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排序方式: 共有10000条查询结果,搜索用时 281 毫秒
941.
942.
S Higashiyama M Horikawa K Yamada N Ichino N Nakano T Nakagawa J Miyagawa N Matsushita T Nagatsu N Taniguchi H Ishiguro 《Canadian Metallurgical Quarterly》1997,122(3):675-680
The availability of an analgesic compound devoid of the side effects associated with the commonly used opioid and nonsteroidal antiinflammatory drugs would be useful during the perioperative period. Although adenosine has analgesic and anesthetic-sparing properties, it also produces dose-dependent cardiovascular depression. Inhibitors of adenosine kinase may be able to provide analgesia without producing acute cardiovascular or respiratory depression. This preliminary study investigated the effects of a novel adenosine kinase-inhibiting drug, GP683, on the minimum alveolar anesthetic concentration (MAC) of desflurane in dogs. Seven mongrel dogs were administered one of three different GP683 dose regimens (or the solvent) by intravenous infusion on separate occasions according to a cross-over study design. After determining the baseline desflurane MAC value, GP683 was infused at 75, 150, or 300 microg x kg(-1) x min(-1) for 5 min as a loading dose, followed by 15, 30, or 60 microg x kg(-1) x min(-1) for an additional 85 min to maintain a stable plasma drug level. The desflurane MAC was redetermined 30-90 min after starting the study drug or vehicle infusion, and 30-90 min and 120-180 min after termination of the infusion. Cardiovascular variables and plasma concentrations of GP683 were determined at specific intervals before, during, and after the MAC determinations. The three GP683 dose regimens produced 22%, 31%, and 50% decreases in the desflurane MAC, respectively. In addition, there was good correlation between the decrease in desflurane MAC and the plasma GP683 concentration (r = -0.78). Although the mean arterial pressure (MAP) was decreased up to 25% by the highest infusion rate of GP683, adjustments in the desflurane concentration to an equi-MAC value resulted in normalization of the MAP values. Furthermore, GP683 produced no changes in heart rate. In conclusion, the adenosine kinase-inhibiting drug, GP683, produced dose-dependent decreases in the desflurane MAC of dogs without producing untoward hemodynamic changes. IMPLICATIONS: An investigational drug (GP683) that can increase the levels of an important endogenous substance in the body (adenosine) has been found to decrease the anesthetic requirement in dogs without producing adverse effects on the cardiovascular system. 相似文献
943.
Wakabayashi R. Kawakami H. Sato G. Amano T. Suzuki Y. 《Vehicular Technology, IEEE Transactions on》1998,47(2):392-405
A VHF omnidirectional radio range (VOR) is a navigation aid radio beacon facility, which provides aircraft with azimuth information relative to the VOR station in question as the origin. In Japan, two types of VOR-the conventional type (referred to as a CVOR) and the Doppler type (referred to as a DVOR)-are currently in use. An element known as the Alford loop antenna (ALA), which changes the loading reactance, is used for the VOR because the horizontally polarized wave and nondirectivity in the horizontal plane are preferred. A VOR antenna consists of a carrier antenna and a sideband antenna-an aircraft receives separate signals from these two antennas and compares them to obtain azimuth information. The mutual coupling between the elements forming the carrier and the sideband antenna affects the directivity of the single elements, resulting in errors in azimuth information. With the mutual coupling between the antenna elements being taken into consideration, a quantitative calculation was made by using the moment method-the results of the calculation made it clear that a loading reactance value of -320 Ω is better to make not mutually coupled elements nondirectional while a loading reactance value of -600 Ω is optimum to minimize the azimuth error of a CVOR 相似文献
944.
D. Dietrich ÖVE H. Reiter Th. Sauter H. -J. Schweinzer 《e & i Elektrotechnik und Informationstechnik》1997,114(5):225-230
The past decade may be regarded as the phase of the fundamental developments in fieldbus systems that were based on the OSI model. Today we are entering a second stage. It is the objective of this issue to present the current state and where the further developments will lead to. This introductory article is intended to give an overview on the subject. 相似文献
945.
