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81.
82.
Receptors for estrogens and progesterone have been assayed in 24 samples of normal human endometria at different phases of the menstrual cycle. In the proliferative endometrium the concentration of estrogen binding sites was significantly higher than that of progesterone receptor while, in the secretive endometrium, the concentration of estrogen receptor was low, compared to that of progesterone receptor. The highest concentration of both receptors was observed during the periovulatory period. From the correlation observed between estrogen and progesterone receptors and the levels of the respective steroids in the plasma, it is suggested that the levels of plasma estradiol or its own tissue receptor determine the synthesis of progesterone receptors in the periovulatory period.  相似文献   
83.
Effect of Cerulenin on Growth and Lipid Metabolism of Mycoplasmas   总被引:1,自引:0,他引:1       下载免费PDF全文
Cerulenin markedly inhibited the growth of Acholeplasma laidlawii. A. axanthum and A. granularum were less susceptible, whereas the sterol-requiring Mycoplasma species examined showed very little susceptibility. The inhibition was not reversed by the addition of long-chain fatty acids to the medium. At a concentration of 20 mug/ml, cerulenin inhibited the incorporation of [(14)C]acetate into A. laidlawii membrane lipids, but it had no effect on either protein or nucleic acid biosynthesis. Cerulenin inhibited both the de novo synthesis of long-chain fatty acids and the elongation of medium-chain fatty acids. As a result, carotenoid biosynthesis was stimulated, and increased amounts of oleic and elaidic acids were incorporated into membrane polar lipids. Our studies support the concept that cerulenin can serve as a useful tool for obtaining better control of fatty acid composition of A. laidlawii membranes.  相似文献   
84.
DNA chromosomic sequences from Ureaplasma urealyticum were shown, by DNA hybridization, to possess homology with Providencia stuartii urease genes. The homologous ureaplasma DNA fragment was cloned in Escherichia coli and a DNA probe, designated IC61 probe was specific for only the urease-producing U. urealyticum among the Mollicutes. Genetic homology shown between the IC61 probe and urease genes from Campylobacter pylori, E. coli and P. stuartii suggests that (1) the cloned DNA fragment from U. urealyticum contains urease encoding sequences, and that (2) the urease genes possess conserved sequences among phylogenetically distant prokaryotes.  相似文献   
85.
86.
Lipoglycans (previously designated lipopolysaccharides) from several species of Acholeplasma and from Thermoplasma acidophilum were examined for endotoxin-like activities as measured by the standard rabbit fever test and the Limulus amoebocyte lysate assay. The lipoglycans from Acholeplasma granularum, Achloplasma laidlawii, Acholeplasma modicum, and Acholeplasma oculi caused a febrile response at concentrations of 1 ng/ml per kg or greater, whereas with control Escherichia coli EC-2 lipopolysaccharides, 6.25 ng/ml per kg was required. Similar results were obtained in the Limulus amoebocyte lysate test. The minimum concentrations in nanograms per milliliter required to stimulate formation of a solid clot were: Acholeplasma axanthum, 0.22; A. granularum, 0.85; A. modicum, 0.51; A. laidlawii, 1.05; A. oculi, 0.74. Standard E. coli 1B lipopolysaccharide required a concentration of 0.125 ng/ml. Thermoplasma lipoglycan was least active, requiring 4.25 ng/ml. Clotting of the Limulus lysate proceeds by the activation by lipopolysaccharide plus Ca2+ of a proenzyme which cleaves an arginine-lysine peptide bond of the coagulogen. The clotting and amidase activities are inactivated by deoxycholate and can be reactivated by addition of lipopolysaccharide and Ca2+. As with E. coli 1B lipopolysaccharide, acholeplasmal lipoglycans were shown to restore both clotting and amidase activities of the deoxycholate-inactivated Limulus clotting enzyme. The degree of restoration of amidase activity by mycoplasmal lipoglycans relative to E. coli lipopolysaccharide (1.00) were: A. axanthum, 1.71; A. modicum, 1.22; A. granularum, 0.61; and Thermoplasma, 0.37. The coagulating enzyme, restored with either E. coli lipopolysaccharide or mycoplasmal lipoglycans, was able to react with the synthetic peptide benzoyl-Ile-Glu-(γ-OCH3)-Gly-p-nitroaniline (an analog of the coagulogen) or with the purified coagulogen itself to form the clot. The mycoplasmal lipoglycans alone were incapable of promoting these reactions when incubated with the synthetic peptide or with the purified coagulogen, thereby ruling out the contamination of these lipoglycans with proteases capable of cleaving the same Arg-Lys peptide bond of the coagulogen. These results show that acholeplasmal lipoglycans possess endotoxin-like activities. Their passive or active role in disease remains to be established.  相似文献   
87.
