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991.
SR Oliver 《Canadian Metallurgical Quarterly》1995,310(6990):1318-1320
The National Childbirth Trust, along with other groups of health service users, is working with health professionals and researchers in planning clinical trials, setting priorities for research, systematically reviewing research reports, and getting research findings into practice. User groups may bridge the gap between the public and researchers by explaining research issues to a wide audience, presenting the needs and views of health service users to the research community, and suggesting how members of the public may be approached for their views directly. Service users recognise their need for training and support, and they call for development and evaluation of this work. 相似文献
992.
To characterize metabolic factors potentially associated with alcohol-induced heart disease, myocardial ethanol intermediary metabolism was studied in isolated, perfused rabbit hearts and whole heart homogenates. Results showed that intact rabbit hearts and homogenates of rabbit left ventricle incorporate carbon-14-labeled ethanol at 20 and 59 nmol/g/h, respectively, into a neutral lipid species that co-migrates with triacylglycerides in standard chromatographic solvent systems. After isolation and purification by thin layer chromatography in an apolar solvent system, the labeled species were identified by gas chromatographic-mass spectral analysis to be a family of fatty acid ethyl esters. Heat inactivation of incorporation and the kinetics of formation of products suggest that the process is enzymatic. Gas chromatography identified the fatty acid components as predominantly unsaturated moieties, especially oleic, linoleic, and arachidonic acids. These results provide insight into potential biochemical mechanisms contributing to the triacylglyceride accumulation, decreased beta oxidation of fatty acids, and other lipid abnormalities typical of effects of ethanol on the heart. 相似文献
993.
994.
The effects of Vinca alkaloids on the vas deferens have been examined after in vitro and in vivo administration. In the organ bath, vinblastine (1 X 10-4M for 4 hr) caused an increase in sensitivity to noradrenaline and biochemical, histochemical and ulstrastructural signs of noradrenaline depletion from the nerves supplying the outer longitudinal muscle layer. After intravenous injection of Vinca alkaloids the nerve fibres seemed less affected. It is concluded that the apparent resistance to the drugs in vivo is largely due to low tissue perfusion. 相似文献
995.
996.
The small intestine, large intestine, and cecum of 975 white-tailed deer (Odocoileus virginianus) from 83 localities in 13 southeastern states were examined for nematodes. In order of prevalence, the following parasites were found: Capillaria bovis, Eucyathostomum webbi, Monodontus louisianensis, Nematodirus odocoilei, Oesophagostomum venulosum, Trichuris sp, Cooperia punctata, Trichostrongylus longispicularis, Strongyloides sp, Cooperia oncophora, Cooperia spatulata, Cooperia sp, and Trichostrongylus calcaratus. Over one-half of the deer examined were free of intestinal nematodes, and most infected deer harbored few parasites. Of the most prevalent species, C bovis, N odocoilei, O venulosum, and Trichuris sp were widely distributed, whereas M louisianensis and E webbi were restricted in distribution. Severe pathogenicity was associated with only heavy Strongyloides sp infections in 2 penned deer. The findings of this study suggested that white-tailed deer of the Southeast are insignificant in the epizootiology of important intestinal nematodes of domestic livestock. 相似文献
997.
Although most subdural hematomas are considered to be venous in origin, they may also be of arterial origin. When subdural bleeding is due to the rupture of an intracranial aneurysm, most commonly at the middle cerebral or internal carotid arteries, the amount of subdural blood is usually small and of no clinical importance. We describe two patients with subdural hematomas secondary to rupture of an intracranial aneurysm, who needed prompt surgical treatment. The first patient had a left internal carotid artery aneurysm at the origin of the ophthalmic artery. In the second patient the aneurysm was at the anterior communicating artery and rebled into the subdural space directly through a right intraparenchymatous frontobasal hematoma. The most probable mechanism of subdural bleeding in our two patients was the existence of adhesions between the aneurysm and the arachnoid due to previous minor hemorrhages. The indication of cerebral angiography in a patient with subdural hematoma is based mainly upon the existence of meningeal signs, the presence of blood in more than one intracranial compartment or the rapid progression of bleeding. 相似文献
998.
999.
SR Lambert A Fernandes H Grossniklaus C Drews-Botsch H Eggers RG Boothe 《Canadian Metallurgical Quarterly》1995,36(2):300-310
PURPOSE: To compare the effects of a lensectomy with and without intraocular lens (IOL) implantation on a neonatal rhesus monkey eye. METHODS: A lensectomy and anterior vitrectomy was performed on 75 monkeys during the first 16 days of life; 21 of these monkeys also had an IOL implanted into the posterior chamber. The eyes were examined at regular intervals using biomicroscopy, applanation tonometry, and ophthalmoscopy. RESULTS: The pseudophakic monkeys were studied until they were 92.5 +/- 5.8 weeks of age and the aphakic monkeys until they were 80.4 +/- 5.7 weeks of age. Pupillary membranes (100% versus 55.5%; P < 0.01) and lens regeneration into the pupillary aperture (28.6% versus 5.6%; P = 0.02) occurred more often in the pseudophakic than the aphakic eyes. As a result, the pseudophakic eyes required more reoperations than the aphakic eyes to keep the visual axis clear (P < 0.01). There was not a significant difference in the incidence of ocular hypertension between the pseudophakic and aphakic eyes (9.5% versus 12.7%; P = 0.34). Pupillary capture of the IOL optic occurred in 52% and haptic breakage in 33% of the pseudophakic eyes. All of the eyes with broken haptics had a prominent Soemmerring's ring varying in maximum thickness from 0.6 to 2 mm. Nine of the haptics from the seven eyes with broken IOLs had eroded into the iris, two into the ciliary body, and one into the anterior chamber. CONCLUSIONS: Implanting an IOL into a neonatal monkey eye after a lensectomy and anterior vitrectomy increases the likelihood of a reoperation being necessary. Haptics frequently erode into the iris and ciliary body and may break because of stress placed on the optic-haptic junction by forward movement of the IOL. 相似文献
1000.
Passenger restraints reduce fatalities and serious injuries. Restraint systems alter the distribution of injuries seen in accident victims, and they cause a number of injuries. The distribution of injuries is dependent on the type of restraint. Automatic motorized shoulder belts are being used without the accompanying manual lap belt. This greatly reduces the effectiveness of the system and is equal to the two-point shoulder belt of the 1960s. Airbag injuries include abrasions to the face, neck, and chest; minor burns to the upper extremities; and chemical keratitis. Airbags have been shown to reduce injuries overall, especially when used in conjunction with a lap and shoulder belt. Elderly patients incur more rib and sternal fractures due to seat belts than do younger patients. Nevertheless, restraint systems are effective at reducing serious internal injuries in this population. Children who are too large for child safety seats but too small for adult seat belts are at increased risk for injury. Improvement in restraint systems for children in this age range is recommended. All pregnant women should be encouraged to wear seat belts because they reduce maternal injuries, and there is no evidence that they increase the risk of fetal loss. In view of the injury reduction associated with passenger restraint systems, emergency physicians should emphasize to their patients the importance of wearing seat belts. 相似文献