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991.
AH Nielsen K. Schauser H. Winther V. Dantzer K. Poulsen 《Clinical and experimental pharmacology & physiology》1997,24(5):309-314
1. The aim of the present study was to characterize the angiotensin II (AngII) receptor subtypes in the porcine uterus and the variation of receptor densities and renin concentrations during gestation. 2. In myometrium from non-pregnant sows, the AngII receptors were almost exclusively AT2 receptors. During gestation, the AngII receptor density was decreased and the AT1 receptor became predominant in the last part of gestation as a result of a down-regulation of the AT2 receptor. 3. In the endometrium, the AT1 receptor was predominant both in non-pregnant sows and throughout gestation. The AngII receptor density was decreased during gestation as a consequence of down-regulation of the AT1 receptor. 4. The renin concentrations in the myometrium and endometrium of pregnant sows did not differ from those in non-pregnant animals. 5. The finding of enzymatically active renin and high densities of AngII receptors in the porcine uterus is in accordance with a functional renin-angiotensin system (RAS), which may be important for an increased vascular permeability and stimulated angiogenesis in early pregnancy and for contraction of the myo-metrial smooth muscle cells during parturition. The predominance of ATi receptors in the endometrium of non-pregnant sows differs from an earlier finding in non-pregnant women, where AT2 receptors were predominant in the endometrium. This is in accordance with earlier studies, indicating species differences in the expression and possibly also the physiological roles of the RAS in reproductive tissues. 相似文献
992.
Abstract: Previous studies suggested that the use of a baby-enrolment and reminder system for early childhood immunisation increased public immunisation clinic attendance. It was decided to run a trial to assess the effects of introducing a baby-enrolment program on attendances at local government immunisation clinics. Enrolment leaflets were distributed to each mother of a new child in six areas of greater Sydney while the mother was in the postnatal ward of the local hospital. Clinic attendance figures were monitored, interviews were conducted with mothers as well as professionals involved in early childhood health services, and the conduct of clinics was observed. The trial failed to increase attendance at public clinics. Mothers' reasons for choice of service, particularly their desire for what they believed to be a more personalised service, and the attitude of the professionals (particularly community nurses) with whom they came in contact were considered to be more influential in determining their use (or lack of use) of public immunisation services. Baby enrolment may be effective in increasing attendance at public immunisation clinics only where there is willing cooperation of all stakeholders in supporting public immunisation services. 相似文献
993.
P M Kemp A S Houston M A Macleod R J Pethybridge 《Journal of neurology, neurosurgery, and psychiatry》1995,59(4):368-374
The objective was to compare two neurophysiological variables in active amateur boxers with non-boxing sportsmen. 41 boxers and 27 controls were given psychometric tests: 34 boxers and 34 controls underwent technetium-99m hexamethylpropyleneamineoxime single photon emission computerised tomography (Tc-99m HMPAO SPECT) cerebral perfusion scans. The controls performed better at most aspects of the psychometric tests. Boxers who had fought fewer bouts had a tendency to perform better at psychometric tests than those boxers who had fought more bouts. Tc-99m HMPAO SPECT cerebral perfusion scanning showed that controls had less aberrations in cerebral perfusion than the boxers. In conclusion, significant differences were shown in two neurophysiological variables between young amateur sportsmen who box and those who do not. The long term effects of these findings remain unknown. 相似文献
994.
A. Haase A. Melder H. Smith-Vaughan D. Kemp B. Currie 《Epidemiology and infection》1995,115(1):115-121
Twenty-seven isolates of Burholderia pseudomallei (formerly Pseudomonas pseudomallei) from ten patients with recurrent melioidosis were analysed by RAPD. In two cases RAPD patterns in recurrent isolates differed from the original isolates; one was considered a likely reinfection while the other may represent relapse from one of two strains initially infecting the patient. In two cases where a change in antibiotic resistance had occurred between original and relapse isolates, slight changes in RAPD patterns were found with one of the four primers used. In the other six cases the relapse was clearly due to the original strain re-emerging unchanged, with identical RAPD patterns with all four primers. 相似文献
995.
Dental material artifacts on MR images 总被引:2,自引:0,他引:2
Hinshaw DB Jr; Holshouser BA; Engstrom HI; Tjan AH; Christiansen EL; Catelli WF 《Radiology》1988,166(3):777-779
Magnetic resonance (MR) imaging of the head and neck is becoming an important aid in evaluating pathologic conditions of the brain, midface, and pharynx. Certain dental materials cause artifacts during MR imaging of the lower midface. These artifacts can obscure the normal anatomy. This study describes the degree of artifact production caused by various materials commonly used in dental restorations. Of the materials tested, those causing artifacts were made of stainless steel, such as orthodontic bands used for braces, and pins or posts that are commonly drilled into teeth to provide structure or stability before filling. Materials used as temporary or permanent fillings or crowns--such as amalgam, gold alloy, aluminum, microfilled resin, and polyvinyl acrylics--did not cause artifacts in the images. 相似文献
996.
