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991.
Almost two-thirds of health authorities believe their relationships with GPs have improved since the merger. Forty-four percent of LMCs think there has been no change, and 42 per cent report a deterioration. More than half the LMCs believe knowledge and understanding of GPs' contracts, and payments, have declined since the merger. 相似文献
992.
- In this study the impairment induced by hydrogen peroxide of vascular reactivity and the role of endogenous catalase in protection against this impairment was assessed in isolated rings of rat aorta.
- Incubation with hydrogen peroxide at 1 mM, but not at 0.1 mM, for 15, 30 or 60 min followed by washout depressed, in a time-dependent manner, the subsequent ability of endothelium-containing and endothelium-denuded rings to contract to phenylephrine.
- Incubation with 3-amino-1,2,4-triazole (50 mM, 90 min, followed by washout) to inhibit endogenous catalase had no effect by itself on subsequent phenylephrine-induced contraction. However, pretreatment with 3-amino-1,2,4-triazole did lead to a profound enhancement of the ability of hydrogen peroxide (1 mM, present for the final 30 min of the 90 min incubation, followed by washout) to depress phenylephrine-induced contraction in both endothelium-containing and endothelium-denuded rings.
- Incubation with hydrogen peroxide at 1 mM, but not at 0.1 mM, for 15, 30 or 60 min followed by washout inhibited, in a time-dependent manner, the subsequent ability of acetylcholine (10 nM–3 μM) to induce endothelium-dependent relaxation. Furthermore, incubation with hydrogen peroxide 1 mM (30 min, followed by washout) also inhibited relaxation induced by glyceryl trinitrate (1–100 nM) or isoprenaline (10 nM–3 μM) in endothelium-denuded rings.
- Incubation with 3-amino-1,2,4-triazole (50 mM, 90 min, followed by washout) had no effect by itself on relaxation induced by acetylcholine, glyceryl trinitrate or isoprenaline. In contrast, pretreatment with 3-amino-1,2,4-triazole led to profound enhancement of the ability of hydrogen peroxide (1 mM, present for final 30 min of the 90 min incubation) to block relaxation to acetylcholine, glyceryl trinitrate or isoprenaline.
- On the basis of the actions of 3-amino-1,2,4-triazole, it is likely that endogenous catalase plays an important role in the protection of vascular reactivity of rat aorta against oxidant damage by high (1 mM) but not lower (0.1 mM) concentrations of hydrogen peroxide. The data are consistent with the promotion of non-selective damage to the vascular smooth muscle cells by hydrogen peroxide, but endothelial damage may also be sustained.
993.
994.
Martin WJ 《CAP today / College of American Pathologists》1994,8(10):67-70
Neuropsychiatric diseases viewed as multifaceted expression of a dysfunctional brain in which atypical responses are evoked by various sensory inputs. Disease entities have traditionally been classified according to the predominant manifestation ( ) without regard to the overlapping features of many of the diseases (+/-). Thus, mild to moderate pain, mood, cognitive, and neurosomatic symptoms are frequently present in chronic fatigue syndrome (CFS) patients. Fibromyalgia syndrome (FMS) is listed as an example of a predominantly chronic pain syndrome. Affect (mood) disorders include depression (Depress.), anxiety, panic reactions, blunted affect, mania, etc. Schizophrenia (Schizo.) is listed as an example of a major cognitive psychosis. Autism as well as various forms of dementia would be included in this category. Irritable bowel syndrome (IBS) is an example of a neurosomatic disease. 相似文献
995.
John P. R. Keon Caroline S. James Samantha Court Catharine Baden-Daintree Andrew M. Bailey Raymond S. Burden Martin Bard John A. Hargreaves 《Current genetics》1994,25(6):531-537
The Magnaporthe grisea ERG2 gene, encoding 87 sterol isomerase, was isolated from a genomic library by heterologous hybridization to a fragment of the Ustilago maydis ERG2 gene. The isolated gene contained a reading frame of 745 bp which encoded a protein of 221 amino acids. The coding region was interrupted by a single putative 79-bp-long intron. The deduced amino-acid sequence exhibited similarity to the ERG2 gene products of U. maydis and of Saccharomyces cerevisiae, particularly in the central region of the proteins. The NH2-terminal of all three proteins contained a long stretch of amino acids that were strongly hydrophobic, suggesting that they may function by anchoring the protein to a membrane surface. The M. grisea ERG2 gene complemented a U. maydis deletion mutant in which the ERG2 gene had been removed using a one-step gene replacement procedure. The 87 sterol isomerase produced by the M. grisea ERG2 gene exhibited a level of sensitivity to the sterol biosynthesis inhibitor, tridemorph, similar to that of the enzyme derived from the U. maydis ERG2 gene. 相似文献
996.
