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331.
JE Myers T Mieczkowski J Perel D Abbondanza TB Cooper JJ Mann 《Canadian Metallurgical Quarterly》1994,35(2):112-120
Serotonergic responsivity was assessed in 20 psychiatric patients by the prolactin response to a fenfluramine challenge test. During the fenfluramine challenge 6 of 20 patients (30%) spontaneously reported psychopathologic reactions that included: increased anxiety/agitation, psychotic symptoms, illusions, mood elevation, and anergia. The time of peak behavioral symptoms (2.5 +/- 0.8 hrs) corresponded closely to the time of peak increase in prolactin levels (3.0 +/- 1.1 hr). Abnormal behavioral responders had statistically significant greater increases in prolactin 1 to 4 hr after fenfluramine when compared to normal responders. Patients who developed an abnormal psychopathologic response to fenfluramine were characterized by higher levels of anxiety and agitation at the time of admission to the hospital but otherwise were not distinguishable on the basis of severity of other psychiatric symptoms. This study suggests that increased serotonergic transmission may trigger anxiety, psychosis, and mood elevation in specific vulnerable individuals, whereas other patients with similar psychiatric illnesses are not affected. 相似文献
332.
We evaluated the effect of 4-(2-benzylphenoxy)-N-methylbutylamine hydrochloride (bifemelane hydrochloride) on superoxide production by human neutrophils using an MCLA-dependent chemiluminescence assay. Bifemelane hydrochloride dose-dependently inhibited superoxide production by neutrophils stimulated with phorbol myristate acetate, opsonized zymosan, or N-formyl-methionyl-leucyl-phenylalanine, while it had no effect on superoxide production by a hypoxanthine-xanthine oxidase system. These results indicate that bifemelane hydrochloride does not have a scavenging effect, but has an inhibitory effect on superoxide generation by neutrophils. Although this drug is commonly used for treating chronic cerebral infarction, it may also have a protective effect on acute ischemia/reperfusion injury. 相似文献
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334.
An electroimpact compaction method recently developed for powder consolidation is described In terms of the basic principles of electric discharge and dynamic compaction processes. The influence of processing parameters, microstructural characteristics and mechanical properties of preforms obtained are discussed. Mathematical models for the mechanics of compaction, electrical resistance, discharge current variations and comparisons with experimental results are presented. The best set of properties are obtained when electrical discharge is applied to cause interparticle fusion at the instant when dynamic compaction pressure attains its peak level. 相似文献
335.
Recently published studies indicate a potential clinical application of PET in head and neck tumors. In the preoperative staging phase, PET enables confirmation of regional lymph node extension and guides nodal neck dissection or systemic treatment. In this phase, a high negative predictive value, near 100%, could make it possible to avoid many negative neck dissections. This is a reliable technique for confirming or excluding the presence of recurrent/residual tumor and for obtaining an early evaluation of chemotherapeutic and radiotherapeutic response. PET imaging in many cases makes it possible to locate and guide histological study of tumors with an unknown primary. PET imaging for these indications is a perfect complementary method for clinical exploration and better than other imaging techniques. 相似文献
336.
Explicit analytic design rules are derived for both 3 dB and full adiabatic couplers. The design rules are in excellent agreement with numerical calculations using the beam propagation method (BPM). It is shown that the length scaling for 3 dB couplers compared to full couplers makes the former more difficult to design. The design for each case is optimized to obtain the upper limit of performance and a comparison is carried out between two different design geometries for both 3 dB and full adiabatic couplers 相似文献
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338.
The incidence of Campylobacter jejuni and Campylobacter coli in broiler farms was 33.9% (19/56). C. jejuni-positive flocks accounted for 20.0% (17/85) and C. coli-positive ones was 4.7% (4/85). There were 14 patterns (fla type) of restriction fragment length polymorphism (RFLP) of flagellin A gene among these 22 strains of C. jejuni and C. coli including the standard strain C. jejuni ATCC 33560. Different fla types of Campylobacter were isolated from broilers in different growing cycles on the same farms. Four strains of C. jejuni were isolated from four breeder farms and four fla types of C. jejuni were detected from their progenies reared on growing farms. Three fla types of C. jejuni detected from the progenies were different from those of each breeder. Also, the other three fla types of C. jejuni were detected from different progenies of each growing farm during the next growing cycle. These findings indicate that the RFLP analysis may contribute to epidemiological studies of C. jejuni and C. coli contamination of broilers and suggest the risk of contamination with different types of Campylobacter in every growing cycle of broilers on the farm even on the same farm. They also supported that there was little likeliness of the vertical transmission of C. jejuni and C. coli from breeders to broilers. 相似文献
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340.