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951.
The safety profile, tolerability, pharmacodynamics, and pharmacokinetics of four doses of recombinant human granulocyte colony-stimulating factor (filgrastim) were assessed in healthy volunteers in a double-masked, placebo-controlled, parallel-group trial. Healthy subjects received subcutaneous injections of filgrastim 75 microg (n = 8), 150 microg (n = 4), 300 microg (n = 4), 600 microg (n = 8), or placebo (n = 6) daily for 10 consecutive days. Blood samples were drawn daily immediately before the injection and on days 1 and 10 serially throughout the day. Increased absolute neutrophil counts (ANCs) were seen within 90 minutes of drug administration in subjects in all dose groups, peaking approximately 12 hours after administration. This increase was dose related in subjects in the three lower dose groups. The time to peak ANC on day 10 was approximately 9 hours, with a daily ANC profile in all four dose groups that was similar to the profile on day 1. In all dose groups, ANCs were near baseline within 48 hours of discontinuation of filgrastim. Mild, reversible thrombocytopenia was reported in 4 of 10 subjects in the highest dose group. Two subjects in the filgrastim 600-microg group were withdrawn for adverse events. Filgrastim had a good safety profile and caused dose-related increases in ANC when administered to healthy volunteers for up to 10 days.  相似文献   
952.
Influenza C was propagated by serial undiluted passage; conditions known to produce non-infectious (von Magnus) particles with influenza A and B. Following each passage infectious material was assayed for infectivity and haemagglutinating activity and the values related by calculating the log difference between infectivity and haemagglutinating titre (I:A ratio). Infectious material from each pass was examined for ultrastruct aberrations by negative strain electron microscopy. Influenza C exhibited a significantly smaller decrease in I:A ratio than exhibiyed by similarly propagated influenza A and B. Ultrastructural examination of the serially passed influenza C revealed no production of morphologically aberrant forms, whereas serially passed influenza B produced a strikingly altered morphology.  相似文献   
953.
954.
New compounds corresponding to the formula AnBnO3n+2 with n = 4,5; 5 and 6 have been found in the two following systems Nd2Ti2O7CaTiO3 and Ca2Nb2O7CaTiO3. These compounds have been investigated by electron microscopy. The results obtained are in good agreement with our structural hypothesis.  相似文献   
955.
Infants between 12 and 21 days of age can imitate both facial and manual gestures; this behavior cannot be explained in terms of either conditioning or innate releasing mechanisms. Such imitation implies that human neonates can equate their own unseen behaviors with gestures they see others perform.  相似文献   
956.
A patient acquired tickborne oculoglandular tularemia in early summer in rural Virginia. Tick exposure may be a clue to the diagnosis of tularemia in the eastern as well as the western United States, especially in summer months. A review of the experience with tularemia in Virginia for the last 13 years shows a bimodal seasonal incidence of tularemia with an associated vector exposure in 77.4% of 106 cases. The majority of cases occurring during winter months have been associated with rabbit exposure, while those in summer months are often associated with tick exposure.  相似文献   
957.
The neutral lipids of the skin from the feet of turkey poults fed a biotin supplemented or a biotin deficient diet consist mainly of triacyglycerols, and of mono- and diester waxes. Diester waxes from both groups were characterized as fatty acid esters of erythro-2,3-alkanediols. A comparison between fatty acid composition of the two groups, however, revealed the following significant differences. Biotin deficient birds showed a fairly high concentration of very long chain fatty acids (C36-C40) which were completely absent in biotin supplemented birds. Further, almost one-third of the fatty acids of diester waxes in biotin deficient birds were unsaturated while those from biotin supplemented birds were predominantly (96%) saturated.  相似文献   
958.
The hospital and autopsy records of 40 infants who died with perinatal telencephalic leucoencephalopathy (PTL) (hypertrophic astrocytes and amphophilic globules in telencephalic white matter) were compared to those of 76 control infants who had no white matter abnormality. A linear discromination procedure, which takes into account multiple confounding factors, was used to estimate risk ratios. PTL was found more commonly in infants who (a) had bacteria isolated from blood at autopsy, (b) received intravenous glucose and water for more than one day, or (c) received kanamycin or streptomycin. Infants were at reduced risk if they received penicillin, atropine, mercurhydrin or a transfusion of whole blood. It is hypothesized that endotoxin from bacteremia adversely affects developing white matter and that the other risk factors of PTL are markers of, or contributors to, increased risk of gram negative infection. No evidence was found for antibiotic-endotoxin interaction. The factors that are associated with reduced risk of PTL may be markers of, or contributors to reduced risk of gram negative infection.  相似文献   
959.
The electromagnetic behaviour of an open resonator with spherical mirrors is analysed. Usual approximate theories are insufficient, excepted for the very large radius of curvature. Electromagnetic theory for any curvature of the mirrors and multi-dielectric cavities is studied.  相似文献   
960.
Expanding, adult-length catheters to accommodate continuing somatic growth have been implanted in the course of shunts, either to the heart or peritoneum, in 12 hydrocephalic infants and young children. Three of four patients with direct cardiac shunts are doing well 22, 28 and 30 months following primary shunt operations, and five of eight patients with ventriculo-peritoneal shunts are progressing favourably four to 10 months after shunt placement. While no claims can be made for long-term benefits, the preliminary results of these procedures are encouraging.  相似文献   
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