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排序方式: 共有484条查询结果,搜索用时 12 毫秒
31.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
32.
A case of two secondary aneurysmal bone cysts arising in fibrous dysplasia during pregnancy is reported. Marked radiographic changes were seen in one lesion over a 3-week period. The development of these cysts during pregnancy strongly suggests that the hemodynamic and/or hormonal changes of pregnancy were responsible for their formation. 相似文献
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Unintended pregnancy and birth, frequently due to contraceptive non-use or misuse, continue to be important public health problems. A large body of literature has examined women's characteristics related to contraceptive use. However, much of what is known about men and contraception has been obtained or extrapolated from interviews with women. In this paper, we first present an overview of unintended pregnancy and the link with contraception. We explore gender considerations in contraceptive decision-making and discuss the literature of men's role in contraceptive attitudes and practices both in the developing countries and in the United States. Because individuals who make contraceptive decisions are actually part of couples, we examine the recent literature on couple communication and the role of partner influence on contraceptive practice. Finally, we propose a conceptual model that can be used for studying gender differences regarding factors that influence contraceptive use. The model is comprised of a variety of factors influencing contraceptive use that include; (1) knowledge of contraceptive methods, use, and effectiveness; (2) structural/access, institutional, and financial factors that may present barriers to contraceptive acquisition and use; and (3) socio-cultural factors. These sociocultural factors include: (a) attitude (beliefs, values, perceived risk of pregnancy, cognitive assessment/acceptability of pregnancy, masculinity ideology, self-esteem, and self-efficacy); (b) the influence of significant others, including partners, peers, and family; and (c) sociodemographic factors including age, ethnicity, marital status, education, and income. This model should be useful in identifying gender differences in knowledge, attitudes, and practices about contraception and pregnancy so that efforts to reduce unintended pregnancy can effectively target both women and men. 相似文献
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36.
The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy. 相似文献
37.
True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access. 相似文献
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39.
Eva Hradetzky Thomas M Sanderson Tsz M Tsang John L Sherwood Stephen M Fitzjohn Viktor Lakics Nadia Malik Stephanie Schoeffmann Michael J O'Neill Tammy MK Cheng Laura W Harris Hassan Rahmoune Paul C Guest Emanuele Sher Graham L Collingridge Elaine Holmes Mark D Tricklebank Sabine Bahn 《Neuropsychopharmacology》2012,37(2):364-377
Administration of the DNA-alkylating agent methylazoxymethanol acetate (MAM) on embryonic day 17 (E17) produces behavioral and anatomical brain abnormalities, which model some aspects of schizophrenia. This has lead to the premise that MAM rats are a neurodevelopmental model for schizophrenia. However, the underlying molecular pathways affected in this model have not been elucidated. In this study, we investigated the molecular phenotype of adult MAM rats by focusing on the frontal cortex and hippocampal areas, as these are known to be affected in schizophrenia. Proteomic and metabonomic analyses showed that the MAM treatment on E17 resulted primarily in deficits in hippocampal glutamatergic neurotransmission, as seen in some schizophrenia patients. Most importantly, these results were consistent with our finding of functional deficits in glutamatergic neurotransmission, as identified using electrophysiological recordings. Thus, this study provides the first molecular evidence, combined with functional validation, that the MAM-E17 rat model reproduces hippocampal deficits relevant to the pathology of schizophrenia. 相似文献
40.
M. Kay Libbus Linda F. C. Bullock Teak Nelson Linda Robrecht Mary Ann Curry Tina Bloom 《Issues in mental health nursing》2013,34(9):927-938
This study used Landenburger's theory, a process of leaving and recovering from an abusive relationship, as a framework to interview 35 pregnant women identified as being at high risk for abuse. Results are reported on 18 women who disclosed active abuse during the study. Landenburger's model was not a good fit. Our participants became trapped and endured violent relationships if they perceived this was the best situation for their unborn child. Additionally the chaos, instability, and lack of resources experienced by these women likely contributed to their inability to complete the four phases described by Landenburger's model for non-pregnant women 相似文献