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1.
In this work, incorporation of plasmid DNA, pre-complexed with PEI, into polyelectrolyte multilayers has been studied to further develop platforms for local gene delivery. Polyplex embedding in synthetic and naturally degradable architectures was efficient for transfection of human hepato-cellular carcinoma cells.  相似文献   
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The gene of Cytotoxic T Lymphocyte-associated Antigen 4 (CTLA4), a negative regulator of T lymphocytes, contains a single-nucleotide polymorphism (SNP) at position +6230A->G (ct60A->G), which has been found associated with several autoimmune diseases and appears to reduce T-cell inhibitory activity. In Ghana, West Africa, we compared the frequencies of CTLA4 +6230 A/G and 6 haplotype-tagging SNPs in 2010 smear-positive, HIV-negative patients with pulmonary tuberculosis (TB) and 2346 controls matched for age, gender and ethnicity. We found no difference in allele frequencies between cases and controls. However, +6230A and a distinct CTLA4 haplotype and a diplotype comprising the +6230A allele were significantly less frequent among cases with large opacities in chest radiographs compared to those with small ones (Pcorrected [cor] = 0.002, Pcor = 0.00045, P = 0.0005, respectively). This finding suggests that an increased T-cell activity associated with the CTLA4 +6230G allele contributes to pathology rather than to protection in pulmonary TB.  相似文献   
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A total dosage up to 1 mg PGF2a as i.v. infusions of 10–40 μg/min. was investigated on patients with arrhythmias of several kinds. We found therapeutic effects in 5 of 6 patients with constant extrasystoles and in one patient with digitalis - induced partial AV-block respectively. In 3 of 4 patients with acute tachyarrhythmias the results were not convincing, probably due to a dosage not high enough. An increase of the diastolic stimulation threshold usually seen with other antiarrhythmics was not to be observed in 3 patients. The mechanism of action of PGF2a has not yet been clarified.  相似文献   
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With enzyme histochemical methods, the distribution and the activities of various oxidative and hydrolytic enzymes in the apocrine glands of the general body surface of the domestic cat were investigated. The results obtained support the view that these glands are clearly active in function. On the whole, however, the relatively weak enzyme activities in the secretory portion of the glands point to only unimportant secretion production rates.  相似文献   
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The amino acid sequences of two isozymes of catechol oxidase from sweet potatoes (Ipomoea batatas) were determined by Edman degradation of BrCN cleavage fragments of the native protein and by sequencing of amplified cDNA fragments. Sequence alignment and phylogenetic analysis of plant catechol oxidases revealed about 80% equidistance between the two I. batatas catechol oxidases and approximately 40--60% to catechol oxidases of other plants. When H(2)O(2) was applied as substrate the 39 kDa isozyme, but not the 40 kDa isozyme, showed catalase-like activity. The structure of the 40 kDa isozyme was modeled on the basis of the published crystal structure of the 39 kDa isozyme [T. Klabunde et al., Nat. Struct. Biol. 5 (1998) 1084]. The active site model closely resembled that of the 39 kDa isozyme determined by crystallography, except for a mutation of Thr243 (40 kDa isozyme) to Ile241 (39 kDa isozyme) close to the dimetal center. This residue difference affects the orientation of the Glu238/236 residue, which is thought to be responsible for the catalase-like activity of the 39 kDa isozyme for which a catalytic mechanism is proposed.  相似文献   
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Several isolated marattialean synangia and sporangia are reported from coal balls collected from Coal Seam No.1 (C605) in the uppermost Permian Wangjiazhai Formation in Guizhou Province, south-western China. The synangia are radially symmetrical with diameters between 0.8 and 1.2 mm and are 1.7 mm long, consisting of 3–4 elongate sporangia that are fused basally, free distally and possess a pointed apex. The outer-facing sporangial wall is 4–5 cells thick and conspicuously differentiated. Spores are trilete, have a granular ornamentation and are nearly round equatorially with a diameter of 55–60 µm. Comparisons with other anatomically preserved Palaeozoic marattialean synangia from the Euramerican and Cathaysian floras permit their assignment to the genus of Scolecopteris (Zenker) Millay. In this species the thick, outer-facing sporangial walls and large trilete spores are features consistent with those of the Oliveri Group within Scolecopteris , a group that has previously been considered primitive within this genus. Distinctions from all other previously recognized species within the Oliveri Group lead to the creation of a new species, S. guizhouensis sp. nov. This species is the youngest of the reported species of Scolecopteris recognized from the Euramerican and Cathaysian floras, and provides important evidence on the organization of marattialean ferns from the Upper Permian strata of south China.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 279–288.  相似文献   
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