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81.
Among 407 New England Medical Center Posterior Circulation Registry (NEMC-PCR) patients, 59% had strokes without transient ischemic attacks (TIAs), 24% had TIAs before strokes, and 16% had only posterior circulation TIAs. Embolism was the commonest stroke mechanism accounting for 40% of cases (24% cardiac origin, 14% arterial origin, 2% had potential cardiac and arterial sources). In 32%, large artery occlusive lesions caused hemodynamic brain infarction. Stroke mechanisms in the posterior and anterior circulation are very similar. Infarcts most often included the distal posterior circulation territory (rostral brainstem, superior cerebellum and occipital and temporal lobes), while the proximal (medulla and posterior inferior cerebellum) and middle (pons and anterior inferior cerebellum) territories were equally involved. Infarcts that included the distal territory were twice as common as those that included the proximal or middle territories. Most distal territory infarcts were attributable to embolism. Thirty day mortality was low (3.6%). Embolic stroke mechanism, distal territory location, and basilar artery occlusive disease conveyed the worst prognosis.  相似文献   
82.
INTRODUCTION—There is a variable relation betweenangiographic vasospasm and delayed ischaemic neurological deficit(DIND). Magnetic resonance (MR) techniques have the potential toinvestigate the haemodynamic, metabolic, and structural changesoccurring with these complications. These techniques have been appliedto study DIND in patients recovering from subarachnoid haemorrhage.
METHODS—Fifteen studies were performed on 11 patients, 10 with DIND. Vasospasm was diagnosed angiographically orwith transcranial Doppler. The MR protocol consisted of T2 weightedimaging, contrast enhanced dynamic perfusion scanning, TI weightedimaging, and two dimensional localised proton spectroscopy. Relativecerebral blood volume maps were generated from perfusion scans.Metabolite ratios were calculated from proton spectra.
RESULTS—All patients had cortical oedema onT2 weighted images, significantly more pronounced in patients of poorclinical grade (p<0.01). Spectra were normal in good grade patients.Lactate was increased and N-acetyl aspartate decreased in the poorgrades, significantly worse in grade 4 compared with grade 3 patients(p<0.05). Spectral changes also correlated with the severity of oedema(p<0.05). Relative blood volumes were significantly higher inoedematous regions of poor compared with good grade patients (p<0.05).Lactate was seen in regions of the brain with increased relative blood volume.
CONCLUSIONS—Despite the paramagnetic effects ofhaemorrhage, or of the coils and clips used to treat aneurysms, thisstudy demonstrates that patients recovering from subarachnoidhaemorrhage can undergo complex MR studies. Oedema, lactate, andincreased relative blood volume correlate well with each other and withDIND and poor clinical grade.

  相似文献   
83.
Tension pneumocephalus is an uncommon but life-threatening complication of craniotomy which requires urgent diagnosis and treatment. It most often occurs perioperatively following subsequent anaesthesia using nitrous oxide. All previously reported postoperative cases followed posterior fossa or upper spinal cord surgery. Only two cases associated with frontal craniotomy have been reported since 1972, both occurring intraoperatively.  相似文献   
84.
脂联素与妊娠期糖尿病巨大儿发生关系的研究   总被引:1,自引:0,他引:1  
妊娠期糖尿病孕妇中巨大儿发生率明显高于正常孕妇,巨大儿是妊娠期糖尿病最多见的围产儿并发症,高血糖-高胰岛素学说是其基本的发病机制.脂联素、瘦素、肿瘤坏死因子-α、胰岛素样生长因子、成纤维细胞生长因子-Ⅱ、胰岛素抵抗等因素的参与加剧了妊娠期糖尿病,同时这些因素也与胎儿的生长发育密切相关,其以各种方式参与了巨大儿的发生.其中,脂联素可能起着重要作用.脂联素是调节胰岛素和糖代谢的关键因子,而胎儿的生长发育受胰岛素和糖代谢的影响,因此,脂联素可能是调节胎儿宫内发育的候选因子之一.胎盘组织中存在脂联素基因的表达,妊娠期糖尿病孕妇胎盘脂联素基因mRNA表达水平显著降低,表明妊娠期糖尿病孕妇内分泌环境的变化不但严重地影响着胎盘基因的表达,而且能通过影响胎盘调节干扰胎儿的生长发育.  相似文献   
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86.
