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Cabuamine is identified as O-methyl-hydrogeno akuammine.  相似文献   

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Candida albicans is an opportunistic yeast. Its pathogenicity is linked to the susceptibility of the host surface as well as to particular factors of the strain: adhesion, filamentous growth and secretion of proteolytic enzymes. Chlorhexidine digluconate is an antiseptic with fungicidal properties. The action of the antiseptic on the growth of the yeast shows a minimal inhibitory concentration (MIC) at 50 μg·mL−1 and a minimal fungicidal concentration (MFC) at 100 μg·mL−1. The consequences of antiseptic treatment are studied using two indicators of pathogenicity: filamentation and the secretion of acid proteinase. Concerning the morphological indicator, a complete inhibition of filamentation for antiseptic concentration far below the MIC is observed; concerning the biochemical indicator, the results show a maintenance of proteolytic activity for concentration equal to the MIC and a disappearance of this activity between the MIC and the MFC. Concerning the proteolytic activity, Skim Milk (Difco) was substituted for bovine serum albumin with success. This mixture of casein allows to use a cheaper and more easily available substrate.  相似文献   

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The study of the different nitrogen fractions of Pinus canariensis during seed germination and seedling development indicates a progressive hydrolysis of the insoluble fraction. Arginine is quantitatively one of the most important amino acids in seed proteins.  相似文献   

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BackgroundInvasive Candida disease (ICD) is the most common cause of endogenous endophthalmitis. There are two characteristic ocular signs: Candida chorioretinitis defined as retina and choroid lesions without vitreal involvement, and Candida endophthalmitis defined as chorioretinitis with extension into the vitreous with characteristic fluffy balls. The most common visual symptoms are blurred vision and floaters.AimsTo define in which patients with ICD a surveillance ophthalmoscopic examination should be done.MethodsWe searched the PubMed/Medline data base Candida endophthalmitis in adult and paediatric patients with ICD.Results and conclusionsThe need of ophthalmoscopic examination in patients with ICD is controversial, partly due to the fact that early antifungal treatment leads to a significant decrease of endogenous Candida endophthalmitis. Routine ophthalmoscopic examination seems of little value in patients with positive blood culture, with early implementation of antifungal treatment, without symptoms of ocular infection and without impairment of the level of consciousness during the episode. However, ophthalmoscopic examination should be performed in children with candidemia and critically ill patients with documented ICD, in the second week of treatment, especially in echinocandin treatment.  相似文献   

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Remains of vertebrates of Villafranchian age have been found in the Nuraghe Su Casteddu (Nuoro, Sardinia) formation. The fossiliferous layer contain a rich fauna of continental molluscs. The composition of the vertebrate fauna is as follows: Rana sp., ? Coluber sp., Aves indet., Episoriculus aff. gibberodon PETENYI, Talpa sp., Chiroptera indet. and Rodentia indet. It is the first discovery of Villafranchian vetebrates in Sardinia.  相似文献   

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BackgroundCandida albicans has a variety of virulence factors, including secreted aspartyl proteases, which are determinant factors in the pathogenesis of this yeast in immunocompromised patients.AimsProteinase activity was identified in C. albicans strains isolated from the oral cavity of immunocompromised patients with cancer, diabetes and HIV+, with oral candidiasis and in healthy subjects.MethodsTwo hundred and fifty C. albicans strains were analyzed, distributed in 5 different groups: patients with cancer, diabetes, HIV+, with oral candidiasis and healthy subjects.ResultsProteolytic activity was identified in 46% of the strains from cancer patients, 54% from HIV+ patients, 60% from diabetics, 70% from oral candidiasis patients, and 42% from healthy subjects. Activity was higher in strains from immunocompromised and oral candidiasis patients than in healthy subjects. Differences were observed between the candidiasis-healthy, candidiasis-HIV+, and diabetic-healthy groups. No differences were observed between the oral candidiasis, diabetes and cancer patients, between the diabetes and HIV+ patients, or between the cancer patients, HIV+ patients and healthy subjects.ConclusionsThe present results suggest that although secreted aspartyl proteases are important in the pathogenesis of C. albicans, their activity depends on host conditions.  相似文献   

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J. Tesarik 《Andrologie》2000,10(3):289-291
Anin-vitro culture technique, previously tested with germ cells from men with complete spermatogenesis, was applied in assisted reproduction treatment for cases of meiotic and postmeiotic maturation arrest. Some primary spermatocytes from men with maturation arrest at the pachytene stage developed up to the late elongated spermatid stages and were capable of fertilizing the spouse’s oocytes and of giving rise to embryos that were transferred into the spouse’s uterus and subsequently developed to term. In other cases, round spermatids blocked in vivo before the process of spermiogenesis developed to elongated spermatidsin vitro; with the use of suchin-vitro formed spermatids, the first term pregnancies in cases of complete spermiogenesis arrest were achieved. These findings show that certain in-vivo developmental blocks in male germ cells from patients with severe testiculopathies can be overcome byin-vitro culture, probably by modifying control mechanisms acting at developmental checkpoints.  相似文献   

