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1.
Cladistic analysis of the subfamilies within the Tubificidae (Oligochaeta)   总被引:2,自引:0,他引:2  
A hypothesis of phylogenetic relationships within the family Tubificidae is presented, based on a Wagner analysis of morphological characters in the different subfamilies. Two major lincages are recognized. One, including the subfamilies Tubificinae, Telmatodrilinae and Limnodriloidinae, is supported by a synapomorphic ability to form slender spermatozeugmata in the spermathecae; the other, including Rhyacodrilinae (paraphyletic), Phallodrilinae, and the (present family) Naididae, is supported by two synapomorphics, the possession of modified penial setae and numerous coelomocytes (the latter secondarily lost in the Phallodrilinae). Some implications for the classification of the Tubificidae are discussed.  相似文献   
2.
Ataxia with vitamin E deficiency (AVED) is an autosomal recessive disease characterized clinically by neurological symptoms with often striking resemblance to those of Friedreich ataxia. This disorder has been reported previously as familial isolated vitamin E deficiency. We have mapped recently the AVED locus to a 5-cM confidence interval on chromosome 8q by homozygosity mapping in six Mediterranean families. We have now analyzed six new and two previously described families and demonstrate genetic homogeneity despite important clinical variability and wide geographic origins. Analysis of nine new tightly linked microsatellite markers, including four characterized in this study, revealed a predominant but not unique mutation in northern African populations, where this condition is more frequent. Haplotype analysis but also classical recombinations allowed us to refine the AVED position to a 1-cM interval. A YAC contig over this interval was constructed from marker STSs and YAC fingerprint data, in order to facilitate the search of the AVED gene.  相似文献   
3.
A taxonomic and morphological account of a collection of Phallodrilinae from coralline sands at Heron Island in Australia's Great Barrier Reef is given. Ten new forms are described: Jamiesoniella athecata gen. et sp.n. Phallodrilus rectisetosus heronensis subsp.n. P. geniculatus sp.n. P. filithecatus sp.n. P. clavatus sp.n. (latter three all devoid of an alimentary canal), Bathydrilus superiovasatus sp.n. Coralliodrilus atriobifidus sp.n. C. oviatriatus sp.n. C. parvigenitalis sp.n. and the gutless C. avisceralis sp.n. Morphological notes are given for Phallodrilus albidus Jamieson, 1977 and Bathydrilus rohdei (Jamieson, 1977). The new meiobenthic genus Jamiesoniella is characterized by having simple atria with only one pair of prostate glands, which are attached to ectal parts of atria, and by lacking spermathecae and penial setae, The genus is probably related to Aktedrilus Knöllner and Bacescuella Hrabě. A gutless species, Phallodrilus comorensis sp.n. is described from the Comoro Islands in the Mozambique Channel (W Indian Ocean).  相似文献   
4.
A quaternary amine, Aliquat 336, inhibits the growth of the green alga Chlorella emersonii, 14C-fixation of the alga is also inhibited. The effect and the site of action of the compound was studied by using isolated spinach chloroplasts. The carbon dioxide dependent oxygen evolution of the chloroplasts is inhibited directly upon the addition of the amine and the oxygen evolution is replaced by an oxygen uptake. By investigating some electron transport reactions in the chloroplasts we were able to show that Aliquat 336 affects the electron transport on the level of photophosphorylation. The results from the in vivo and the in vitro experiments thus show that the quaternary amine affects the photosynthetic process. Aliquat 336 is a solvent extractant used in several industrial processes for extraction of metals from aqueous solutions. Aliquat 336 could be considered a presumptive water pollutant as the compound could enter a recipient water body and thus affect photosynthesis.  相似文献   
5.
The taxonomy and morphology of Aktedrilus Knöllner, 1935 and Bacescuella Hrabe' 1973 (subfamily Phallodrilinae), both common genera of the marine, littoral meiofauna, were studied on the basis of material from various geographical areas. A. monospermathecus Knöllner, 1935 is redescribed from France and Scotland. A. magnus sp.n., A. hrevis sp.n., A. curvipenis sp.n. and A. floridensis sp.n. are described from Italy, Brazil, France and Florida, respectively. Two very closely related forms are described from the Pacific: A. locyi sp.n. (California) and A. parviprostatus sp.n. (Great Barrier Reef). B. mediterranea sp.n. is described from Italy, and new European records are given forB. arclica Erséus, 1978 andfi. parvithecata Erséus, 1978. Both genera are characterized by having two pairs of prostate glands, well developed penes, and unpaired, mid-dorsal spermatheca (if present). The species of Bacescuella transfer their sperm by means of external spermatophores, structures that are not developed in Aktedrilus. The eight species of Aktedrilus are largely distinguished by means of the morphology of the spermatheca, penes and prostates. The four species of Bacescuella differ principally from each other in the length of the vasa deferentia, and in the morphology of the prostates and copulatory organs. Most Bacescuella species lack spermatheca.  相似文献   
6.
