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1.
Pityriasis rosea (PR) is a relatively common disease although its aetiology has not yet been identified. It occurs worldwide and there is no racial susceptibility factor. It usually affects teenagers and young adults between 10 and 35 years of age. Typical PR is much easier to diagnose than the rare atypical forms. We report a rare case of vesicular PR in a black woman who had vesicular lesions limited to her palms and soles in addition to regular typical lesions. We devised an efficient oral erythromycin treatment for this patient.  相似文献   
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
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In a study of cytokine production ex vivo by Borrelia burgdorferi-stimulated peripheral blood mononuclear cells from 27 patients with culture-positive erythema migrans, production of inflammatory cytokines predominated, particularly gamma interferon and, to a lesser degree, tumor necrosis factor alpha. In contrast, with the exception of interleukin-13, anti-inflammatory cytokine production was negligible. Thus, B. burgdorferi antigens in early Lyme disease often induce a strong inflammatory response.  相似文献   
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Strategies for controlling cat fleas, Ctenocephalidesfelisfelis (Bouché), have undergone dramatic changes in the past 5 yr. With the advent of on-animal treatments with residual activity the potential for the development of insecticide resistance increases. A larval bioassay was developed to determine the baseline susceptibility of field-collected strains of cat fleas to imidacloprid. All four laboratory strains tested showed a similar level of susceptibility to imidacloprid. Advantages of this bioassay are that smaller numbers of fleas are required because flea eggs are collected for the test. Insect growth regulators and other novel insecticides can also be evaluated. Using a discriminating dose, the detection of reduced susceptibility in field strains can be determined with as few as 40 eggs.  相似文献   
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Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
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The clinical manifestations of chronic disseminated histoplasmosis are non-specific and resemble those of other chronic infections and malignancies. We report the radiographic, sonographic and contrast-enhanced CT appearances of histoplasmosis in an adult male with non-insulin dependent diabetes mellitus, who was HIV negative and presented with weight loss and pyrexia. Imaging studies simulated tuberculosis with mediastinal lymphadenopathy, bilateral fibrotic lung lesions, hepatomegaly and bilateral hypoattenuating adrenal enlargement, without clinical or laboratory evidence of hypoadrenalism. Computed tomography-guided fine-needle aspiration biopsy of adrenal glands revealed Histoplasma capsulatum. We report our experience to increase awareness of the imaging spectrum of disseminated histoplasmosis and its similarity to tuberculosis as, with increasing incidence of AIDS, the chances of these infections are likely to increase. Moreover, awareness of this entity is important because it is known that untreated disseminated histoplasmosis is fatal.  相似文献   
10.
Post-colonoscopy surveillance interval for colorectal polyps depends on the size, number, and pathological classification of removed polyps. The risk of sporadic hyperplastic polyps (HPs) for developing colorectal adenocarcinoma remains debatable due to limited data. We aimed to evaluate the risk of metachronous colorectal cancer (CRC) in patients with sporadic HPs. A total of 249 patients with historical HP(s) diagnosed in 2003 were included as the disease group, and 393 patients without any polyp as the control group. All historical HPs were reclassified into SSA or true HP based on the recent 2010 and 2019 World Health Organization (WHO) criteria. Polyp size was measured under light microscope. Patients developed CRC were identified from the Tumor Registry database. Each tumor was tested for DNA mismatch repair proteins (MMR) by immunohistochemistry. Results showed that 21 (8%) and 48 (19%) historical HPs were reclassified as SSAs based on the 2010 and 2019 WHO criteria, respectively. The mean polyp size of SSAs (6.7 mm) was significantly larger than HPs (3.3 mm) (P<0.0001). For polyp size ≥5 mm, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for diagnosing SSA was 90%, 90%, 46%, and 99%, respectively. Left-sided polyps with size <5 mm were 100% of HPs. Five of 249 (2%) patients developed metachronous CRC during the 14-year follow-up from 2003 to 2017, including 2 of 21 (9.5%) patients with SSA diagnosed at intervals of 2.5 and 7 years, and 3 of 228 (1.3%) patients with HP(s) at 7, 10.3, and 11.9 years. Two of 5 cancers showed MMR deficiency with concurrent loss of MLH1/PMS2. Based on the 2019 WHO criteria, the rate of developing metachronous CRC in patients with SSA (P=0.0116) and HP (P=0.0384) was significantly higher than the control group, and no significant difference was observed between patients with SSA and with HP (P=0.241) in this cohort. Patients with either SSA or HP also had higher risk of CRC than average-risk US population (P=0.0002 and 0.0001, respectively). Our data add a new line of evidence that patients with sporadic HP are associated with above-average risk of developing metachronous CRC. Post-polypectomy surveillance for sporadic HP may be adjusted in future practice given the low but increased risk of developing CRC.  相似文献   
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