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51.
Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa. 相似文献
52.
A retrospective longitudinal study of 105 penetrating keratoplasties for vascularized corneal opacities was done. The results of cases with an etiology of healed trachoma or healed corneal ulcers were compared. The vascularization was graded from Grade I to V depending on the quadrant and type of vascularization. Graft clarity of 2+ or more in cases of trachomatous opacity was achieved in 93% of cases and that after postinfectious opacity in 71.8%. Prognosis was poor in cases where deep vascularization was present in more than two quadrants or more than 180 degrees. 相似文献
53.
M S Sachdev H Kumar A K RoopJain R Arora V K Dada 《Indian journal of ophthalmology》1990,38(4):184-186
A case of destructive ocular myiasis resulting in complete loss of the globe in two days time is documented. To the best of our knowledge this is the first report of such a severe involvement in a healthy and non-compromised host. Mechanical removal and good local hygiene helped heal the wound. The larvae were isolated to be that of Chrysomyia bezziana (screwworm fly). This is possibly the first report of destructive ocular myiasis caused by Chrysomyia bezziana from the Indian subcontinent and the second in world literature. Infestation of human eyes with larvae of flies (myiasis) has been reported. Serious consequences of destructive myiasis are seen in emaciated and diseased patients. Only one report of total destruction of the globe by maggots of Chrysomyia bezziana exists in the literature. As in previous communications, the patient in this report had no predisposing factors both systemic and local. We here in document a case of orbital myiasis leading to rapid destruction of the globe within two days in a healthy and a non-compromised patient. 相似文献
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M. Barua R. Sinha A. Majumdar 《Indian journal of otolaryngology and head and neck surgery》1993,45(2):87-90
Between 1986–1990, 290 patients with squamouscell carcinoma of the hypopharynx were assessed at the S. S. K. M. Hospital Calcutta,
out of the total of 1460 number of Head Neck cancer, (19.8%). The most frequent initial symptom was a foreign body sensation
in the throat (70%), and males were affected more than females (9.8 : 1.2). The peak age incidence was found between 40 and
50 years (24%). Most of the patients came in advanced stages with cervical lymph node metastases (60%).
One interesting fact that came out from the present study is the Right pyriform fassa was more commonly affected than the
left in righthanded persons (56.9%). Though the reason is not clear it could be due to right — sided swallow, as one side
may be predominant in funtion. 相似文献
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