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91.
A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan. 相似文献
92.
Summary Two previously identified forms of macrophage were investigated in primary cultures of cerebral cortical cells. Dynamic features were revealed through time-lapse video recording and aspects of macrophage function were assessed. The two cell forms were shown to be different pre-mitotic stages of a single cell type. The cell cycle for these cells involved an initial large, flat, quiescent cell which retracted to yield a slightly rounded form with numerous processes. This latter form lost processes and developed profuse filopodia as it became very rounded just prior to division; both resulting daughter cells then regained the initial large flat appearance. These cells possessed several properties of macrophages, including phagocytosis, nucleoside diphosphatase enzyme, and CR3 receptors. These properties were transient, expressed just before and after mitosis, but subsequently down-regulated in the flat daughter cells. Because of this feature, it was difficult to determine the exact size of this cell population; however, the observed rate of proliferation suggests it may be substantial. It is suggested that these cells correspond to non-microglial macrophages of brain tissue and, because of their significant down-regulation, they may be difficult to detect. This may be important in studies of brain accessory immune cells in tissue culture. 相似文献
93.
E. Schuettpelz S. B. Hoot R. Samuel F. Ehrendorfer 《Plant Systematics and Evolution》2002,231(1-4):143-151
Using two molecular data sets, the plastid atpB-rbcL intergenic spacer region and the nuclear ribosomal internal transcribed spacer regions (ITS), the taxonomic affinities of
two newly available Anemone species from the Southern Hemisphere were tested. From previous work based on morphology and geographic distribution, it
was assumed that A. tenuicaulis from New Zealand was most closely related to the Tasmanian A. crassifolia, whereas the affinity of A. antucensis from Chile and Argentina was regarded as uncertain. Analyses of molecular sequence data from these and 18 other species of
Anemone s.lat. (with Clematis as outgroup) result in trees largely congruent with past analyses based on morphology and plastid restriction site data.
They strongly support A. richardsonii and A. canadensis (with boreal distributions in the Northern Hemisphere) as paraphyletic to a well supported Southern Hemisphere clade consisting
of A. antucensis and A. tenuicaulis. This group of four species is part of an otherwise predominantly Northern Hemisphere assemblage (subgenus Anemonidium s.lat., chromosome base number x=7), including A. narcissiflora, A. obtusiloba, A. keiskeana and A. (=Hepatica) americana. All other austral species included in the present sampling, A. crassifolia (Tasmania), A. knowltonia (=Knowltonia capensis), and A. caffra (both South African), form a separate clade, sister to A. (=Pulsatilla) occidentalis and other Northern Hemisphere anemones (subgenus Anemone s.lat., x=8). Possible phytogeographical links of the Southern Hemisphere species are discussed.
Received April 23, 2001 Accepted October 4, 2001 相似文献
94.
Trap sampling over reefs in deep (mean = 20 m) and shallow (mean = 10 m) waters along c. 1500 km of coastline in tropical north‐western Australia during both day and night and in wet and dry periods yielded 23 377 fishes, representing 32 families, 58 genera and 119 species. Individuals of the Serranidae, Lutjanidae, Lethrinidae and Carangidae contributed 88·9% to the total catch. The ichthyofaunal compositions of the Kimberley, Canning and Pilbara bioregions were relatively discrete. Species composition was influenced far more by location (latitude) than by water depth, period and time of day, and underwent a gradational change southwards. The latter change reflected differences in the trends exhibited by the relative abundances of certain species with increasing latitude and the confinement of other species largely to particular regions. The three most abundant species, i.e. Lethrinus sp. 3, Lutjanus carponotatus and Lethrinus laticaudis contributed 34·8, 20·8 and 11·6% to the total catch, respectively. The first species was rarely recorded in the two most northern locations and was abundant in the four most southern locations, whereas the last two species were relatively more abundant in northern than in southern locations. Lutjanus bitaeniatus and Lutjanus johnii were found exclusively at the two locations in the Kimberley region, whereas Abalistes stellatus, Pentapodus emeryii and Lethrinus nebulosus were not caught in this region but were found in both locations of the Canning and Pilbara regions. The species composition in deep and shallow waters at each location almost invariably differed significantly between day and night and between dry and wet periods, with species such as L. bitaeniatus, L. johnii, Lutjanus sebae and A. stellatus being more abundant over deep reefs, whereas L. carponotatus, L. laticaudis, Siganus fuscescens and Lethrinus lentjan were more numerous over shallow reefs. Species such as L. johnii and Lethrinus atkinsoni were relatively more important in night‐time than daytime catches, whereas the reverse applied to Lethrinus lentjan, L. laticaudis and Choerodon cyanodus. Lethrinus sp. 3 and L. laticaudis were relatively more important in catches during the dry than wet period. 相似文献
95.
Distinguishing between cryptic species is a perennial problem for biologists. Bombus ruderatus and Bombus hortorum are two species of bumblebee, which can be indistinguishable from their morphology. The former species is in decline, whereas the latter is ubiquitous. In the UK, isolated records of B. ruderatus occur amongst many for B. hortorum. For ecological studies of B. ruderatus to be feasible, the two species need to be reliably distinguishable. We present a diagnostic tool for quick and reliable identification of problematic individuals based on a restriction enzyme digest of the cytochrome b region of mitochondrial DNA. 相似文献
96.
