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1.
A restriction map of chicken embryo lethal orphan (CELO) virus DNA was reported with ten restriction endonucleases (XbaI, XhoI, SalI, HindIII, EcoRI, BglI, KpnI, BamHI, PstI and SstI). CELO virus DNA was estimated by comparing CELO virus DNA fragments with marker DNA fragments to have a molecular weight of 29.3·106.  相似文献   
2.
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects.  相似文献   
3.
A human rotavirus AU228 strain which resembled the AU-1 strain (O. Nakagomi, T. Nakagomi, Y. Hoshino, J. Flores, and A. Z. Kapikian, J. Clin. Microbiol. 25:1159-1164, 1987) in its novel characteristics (that it belonged to subgroup I yet possessed a long RNA pattern) was compared with various human and animal strains by RNA-RNA hybridization in solution. This strain showed a high degree of homology with the AU-1 strain but not with either the Wa (subgroup II, long pattern) or the KUN (subgroup I, short pattern) strain, indicating the presence of an additional group of human rotaviruses that do not belong to either of the two human rotavirus families previously identified by RNA-RNA hybridization. It is of particular interest that the AU228 strain showed an unexpectedly high degree of homology with a feline rotavirus isolated recently in Japan. These results indicate transmission of a feline rotavirus to humans and suggest a role of animal rotaviruses in the evolution of human rotaviruses.  相似文献   
4.
Acetylthrombin, succinylthrombin, maleylthrombin, polyethylene glycol (PEG)-thrombin, and acetylated PEG-thrombin were prepared and characterized. Although clotting activities could be reduced remarkably by the modification, the potencies of all the modified thrombins for protein C activation also decreased. However, in the case of acetylthrombin, succinylthrombin, and acetylated PEG-thrombin, the remaining potencies for protein C activation exceeded largely the remaining clotting activities. Moreover, by the addition of thrombodulin, the potencies for protein C activation were enhanced 16 - 60 fold for succinylthrombin, maleylthrombin, and PEG-thrombin.  相似文献   
5.
6.
We have identified a new mutation of Norrie disease (ND) gene in two Japanese males from unrelated families; they showed typical ocular features of ND but no mental retardation or hearing impairment. A mutation was found in both patients at the initation codon of exon 2 of the ND gene (ATG to GTG), with otherwise normal nucleotide sequences. Their mothers had the normal and mutant types of the gene, which was expected for heterozygotes of the disease. The mutation of the initiation codon would cause the failure of ND gene expression or a defect in translation thereby truncating the amino terminus of ND protein. In view of the rarity and marked heterogeneity of mutations in the ND gene, the present apparently unrelated Japanese families who have lived in the same area for over two centuries presumably share the origin of the mutation.  相似文献   
7.
In this paper, we report the effect of pectic substances and D-galacturonic acid, the main constituent of pectic substances, on activated hyaluronidase and histamine release from mast cells. Although D-galacturonic acid itself showed no inhibition, IC50 values of hyaluronidase inhibition were correlated with the D-galacturonic-acid content of pectic substances. It was thought that the polymerization of D-galacturonic acid was necessary for inhibition of activated hyaluronidase. This type of inhibition was suggested to be non-competitive by the Lineweaver-Burk plot. Furthermore, pectic substances, including those purified from Gymnema sylvestre, inhibited histamine release from isolated rat peritoneal mast cells, which had been induced by the antigen. These results suggest that pectic substances may have anti-allergic activities.  相似文献   
8.
The absorption spectra and circular dichroism (CD) have been measured for aqueous solutions of acridine orange of a constant concentration, [D] = 5 × 10?5M, mixed with poly(S-carboxyethyl-L -cysteine) in various mixing ratios, [P]/[D], ranging from 330 to 11, at different pH. The absorption spectra of the dye–polymer solutions are hypochromic, and the main band is located at 470 nm, accompanying a shoulder at 500 nm. At alkaline pH, no CD is induced in the visible region. At neutral and acidic pH, where the polymer is in the β-conformation, CD is induced in the visible and near-uv regions. A pair of CD bands is located at the region around 450 nm, when the pH is around the neutrality, while it appears at the region around 500 nm at acidic pH. Thus, the optically active species of bound dye changes from dimer to monomer on lowering the pH. These species form dissymmetric arrays along a polypeptide chain. The fraction of bound dye forming dissymmetric sequences is not high, but most of bound dye is adsorbed randomly on the ionized carboxyl groups of polypeptide chain and gives rise to hypochromism only. A dissymmetric structure of dye–polymer complexes is presented, in which the polymer has the β-conformation and the dye cations, either dimeric or monomeric, bind to its side chains, in such a way that the longer axes of molecular planes of bound dye form a two-fold, right-handed helix along the extended polypeptide chain. A zeroth-order calculation of CD based on the coupled oscillator model leads to the result that each dissymmetric array of dye consists, on the average, of two dimeric or monomeric cations. This low number of bound cations in a dissymmetric array and the large fraction of randomly adsorbed dye suggest that the hydrophobic interaction of dye with the polymer is strong, so that dye cations are adsorbed sparsely on both sides of the extended polypeptide chain.  相似文献   
9.
Genetic mutations in the purine salvage enzyme, hypoxanthine-guanine phosphoribosyltransferase (HPRT), are known to cause Lesch–Nyhan syndrome and Kelley–Seegmiller syndrome. In patients, purine metabolism is different from that of normal persons. We have previously developed a method for simultaneously determining the concentration of purine and pyrimidine nucleosides and nucleotides. This system was applied to determine the concentrations of nucleosides and nucleotides in HPRT-deficient cell lines. The amount of inosine 5′-monophosphate (IMP) was different in Lesch–Nyhan syndrome, Kelley–Seegmiller syndrome, and control cell lines. The difference in the amount of IMP confirmed the mutation of the enzyme.  相似文献   
10.
Human papillomavirus (HPV), particularly HPV16, is strongly associated with premalignant lesions of the uterine cervix and cervical cancer. However, HPV infection is a common sexually transmitted disease and only a few women develop cervical cancer. Although the presence of HPV and abnormal cytology are independent risk factors for cervical diseases, implementing both tests on every woman is argued not to be recommended mainly in terms of cost-effectiveness. During a 20-month period between October, 1994, and May, 1996, cervical swabs from 207 women who were referred for colposcopy because of cervical dyskaryosis (Papanicolaou class IIIa or higher) were examined by PCR for the presence of HPV16. When these women were divided into two groups; i.e., group A consisting of women who were 44 years old or younger (n = 111), and group B consisting of women who were 45 years old or older (n = 96), the risk of having premalignant and malignant cervical diseases upon infection with HPV16 was approximately 8 times higher in group A than in group B. Thus, we conclude that HPV-testing should be implemented on every young woman with an abnormal Papanicolaou smear test.  相似文献   
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