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81.
Hematologic disorders in pregnancy are relatively common and encompass a wide spectrum of clinical conditions. The treatment and obstetric management of the majority of these diseases are well established, although controversy exists in areas such as sickle cell disease and ITP. Once the diagnosis of a specific disorder is confirmed, therapy is directed toward improved perinatal outcome. Recent advances in prenatal diagnostic techniques make in utero diagnosis feasible for most of the inherited disorders and aid in genetic counseling. 相似文献
82.
Thermoregulatory heat-loss responses at high ambient temperatures were studied in intact cats and those with bilateral electrolytic lesions in the pontine tegmentum during wakefulness (W), slow-wave sleep (SWS), paradoxical sleep (PS) and PS without atonia induced by the lesions. Panting (respiratory rate 90/min) was present W, SWS, and in some cases, during PS. The percentage of the PS episodes with panting was directly related ambient temperature. In intact cats at 30 °C, panting occurred in 8% of the PS episodes; at 35 °C, in 52%, and at 40 °C, in 77%. The percentage of PS episodes with panting higher in the pontine-lesioned cats (90% at 35 °C), probably another indication of the altered thermoregulation of such animals. Thermoregulatory responses to heat load, and thermoregulation in general, have previously been shown to be suppressed in PS. Because hypothalamic thermosensitive neurons lack thermal responses during PS, the partial activation of heat-loss responses observed here may depend upon the function of extrahypothalamic brainstem areas. 相似文献
83.
In a series of over 500 cases of cerebellopontine angle tumors, 19 patients had bilateral neurinomas. Four of these tumors arose from the facial rather than the acoustic nerve. A conservative policy regarding surgery had been adopted in an effort to prevent hearing loss for as long as possible. Nevertheless, all patients operated on in this series are now totally deaf. The results of managing these patients surgically and conservatively are discussed. 相似文献
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86.
Winfried M. K. Amoakul Gerald J. Mahon Thomas A. Gardiner Leslie Frew Desmond B. Archer 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1992,230(6):569-574
This study describes ultrastructural changes in the pigmented hooded Lister rat retina, 3–12 months following X-irradiation with single doses of between 200 and 2000 cGy. The extreme radiosensitivity of the photoreceptor cells was underlined by the continued manifestation of fine structural changes and cell death up to 6 months post-radiation in animals receiving doses above 500 cGy. The retinal pigment epithelial (RPE) cells were more radioresistant than photoreceptors and RPE cell loss was only observed at doses of more than 1500 cGy. One year after irradiation with 1500 cGy the retinal vasculature showed capillary occlusion with some evidence of recanalisation. Telangiectasia was observed in the large retinal veins. Although the inner retinal neurones and glia1 cells showed no evidence of direct radiation damage, the nerve fibre layer adjacent to occluded retinal vessels demonstrated ultrastructural evidence of ischaemic neuropathy and retinal oedema. At doses above 1500 cGy the choriocapillaris showed platelet aggregation and capillary loss. 相似文献
87.
We all work in a multigenerational workforce. With extremes in generations, skills are needed to foster understanding among staff. There are many myths and realities about the age-related generations. While there are challenges in working in a multigenerational workforce, the generational differences tend to be exaggerated while the similarities are overlooked. A better understanding of these generations allows us to prevent communication breakdown and to close the communication gaps where they exist, creating a unit of harmony rather that discontent. 相似文献
88.
预测哪些人可能因急性发病而需要急诊入院,已成为英国国家医疗卫生服务体系(NHS)的一个重要话题。卫生部门将那些患有复杂的慢性疾病,经常不定期地去二级医疗机构就医的人们视为高危人群。确定这些人之后,社区护理员或其他卫生人员将通过“个案管理”的方法照顾他们。“个案管理”此前被定义为“对疾病尚未控制或所需费用昂贵的患者进行加强医疗计划”。社区护理人员可来自任何护理部门,但一般认为社区护士更能胜任这一角色。此方法能够减少可避免的急诊入院患者数量,并有助于实现到2008年3月减少5%急诊住院床位日的公共医疗服务目标。但是,如何才能界定需要急诊入院的高危人群呢? 相似文献
89.
Bouras Constantin; Hof Patrick R.; Giannakopoulos Panteleimon; Michel Jean-Pierre; Morrison John H. 《Cerebral cortex (New York, N.Y. : 1991)》1994,4(2):138-150
Detailed analyses of the neuropathologic changes in the cerebralcortex of elderly individuals and Alzheimer's disease patientshave demonstrated that certain components of the neocorticaland hippocampal circuits are likely to be selectively vulnerable.Based on the distribution of neurofibrillary tangles (NFTs)and senile plaques, it has been proposed that a global cortico-corticaldisconnection leads to the loss of integrated functions observedin Alzheimer's disease. In order to investigate the distributionof lesions associated with aging as well as with the earliestsymptoms of senile dementia, we performed a quantitative neuropathologicavaluation of a large series of elderly patients representingthe entire autopsy population for the year 1989 from a geriatrichospital. Among the 145 cases quantitatively assessed, therewere 102 nondemented patients, 33 patients presenting clinicallywith globally intact intellectual function but early signs ofimpairment of specific cognitive functions, and 10 cases withsenile dementia of the Alzheimer type. All of the cases hadNFTs in layer II of the entorhinal cortex, regardless of theirclinical diagnosis, and most cases had some NFTs in the CA1field of the hippocampus. Severe pathologic changes within theinferior temporal neocortex were observed only in the dementedcases. The extent of amyloid deposition was not correlated withthe clinical diagnosis and seemed to be present in the neocorticalareas earlier than in the hippocampal formation. Also, severalcases contained NFTs without amyloid deposition, but amyloidnever occurred without NFTs. These results suggests that involvementof certain structures within the hippocampal formation is aconsistent feature of aging. Thus, involvement of the hippocampalformation may be a necessary, but not sufficient, conditionfor the clinical expression of dementia, which is likely tobe more closely related to the progressive degeneration of selectneuronal populations in the neocortex. 相似文献
90.
J Ansell V Klassen R Lew S Ball M Weinstein T VanderSalm N Okike I Gratz J Leslie A Roberts 《The Journal of thoracic and cardiovascular surgery》1992,104(1):117-123
The effectiveness of prophylactic desmopressin acetate in reducing hemorrhage after cardiopulmonary bypass operations is controversial. We conducted a prospective, randomized, placebo-controlled, double-blind trial to determine its effectiveness and safety in such patients. Eighty-three evaluable patients undergoing valvular heart operations were randomized to receive desmopressin (0.3 microgram/kg) (41) or placebo (42) after cardiac bypass. Demographic characteristics were similar in both groups. There was no significant difference in total 24-hour blood loss between groups (desmopressin 1064.8 +/- 647.1 ml versus placebo 844.4 +/- 507.6 ml; p greater than 0.05), or in the requirement for red blood cell, platelet, or fresh frozen plasma transfusion, or for reexploration for control of hemorrhage. Neither was there a difference in the occurrence of thrombotic complications between groups. Analysis of factor VIII activity, von Willebrand factor, or von Willebrand factor multimers failed to show significant correlations with blood loss or differences between groups except for factor VIII activity, which was significantly higher in the desmopressin group 1 hour after operation than in the placebo group. A detailed comparative analysis of similar trials to determine the reasons for different outcomes suggests that desmopressin should not be used routinely as a prophylactic agent to reduce postsurgical hemorrhage, but that it may be beneficial when used in patients who already manifest excessive bleeding postoperatively. 相似文献