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81.
Rallinyssus sorae sp. n. is described from the nasal turbinates of the sora, Porzana carolina, collected in Maryland and Ohio. The new species is most similar to Rallinyssus verheyeni Fain but differs in number of setae on the female ventral opisthosoma, structure of the fixed and movable digits of the male and female chelicerae, chaetotaxy of legs I to IV, and presence of a sternal plate in the male. The taxonomy and host-parasite relationships of the various species of Rallinyssus are discussed. 相似文献
82.
A survey was carried out of doctors who used their out-of-hours biochemistry service to find out why requests for investigations were made, how often the results altered patient management, and whether they could define areas where investigations were unproductive. Of 107 questionnaires distributed, 147 (88%) were completed. In 86% the requests were for diagnosis or immediate patient management and in 35% the results actually altered management. Senior clinical staff were more efficient than their juniors in instigating biochemical investigations that proved to be effective. In no instance where the clinical staff predicted that it was unlikely that the results would alter management was management altered. It is suggested that joint reviews of case notes by junior and senior clinical staff would prove to be the most appropriate way to increase the effectiveness and efficiency of clinical investigation. 相似文献
83.
By using inhibitors of elongation factor Tu (L-1-tosylamido-2-phenylethyl chloromethyl ketone [TPCK] and kirromycin), we determined the effect of elongation factor Tu inhibition on the synthesis of individual components of the translation machinery. The rates of synthesis of individual proteins were measured in double-label experiments using a two-dimensional gel system. TPCK inhibition produce a coordinate decrease in the differential synthesis rates of all components of the translation machinery examined in these experiments. On the other hand, kirromycin inhibition increased the differential synthesis rates of some translation components and decreased the differential synthesis rates of others. These results suggest that the metabolic regulation of synthesis of various translation proteins is not mediated through a common signal. 相似文献
84.
An anaerobic population of bacteria became acclimated to catechol and phenol in 32 and 18 days, respectively. Evidence from carbon balance measurements indicates that the aromatic ring is cleaved and that the products are stoichiometrically fermentable to methane and carbon dioxide. 相似文献
85.
Prostaglandin F2α levels were measured by radioimmunoassay in 95 samples of unextracted human cerebrospinal fluid obtained from 73 patients with advanced cancer. Concentrations okf PGE were too low to be reliably determined by this method using the commercially available kits. Forty-six of the samples assayed contained <25pg/ml PGF2α. The remaining levels ranged from 25 to 1154 pg/ml c.s.f.; the majority contained less than 200pg/ml. A possible correlation was found between elevated c.s.f. granulocyte count and increased PGF2α. A similar relationship was found with regard to protein. These studies failed to demonstrate a correlation between elevated levels of PGF2α in cerebrospinal fluid and any pathophysiologic condition. 相似文献
86.
The binding of Hg(II) to poly(dA-dT) has been examined with proton NMR spectroscopy. Addition of HgCl2 between r (Hg2+/nucleotide) = 0 and 0.25 results in loss of the exchangeable imino N3H resonance of thymine, indicating preferential binding at this site. The nonexchangeable base resonances AH8, AH2, and TH6 shift their intensity downfield in a cooperative manner, indicating complexation which is slow on the NMR time scale and changes in the polymer conformation upon binding. At r = 0.25, the polymer is cross-linked, and an increase in temperature does not result in denaturation of the polymer, as evidenced by the thymine proton resonance chemical shifts. The chemical shifts of the AH2 and T(CH3)5 base resonances allow some general conclusions to be made about the stereochemistry of this complex. 相似文献
87.
Hans Holtschmidt Konrad Sandhoff Werner Fürst Hae Young Kwon Doris Schnabel Kunihiko Suzuki 《FEBS letters》1991,280(2):267-270
The organization of 14 exons covering 97% of the cDNA sequence of human cerebroside sulfate activator protein precursor has been determined from two overlapping EMBL-4 human genomic clones extending over 17kb. All exons and exon/intron splice junctions and five introns were sequenced. Exon 8 consists of only 9 bp and is involved in alternative splicing which generates three different mRNAs of cerebroside sulfate activator precursor. 相似文献
88.
Leslie D. Manley Ronald Kuczenski David S. Segal Stephen J. Young Philip M. Groves 《Journal of neurochemistry》1992,58(4):1491-1498
In vivo microdialysis was employed to detect changes in extracellular dopamine and serotonin in the rat caudate in response to electrical stimulation of the medial forebrain bundle. Extracellular dopamine concentrations increased linearly as a function of the frequency (4-33 Hz) of evenly spaced stimuli in both the presence and absence of cocaine added to the dialysate. Because dopamine neurons are known to fire in single-spike and burst patterns, stimulation pulses were also delivered in a bursting pattern. The response of extracellular dopamine was augmented in both the presence and absence of cocaine when the same number of stimuli were delivered in bursts as compared to an evenly spaced pattern. Serotonin, which was only assessed in the presence of cocaine, similarly increased linearly with frequency, but, in contrast to the dopamine response, levels of serotonin were not augmented by stimuli presented in bursts. These results suggest that microdialysis can be used to detect physiological changes in synaptic transmitter concentrations. 相似文献
89.
The mouse 3T3-L1 fibroblastic cell line rapidly differentiates to an adipocyte phenotype when post-confluent cells are treated for 48 h in fetal calf serum-containing medium supplemented with 1 microM dexamethasone (D), 0.5 mM methylisobutylxanthine (M) and 10 micrograms/ml insulin (I). D and I act synergistically to commit the cells to differentiate 24-48 h after initiating treatment, and this is blocked by the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate. In order to identify cellular proteins involved in the differentiation process we analyzed differentiating 3T3-L1 cells using two-dimensional electrophoresis on large format gels. We observed changes in over 300 proteins during differentiation (over 100 within 5 h of initiating differentiation) and many of these are also changed at the level of mRNA (by analysis of in vitro translation products). About 75% of the initial changes were maximally induced by treatment with a combination of M and I, while no more than 10 proteins and their corresponding mRNAs were maximally induced by D within 3.5 h. Another 10 proteins were synergistically regulated by the combination of all three agents (DMI) within 3.5 h. Additional species were induced at later times. Five of these were synergistically induced by treatments that lead to differentiation, were first expressed at elevated levels during commitment and remained elevated in fully differentiated adipocytes. One or more of these proteins could well have a functional role in the commitment to and/or expression of the adipocyte differentiation program. 相似文献
90.
R H Schuster R R Kuske V L Young B Fineberg 《Plastic and reconstructive surgery》1992,90(3):445-52; discussion 453-4
The records of 55 patients who had breast cancer treated by mastectomy, irradiation, and breast reconstruction were reviewed for cosmetic outcome, complications, and tumor control. Median follow-up was 35 months. Local control rates were 95 percent in patients treated for high risk factors or breast conservation and 85 percent in patients treated for recurrent breast cancer. Acceptable cosmetic results were obtained in only 42 percent of patients. The incidence of complications was 55 percent. Transverse rectus abdominis muscle (TRAM) reconstructions gave superior cosmetic results compared with all other types of reconstructions. The timing of reconstruction in relation to mastectomy or radiation therapy did not significantly influence cosmetic outcome, although other factors suggest that delayed reconstruction may give better results. A majority of patients were satisfied with cosmetic outcome. 相似文献