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991.
Previous research suggests that corticotropin-releasing hormone can act in the locus coeruleus to increase the firing of locus coeruleus neurons and elicit physiological responses resembling those associated with stress. The present study used immunocytochemical detection of Fos as a measure of neuronal activation to identify brain areas that were activated by bilateral injections of corticotropin-releasing hormone into the locus coeruleus of rats. Injection of corticotropin-releasing hormone into the locus coeruleus increased the expression of Fos in the locus coeruleus as compared with injection of vehicle into the locus coeruleus or injection of corticotropin-releasing hormone into neighbouring pontine sites. The pattern of Fos expression throughout the brain after injections of corticotropin-releasing hormone into the locus coeruleus was generally consistent with the anatomical organization of efferent projections arising from the locus coeruleus; increased Fos expression was observed in many brain areas including the ventral lateral septum, septohypothalamic nucleus, bed nucleus of the stria terminalis, the central amygdaloid nucleus, the dorsomedial nuclei of the hypothalamus, and the thalamic paraventricular and rhomboid nuclei. Foot shock also increased Fos expression in the locus coeruleus and the other brain regions that expressed Fos after corticotropin-releasing hormone injections into the locus coeruleus. A few brain regions, most notably the hypothalamic paraventricular nucleus, expressed Fos in response to foot shock but not corticotropin-releasing hormone. These results indicate that local injection of corticotropin-releasing hormone into the locus coeruleus stimulates the activity of the locus coeruleus neurons. However, the pattern of Fos expression throughout the brain evoked by injection of corticotropin-releasing hormone into the locus coeruleus does not fully replicate the effects of foot shock. 相似文献
992.
DE Heinrichs JA Yethon PA Amor C Whitfield 《Canadian Metallurgical Quarterly》1998,273(45):29497-29505
The major core oligosaccharide biosynthesis operons from prototype Escherichia coli strains displaying R1 and R4 lipopolysaccharide core types were polymerase chain reaction-amplified and analyzed. Comparison of deduced products of the open reading frames between the two regions indicate that all but two share total similarities of 94% or greater. Core oligosaccharide structures resulting from nonpolar insertion mutations in each gene of the core OS biosynthesis operon in the R1 strain allowed assignment of all of the glycosyltransferase enzymes required for outer core assembly. The difference between the R1 and R4 core oligosaccharides results from the specificity of the WaaV protein (a beta1, 3-glucosyltransferase) in R1 and WaaX (a beta1, 4-galactosyltransferase) in R4. Complementation of the waaV mutant of the R1 prototype strain with the waaX gene of the R4 strain converted the core oligosaccharide from an R1- to an R4-type lipopolysaccharide core molecule. Aside from generating core oligosaccharide specificity, the unique beta-linked glucopyranosyl residue of the R1 core plays a crucial role in organization of the lipopolysaccharide. This residue provides a novel attachment site for lipid A-core-linked polysaccharides and distinguishes the R1-type LPS from existing models for enterobacterial lipopolysaccharides. 相似文献
993.
DR Jeyarajah TA Gonwa G Testa O Abbasoglu R Goldstein BS Husberg MF Levy GB Klintmalm 《Canadian Metallurgical Quarterly》1998,66(4):529-532
We conducted a double-blind, randomized, placebo-controlled study to investigate the effectiveness of P6 acupuncture on postoperative vomiting in children undergoing strabismus surgery. Acupuncture was performed by laser stimulation with a low-level laser. Laser stimulation of P6 was administered 15 min before induction of anaesthesia and 15 min after arriving in the recovery room. In the laser stimulation group, the incidence of vomiting was significantly lower (25%) than that in the placebo group (85%). 相似文献
994.
A 61-year-old women receiving warfarin after mitral valve replacement experienced extensive ecchymoses after starting tramadol therapy. Laboratory values revealed critical elevations of prothrombin time and international normalized ratio. The patient's coagulation values returned to acceptable levels after discontinuing tramadol and temporarily stopping warfarin. The mechanism for this interaction is unknown. Practitioners should be aware of the possibility of such a interaction and exercise caution when tramadol is prescribed for a patient receiving warfarin. 相似文献
995.
996.
A Schürholz S Opitz G Dietrich D Heinrichs R Füssle G Hempelmann 《Canadian Metallurgical Quarterly》1998,43(1-2):14-18
Electrodiagnostic techniques used in an EMG-Laboratory and the diagnostic value in focal mononeuropathies are presented. The electrodiagnostic techniques include nerve conduction studies and needle electrode examination. Measurement of distal latency, amplitude, conduction velocity and the finding of focal conduction block may localize the focal character of the mononeuropathy. The needle electrode examination gives further information about distribution, extent, activity, or chronicity of the disease, especially in cases with axonal injuries. Some normal electrodiagnostic patterns are presented, accompanied by some illustrative pathological cases. 相似文献
997.
