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101.
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Adenoid cystic carcinoma is a rare variety of Ceruminoma, arising from the glandular elements of the External Auditory Canal. A case of Adenoid cystic carcinoma of the external auditory canal is reported, to recapitulate clinical features and management problems of the tumour at this site. The controversies in nomenclature, histopathology, and management are discussed.  相似文献   
103.
Vincristine pharmacokinetic, tumour uptake and therapeutic characteristics were investigated here in order to elucidate the processes underlying the enhanced efficacy observed for vincristine entrapped in small (120 nm) distearoylphosphatidylcholine/cholesterol liposomes. Plasma vincristine levels after intravenous (i.v.) injection are elevated more than 100-fold in the liposomal formulation compared with free drug in tumour-bearing as well as non-tumour-bearing mice over 24 h. Biodistribution studies demonstrate that the extent and duration of tumour exposure to vincristine is dramatically improved when the drug is administered i.v. in liposomal form. Specifically, 72 h trapezoidal area under the curve values for liposomal vincristine in the murine L1210 ascitic and B16/BL6 solid tumours are 12.9- to 4.1-fold larger, respectively, than observed for free drug. Similar to previous results with the L1210 model, increased drug delivery to the B16 tumour results in significant inhibition of tumour growth, whereas no anti-tumour activity is observed with free vincristine. Comparisons of drug and liposomal lipid accumulation in tumour and muscle tissue indicate that the enhanced efficacy of liposomal vincristine is related predominantly to drug delivered by liposomes to the tumour site rather than drug released from liposomes in the circulation. Consequently, improvements in liposomal vincristine formulations must focus on factors that increase uptake of liposomes into tumour sites as well as enhance liposomal drug retention in the circulation.  相似文献   
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BACKGROUND: Shoe dermatitis is a form of contact dermatitis resulting from exposure to shoes. Different chemicals, in conjunction with a hot and humid environment within the shoe, give rise to allergic or irritant dermatitis. Allergic shoe dermatitis is commonly caused by constituents of rubber, leather, adhesives, and rarely by linings and dyes. AIM: To determine the frequency of various allergens in shoe dermatitis in our patients. METHODS: One hundred and nine patients suspected of having contact dermatitis due to shoe allergens were included. All patients were patch tested with the Shoe series and European Standard series. Patches were applied on the upper back and removed after 48 h. Results were read at 48, 72, and 120 h and interpreted according to International Contact Dermatitis Research Group (ICDRG) criteria. RESULTS: Of the 119 patients, 87 (73%) reacted positively to various allergens, 48% of whom showed polysensitivity. Glues (33.6%), particularly para-tert-butylphenol formaldehyde resin (PTBP-FR) (26.9%), were the leading cause of shoe dermatitis. Other allergens were leather chemicals (26.4%), potassium dichromate (16.18%), rubber allergens (7.6%), and dyes (7.6%). Shoe scrapings tested positive in 26.3% of patients. Other common allergens were nickel sulfate (22.7%), neomycin sulfate (10.1%), and cobalt chloride (8.4%). CONCLUSIONS: Considering the diversity of allergens, all patients presenting with shoe dermatitis should be patch tested with the Shoe series and a standard series to determine the etiologic allergens.  相似文献   
107.
Relapsed and late-onset Nipah encephalitis   总被引:3,自引:0,他引:3  
An outbreak of infection with the Nipah virus, a novel paramyxovirus, occurred among pig farmers between September 1998 and June 1999 in Malaysia, involving 265 patients with 105 fatalities. This is a follow-up study 24 months after the outbreak. Twelve survivors (7.5%) of acute encephalitis had recurrent neurological disease (relapsed encephalitis). Of those who initially had acute nonencephalitic or asymptomatic infection, 10 patients (3.4%) had late-onset encephalitis. The mean interval between the first neurological episode and the time of initial infection was 8.4 months. Three patients had a second neurological episode. The onset of the relapsed or late-onset encephalitis was usually acute. Common clinical features were fever, headache, seizures, and focal neurological signs. Four of the 22 relapsed and late-onset encephalitis patients (18%) died. Magnetic resonance imaging typically showed patchy areas of confluent cortical lesions. Serial single-photon emission computed tomography showed the evolution of focal hyperperfusion to hypoperfusion in the corresponding areas. Necropsy of 2 patients showed changes of focal encephalitis with positive immunolocalization for Nipah virus antigens but no evidence of perivenous demyelination. We concluded that a unique relapsing and remitting encephalitis or late-onset encephalitis may result as a complication of persistent Nipah virus infection in the central nervous system.  相似文献   
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Thirty patients with localised stable vitiligo were selected from the Out Patient Department for cosmetic tattooing. Of them, 19 cases (63.3%) had skin patches, 9 cases (30%) had mucosal patches, and 2 cases (6.7%) had both skin and mucosal involvement. After complete clinical evaluation, cosmetic tattooing was performed on these patients, and they were followed up for 6 months. As results, 23 cases (76.7%) had excellent color matching, 2 cases (6.7%) had good color matching, and 5 cases (16.6%) had pigment shedding. Excellent results were seen in all mucosal patches. Dark complexion cases showed better results than fair complexion ones.  相似文献   
110.
Picobirnaviruses are a group of unclassified, non-enveloped, small spherical viruses, 35-41 nm in diameter without any apparent surface morphology. They have characteristic bisegmented double stranded RNA genome of two types namely large profile (2.3-2.6 kbp for the larger and 1.5-1.9 kbp for the smaller segment, respectively) or small profile (1.75 and 1.55 kbp for segments 1 and 2, respectively). Human picobirnaviruses (n=12 positives; 2/56 diarrhoeic children and 10/607 non-diarrhoeic children) with large (n=11) or small (n=1) genome pattern were observed in faecal specimens of children from a slum community by silver stained PAGE gels. Faecal specimen from four asymptomatic cases (P597_02_IND, K135_02_IND, A373_03_IND, A356_03_IND) and one diarrhoeic case (K135_03_IND) had genogroup I picobirnaviruses (1-CHN-97 like) showing amplicons within the 201 bp region, with primers PicoB25-PicoB43, targeting the conserved domain of RNA-dependent RNA polymerase (RdRp) gene. It was interesting to note that only the PBV strain P597_02_IND from Kolkata with large genome was closely related to a reported strain (similarity with 2-GA-91 from USA was 87% at the nucleotide level and 90% at the amino acid level). Sequence analysis showed three conserved amino acid domains as well as a highly conserved D-S-D motif, characteristic of RNA-dependent RNA polymerase gene of bisegmented, double stranded RNA viruses. Sequence data of the picobirnavirus A356_03_IND indicated strong heterogeneity with all other picobirnavirus strains sequenced till date. After nearly a decade a genogroup II picobirnavirus strain (R227_03_IND) was isolated from a diarrhoea case in the community, with small genome profile and amplified with specific primers PicoB23-PicoB24; but the sequence data showed that it was divergent from the hitherto reported prototype strain 4-GA-91 of genogroup II human picobirnaviruses.  相似文献   
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