A prototype 5,000-word recognizer for the generation of radiologic reports by voice entry was evaluated. The system had a capacity sufficient enough to include all radiologic examinations and all desired words in one lexicon. The lack of such a capacity had been identified as a major limitation of a 1,000-word system previously evaluated. Overall reliability in word recognition was 98%. The device may be widely applicable for use in any radiology practice. 相似文献
997.
Smith TP; Hunter DW; Cragg AH; Darcy MD; Castaneda-Zuniga WR; Sinclair TR; Ercole C; Hulbert JC; Kaye KW; Amplatz K 《Radiology》1988,168(1):137-139
Spermatic venography with hot contrast material embolization was undertaken in 81 patients with varicoceles and infertility. Long-term follow-up information was available in 91% of the patients, and there was an overall conception rate of 40.5%. Embolization with hot contrast material was easily performed without special embolization devices and proved to be a safe and effective technique. 相似文献
998.
Phosphofructokinase in the rat nervous system: regional differences in activity and characteristics of axonal transport 总被引:2,自引:0,他引:2
The distribution of phosphofructokinase (PFK) in gray and white matter regions of the rat nervous system was evaluated. Determinations of PFK activity revealed that cell body enriched regions (sensorimotor cortex) had a significantly higher level of activity than axonal regions (sciatic nerve, dorsal roots, and optic nerve). The level of PFK activity was also significantly higher in central axons (optic nerve) than in peripheral axons (sciatic nerve). Differences in PFK activity could be largely attributed to differences in tissue content of the enzyme rather than to differences in the types of PFK isozymes present. Cortex contained significantly larger amounts of PFK relative to total protein than did peripheral nerve. However, purification of PFK revealed that all three of the PFK isozymes, C (86 kd), A (84 kd), and B (80 kd), were present in both cortex and sciatic nerve. Both SDS/PAGE and immunoblotting studies using PFK isozyme-specific antibodies demonstrated that the relative proportions of the three PFK isozymes were similar in cell body and axonal regions of the nervous system. The PFK-C and PFK-A isozymes each comprised about half the total and only small amounts of the PFK-B isozyme were present in both regions. However, immunoprecipitation experiments suggested that quantitatively different proportions of the possible PFK hybrids (tetramers) may be distributed between axonal and cell body regions. The transport of PFK was examined in this study and PFK was identified in slow component b (SCb) of axonal transport. SCb moves at a rate of 2-4 mm/day in rat axons and is known to contain several other enzymes of intermediary metabolism as well as actin. The finding that PFK, the rate limiting enzyme in glycolysis, is present in SCb lends support to the hypothesis that glycolytic enzymes are not freely diffusing proteins in axons but, instead, are present as organized assemblies that have long-term, yet flexible, associations with structural elements of the cytoplasm. 相似文献
999.
1000.
The hydrogenation of the series of methylene-interrupted cis,cis-octadecadienoic acids by pure cultures of six rumen bacteria 总被引:1,自引:0,他引:1
The hydrogenation of all the methylene-interrupted cis,cis-octadecadienoic acids was examined using pure cultures of six rumen bacteria able to hydrogenate linoleic acid to stearic acid or its immediate precursor, trans-11-octadecenoic acid, after first conjugating the linoleic acid to cis,trans-9,11-octadecadienoic acid. Only the delta 14-cis,17-cis-isomer was not hydrogenated by at least one of the bacteria and no evidence was found that conjugation was necessary before hydrogenation except for the delta 2-cis,5-cis- and delta 9-cis,12-cis-isomers. Several isomers were hydrogenated to an extent close to that achieved with linoleic acid (delta 9-cis,12-cis). Those bacteria only able to hydrogenate linoleic to trans-11-octadecenoic acid gave only octadecenoic acid products and those bacteria able to hydrogenate linoleic acid to stearic gave variable yields of octadecenoic acids and stearic acid except with the isomers delta 12-cis,15-cis and delta 13-cis,16-cis when only octadecenoic acids were detected. At the substrate levels used (20 micrograms/ml), both inhibition and stimulation of growth were found but no common pattern emerged, nor was the growth consistently related to the extent of hydrogenation. 相似文献