A hamster immunization challenge assay described in the accompanying paper (M. F. Barile, D. K. F. Chandler, H. Yoshida, M. W. Grabowski, R. Harasawa, and S. Razin, Infect. Immun. 56:2443-2449, 1988) was used to examine protection against Mycoplasma pneumoniae disease by passive immunization and to evaluate the protective potency of a Formalin-inactivated whole-cell and a cell extract M. pneumoniae vaccine. Passive immunization with a globulin fraction of hyperimmune mule antiserum to M. pneumoniae provided hamsters some protection against the challenge. When hamsters were actively immunized, a single dose of Formalin-inactivated vaccine provided only minimal protection, whereas multiple doses of this vaccine, particularly when combined with adjuvant, provided good protection. A single dose of the cell extract vaccine did not protect animals, but two doses caused a marked reduction of disease when a priming dose was given intraperitoneally, followed by a booster dose intratracheally. The correlation between the level of metabolism inhibition antibodies to M. pneumoniae in the sera of vaccinated hamsters and the degree of protection as measured by reduction of lung pathological scores and colonization was poor, indicating that seroconversion rates for metabolism inhibition antibodies are not by themselves adequate to measure the potency of M. pneumoniae vaccines.  相似文献   
88.
The authors describe percutaneous treatment of gallbladder or bile duct stones in 18 patients who were poor surgical candidates or in whom conventional therapy failed. Dissolution was performed in most cases with methyl tert-butyl ether (MTBE) because of its potent dissolution properties; other solvents used included monooctanoin or chelating solutions. Gallbladder stones were eliminated in 11 of 13 patients (six of seven with dissolution alone, four of four with dissolution and basket extraction, one with basket removal alone). In five patients with stones in the common bile duct (n = 3), cystic duct remnant (n = 1), and intrahepatic bile ducts (n = 1), stones were eliminated with dissolution alone in two and with dissolution plus basket extraction in one. In two patients percutaneous therapy failed due to complications (vagal hypotension with bile peritonitis and transient respiratory arrest) that occurred during catheter placement. Preliminary results suggest that MTBE is effective for dissolution of many gallbladder stones and some bile duct stones. Noncholesterol solvents and adjuvant mechanical maneuvers are valuable adjuncts to achieve complete stone elimination.  相似文献   
89.
The haemodynamic premises for extra-anatomical by-pass in the treatment of stenosis and obstructions of the subclavian and vertebral arteries are discussed with a report on a surgically treated series.  相似文献   
90.
McCall  IW; Moule  N; Desai  P; Serjeant  GR 《Radiology》1978,126(1):99-104
A prospective study of the renal abnormalities on excretion urography in 189 patients with homozygous sickle cell disease is presented. Demonstrable abnormalities were present in 69% but there was no correlation with symptomatology. Calyceal clubbing was the most common abnormality occurring in 39% of cases and its incidence increased with age. An unexpectedly high prevalence (23%) of papillary necrosis occurred and both sinuses and cavities were demonstrated. The reasons for this high prevalence are discussed. The urographic findings did not correlate significantly with hematological features of the disease.  相似文献   
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