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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   
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A group of patients with chronic gastric ulcers received a course of laser treatment with the use of laser on copper vapours. Gastric ulcer was exposed to radiation once in the course of 5 days, the single dose being equal to 10-15 J. Complete healing of the ulcerous defect was attained in 100 out of 110 patients examined. The results of laser therapy were found to be influenced by certain clinical characteristics, namely by age, ulcer size, duration of the last disease exacerbation, and acid-secreting function of the stomach.  相似文献   
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Available are two cases of Wilms's tumor with focal intestinal differentiation. Goblet- and endocrine-like cells as well as those similar to enterocytes were identified in one of the tumors upon electron microscopy. Squamous epithelial, cartilaginous cells, rabdomyoblasts presented in both cases. Problems of histogenesis and prognosis are under discussion.  相似文献   
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The paper covers a number of morphogenetic problems of endometrial cancer with reference to multidirectional differentiation of the uterine epithelium affected by tumor. Metaplastic changes of the endometrium observable in three basic variants (tubal, endocervical, squamous cell) can entail dysplasia with resultant malignant transformation. Endometrial cancer shows complex structure of the tumor with sings of multidirectional epithelial differentiation: endometrial, tubal, endocervical, squamous). Morphological features of the tumor and adjacent mucosa, assessed comparatively, suggest a close relationship between the direction of endometrial epithelium differentiation and the new growth histological structure.  相似文献   
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An infant of 10 months, suffering from scabies, has developed multiple involvements of the nail plates on the hands and feet, with detachment of some of them. A diagnostic error has promoted the dissemination of the process. The patient has been etiologically cured by a 10% water/soap suspension of benzyl-benzoate.  相似文献   
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59 angiomyolipomas were studied: immunohistochemistry (IHC) was used in 24 cases, electron microscopy (EM) in 6 cases. 57 tumors had a typical structure, 2 did not contain fat component. Premelanosomes were found by EM in one tumor. Smooth muscle actin was found in all tumor cells. Involvement of lymph nodes was observed in 2 patients. Histogenesis of this tumor is discussed.  相似文献   
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The optical coherence tomography method was explored for two-dimensional flow mapping of a highly scattering fluid in flow with complex geometry. Converging flow (capillary entry) with 4:1 constriction was used for demonstration of non-invasive and remote methods of mapping varying velocity profiles. Downstream of the geometry was scanned with approximately 10 x 10 x 10 microm3 spatial resolution and structural imaging of the lumen and images of one particular velocity were acquired. Stable concave, blunted and parabolic profiles are obtained at different distances of the inlet length. Application of the technique for the blood circulation is also discussed.  相似文献   
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