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1.
Lorraine Greaves Nancy Poole Natalie Hemsing 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》2019,48(1):90-98
Rates of smoking during pregnancy remain high in Canada, and cessation rates are low among women who are younger than 24 years and who are socially disadvantaged, that is, have few social and economic resources because of poverty, violence, or mental health issues. On the basis of findings from literature reviews and consultation with policy makers, we developed and operationalized four approaches that can be used by health care providers to tailor interventions for tobacco use in pregnancy. These four approaches are woman centered, trauma informed, harm reducing, and equitable. Public health initiatives that address smoking in young and socially disadvantaged women could be more sharply focused by shifting to such tailored approaches that are grounded in social justice aims, span pre- and postpregnancy periods, and can be used to address women’s social contexts and concerns. 相似文献
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Studies of the rate of clearance of a gellan gum formulation (Gelrite) radiolabelled by the inclusion of technetium-99m labelled diethylenetriaminepentaacetic acid were carried out in volunteer subjects and in rabbits. Disposition was followed by gamma scintigraphy and compared with 0.5% w/v hydroxyethylcellulose (HEC) solution and isotonic saline administered to the same subjects. Clearance of all solutions was found to follow bi-exponential kinetics with differences in clearance rates between the two species studied. A significant retention of the gellan gum formulation compared to HEC (p = 0.006) or saline (p = 0.009) was noted in man, but not in the rabbit. In this latter species the HEC showed greater retention compared to Gelrite. The species-specific differences in the precorneal residence of the formulations are attributed to the different physiological responses following instillation of solutions into the eye. 相似文献
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INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
5.
Recent evidence suggests that mast cell derived mediators other than histamine are likely to be involved in the pathogenesis of physical urticarias. Much of the work has been performed in idiopathic cold contact urticaria where the presence of neutrophil and eosinophil chemotactic factors, and platelet activating factor-like lipid substances have been previously demonstrated. Now, an increase in prostaglandin D2 measured by GC-MS has been demonstrated in venous blood draining the cold challenged area. This appeared a few minutes later than histamine, but then both substances paralleled the onset, development and subsidence of the urticarial reaction. There appeared to be no quantitative relationship between histamine and PGD2 release. A similar rise in histamine and PGD2 occurred on heat challenge of a subject with the rare localized form of heat urticaria. This rise of both substances was considerably reduced after combined treatment with induction of tolerance and oral indomethacin. The concentrations of PGD2 measured suggested that it plays an indirect role. 相似文献
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Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
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Gamma scintigraphy was used in twelve healthy volunteers to establish whether the time of dosing of Liquid Gaviscon relative to a meal influenced its therapeutic action. Indium-113m labelled Liquid Gaviscon was administered to fasted subjects, 30 min after a technetium-99m labelled meal or immediately before ingestion of the meal. The time for 50% of the Gaviscon to empty from the stomach was 0.36 +/- 0.13 h, 3.10 +/- 0.31 h and 0.68 +/- 0.04 h (s.e.m.), respectively. The preparation was found to empty rapidly from the fasted stomach and could not be floated on a meal consumed subsequently. For raft formation to occur, Liquid Gaviscon should be taken 30 min after a meal. 相似文献