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91.
The argon laser, which has been proven both useful and safe for port-wine stain therapy, interacts with the hemoglobin of the vessels. In a percentage of cases, this treatment is still inefficient, and there is a lack of correlation between these bad results and clinical or histologic criteria. Thermography, which explores the vascularization of the port-wine stain, leads us to consider port-wine stains from a physical point of view. This very simple test shows no correlation with the clinical parameters of port-wine stain but is closely related to the results obtained with laser therapy. It seems to be a good criterion to estimate the argon laser treatment prognosis.  相似文献   
92.
A restriction enzyme map of the IncFI plasmid ColV2-K94 was generated using EcoRI, BamHI, HindIII, and XhoI; the genetic features of this element were then mapped from previous heteroduplex studies.  相似文献   
93.
V Gerke  K Weber 《The EMBO journal》1985,4(11):2917-2920
The major cytoplasmic target of various tyrosine-specific protein kinases is a 36-kd protein (p36). This protein can exist as a monomer or as a complex with a small subunit which seems to have a regulatory function. Amino acid sequence analysis of the small subunit from porcine intestine documents a unique polypeptide of 95 residues with a calculated mol. wt. close to 11 kd (p11). Since an immunologically related subunit of the same electrophoretic mobility is also found in the corresponding complex of chicken intestine p11 is well conserved across species. Unexpectedly, the sequence of p11 shows a high homology with the glia-specific protein S-100 whose biological function is not known. Although both proteins are dimers of rather small polypeptides we have not been able to detect in our preparations of p11 the moderate Ca2+ binding known for S-100. Certain implications of this sequence relation are discussed.  相似文献   
94.
Guinea pigs and athymic nude (RNU/RNU) rats were used to assess the efficacy of three orally administered antifungal agents — Tolciclate, Tolnaftate, and Ketoconazole — against Trichophyton mentagrophytes dermatophytosis. All three antifungal agents inhibited the test strain of T. mentagrophytes in vitro. Antifungal agents were tested in intervention (oral therapy started 5 days after challenge) or prophylaxis (oral therapy started 5 days before challenge) protocols. Oral treatment of dermatophytosis on guinea pig skin demonstrated that Tolciclate and Tolnaftate alleviated clinical symptoms and shortened the duration of the dermatophytosis, in comparison to nontreated controls. Assessment of antifungal efficacy in the guinea pig model was time consuming (30–35 days) and variability in the duration and severity of clinical symptoms on guinea pig skin was common.Oral therapy of chronically infected athymic rats demonstrated that Tolciclate, Tolnaftate, and Ketoconazole were effective antifungal agents in vivo. Obvious improvement in clinical symptoms of dermatophytosis (i.e. less erythema and fewer lesions) was evident with all three antifungal agents within 10 days of starting oral therapy. By day 20, athymic rats that were treated with either Tolciclate or Ketoconazole showed marked clinical improvement of the chronic dermatophytosis.Chronically infected athymic rats, which lack thymus matured T-cells, are a promising new model to evaluate the efficacy of antifungal agents by culture, histology, and visual observations of clinical symptoms.  相似文献   
95.
96.
The oligosaccharide products resulting from treatment of mucin-type glycoproteins with alkali in the presence of the sulfite anion have been investigated. Treatment of fetuin and of tryptic glycopeptides from the human erythrocyte with this reagent resulted in the release of sulfited oligosaccharides identified as N-acetylsulfohexosamine (HexNAcSO3), alpha-NeuAc-(2----6)-HexNAcSO3, and alpha-NeuAc-(2----3)-Gal-(1----3 or 4)-[GlcNAc-(1----6)]-HexNAcSO3. In addition, 2.7 moles of sialic acid were released per mole of alpha-NeuAc-(2----6)-HexNAcSO3 from fetuin. The sulfohexosamine moiety is formed via unsaturated intermediates from a 3-O-substituted 2-acetamido-2-deoxy-D-galactosyl residue at the carbohydrate-peptide linkage site when this residue is not substituted at O-4 by another sugar residue. A reaction mechanism accounting for the release of the sulfited oligosaccharides from a 3-O- and 6-O-substituted hexosamine is proposed in which the oligosaccharide branch attached to O-6 is obtained as a specific fragment terminating in sulfohexosamine.  相似文献   
97.