This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-α were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-α were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-α and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.  相似文献   
7.
The present paper describes the development and validation of a simple and sensitive micelle‐enhanced high‐throughput fluorometric method for the determination of niclosamide (NIC) in 96‐microwell plates. The proposed method is based on the reduction of the nitro group of niclosamide to an amino group using Zn/HCl to give a highly fluorescent derivative that was developed simultaneously and measured at λem 444 nm after excitation at λex 275 nm. Tween‐80 and carboxymethylcellulose (CMC) have been used as fluorescence enhancers and greatly enhanced the fluorescence by factors of 100–150%. The different experimental conditions affecting the fluorescence reaction were carefully investigated and optimized. The proposed method showed good linearity (r2≥ 0.9997) over the concentration ranges of 1–5 and 0.5–5 μg/ml with lower detection limits of 0.01 and 0.008 μg/ml and lower quantification limits of 0.04 and 0.03 μg/ml on using Tween‐80 and or CMC, respectively. The developed high‐throughput method was successfully applied for the determination of niclosamide in both tablets and spiked plasma. The capability of the method for measuring microvolume samples made it convenient for handling a very large number of samples simultaneously. In addition, it is considered an environmentally friendly method with lower consumption of chemicals and solvents.  相似文献   
8.
A simple and eco-friendly hydrothermal technique is used to prepare water soluble N- and S-co-doped carbon quantum dots probes (N,S-CQDs) from thiosemicarbazide and citric acid. Several characterization techniques were performed to ensure the successful synthesis of highly luminescent N,S-CQDs. The prepared probe exhibited analytical potential as an optical nanosensor for the spectrofluorimetric determination of cromolyn sodium (CRO) in its pharmaceutical dosage forms and aqueous humour. The emission intensity of the synthesized N,S-CQDs was measured at 411 nm after excitation at 345 nm. Addition of increasing concentrations of CRO to N,S-CQDs led to quenching of its fluorescence intensity. CRO was investigated within a wide concentration range 10.0–150.0 μM with a limit of detection of 2.0 μM and a limit of quantification of 6.0 μM. The quenching of fluorescent N,S-CQDs occurred through the inner filter effect (IFE). The developed spectrofluorimetric method was successfully optimized and validated according to the International Council of Harmonisation guidelines (ICH). The method greenness is proved through using both Eco-Scale and AGREE approaches.  相似文献   
9.
10.
Melanoma differentiation-associated gene-7/interleukin-24 (mda-7/IL-24), a unique member of the IL-10 gene family, displays a broad range of antitumor properties including cancer-specific induction of apoptosis, inhibition of tumor angiogenesis, and modulation of anti-tumor immune responses. Here, we identify clusterin (CLU) as a MDA-7/IL-24 interacting protein in DU-145 cells and investigate the role of MDA-7/IL-24 in regulating CLU expression and mediating the antitumor properties of mda-7/IL-24 in prostate cancer. Ad.mda-7 decreased expression of soluble CLU (sCLU) and increased expression of nuclear CLU (nCLU). In the initial phase of Ad.mda-7 infection sCLU expression increased and CLU interacted with MDA-7/IL-24 producing a cytoprotective effect. Infection of stable clones of DU-145 prostate cancer cells expressing sCLU with Ad.mda-7 resulted in generation of nCLU that correlated with decreased cell viability and increased apoptosis. In the presence of mda-7/IL-24, sCLU-DU-145 cells displayed G(2)/M phase arrest followed by apoptosis. Similarly, Ad.mda-7 infection decreased cell migration by altering cytoskeleton in sCLU-DU-145 cells. Ad.mda-7-treated sCLU-DU-145 cells displayed a significant reduction in tumor growth in mouse xenograft models and reduced angiogenesis when compared to the vector control group. Tumor tissue lysates demonstrated enhanced nCLU generated from sCLU with increased apoptosis in the presence of MDA-7/IL-24. Our findings reveal novel aspects relative to the role of sCLU/nCLU in regulating the anticancer properties of MDA-7/IL-24 that may be exploited for developing enhanced therapies for prostate cancer.  相似文献   
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