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991.
Cerebral blood flow in depressed patients: a methodological comparison of statistical parametric mapping and region of interest analyses 总被引:5,自引:0,他引:5
Bonne O Louzoun Y Aharon I Krausz Y Karger H Lerer B Bocher M Freedman N Chisin R 《Psychiatry research》2003,122(1):49-57
Functional brain imaging has assumed a leading role in neuropsychiatric research. However, findings reported for mental disorders often vary. Whether this reflects diversity in pathophysiology or heterogeneity of imaging techniques and data-analytic procedures is still unknown. This study compares region of interest (ROI) and statistical parametric mapping (SPM) analyses of a Tc99m-HMPAO single photon emission computed tomography (SPECT) imaging study of 23 depressed and 21 control subjects. Reduced regional cerebral blood flow (rCBF) was demonstrated by both methods in the right parietal and occipital lobes, but additional regions were identified only on ROI analysis (left temporal) and only on SPM analysis (left parietal). To investigate the contribution of SPM spatial normalization to these discrepancies, further ROI analyses were performed, applying the original ROI templates to normalized images, and applying regions identified by SPM to the original images. This study demonstrated considerable overlap in findings of SPM and ROI analyses. Differences between these methods may be mostly related to subjective placement of ROIs in ROI analysis, and standardized warping inherent in normalization in SPM. Given the advantages and drawbacks of each procedure, the choice of methodology should be determined in accordance with the study design, and complementary use of both methods may be considered. 相似文献
992.
We studied the effects of pentylenetetrazole (PTZ) on brain amino acid metabolism in mice. Administration of this convulsant did not change forebrain concentrations of amino acids, but when treated animals also received an injection of [15N]leucine, which served as a tracer of brain nitrogen metabolism, total (14N+15N) forebrain [leucine] exceeded control and [glutamate] and [aspartate] were less than control, as were forebrain concentrations of [15N]glutamate and [2-15N]glutamine. These data suggest greater uptake of [15N]leucine but diminished transamination of leucine to glutamate in experimental mice. In contrast to the [15N]leucine studies, which were associated with increased brain [leucine], the administration of [15N]alanine did not alter levels of alanine, glutamate or glutamine. However, label appeared in [2-15N]glutamine much more readily with [15N]alanine than with [15N]leucine as precursor and the ratio of enrichment in [2-15N]glutamine/[15N]alanine was much higher than that in [2-15N]glutamine/[15N]leucine, a finding that is compatible with preferential metabolism of alanine in astrocytes, which are the primary site of brain glutamine synthetase. We conclude that PTZ treatment favors the uptake of selected amino acids such as leucine but also diminishes transamination of leucine to yield glutamate via branched-chain amino acid transaminase. PTZ treatment may favor the "reverse" transamination of 2-keto-isocaproate (KIC), the ketoacid of leucine, to form leucine and to consume glutamate. A net result of these processes may be to enable the brain more readily to dispose of the glutamate that is released from neurons during convulsive activity. 相似文献
993.
Selten JP Cantor-Graae E Nahon D Levav I Aleman A Kahn RS 《Schizophrenia Research》2003,63(1-2):131-135
AIM: Maternal stress during pregnancy is a possible risk factor for schizophrenia in the offspring. Using data from the Israel Psychiatric Registry we examined the impact of wars in Israel. METHOD: Retrospective birth cohort study. RESULTS: Relative risks for cohorts exposed to Six-Day War and Yom Kippur War were 0.98 (95% CI: 0.85-1.13) and 1.00 (0.86-1.16). CONCLUSION: The evidence for maternal stress as a risk factor for schizophrenia remains insufficient. 相似文献
994.
