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51.
PURPOSE: To describe a case of bilateral corneal ulcers caused by Pseudomonas in a disposable soft contact lens wearer. This case study discusses the role of patient examination, contact lens care instruction, and adequate patient supervision in reducing the risk of serious potential complications. METHODS AND RESULTS: A 17 year old student who had been using disposable soft contact lenses on an extended wear basis for 6 months presented complaining of pain in the left eye. When he was examined, a corneal ulcer with surrounding infiltrate was observed in the superior middle periphery of the left eye. Samples were collected for culture, and treatment with fortified cefalotin and gentamicin was started. After 8 hours the patient returned, now complaining of pain in the right eye. Examination of the right eye revealed a diffused keratitis with a mucopurulent discharge. A culture was taken, and the same treatment was instituted. The laboratory tests revealed Pseudomonas in both eyes. The bilateral corneal ulcers responded to therapy after 1 week of treatment. CONCLUSIONS: We discuss the factors involved in the occurrence of infectious keratitis in contact lens wearers, and stress that even disposable contact lens wear can be associated with serious complications. This case also highlights extended wear as one of the main risk factors for complications in disposable soft contact lens wear.  相似文献   
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The rates of reaction and the products formed when two vicinaldiol-epoxides derived from benz(a)an-thracene, anti-BA-3, 4-dioI1, 2-oxide (t-3, r-4-dihydroxy-t-1, 2-oxy-l, 2, 3, 4-tetrahydrobenz(a)anthracene)* and anti-BA-8, 9-diol 10, 11-oxide (r-8, t-9-dihydroxy-t-10,ll-oxy-8, 9, 10, ll-tetrahydro-benz(a)anthracene) reacted withDNA were studied in vitro and the results were compared withthose obtained in similar experiments using anti-BP-7, 8-diol9, 10-oxide (r-7, t-8-dihydroxy-t-9, 10-oxy-7, 8, 9, 10-tetrahydrobenzo(a)pyrene).The reactivities appeared to decrease in the order anti-BP-7,8-diol 9, 10-oxide > anti-BA-3, 4-diol 1, 2-oxide anti-BA-8,9-diol 10, 11-oxide. The diol-epoxides reacted to a similarextent with single- and with double-stranded DNA but reactionswith dGMP, at equivalent concentrations, were much slower thanwith DNA. With the diol-epoxides of benz(a)anthracene, two principaladducts were present in DNA hydrolysates and evidence was obtained,based on pK determinations before and after nitrous acid treatment,consistent with their being N2-guanine derivatives, analogousto the known DNA-reaction products of benzo(a)-pyrene 7, 8-diol9, 10-oxide.  相似文献   
53.
The radiographic findings of a 15-year-old Brazilian male with diagnosis of multiple myeloma are described. He presented with claudication and recent onset of tender painful swelling of the right mid leg. Radiographs showed wide spread soap bubble lesions of the skull, long bones, spine, pelvis, ribs, shoulders, and clavicles. The diagnosis was confirmed by the presence of a plasmacytoma on tissue biopsy (femur), serum IgG gammopathy and Bence-Jones proteinuria.Supported by grants (CA-20180 and CA-21765) from the National Cancer Institute and the American Lebanese Syrian Associated Charities (ALSAC)  相似文献   
54.
OBJECTIVE: To describe the role of magnetic resonance imaging (MRI) in the evaluation of patients with chronic and recurrent aseptic meningitis. METHOD: A retrospective study of five patients with aseptic meningoencefalitis diagnosed by clinical and CSF findings. CT scans showed without no relevant findings. RESULTS: MRI showed small multifocal lesions hyperintense on T2 weighted images and FLAIR, with mild or no gadolinium enhancement, mainly in periventricular and subcortical regions. Meningoencephalitis preceded the diagnosis of the underlying disease in four patients (Beh?et's disease or systemic lupus erythematosus). After the introduction of adequate treatment for the rheumatic disease, they did not present further symptoms of aseptic meningoencephalitis. CONCLUSION: Aseptic meningoencephalitis can be an early presentation of an autoimmune disease. It is important to emphasize the role of MRI in the diagnosis and follow-up of these patients.  相似文献   
55.
The Brucella abortus ribosomal protein L7/L12 is an immunodominant antigen and an interesting candidate for the development of oral live vaccines against brucellosis. Here, a recombinant Lactococcus lactis strain producing L7/L12 under the control of nisin inducible promoter was orally administered to BALB/c mice. Significant levels of anti-L7/L12 specific IgA detected in feces revealed an induced local humoral immune response. However, serum analysis did not reveal any anti-L7/L12 antibodies suggesting the absence of a systemic response. Nevertheless, the vaccinated mice showed a partial protective immunity against B. abortus virulent strain (S2308) challenged by intraperitoneal inoculation.  相似文献   
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Diwan  BA; Anderson  LM; Ward  JM 《Carcinogenesis》1997,18(10):2009-2014
Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after surgery and as a chemopreventive agent in women of child-bearing age. However, TAM therapy has been shown to result in an increased incidence of endometrial carcinoma in women. The present study was designed to investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g. to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their female offspring. Progressive proliferative hyperplasia of the oviduct was frequently seen in TAM-exposed offspring, reaching 100% incidence by 52 weeks in both treatment groups. These females also developed progressive proliferative uterine lesions, including moderate/severe cystic endometrial hyperplasia (34-50%) and polypoid adenomas (27-30%) between 53 and 78 weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest a strong association between transplacental TAM and reproductive tract abnormalities in female CD-1 mice.   相似文献   
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