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111.
A coupling constant-dihedral angle correlation for the H? Cα? Cβ? H system of amino acid residues in peptides has been derived from a set of model compounds covering the full range of dihedral angles. The expression obtained, J = 11.0 cos2 θ ?1.4 cos θ + 1.6 sin2θ, is close to those already used in pmr studies of peptide conformation, and provides a firmer foundation for them. A factor limiting the precision of this and other “Karplus relations” is illustrated.  相似文献   
112.
Analogues of d-glucose modified at C-3, and in some cases at a second position, were prepared and tested for active accumulation by everted segments of hamster intestine. Their relative affinity for the sugar carrier was measured by tissue/medium ratio, Michaelis-Menten kinetics and competitive inhibition of d-galactose or methyl alpha-d-glucoside transport. d-Glucose and its 3-deoxy-3-fluoro, 3-chloro-3-deoxy and to a smaller extent its 3-bromo-3-deoxy derivatives, bound and were transported more strongly than 3-deoxy-d-glucose and other sugars not containing an electronegative atom in the gluco configuration at C-3. 3-Deoxy-d-galactose, 3,6-dideoxy-d-glucose and d-gulose, which have two alterations from the d-glucose structure, were not, or only very weakly, transported. The results are interpreted as indicating the presence of a hydrogen bond from the carrier to the hydroxyl group at C-3 of d-glucose. Spatial requirements are also discussed. New syntheses are reported for 3-chloro-3-deoxy- and 3-bromo-3-deoxy-d-glucose and 3,6-dideoxy-d-glucose.  相似文献   
113.
The effect of several controlled variables on the peak titer and fold increase of Rift Valley fever virus grown in suspension culture on two variants of Earle's L cell, L-DR and L-MA clone 1-1, was studied. No significant amount of cell-associated virus was found at 24 hr, indicating a release of virus soon after its formation. Mild sonic treatment of the virus produced in serum-free medium increased the infective titer about 10x. This difference was not observed with virus produced in medium supplemented with serum. Peak titer was not affected by medium used during the infection period, by multiplicity of inoculum (MOI), or by initial cell concentration within the test range of 10(4) to 2 x 10(6) cell/ml. Cell strain employed influenced titer, because the L-DR cell did not produce virus efficiently at low MOI and low initial cell concentration. The time of peak titer and fold replication was dependent on MOI and initial cell concentration. Differences in virus propagation in monolayer and suspension systems are discussed.  相似文献   
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115.
Secondary fermentation of sweet wine was prevented by the Delle stabilization procedure. For this procedure, advantage is taken of the inhibitory effects of high concentrations of sugar as well as of alcohol. Thus, relatively small amounts of wine spirits were added to fermenting musts to obtain stability, as compared to the conventional procedure in which larger amounts of alcohol are added and the inhibitory effect of alcohol only is considered. The Delle value is a function of the concentrations in the wine, after spirits addition, of alcohol and sugar. Delle values which gave stable wine were dependent on time of alcohol addition, on strain of wine yeast, and on composition of wine spirits. Fractional addition of spirits, concentration of SO(2), and clarity of must had little effect on the Delle value. Sensory comparison of wines especially prepared for tasting by the Delle procedure and by the conventional procedure showed the wines made by the Delle procedure to be superior in quality. Under proper storage conditions, the Delle wines were shown to be microbiologically stable and resistant to wine spoilage organisms.  相似文献   
116.