11.
Seven daunorubicin analogs containing α-l-, α-d-, and β-d-glycosidic linkages, in which the natural occurring sugar (l-daunosamine) was replaced by diastereo-isomeric 3-amino-2,3,6-trideoxyhexoses (3-epi-l-daunosamine, d-acosamine, d-daunosamine, d-ristosamine, and 3-epi-d-daunosamine), were prepared. In all cases, glycosidation with daunomycinone was performed in the presence of p-toluene-sulfonic acid starting from 1-O-acetyl-2,3,6-trideoxy-4-O-p-nitrobenzoyl-3-trifluoroacetamidohexopyranoses (prepared from the corresponding methyl 3-amino-2,3,6-trideoxyhexopyranosides) or from 1,5-anhydro-2,3,6-trideoxy-4-O-p-nitrobenzoyl-3-trifluoroacetamidohex-1-enitols (prepared from glycals or pseudoglycals, the 3-amino group being introduced by substitution with sodium azide and subsequent reduction). Glycosidation was followed by removal of the protecting groups.  相似文献   

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This review gives a synthesis on the present knowledge on the use of several electrophoretic markers in examining speciation and taxonomy in baboons (genus Papio, Mendrillus and Theropithecus). In the various species studied, the amplitude of variation is small and the average rate of individual heterozygosity low; this seems partly due to the inbreeding which occurs within the groups. In these sub-populations, and when the frquencies are in equilibrium, it is possible to calculate the number of genetic migrants by generation between groups, which averages 3–18% according to species. The genetic distances between species allow one to establish in the genus Papio that the species P. hamadryas is the most differentiated and on the whole these species are comparable to geographical races of a polytypic species according to the measures obtained. Calculation of electrophoretic distances shows tht within Papio both P. papio and P. anubis are indistinguishable and that the three other species. P. cynocephalus, P. ursinus and P. hamadryas, diverge from this basic group. According to these criteria, both Mandrillus species diverge on the average of 30% of their genes, and according to the paleontological dates of divergence between Papio and Theropithacus, Papio would have appeared approximately 3.5 million years ago, a date in agreement with the information obtained from fossils. The electrophoretic study of inter-specific hybrids allows the intensity of the migratory flux betwen the different groups of Papio anubis and P. hanadryas in natural conditions to be calculated, and shows a partial inhibition of the paternal component of hybrids P. anubix × P. cynocephalus. It is concluded that two interesting research problems are the study of inbreeding in the different groups, and the influence of the genetic regulation in the evolution of various species. The evolution of different species within the group seems to constitute an excellent animal model from the diversification of fossils hominids during the Pleistocene epoch.  相似文献   

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IntroductionInfluenza is one of the diseases with the greatest epidemiological impact and of maximum relevance in the management of health services. The flu vaccine can have great variability each season, so our objective was to find out the effectiveness of the flu vaccine for the 2017/2018 season for the prevention of severe cases of flu in people over 65 years of age in a 385-bed acute general hospital.Material and methodStudy of cases and controls. All hospitalized patients with laboratory-confirmed influenza older than 65 years during the 2017/2018 season were included. Those who met the criteria for a severe case of influenza were considered cases. Those who did not meet the severity criteria were considered controls. Factors associated with the development of severe influenza were calculated.ResultsThe median age was 68 years (SD 91.87). The attack rate was 0.23 per hundred inhabitants and the vaccine effectiveness was 38%. The vaccinated and unvaccinated groups were different in terms of age (p < 0.0481). Vaccination status against severe influenza was found to be an independent protective factor (OR = 0.840; 0.746-0.913).ConclusionsThe effectiveness of influenza vaccination provided greater protection against infection and reduced the severity of influenza in older hospitalized patients. These findings should be taken into account to improve vaccination strategies and achieve better vaccination coverage in the population at risk.  相似文献   

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Palynological assemblages are reported for the first time for the La Irene Formation, southwestern Santa Cruz Province, Argentina. This unit represents the sedimentation during a regressive period from transitional or delta-plain to fluvial environments. Palynological assemblages are scarce and moderately well preserved. They mainly consist of continental elements (wood remains, cuticles, spores and pollen grains) with scarse marine palynomorphs (dinoflagellate cysts). The spore-pollen assemblages are dominated by fern spores, followed by angiosperm and gymnosperm pollen grains. Bryophyte spores and fungal remains are also present. Among ferns, Cyatheaceae and spores of Laevigatosporites, of uncertain affinity, are dominant. Of the angiosperm pollen, those of Chloranthaceae (Clavatipollenites sp.) and Arecaceae (Arecipites spp., Longapertites sp., Spinizonocolpites hialinus Archangelsky and Zamaloa) are the most abundant. Pollen of Liliaceae (Liliacidites spp.), Proteaceae (Proteacidites sp., Peninsulapollis gillii (Cookson) Dettmann and Jarzen, Retidiporites camachoii Archangelsky) and Ericaceae (Ericipites scabratus Harris) are also present. Gymnosperm pollen is represented by Podocarpaceae (Podocarpidites spp.) and Ephedraceae (Equisetosporites sp.). These palynological suites would represent a fern-angiosperm dominated coastal vegetation, developed under warm and at least locally humid climatic conditions. La Irene Formation is considered Maastrichtian in age based on stratigraphic evidence, which is, in turn consistent with the ages suggested by the species ranges and the similarities observed with others previously described assemblages. This is the southernmost record of Spinizonocolpites, similar to the extant mangrove palm Nypa.  相似文献   

