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141.
During two years of passage, several myxamoebal strains of Physarum polycephalum changed with regard to their properties in crosses and plaque morphology. These changes have been correlated with increased nuclear deoxyribonucleic acid content.  相似文献   
142.
Selective esterification reactions of 1,6-anhydro-3-deoxy-β-D-xylo-hexopyranose(1), 1,6-anhydro-β-D-glucopyranose (7), and several derivatives of 7, were conducted with an acid chloride or acid anhydride in pyridine. Reaction of 1 with p-toluenesulfonyl chloride and with benzoyl chloride gave 70 and 63%, respectively, of the 2-esters. The 2-methyl and 2-benzyl ethers of 7, both having strongly hydrogen-bonded C-4 hydroxyl group, reacted with p-toluenesulfonyl chloride to yield the 4-monosulfonates (71 and 74%, respectively). Esterification of the 2-methyl ether and 2-p-toluenesulfonate of 7 with p-toluenesulfonic anhydride instead of with p-toluenesulfonyl chloride led to increased yields of the 4-p-toluenesulfonates after a shorter reaction-time.  相似文献   
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Serial passage of the 64-2389 strain of type 3 parainfluenza virus in cercopithecus monkey kidney tissue cultures at low temperatures resulted in the selection of a variant which had a higher efficiency of plaque formation at 25 C than the parent line grown at 37 C. The cold variant, unlike the parent strain, plaqued readily at 25 C, and at 37 C it produced significantly larger plaques. Virus titers of the cold variant in hamster lungs were significantly lower and this was probably caused by the stimulation of interferon by the cold variant during the early phase of the infection. The cold variant, like the virus grown at 37 C, also induced the synthesis of interferon late in the infection. Hamsters responded to the intranasal inoculation of each virus line by the development of hemagglutinating-inhibiting antibodies in the sera.  相似文献   
146.
A survey was made of the NaCl tolerance of approximately 1,300 Streptomyces strains belonging to 313 species. The growth medium of the organisms was supplemented with a graded series of NaCl concentrations (4, 7, 10, and 13%). Only 1.8% of the species could not tolerate 4% NaCl; 26.9% could grow at a maximum of 4%; 49.7% could tolerate a maximum of 7%; 18.8% could grow at a maximum of 10%; and only 2.8% could tolerate 13% NaCl. In evaluating the relationships of NaCl tolerance to various taxonomic features, higher tolerance was statistically associated with the "yellow" and possibly the "white"-spored streptomycetes, whereas the "red"-spored series tended to have lesser tolerance. Higher tolerance was also indicated for spiny-spored species, as a group, than for smooth-spored forms. Likewise, nonproducers of melanin, collectively, were more NaCl tolerant than melanin-producing species. Uniformity of test responses between strains of species studied suggested the usefulness of NaCl tolerance as a taxonomic criterion.  相似文献   
147.
Zusammenfassung Die Epithelzellen der Plexus chor. ventr. III und IV, das Paraphysenepithel und das Ventrikelependym von Rana temporaria L. zeigen eine deutliche — wenn auch quantitativ unterschiedliche — Aktivität von SDH, -HBDH und LDH. Der Nachweis einer UDPGGT-Aktivität fällt dagegen nur im Plexusepithel positiv aus. In der Plexusepithelzelle sind die Formazangranula gleichmäßig über das gesamte Plasma verteilt, während sie in den Ependymzellen vorwiegend im apikalen, lumenwärtigen Teil der Zelle angeordnet sind. Die Ependymzellen lassen im Reaktionsausfall Typenunterschiede erkennen. Bei einigen Tieren wird die Auswirkung einer Adrenalininjektion auf das Enzymmuster der Plexusepithelzellen untersucht; die funktionellen Zusammenhänge mit einer gleichzeitigen Entspeicherung ihres Glykogenvorrats werden erörtert. Die Verteilung und der Lamellierungstyp der Mitochondrien im Plexus- und Paraphysenepithel werden mit elektronenmikroskopischen Aufnahmen illustriert. Einige Komentare sind dem histochemischen Verhalten des Wundrandes gewidmet.
Histochemical studies on the choroid plexuses, the paraphysis cerebri, and the ependyma of Rana temporaria L.
Summary The epithelium of the choroid plexuses of the IIIrd and IVth ventricles as well as the paraphyseal epithelium and the ventricular ependyma cells of Rana temporaria L. show distinct activities of SDH, -HBDH and LDH, that differ quantitatively. The UDPGGT-reaction is positive in the plexus epithelium. In the epithelium of the choroid plexus, the formazan granules are evenly distributed in the cytoplasm. In the ependyma cells an apical accumulation of this material can be demonstrated. The various morphological types of the ependyma cells differ in the intensity of the SDH, -HBDH and LDH-reactions. In the plexus cells of some animals the effect of epinephrine was studied on the histochemically-detectable activity of these enzymes with respect to the simultaneous depletion of the glycogen depot. The distribution and ultrastructure of mitochondria is described in the choroid plexus and paraphyseal epithelial cells. A comment is made in reference to some histochemical pecularities of stab wound areas.


Teil einer medizinischen Doktorarbeit.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   
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Often patients in whom there is little to suggest myxedema or cretinism have subclinical hypothyroidism. Once the condition is suspected, it can be diagnosed by determination of protein-bound iodine and, if the PBI is low, by response to therapy with thyroid hormone.Patients in the following categories should have protein-bound iodine determination: Those having (1) a history of previous treatment for hypothyroidism; (2) suboptimal development in children; (3) ovarian dysfunction, infertility, habitual abortion or unusual menopausal disorders; (4) symptoms of malaise and debility, such as undue fatigue, somnolence, mental asthenia and anxiety; (5) unexplained anemia; (6) colloid goiter, adenomatous goiter and cancer of the thyroid gland.If hypothyroidism is diagnosed, administration of thyroid hormone in increasing amounts, as determined by serial serum PBI tests, should be carried out indefinitely. Instruction of the patient is essential.  相似文献   
150.
Although Montreal is in an endemic area, significant clinical histoplasmosis with systemic manifestations has been, until recently, infrequently diagnosed. However, since the autumn of 1963, 31 cases of clinically significant histoplasmosis have been seen by the authors. These were divided into two groups: (1) patients in whom the diagnosis was established on the basis of histological and/or cultural demonstration of the fungus; (2) patients in whom the diagnosis was based on a positive histoplasmin skin test, a complement fixation antibody titre of 1:32 or greater and compatible clinical and radiological findings. An additional group of 11 patients who presented with erythema multiforme was investigated and a heretofore unrecognized relationship between histoplasmosis and erythema multiforme was established.  相似文献   
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