Tiazofurin, a C-nucleoside, was cytotoxic in hepatoma 3924A cells grown in culture with an LC50 = 7.5 microM. In the culture, a closely linked dose-related response of tumor cell-kill and depletion of GTP pools was observed after tiazofurin treatment. In rats carrying subcutaneously transplanted hepatoma 3924A solid tumors, a single intraperitoneal injection of tiazofurin (200 mg/kg) caused a rapid inhibition of IMP dehydrogenase (EC 1.2.1.14) activity and depleted GDP, GTP, and dGTP pools in the tumor; concurrently, the 5-phosphoribosyl 1-pyrophosphate (PRPP) and IMP pools expanded 8- and 15-fold, respectively. Tiazofurin decreased tumoral IMP dehydrogenase activity and dGTP pools in a dose-dependent manner over a range of 50-200 mg/kg; by contrast, the depletion of GTP and the accumulation of IMP and PRPP pools were near maximum at 50 mg/kg. The increase in PRPP pools may be attributed to an inhibition by IMP of the activity of hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8). The IMP dehydrogenase activity and the pools of ribonucleotides returned to the normal range by 24-48 h after the single injection of tiazofurin. However, the markedly depleted dGTP pools remained low for 72 h. Tiazofurin treatment resulted in significant anti-tumor activity in rats inoculated with hepatoma 3924A. The decrease in GTP levels and particularly the sustained depletion in the dGTP pools may explain, in part at least, the chemo-therapeutic action of tiazofurin on hepatoma 3924A. This is the first report showing that a marked therapeutic response was achieved against rapidly growing hepatoma 3924A by treatment with a single anti-metabolite.  相似文献   
98.
A glycoprotein (s-GP III) was isolated from the soluble lysate of chromaffin granules by chromatography with immunoaffinity and lectin columns. An identical protein (m-GP III) was shown to be present in the granule membranes. The apparent molecular weight of these glycoproteins as determined by the electrophoresis system of Laemmli (1970) was 43,000 under reducing conditions. In the absence of mercaptoethanol they aggregated to dimers. Antisera were raised against both the soluble and the membrane-bound forms of this glycoprotein. With these antisera GP III was further characterized: Immunoreplicas were obtained after two-dimensional electrophoresis of soluble and membrane-bound proteins of chromaffin granules. GP III was identified as a protein with a rather broad pI (4.6-5.3), indicating microheterogeneity. As shown by subcellular fractionation, m-GP III is specifically confined to chromaffin granules. GP III can therefore be used as a marker for the membranes of these organelles. The soluble form is secreted from adrenal medulla during stimulation with carbamylcholine chloride. An immunologically identical antigen was detected in adeno- and neurohypophysis. The physiological function of GP III is still unknown. It does not demonstrate any of the enzymatic activities so far known to occur in chromaffin granules.  相似文献   
99.
Studies were designed to investigate whether the cellular immunodeficiency state observed in human glioblastoma patients could be due to inhibitory factors released by the tumor cells. Cultured human glioblastoma cells were found to secrete an interleukin 1-like factor (m.w. 22,000) and a factor (m.w. 97,000) that inhibits interleukin 2 (IL 2)-dependent T cell mechanisms. This is demonstrated by its inhibitory effect on the IL 2-induced proliferation of T cell clones and on the induction of alloreactive cytotoxic T cells in mixed lymphocyte cultures. Additionally the glioblastoma cell-derived 97,000-m.w. factor inhibited growth of neuroblasts but not of fibroblasts and thus shares the characteristics of the neuroblast growth inhibition factor (NGIF) previously detected in the supernatant of fetal rat glia cell cultures. If released by glioblastoma cells in vivo, the factor may contribute to impaired immunosurveillance and to the cellular immunodeficiency state detected in the patients.  相似文献   
100.
In a 24 h kinetic study docosahexaenoic acid (DCHA, C22:6n-3) or eicosapentaenoic acid (EPA, C20:5n-3) were given in a single dose to healthy male volunteers. PGI3-M, the main urinary metabolite of prostaglandin I3 was below the detection limit in the control periods, but was excreted already in the first 4 h after ingestion of DCHA or EPA and decreased thereafter. Excretion of PGI2-M did not change significantly. In a second dietary trial DCHA and EPA were given cross-over to 7 healthy male volunteers for 6 days. PGI3-M was formed after DCHA and EPA in amounts of 35 and 20 % of PGI2-M and showed a considerable interindividual variation. The structure of PGI3-M was verified by independant biochemical synthesis. Our data indicate that dietary DCHA is retroconverted to EPA in man, which is quickly transformed - like dietary EPA itself - to prostaglandin I3. DCHA may therefore serve as a precursor fatty acid for EPA and its cyclooxygenated and lipoxygenated products.  相似文献   
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