Iain Taylor Martin White Gavin N. C. Kenny 《Journal of clinical monitoring and computing》1994,10(3):175-180
Summary Thirty one anaesthetists were supplied with a pharmacokinetic based target controlled propofol infusion system for evaluation. Twenty seven of 30 replies to a questionnaire sent to them indicated that the system had changed their use of propofol for maintenance of anaesthesia. The main reasons were greater ease of use and more confidence regarding the predictability of anaesthetic effects compared with manually controlled infusion. Data obtained from 770 patients anaesthetised with the system were analysed. The median maximum target concentration selected was 6.6 g/ml. Younger patients (18–35 yr) required significantly greater target concentrations than older patients (65–80 yr). The mean time during which the system was in maintenance mode, when the predicted blood concentration of propofol was held constant for at least one minute, was 26.1 minutes. The median number of alterations in propofol concentration was 6. The target controlled infusion system provided an inexpensive and acceptable method of delivering intravenous anaesthesia. 相似文献
997.
We have presented both technical and clinical data indicating that transvenous lead systems are comparable to standard epicardial ICD systems with respect to efficacy. In addition there may be a reduction in morbidity when compared with the standard epicardial implant. We have shown for the Endotak and Transvene systems that each has its own idiosyncrasies, advantages, and disadvantages. Other lead systems are too early in their clinical evaluations for such definitive statements to be made. Regarding long-term reliability, the issues of mechanical integrity of the insulation and conductor materials, as well as the stability (or otherwise) of sensing and defibrillating characteristics remains to be determined for all lead systems. Similarly, compatibility between lead systems and pulse generators made by different manufacturers cannot be assumed, but needs to be prospectively examined in rigorous clinical trials. 相似文献
998.
Rogers ES Danley KS Anthony WA Martin R Walsh D 《Journal of mental health administration》1994,21(1):42-51
This study reports on a systematic statewide effort to determine the residential needs and preferences of two important groups: primary consumers of mental health services and family members of consumers. Two comparable surveys regarding the residential needs of consumers were conducted. In all, 314 consumers and 459 family members participated in the survey. A comparison of the preferences of family members and consumers suggests that family members more often prefer congregate living situations and more staff support than do consumers. Consumers more often express a desire to reside by themselves without staff and without other persons who are mentally ill. While the direct comparison of preferences from these two constituencies has limitations, these data do suggest significant variability in needs and preferences voiced by consumers and their family members; discrepancies that need to be addressed by mental health policymakers and planners. 相似文献
999.
We report eight cases of vein of Galen aneurysmal malformation (VGAM) assoicated with a Chiari type I malformation. In four cases magnetic resonance imaging (MRI) or computed tomography performed in the neonatal period did not demonstrate the posterior fossa anomaly, which appeared on later scans. In the other cases the MRI was performed in infancy and the anomaly was already present. We compared the venous phases of the posterior fossa angiograms and the MRI in these patients. In all eight cases, the angiograms showed a reflux in the cerebellar veins, via the petrous vein, associated with a uni-or bilateral stenosis or thrombosis of the distal posterior dural sinuses. Furthermore, in two cases the posterior fossa returned to normal on MRI following endovascular treatment, while in three cases the herniation of the cerebellar tonsils decreased after the embolization. Tonsillar prolapse becomes irreversible when the venous outlet is incapable of taking the flow even when the VGAM has been treated adequately. In eight additional cases of VGAM for which MRI and angiogram studies were available and in which stenosis or thrombosis of posterior dural sinuses was present without tonsillar prolapse, no reflux into the cerebellar veins was shown. We suggest that the posterior fossa hydrovenous congestion is a result of inadequate venous drainage and that the tonsillar descent is reversible if adequate venous drainage is reconstituted following therapeutic embolization of the fistula. Tonsillar prolapse is not a consequence of mass or raised intraventricular pressure. Our observation suggests that in some other conditions, the Chiari I malformations may be secondary to early hydrovenous dysfunction of the posterior fossa. 相似文献
1000.