BACKGROUND: Postpartum hospital stays seem likely to remain limited even under new laws which mandate that insurers cover 48-hour hospitalization after uncomplicated delivery. Clinicians, who are increasingly practicing in capitated arrangements, need better information to maximize clinical benefit to mothers and newborns using finite resources. OBJECTIVE AND INTERVENTIONS: This study's aim was to evaluate the clinical outcomes, patient perceptions, and costs of a revised model of perinatal care services. In this model, a new postpartum care center was established for routine follow-up of newborns within 48 hours after hospital discharge, educational efforts were shifted from the postpartum hospitalization to the prenatal period, and lactation consultant hours were increased. DESIGN AND PARTICIPANTS: Controlled, nonrandomized (double cohort) study that compared mothers and newborns with hospital stays of 48 hours or less during the Baseline Care (preintervention) study period (N = 344) with those under the Revised Care (postintervention) study period (N = 456). SETTING: The Hayward, California, medical center of Kaiser Permanente, a nonprofit health maintenance organization. DATA COLLECTION: Telephone interviews were attempted with all mothers 3 weeks after delivery. Data on rehospitalizations, emergency department (ED) and clinic visits, and costs during the first 14 postpartum days were collected from computerized databases and chart review. OUTCOME MEASURES: The combined clinical outcome was defined as any undesirable health event, including rehospitalization, an ED visit, or an urgent clinic visit by either the mother or newborn within the first 14 days postpartum, or breastfeeding discontinuation within the first 21 days postpartum. Maternal satisfaction and costs were also studied. RESULTS: Of 876 attempted interviews, 800 were completed (91%). Analyses were adjusted for age, race, education, parity, breastfeeding experience, and other relevant variables. Among the interviewed mother-newborn pairs, 45% in the Revised Care group experienced the combined clinical outcome, compared with 52% in the Baseline Care group. Newborns in the Revised Care group (29%) were significantly less likely to make urgent clinic visits during the first 14 days of life than those in the Baseline Care group (36%). There were no differences between groups in newborn ED visits or rehospitalizations, maternal clinical outcomes, or breastfeeding continuation. Mothers in the Revised Care group expressed higher satisfaction with the newborn's care, the amount of information they received about newborn care and breastfeeding, and the amount of help they received with breastfeeding. Planned hospital care, planned follow-up visits, and unplanned care costs decreased by $149 per delivery, while the new prenatal class and increased lactation consultant services cost $58 per delivery, for an estimated overall reduction in cost. CONCLUSIONS: We conclude that the revised model of perinatal care in this health maintenance organization medical center improved clinical outcomes and maternal satisfaction for low-risk mothers and newborns without increasing costs.  相似文献   
87.
88.
Quadrilateral space syndrome: a rare cause of shoulder pain   总被引:1,自引:0,他引:1  
Cormier  PJ; Matalon  TA; Wolin  PM 《Radiology》1988,167(3):797-798
The authors report a case of quadrilateral space syndrome in a baseball pitcher. The diagnosis was made by means of subclavian arteriography performed with the arm in abduction and external rotation. This entity is a rare cause of shoulder pain caused by occlusion of the posterior humeral circumflex artery in the quadrilateral space.  相似文献   
89.
The authors tested the effectiveness of orally administered delta-9-tetrahydrocannabinol (THC) as compared to prochlorperazine for the alleviation of symptoms, such as vomiting and nausea, experienced by patients receiving radiotherapy. The test subjects rated the severity of their illness, as well as the extent of their subsequent moods, their level of concentration, their amount of physical activity, and their desire for social interaction. They chose the drug they preferred and recorded its side effects. The use of THC was slightly more beneficial than the use of prochlorperazine.  相似文献   
90.
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