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排序方式: 共有1365条查询结果,搜索用时 31 毫秒
91.
92.
Krenn L Presser A Pradhan R Bahr B Paper DH Mayer KK Kopp B 《Journal of natural products》2003,66(8):1107-1109
A sulfated emodin glucoside, emodin 8-O-beta-D-glucopyranosyl-6-O-sulfate (1), was isolated from the roots of Rheum emodi in an investigation of the active constituents of this Nepalese medicinal plant, and its structure was determined by spectroscopic and chemical methods. Additionally, two rare auronols, carpusin (2) and maesopsin (3), besides other anthraquinones and phenolics, were isolated and identified. Compounds 2 and 3 showed significant antioxidant activity in the DPPH assay, while chrysophanol, physcion, and emodin and their 8-O-glucosides were found to be inactive. 相似文献
93.
PURPOSE: To determine the frequency and types of lens-induced glaucoma (LIG), reasons for late presentation and outcome of current management. METHODS: Prospective case series of 413 patients/eyes with LIG over a 12-month period in 1998; 311 of these patients underwent cataract surgery. Visual acuity and intraocular pressure (IOP) were pre- and postoperatively assessed. RESULTS: Four hundred and thirteen (1.5%) of 27,073 senile cataracts seen in the outpatient department of Sagarmatha Choudhary Eye Hospital, Lahan, Nepal presented with LIG. There were 298 (72%) phacomorphic cases and 115 (28%) phacolytic glaucoma. Pain for more than 10 days was reported by 293 (71%) patients. The majority, 258 (62.4%), travelled a distance of more than 100 kms to the hospital. The major reasons for late presentation were "no escort" in 143 (34.6%) and "lack of money" in 128 (31.0%) cases. At presentation the IOP was more than 30 mm Hg in 327 (79%) eyes. Following cataract surgery, 251 (80.7%) had 21 mm Hg or less at discharge. The visual acuity was hand-movement or less before surgery in all eyes; at discharge 120 of 311 operated eyes (38.6%) achieved 6/60 or better, 97 (31.2%) less than 6/60, and 94 (30.2%) less than 3/60. The main causes for poor outcome in 94 cases were optic atrophy in 32 (34%) eyes, uveitis in 25 (26.6%)eyes and corneal oedema in 24 (25.5%) eyes. CONCLUSION: The results highlight the importance of early diagnosis and treatment of visually disabling cataract. There is a need to educate both the patient and the cataract surgeon of the dangers of lens-induced glaucoma and of the poor outcome if treatment is delayed. 相似文献
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96.
Sultan A. Pradhan Rajan Khannan Biswajyoti Hazarika Meena Desai 《Indian journal of otolaryngology and head and neck surgery》2007,59(2):168-170
Epithelial-myoepithelial carcinoma is a rare salivary gland tumor. It comprises less than 1% of all salivary gland tumors.
It generally arises from the parotid gland. Unusual sites of occurrence include sinonasal tract, lung, trachea, lacrimal gland
and breast. Histopathologically epithelial-myoepithelial carcinoma comprises a dual population of ductal and myoepithelial
cells. We report an extremely rare case of epithelial-myoepithelial carcinoma occurring in the sinonasal tract of young man. 相似文献
97.
98.
P Pradhan B Jernstr?m A Seidel B Nordén A Gr?slund 《Chemical research in toxicology》1999,12(5):403-411
The binding conformations of single anti- and syn-BPDE-N2-dG adducts in oligonucleotides of varying base composition have been studied by induced circular dichroism (ICD) and light absorption spectroscopy. The sign of the ICD in single-stranded oligonucleotide adducts correlates with the absolute configuration of the cyclohexyl moiety of the BPDE. Adducts in oligonucleotide duplexes with UV lambdamax <350 nm exhibiting a significant duplex-induced positive ICD should have a minor groove location as the predominant conformation. Those with UV lambdamax >350 nm exhibiting either positive or negative contributions to the ICD should have intercalated binding as the predominant conformation. The magnitude of the ICD is dependent on the sequence context of the adducted strand and the particular BPDE-adduct isomer under study. In some cases, the results suggest structural heterogeneity. For instance, the (+)- and the (-)-trans-anti-BPDE-N2-dG adducts in duplexes where a dT flanks the lesion site exhibit weak positive ICD or negative ICD. These results reflect a bimodal conformational adduct distribution with contributions from both externally and internally located adducts. A key observation for the (+)-cis-syn-BPDE-N2-dG complexes in 5'-d(TGC) and 5'-d(CGC) sequence contexts is that the near-UV absorption spectra showed distinct bands corresponding to minor groove binding (lambdamax congruent with 346 nm) as well as intercalative binding (lambdamax congruent with 354 nm). Evidence for an equilibrium between the different modes of localization is provided by the results from the temperature dependence of the near-UV absorption and ICD characteristics of (+)-cis-syn-BPDE-N2-dG complexes in 5'-d(TGC) and 5'-d(CGC) sequence contexts, respectively. 相似文献
99.
T. S. Anand Tapaswini Pradhan V. P. Singh Rita Malik 《Indian journal of otolaryngology and head and neck surgery》1999,51(3):69-71
Melanotic neruoectodermal tumour of infancy is an uncommon pigmented neural crest derivative. It is usually found affecting children aged one year or less. We present a case report of a four month old male infant with this tumour arising from the right maxilla showing extensive involovement of the surrounding bony and soft tissue structures. 相似文献
100.
Nityananda Pradhan Sulochana D. Moro Aruna S. Srinivasan 《Drug development research》1989,18(2):113-118
Locomotor behavior was studied with the use of automated devices in chronic imipramine- and haloperidol-treated Sprague Dawley rats. The biphasic response to apomorphine was only preserved in the control rats. The response to low dose apomorphine challenge was attenuated by chronic imipramine and haloperidol administration. There were no significant changes in motility responses to high dose apomorphine challenges between the control and experimental groups. The results suggest the involvement of postsynaptic Dopamine receptors (D2) in the loss of response to low dose apomorphine. 相似文献