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Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m2 as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m2×2 doses of ara-C and 50 mg/m2 of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182  相似文献   
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Background: Reports of major and minor sequelae following lidocaine spinal anesthesia have generated interest in an alternative short-acting intrathecal agent. Of the available anesthetics suitable for short-duration spinal anesthesia, prilocaine is perhaps the most promising agent. However, data comparing the neurotoxicity of these agents are lacking. Accordingly, the present experiments investigate whether prilocaine and lidocaine differ with respect to sensory impairment and histologic damage when administered intrathecally in the rat.

Methods: Ninety rats were divided into three groups to receive an intrathecal infusion of 2.5% prilocaine in saline, 2.5% lidocaine in saline, or normal saline. The animals were assessed for persistent sensory impairment 4 days after anesthetic administration using the tail-flick test. Three days later, the animals were killed, and specimens of the spinal cord and nerve roots were obtained for histopathologic examination.

Results: Prilocaine and lidocaine produced equivalent elevations in tail-flick latency that differed significantly from saline. Histologic injury scores with prilocaine were greater than with lidocaine, but this difference did not reach statistical significance.  相似文献   

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Background:  Clusterin is a ubiquitous 80 kDa heterodimeric glycoprotein previously shown to be expressed on tumor cells of systemic and, to a lesser extent, primary cutaneous anaplastic large cell lymphoma (PC-ALCL). Lymphomatoid papulosis (LyP), an important differential diagnosis of ALCL, has been studied for clusterin expression in only a small number of cases. The aim of this study was to compare clusterin immunostaining patterns in LyP and other cutaneous histologic simulants with those of PC-ALCL.
Methods:  Formalin-fixed, paraffin-embedded sections of PC-ALCL (6), LyP (20), mycosis fungoides with large cell transformation (MF-LCT, 12), pityriasis lichenoides et varioliformis acuta (PLEVA, 12), arthropod bite reaction (ABR, 12) and lymphomatoid reactions (LR, 9) were immunostained for clusterin and evaluated for staining pattern and distribution. All diagnoses were made with clinicopathologic correlation.
Results:  Characteristic dot-like Golgi staining was identified in 10/20 LyP (50%), 4/6 PC-ALCL (67%) and 9/12 MF-LCT (75%). Two of 12 PLEVA (17%), 1 of 12 ABR (8%) and 2 of 8 LR (25%) had lymphocytes (< 25%) with diffuse cytoplasmic staining. Dermal dendritic cells stained strongly for clusterin. High background staining occurred in some cases.
Conclusion:  Clusterin immunostaining does not reliably distinguish between LyP, PC-ALCL or MF-LCT, but could distinguish LyP from its reactive histologic simulants.  相似文献   
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Abstract: Background : Women are increasingly being asked to consider participating in medical research. We sought to investigate views of women who participated in and declined to participate in a study that was part of a program of maternity care research. Methods : An exploratory study using focus group interviews and semistructured interviews was conducted. A purposive sample of 17 postnatal women who had participated in research, from a hospital in the North West of England, were interviewed. An open coding mechanism to identify emergent themes was used for the analysis of data. Results : Of women who had not declined to participate in any research, the following themes were identified: altruism versus self‐protection, enhanced versus inferior care, professional guidance versus self‐direction, and welcome versus unacceptable methodology. Of women who had participated in some research but declined to participate in other research, the following themes were identified: feeling disempowered by the process, inability to believe equipoise existed, and practical inconvenience. Conclusions : These findings suggest that although health care researchers adopt an individualistic approach to care, they may fail to adopt a similar approach within research. What is important and acceptable to women needs to be ascertained to develop appropriate research strategies. This plan will ensure that research is carried out to the highest ethical standard, which may increase recruitment rates.  相似文献   
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A number of eyelid lesions in early childhood, most commonly dacryoceles and hemangiomas, have been documented to cause astigmatic changes of the cornea. Juvenile xanthogranuloma (JXG) is typically reported to include both cutaneous skin and anterior ocular segment lesions. We report a case of a 10-month-old infant in which a subcutaneous JXG lesion of the lower eyelid resulted in visually significant astigmatic amblyopia.  相似文献   
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