Myocardial revascularization for acute myocardial infarction: benefits and drawbacks of avoiding cardiopulmonary bypass 总被引:3,自引:0,他引:3
Locker C Mohr R Paz Y Kramer A Lev-Ran O Pevni D Shapira I 《The Annals of thoracic surgery》2003,76(3):771-6; discussion 776-7
BACKGROUND: Coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI) is associated with increased mortality compared with CABG in non-AMI patients. Operating without cardiopulmonary bypass (CPB) might reduce this mortality. METHODS: Between January 1992 and December 1998, 225 patients underwent CABG within 7 days of AMI, 119 with CPB and 106 without. The two groups were similar regarding age, gender, left ventricular dysfunction, and incidence of cardiogenic shock. Mean number of grafts per patient was 3.1 in the CPB group, and 1.7 in the no-CPB group (p < 0.0001). RESULTS: Operative mortality in the CPB group was 12% compared with 3.8% without CPB (p = 0.027). Independent predictors of operative mortality were preoperative use of intraaortic balloon counterpulsation (IABP), nonuse of internal thoracic artery (ITA) to the left anerior descending artery, and the use of less than three grafts. Mortality of patients operated on with CPB within 48 hours of AMI was significantly higher (16.5% vs 4.3%, respectively; p = 0.044). However, patients operated on after 48 hours had similar mortality (5.8% vs 3.4%, respectively). Follow-up ranged from 6 to 84 months. Five-year survival (Kaplan-Meier) of both groups was similar (81%). Patients operated on with CPB had similar rates of recurrent angina; however, they had lower prevalence of reinterventions (0.8% vs 6.3%; p = 0.03). CONCLUSIONS: Our study suggests that CPB can be used safely for most patients referred for CABG within the first week of AMI. However, for emergency patients operated on within the first 48 hours of symptom onset, we advocate avoiding CPB because it is associated with lower operative mortality. 相似文献
995.
996.
OBJECT: Surgery for refractory epilepsy often bestows significant relief but may cause memory impairment. The risk of postoperative memory loss can be determined by the intracarotid amobarbital procedure, or the Wada test. Chemical inactivation of the hemisphere on the side of the lesion is usually performed first, followed by inactivation of the contralateral hemisphere. Patients who demonstrate adequate memory capacity of the contralateral hemisphere following deactivation of the ipsilateral hemisphere are considered good candidates for anterior temporal lobectomy. Evidence for the contribution of deactivating the contralateral healthy hemisphere remains inconclusive. METHODS: The authors analyzed results in 32 patients with intractable epilepsy who had undergone a bilateral Wada test followed by an anterior temporal lobectomy and in whom the findings of both pre- and postsurgical neuropsychological evaluations were available. The Wada memory scores were correlated with the difference in scores between pre- and postsurgical standardized memory test scores. CONCLUSIONS: Analyses revealed no significant relationship between the Wada memory scores in the contralateral hemisphere and postsurgical changes in memory abilities. There was, however, a significant negative correlation between the Wada memory score in the ipsilateral hemisphere and postsurgical memory changes, particularly in patients with right hemisphere epileptogenic lesions (p = 0.0007). The results of this study are discussed vis-à-vis two theories of hippocampal function, and the authors stress the importance of the functional status of the surgical hemisphere in the prediction of postsurgical memory changes. 相似文献
997.
Candidal endocarditis is an uncommon and serious complication of invasive Candida infection in neonates. The aim of this study was to further characterise candidal endocarditis in neonates. Between 1995 and 2000, 56 patients were diagnosed with Candida bloodstream infections (CBSI) in the Neonatal Intensive Care Unit of Schneider Children's Medical Center of Israel. Five of them (9%) developed mycetoma of the right atrium. None of the patients had congenital heart disease or a central venous catheter in the right heart at the time of diagnosis. All were treated with amphotericin B alone or in combination with other antifungals, without surgical intervention. One patient died of the disease and one died later of polymicrobial sepsis and necrotizing enterocolitis. A review of the literature since 1980 yielded an additional 25 cases of candidal endocarditis. For the whole sample (n = 30) survival rate was 73.1%. Six of the 10 patients treated with antifungal agents and surgery survived (60%), compared with 13 of the 20 patients treated only medically (65%) (P = 1.0). Candida endocarditis in neonates differs from fungal endocarditis in adults in risk factors, clinical presentation and outcome. As the outcome of surgical and medical treatment are comparable, antifungal therapy alone may be a valid therapeutic option in high-risk cases. 相似文献
998.