Zusammenfassung Bei einem normal intelligenten, kleinwüchsigen, 219/12 jährigen Mann mit Hypospadie, fraglicher rudimentärer Vagina und hypergonadotropem Hypogonadismus findet man bei der Biopsie des nur 7 ml großen linken Hodens eine gleichförmige tubuläre Atrophie mit Fehlen des Keimepithels und eine diffuse, kleinherdige Leydigzellwucherung. Sex-Chromatin in den Leydigzellen, im Mundabstrich und Drumsticks negativ. Karyotyp in den Lymphocyten und im Knochenmark normal weiblich (46,XX), in den Fibroblasten jedoch 45,XO.Somit weist dieser Patient Testesgewebe auf, das Y-Chromosom ist aber unauffindbar. Zur Klärung dieser Diskrepanz scheint das Vorhandensein einer dritten, zahlenmäßig stark in den Hintergrund tretenden, ein Y enthaltenden Zellpopulation die naheliegendste Hypothese zu sein.Eine Zwillingsschwester kam im Neugeborenenalter ad exitum; die Blutgruppenuntersuchungen beim Patienten und seiner Familie machen aber einen Blutchimärismus sehr unwahrscheinlich.Das klinische Bild unseres Patienten ist vollkommen verschieden von demjenigen, das beim XX/XO-Mosaik üblicherweise beobachtet wird und läßt sich auch vom klassischen Klinefelter-Syndrom deutlich abgrenzen. Es zeigt Ähnlichkeiten mit einigen Fällen von XO/XY-Mosaik.
Summary In a normally intelligent man of 219/12 years the following main physical findings were present: short stature, hypospadias, possibly a rudimentary vagina, hypergonadotropic hypogonadism, small testis (7 ml) with tubular dystrophy consisting in absence of germinal epithelium and localized proliferation of Leydig's cells. Sex chromatin in buccal mucosa cells was negative; no drumsticks were found in neutrophils. The karyotype in lymphocyte cultures and bone-marrow preparations was 46,XX; in several independent fibroblast cultures 45,XO.The most likely explanation for the presence of testicular tissue seems to be the existence of an undiscovered cell population containing a Y-chromosome.A twin sister of the patient died in early infancy; blood group investigations gave no indications for the presence of blood chimerism.The clinical picture of this patient is entirely different from that of the usual XX/XO mosaics, it also clearly differs from Klinefelter's syndrome but shows some similarities to cases of XO/XY mosaicism.


Direktor: Prof. Chr. Hedinger  相似文献   
117.
118.
Rats, rabbits, swine, guinea pigs, and monkeys were infected with anthrax spores, and their temperature responses were recorded. These were characteristic for a species and appeared independent of resistance or susceptibility of the species toward establishment of the disease. The rabbit appeared unique in that it not only failed to demonstrate a dose-response relationship over an 8-log dose range, but acted independently producing erratic body temperatures depending on spore dose. This limits the usefulness of the rabbit in studying anthrax pathogenesis, and poses questions regarding published data with the rabbit as the test animal.  相似文献   
119.
Conditions were investigated for the production of a new gum by the yeast Cryptococcus laurentii var. flavescens NRRL Y-1401 in shaken flasks and 20-liter fermentors. The most suitable medium contained 6% commercial glucose, 0.25% autolyzed brewer's yeast, and 0.001% MnSO4 and had an initial pH of 6.5. Polysaccharide yields, as measured by the dry weight of the alcohol precipitates, were in the range of 30 to 35% based on initial glucose.  相似文献   
120.
Nineteen adults who had acute glomerulonephritis were reviewed with respect to the clinical course and long-term follow-up. The age range was from 17 to 55 years. Only one patient died during the acute episode. In 11 cases, onset occurred between November and January and 15 of the patients had a known respiratory tract infection three to 30 days before the onset. The most important symptoms noted were weight gain, edema, dyspnea, oliguria and red or smoky urine. The most prominent physical signs were elevated blood pressure, edema, abnormalities in the chest and fever of over 100° F. Fifteen patients showed roentgen evidence of pulmonary vascular congestion, pleural effusion, cardiomegaly, pneumonia or a combination of these abnormalities. All the patients had proteinuria and red blood cells in the urine, and half of them had red blood cell casts. Azotemia, when present, subsided in 9.4 days. The average diastolic pressure was 105 mm. of mercury and the mean fall was 26 mm. in 23.5 days. At six months, nine of the 13 patients still being observed continued to show proteinuria or microscopic hematuria (seven showed both). A late follow-up of ten patients showed one to have significant hypertension and one to have early functional impairment and inconstant proteinuria. In these cases the average blood pressure was 140/91 mm. as compared with 119/74 mm. at the time of discharge.Sporadic glomerulonephritis in adults presents essentially the same pattern as it does in children. Urinary abnormalities may persist for months or even years, and neither the present series nor those reported by others clearly reveal the ultimate prognosis.  相似文献   
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