The mechanical, electrical and thermal properties of alkaline earth metal (Mg, Ca and Sr)-doped LaCrO3 have been examined as separators in planar-type high-temperature solid oxide fuel cells. The maximum three-point bending
strength at 1000°C in air was measured and found to be 186 MPa for LaCr0.9Mg0.1O3, 36 MPa for La0.9Ca0.1CrO3 and 77 MPa for La0.9Sr0.1CrO3. The La0.8Sr0.2CrO3 separator placed in both an oxidizing and a reducing environment at 1000°C showed almost the same electrical conductivities
of the H2 atmosphere, and the conductivity was independent of sample thickness in the range 0.5–3.0 mm. For all the doped LaCrO3 perovskites, a difference between the thermal expansion behaviours of air and the H2 atmosphere was observed. In particular, the thermal expansion slope for the first heating cycle under the H2 atmosphere showed a marked change. The volume changes were due to the formation of oxygen defects in the perovskite structure.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
946.
H Uchino 《Canadian Metallurgical Quarterly》1997,44(7):499-508
For better understanding of the sexual behaviours that are high-risk in terms of HIV infection, a random sample of 200 people aged above 20 and below 60 years, from a population of 23,700, was selected in the provincial city of Nagano and surveyed by visitation. The responses of 156 people (a rate of response of 78%) were collected and the results were statistically analyzed. The methods employed in conducting a survey on sexual behaviour were also evaluated. The number of sexual partners is an indicator of high-risk sexual behaviour for HIV infection. The data reveals that 65.3% of the men and 37% of the women had two or more partners in the past, with 37.5% of the men and 12.5% of the women having two or more partners in the last 5 years, and 19.1% of the men and 4.2% of the women having two or more partners in the last year, revealing that a higher percentage of men than women have multiple partners. Comparison by age group reveals that young men and women in their 20s have the highest percentage of multiple partners. For both men and women first sexual intercourse before the age of 18, for men self-employment, being a craftsmen or in agriculture, and for women, higher education, were all factors in having greater numbers of partners. In conducting a survey on sexual behaviour the following should be kept in mind. 1) The psychological background of the respondent; Sex counseling skills are required on the part of the interviewer when taking a survey on sex since it is a very private and personal topic for people. Respondents have a tendency to be those who are open-minded about sex and are active in life, and these factors can exaggerate the survey results. 2) Conduct of a survey on sexual behaviour; The survey should be taken only after the purpose of the survey has been fully explained to the respondents and trust has been established. In principle, therefore, mailing of a letter of request and the actual questions should not be the method utilized prior to the collection of responses. 相似文献
947.
948.
A theoretical model is presented by which a true expression of pregnancy rate resulting from stimulated cycles can be calculated. This includes the transfer of both fresh and cryopreserved embryos. It is concluded that the total reproductive potential of a single cycle of stimulation can only be evaluated by including pregnancies arising from all fresh and frozen embryo transfers resulting from that cycle. 相似文献
949.
950.
BACKGROUND/PURPOSE: Recent reports have identified abnormal innervation of the circular muscle layer involving the fine intramuscular nerve fibers in hypertrophic pyloric stenous (HPS). HPS presenting after 3 months of age is rare. The aim of this study was to determine the distribution pattern of nerve fibers in the smooth muscle layers in HPS and correlate this with age at presentation. METHODS: Full-thickness pyloric muscle biopsy specimens were obtained from eight patients with HPS (five age 3 to 5 weeks, two age 3 months, and one age 7 months) and five controls with normal pylorus (age 5 days to 3 years). All specimens were stained with monoclonal antibody to the neural cell adhesion molecule (NCAM) using immunohistochemistry. RESULTS: There were many NCAM-positive nerve fibers in the circular and longitudinal muscle layers in the controls. No NCAM positive nerve fibers were seen in the circular or longitudinal muscle layers in the five cases of HPS in which the patients were less than 5 weeks old. In the two cases in which the patients were 3 months old, occasional NCAM-positive nerve fibers were seen in the circular layer, and moderate numbers of NCAM positive fibers were seen in the longitudinal muscle layers. Moderate numbers of NCAM-positive nerve fibers in the circular muscle layer and many NCAM positive nerve fibers in the longitudinal muscle layers were identified in the 7-month-old HPS patient. CONCLUSIONS: The data suggest that the pyloric muscle lacks innervation in the young HPS infant. Whereas, at 3 months of age the hypertrophied pyloric muscle is partially innervated, and at 7 months of age the pyloric muscle has practically normal innervation. 相似文献