One hundred seven freshman student athletes in 17 different women's and men's intercollegiate sports were required to attend evening study sessions. The student athletes completed academic assignments and studied for tests primarily in cooperative learning groups. As gauges of the program's impact on the participants, 3 questionnaires were administered to a sample of 50 (25 women and 25 men). The respondents reported that (a) they worked cooperatively on academic assignments, (b) the program staff provided both academic and personal support while structuring and facilitating cooperative learning groups, and (c) they themselves were highly task oriented, confident of their academic ability, and involved in positive and supportive relationships with their fellow participants. 相似文献
998.
Conceptuses from several mammalian species prior to implantation secrete proteins belonging to the family of interferons. The main species of interferons known to be secreted by the pig blastocyst is interferon gamma (IFNgamma), the precise role of which is unclear. We decided to explore its effects on corpus luteum (CL) function using the novel microdialysis technique in vivo. Six cycling miniature pigs were monitored for estrus by daily plasma progesterone analysis and visual symptoms. On day nine of the cycle (day zero being the day of ovulation) the animals underwent surgery, and microdialysis tubing (vitafiber, Amicon U.S.A, cut off mol. wt. 1 million) were implanted in 17 corpora lutea. The inlets and outlets of all tubings were exteriorized and the entry and exit points of tubings in the CLs sealed with tissue glue. The afferent extension tubings were connected to a fraction collector and the system was continuously flushed with Ringer at a flow rate of 2.4 ml/h. After an initial flushout phase of 8 h, fractions were collected every half hour over 3 days. On days 10, 11 and 12 post estrus 12 CLs were stimulated for 4 h with 10(-7) M, 2 x 10(7) M and 4 x 10(-7) M human recombinant IFNgamma (Pharma Biotechnologie) respectively. Simultaneously, fractions were also collected from the remaining five unstimulated corpora lutea which served as controls. Progesterone concentrations in the dialysates were estimated by a sensitive enzymeimmunoassay (EIA). A significant increase (P < 0.01) in progesterone release was observed in all 3 days following stimulation. The progesterone increase was more marked on the first day of stimulation (1 x 10[-7] M) with the hormone levels rising further even after the end of stimulation. The overall increase in progesterone concentration was 2-fold on day 10 in comparison to 15-30% on subsequent days even though IFN concentrations for stimulation were 2- and 4-fold higher. In the unstimulated CLs, a gradual decline (P < 0.01) in progesterone levels were observed over days. In conclusion, these data provide evidence that the early conceptus signals its presence by way of IFNgamma to maintain the CL in pigs. 相似文献
999.
KE Sullivan DM McDonald-McGinn DA Driscoll CM Zmijewski AS Ellabban L Reed BS Emanuel EH Zackai BH Athreya G Keenan 《Canadian Metallurgical Quarterly》1997,40(3):430-436
OBJECTIVE: To investigate the association of polyarthritis and chromosome 22q11.2 deletions. METHODS: Eighty patients with chromosome 22q11.2 deletion syndrome followed up at The Children's Hospital of Philadelphia were examined for evidence of arthropathy or arthritis. Patients with chromosome 22q11.2 deletion syndrome and polyarthritis underwent laboratory evaluations of immunologic function to determine the relationship of their immunodeficiency to the polyarthritis. RESULTS: The prevalence of polyarthritis in patients with chromosome 22q11.2 deletion syndrome was markedly increased over the prevalence of polyarticular juvenile rheumatoid arthritis (JRA) in the general population. All 3 patients with polyarthritis had evidence of impaired T cell function. Two of the patients with polyarthritis also had IgA deficiency. CONCLUSION: The chromosome 22q11.2 deletion syndrome represents a primary T cell disorder which can be associated with a JRA-like polyarthritis. All 3 patients with polyarthritis had evidence of more extensive immunoregulatory derangements than those typically seen in patients with chromosome 22q11.2 deletion, and these derangements may have predisposed to the development of polyarthritis. 相似文献
1000.
The short-term tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol), were compared with that to amalgam using a previously devised experimental model. In 24 premolar teeth of beagle dogs (47 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periradicular lesions. On each root, an apicoectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 2 weeks (23 roots) and 1 week (24 roots); they were then prepared for histological examination. The tissue response to amalgam fillings after 2 weeks and 1 week was marked by moderate or severe inflammation on all roots, and extended to < or = 0.5 mm or > 0.5 mm in 15 out of 16 roots. In contrast, after 2 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation, while the tissue response to Vitrebond was the best of the three materials, and was also the least extensive. After 1 week, the overall best tissue response was with Vitrebond, followed by Kalzinol. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were not statistically significant (P < 0.02). However, the differences between materials for both time periods with no inflammation or inflammation extending < 0.2 mm when compared with that with inflammation extending > 0.2 mm (< or = 0.5 mm or > 0.5 mm) were statistically significant (P < 0.01). Apart from amalgam, in which healing was marked by the persistence of a localized focus of inflammation adjacent to the root-end filling, even though there were intersample variations, there was little overall difference in the temporal and qualitative healing response to Vitrebond and Kalzinol. Both Vitrebond and Kalzinol have potential as root-end filling materials, as the tissue response was considerably more favourable than that to amalgam even in the short-term. 相似文献