15.
Nerves of Locusta to the labrum, mandible, and hypopharynx were cut. Each of these operations deprived the whole organ of sensory nerves without affecting motor function. In other experiments palps, antennae, and galeae were removed. Feeding behaviour is measured by weighing faeces produced. This behaviour is not affected for long by suppressing a considerable number of sensory sensillae and it would appear that feeding is not dependent simply upon sensory areas in the regions studied.  相似文献   

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The protein family known as synucleins is composed of α-, β- and γ-synuclein. The most widely studied is the α-synuclein protein due to its participation in essential processes of the central nervous system. Neurotoxicity of this protein is related to the presence of multiplications (duplications and triplications) and point mutations in the gene sequence of the α-synuclein gene (SNCA), differential expression of its isoforms and variations in post-transductional modifications. Neurotoxicity is also related to cytoplasmic inclusions known as Lewy bodies (LBs) and Lewy neurites (LNs), which are also present in α-synucleinopathies. In general, the β-synuclein protein, codified by the SNCB gene, acts as a regulator of processes triggered by α-synuclein and its function is altered by variations in the gene sequence, while γ-synuclein, codified by the SNCG gene, seems to play a major role in certain tumoral processes.  相似文献   

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A systematic study of Lycopodium s.l. shows that only flavones occur in the four genera Huperzia, Lepidotis, Lycopodium s.s. and Diphasium. The arrangement of these taxa is discussed on the basis of the distribution of tricin, selgin, chrysoeriol, luteolin and apigenin. The evolutionary significance of these results and the uniqueness of Lycopodium phenolic metabolism are outlined.  相似文献   

18.
BackgroundThe high relative humidity and temperatures in tropical countries create favorable conditions for development of fungi that are not only a risk to human health but they can also colonize documentary support.AimsTo study the concentration of the airborne fungi in two repositories of the National Archives of the Republic of Cuba, the mycobiota deposited on different photographic supports and maps preserved in these repositories, and to determine the taxonomic characterization of the fungi isolated.MethodsThe air sampling was performed using a sedimentation method, and the supports (6 pictures and 7 maps) were analyzed using moistened sterile swabs.ResultsThe Cladosporium genus was predominant, followed by Aspergillus and Penicillium genera. Filamentous fungi were isolated in all the photos and maps, and yeasts were only isolated from a photographic supports and a map. We identified several species of Aspergillus and Penicillium genera, but Aspergillus niger and Aspergillus flavus predominated. Candida and Rhodotorula were the yeast genera isolated.ConclusionsThe fungal concentration of the air demonstrated that the environments were not contaminated. From the 26 species of filamentous fungi isolated only 5 were detected in the indoor air of the repositories and on one or more of the document supports analyzed (representing a 19.3%). This shows that there is a low ecological relationship between the fungi detected in the indoor air and those that were isolated from the supports studied.  相似文献   

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More than fifty ostracod species, twenty-two of which are Entomozoacea, have been identified in the upper part of the Teferguenite Formation and in the Marhouma Formation. The zonal sequence established on the Entomozoacea is applicable to the Frasnian and the Famennian of the Algerian Sahara; seven zones are recognized. One new species, Tubulibairdia marhoumaensis nov. sp., is described.  相似文献   

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IntroductionThe aim of our study was to evaluate the performances of pulmonary perfusion single photon emission computed tomography-computed tomography (SPECT-CT) with semi-automatic analysis for preoperative assessment for lung cancer.Materiel and methodThirty-five patients underwent preoperative lung perfusion scintigraphy (planar and SPECT-CT acquisition) from august 2016 to December 2017. Predicted postoperative forced expiratory volume in one second (ppoFEV1 and FEV1) by both methods were compared between each other and with the actual FEV1 measured 3 months after surgery. We also evaluated interobserver reproductibility of SPECT-CT semi-automatic segmentation software and the concordance of the data simulating reductions of 30 and 50% of acquisition time.ResultsFor 30 lobectomies and 5 pneumonectomies, the mean ppoFEV1 was 69%, a difference with actual ppoFEV1 of ?8% for SPECT-CT and ?6.77% for planar (P < 0,001). Both methods were well correlated, correlation coefficient was 0,827, 95% CI [0.686–0.909] but underestimated the actual poppFEV1. For SPECT-CT, interobserver reproducibility was excellent for pulmonary and lobar evaluation. The lobar functions, without 30 and 50% of the time acquisition, had absolute difference < 3% in comparison to native data.DiscussionWe did not prove SPECT-CT superiority on planar scintigraphy, actual FEV1 being difficult to predict because of confounding factors. But this exam could be useful before lobectomy and in cases of heterogeneous perfusion. Easily made, this method is reproducible even on data simulating a reduction of 50% of time acquisition.  相似文献   

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