Brook I 《ORL; journal for oto-rhino-laryngology and its related specialties》2003,65(2):117-120
This review describes the microbiology, diagnosis and management of deep facial infections and Lemierre syndrome. The origins of most of these infections are odontogenic infections that spread to fascial spaces of the lower head and upper neck. Other sources include pharyngotonsillar, nasal, otologic, salivary gland and dermatologic infections, hematogenic spread, cervical adenitis and trauma. These space infections can be divided into those around the face (masticatory, buccal, canine and parotid), the suprahyoid area (submandibular, sublingual and lateral pharyngeal) and the infrahyoid region or lateral neck (retropharyngeal and pretracheal spaces). The organisms accounting for these infections are aerobic and anaerobic that arise from the oropharyngeal flora. Complications of these infections can be life threatening and can result from hematogenic or direct spread. Complications that arise following local extension include suppurative jugular thrombophlebitis, cavernous sinus thrombosis, carotid erosion, maxillary sinusitis and osteomyelitis of the jaws. Management includes surgical drainage and antimicrobial therapy. 相似文献
999.
Bar J Davidi O Goshen Y Hod M Yaniv I Hirsch R 《American journal of obstetrics and gynecology》2003,189(3):853-857
OBJECTIVE: Pregnancy outcome and the effect of pregnancy on cardiac function were assessed in women cured of childhood cancer. STUDY DESIGN: Forty women who received doxorubicin as part of a chemotherapy protocol for a neoplastic disorder in childhood were followed up at the same center during pregnancy and after delivery. RESULTS: Thirty-seven women (72 pregnancies) completed follow-up. Pregnancy outcome was favorable in the 29 women with fractional shortening values of >or=30% before pregnancy, and their myocardial function was sustained. In 8 women with fractional shortening of <30% before pregnancy, pregnancy outcome was less favorable; a 19% decrease in fractional shortening was observed after pregnancy, and this finding was not significant (P=.08). CONCLUSION: Pregnancy outcome in women who received doxorubicin for malignancy in childhood is generally favorable. However, those with baseline left ventricular dysfunction should be considered at increased risk for worse pregnancy outcome and further deterioration in myocardial function. 相似文献
1000.
Many clinicians advise their patients to increase the dose of inhaled corticosteroids during acute asthma exacerbations, without strong clinical evidence supporting this treatment. This study investigates the effectiveness of inhaled corticosteroids in controlling acute asthma exacerbations in children at home. The study population consisted of children with mild intermittent, mild and moderate persistent asthma aged 1 to 14 years who were treated in our outpatient clinic with inhaled budesonide for 1 year. After participating in an asthma education session, the parents were instructed to initiate treatment with inhaled budesonide at the first signs of asthma exacerbation, starting with 200 to 400 microg budesonide, in combination with beta-2 agonists 4 times a day and followed by a decrease in the dose in 4 to 8 days. Asthma status and peak expiratory flow rates were measured in the 3 monthly follow-up visits. Only children who complied with the treatment regimen and came for follow-up visits regularly were included in the final analysis. One hundred fifty children used our treatment protocol with inhaled budesonide to control their asthma attacks. Clinical improvement of asthma symptoms was achieved after a mean of 1.8 +/- 0.7 days from the beginning of treatment. The parents were able to control 94% of the 1,061 episodes of asthma exacerbation occurring during a cumulative follow-up period of 239 years. In the 3-month period before enrollment, 101 children (67%) had used oral corticosteroids to control their asthma attacks and 50 (33%) were hospitalized. During the entire follow-up period, only 11 children (7%) used oral corticosteroids, and none of the children were hospitalized. The present study demonstrates that children with asthma can control their exacerbations at home using inhaled corticosteroids (budesonide). Treatment, starting with relatively high doses followed by a rapid reduction in dose over 4-8 days, resulted in a decrease in the use of oral steroids and in hospitalization. To achieve good results, patient compliance is essential. 相似文献