Chien-Hung Liu Wen-Ming Chen Jo-Shu Chang 《World journal of microbiology & biotechnology》2007,23(5):633-640
Acidic lipase finds its commercial values in medical applications and bioremediation of food wastes. In this work, approaches
for rapid screening of lipase-producing bacteria were developed and the feasibility assessment of the screening methods was
performed. From food waste samples, the proposed screening procedures allowed isolation of sixteen pure bacterial strains
expressing higher lipase activity at acidic pH (pH 6.0) than at alkaline pH (pH 9.0). To enhance the accuracy of lipase activity
determination under acidic conditions, a novel assay procedure was also developed by deactivating lipase activity by microwave
treatment prior to back titration. This additional step could minimize interferences arising from residual lipase activity
during conventional direct back-titration methods in measuring lipase activity at acidic pH. Using the four strategies proposed
in this work, the best acidic-lipase-producing isolate was obtained by strategy C (SSC) and was identified as Aeromonas sp. C14, displaying an optimal lipase activity of 0.7 U/ml at an acidic pH of 6.0. 相似文献
97.
Isabelle Matricon 《Cell and tissue research》1973,136(4):569-578
Résumé L'épithélium pharyngien d'Alcyonidium polyoum possède des cellules pourvues d'une très grande vacuole. L'incompressibilité du liquide vacuolaire permet un élargissement brusque de l'organe lors de la contraction du manchon musculaire strié qui enserre cette vacuole. Les fibres musculaires sont insérées sur le plasmalemme apical par des filaments unitifs. Le point d'attache est relié à la lame amorphe du cell-coat qui entoure les microvillosités par des fibrilles, réalisant probablement une liaison mécamique plus efficace. Le reticulum sarcoplasmique porte des ribosomes. Le cytoplasme apical renferme des vésicules de diverses catégories.
Some ultrastructural data about a myoepithelium: The pharynx of a bryozoan
Summary Pharyngeal cells of Alcyonidium polyoum (Bryozoa) are provided with very large vacuoles. Each vacuole is enveloped by a thin layer of striated muscle, whose contraction enlarges the organ. Filaments join the muscular elements to the apical plasmalemma. This point of muscular insertion is connected by fibrils with the amorphic lamina of cell-coat which surrounds the microvilli. Ribosomes are often found on dyads. Various vesicles are located in the apical cytoplasm.相似文献
98.
Sensitivity to and requirement for iron in Plantago species 总被引:1,自引:0,他引:1
99.
R.J. Dobson A.P. Dargantes R.T. Mercado 《International journal for parasitology》2009,39(10):1115-1123
Simple demographic and infectious disease models of buffaloes and other domestic hosts for animal trypanosomosis (surra) caused by Trypanosoma evansi were developed. The animal models contained deterministic and stochastic elements and were linked to simulate the benefit of control regimes for surra in village domestic animal populations in Mindanao, Philippines. The impact of the disease on host fertility and mortality were key factors in determining the economic losses and net-benefit from the control regimes. If using a high (99%) efficacy drug in surra-moderate to high risk areas, then treating all animals twice each year yielded low prevalence in 2 years; targeted treatment of clinically sick animals, constantly monitored (monthly), required 75% fewer treatments but took longer to reach a low prevalence than treating all animals twice each year. At high drug efficacy both of these treatment strategies increased the benefit over untreated animals by 81%. If drug efficacy declined then the benefit obtained from twice yearly treatment of all animals declined rapidly compared with regular monitoring and targeting treatment to clinically sick animals. The current control regimen applied in the Philippines of annual sero-testing for surra and only treating sero-positive animals provided the lowest net-benefit of all the control options simulated and would not be regarded as effective control. The total net-benefit from effective surra control for a typical village in a moderate/high risk area was 7.9 million pesos per annum (US $158,000). The value added to buffaloes, cattle, horses, goats/sheep and pigs as a result of this control was US $88, $84, $151, $7, $114 per animal/year, respectively. 相似文献
100.
Fátima H. Vaz Patrícia M. Machado Rita D. Brand?o Cátia T. Laranjeira Joana S. Eugénio Aires H. Fernandes Saudade P. André 《The journal of histochemistry and cytochemistry》2007,55(11):1105-1113
Only 20-25% of families screened for BRCA1/2 mutations are found positive. Because only a positive result is informative, we studied the role of BRCA1/2 immunohistochemistry as an additional method for patient selection. From 53 high-risk-affected probands, 18 (34%) had available paraffin blocks of their tumors and were selected for this study. Mutation screening was done by conformation-sensitive gel electrophoresis and multiplex ligation-dependent probe amplification. For immunohistochemistry, 21 neoplastic specimens (15 breast carcinomas, 5 ovary neoplasms, and 1 rectal adenocarcinoma) were analyzed with BRCA1 (monoclonal antibody, Ab-1, oncogene) and BRCA2 (polyclonal antibody, Ab-2, oncogene) antibodies. Absence of the BRCA1 protein was confirmed in negative tumors by Western blotting. Seven patients were positive for BRCA1/2 mutations: 5 for BRCA1 and 2 for BRCA2. Four out of five positive patients had tumors negative for BRCA1 immunostaining, and the remaining 13 BRCA1-negative patients had positive BRCA1 immunostaining in all tumor samples. Sensitivity to predict for BRCA1 mutation carriers was 80%, and specificity was 100%, with a positive predictive value of 100% and a negative predictive value of 93%. This correlation was statistically significant (p=0.001). No correlation was observed for BRCA2. If larger studies confirm these results, high-risk patients with BRCA1-negative tumors should be screened first for this gene. 相似文献