotoxicity of snake venom phospholipases A2 involves several components of the neuromuscular apparatus, including intracellular organelles of the motor nerve terminal.  相似文献   
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The purpose of this study was to evaluate a single-session peer-led safer sex intervention, based on the Information-Motivation-Behavioral Skills theoretical model, for college students residing in campus residence halls. Participants (N = 108) were assigned to either an hour long control or 5-module intervention session. Compared to the control condition, the intervention increased participants’ information and women’s subjective norms about preventative behavior. Both the control and intervention sessions increased intentions to perform preventative behaviors (e.g., keep condoms available). These preliminary results suggest that this intervention is promising for increasing constructs associated with safer sexual behavior and could easily be implemented by residence hall staff.  相似文献   
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