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This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries (MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres. During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1: left MCA = 3.27 ± 1.9%; right MCA = 3.63 ± 2.1%; task 3: left MCA = 2.42 ± 0.7%; right MCA = 2.56 ± 1.3%); the negative emotional task was accompanied by a significantly higher increase in the right (11.31 ± 1.6%) than in the left MCA (4.72 ± 3.7%; analysis of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler ultrasound and suggest the involvement of the right hemisphere in emotional processing. Received: 4 March 1999 Received in revised form: 29 June 1999 Accepted: 5 August 1999  相似文献   
43.
Live donor renal transplantation has many advantages including greater graft and patient survival, shorter waiting periods, improved human leukocyte antigen matching, and less cold ischemia. Until recently, disincentives from the operation, such as prolonged hospitalization, postoperative pain, and significant convalescence, have deterred live donor renal transplantation. This article describes the technique of laparoscopic live donor nephrectomy and briefly reports the results. The procedure has resulted in improved postoperative recovery and shorter convalescence, with no effect on recipient renal function.  相似文献   
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Summary Here ditary cerebral hemorrhage with amyloidosis Dutch type (HCHWA-D) is characterized clinically by recurrent strokes and pathologically by deposition of amyloid (A) in cerebral vessel walls and, to a lesser extent, in the neuropil. Distinct from Alzheimer's disease, amyloid formation in HCHWA-D is not associated with neurofibrillary changes. Since a central issue in the pathophysiology of Alzheimer's disease and related conditions is the role of A in the neurodegencrative process, we investigated HCHWA-D brains for the presence of neuritic abnormalities using antibodies to ubiquitin and to phosphorylated neurofilaments. The study showed that amyloid deposits in the vessel walls and in the neuropil were surrounded by abnormal ubiquitinated neurites, suggesting that A deposition induces neuritic changes.Supported by the Italian Ministry of Health. Department of Social Services, and by N.I.H. Grants AG05891 and AG08721 (to B.F.)  相似文献   
46.
Summary We report 48 patients operated on for lumbar disc herniation in the second decade of life (aged 13–20 years) in our Neurosurgical Division. To analyze the clinical and diagnostic features and surgical outcome of the disease in teenagers and to point out any differences from adults, we made a detailed study of over 900 juvenile cases and compared them with 11000 adult cases reported in the literature. Low-back pain proved to be less frequent among youngsters both as a first symptom and at diagnosis, while sensorimotor deficits have the same frequency in the two age groups. Herniation occurs more often at L4–L5 and is more frequently median among teenagers. The long-term surgical results in children and adolescents are better than in adults.  相似文献   
47.
Laparoscopic management of urachal cysts in adulthood   总被引:3,自引:0,他引:3  
PURPOSE: Managing persistent and symptomatic urachal anomalies requires wide surgical excision. Such intervention is recommended to prevent symptom recurrence and complications, most notably malignant degeneration. However, traditional open excision is associated with significant morbidity and prolonged convalescence. We report our experience with the laparoscopic excision of urachal remnants as a less morbid, minimally invasive surgical alternative. MATERIALS AND METHODS: Between October 1993 and December 1999, 4 patients with a mean age of 43.3 years who had a symptomatic urachal cyst underwent laparoscopic radical excision of the urachal remnant. Using 2, 10 mm. and 1 or 2, 5 mm. ports the urachus and medial umbilical ligaments were divided at the umbilicus cephalad to the cyst. The specimen, which included the urachus, cyst and medial umbilical ligaments, was then separated from the bladder dome with or without the bladder cuff and removed intact. We reviewed the perioperative records to assess morbidity, recovery and outcome. RESULTS: All 4 procedures were completed successfully. No intraoperative or postoperative complications were reported at a mean followup of 15 months (range 2 to 24). Mean operative time was 180 minutes (range 150 to 210) and average hospital stay was 2.75 days (range 1 to 4). Pathological evaluation confirmed a benign urachal remnant in each case. All patients resumed normal activity within 2 weeks. CONCLUSIONS: To minimize the morbidity of radical excision the laparoscopic management of benign urachal remnants in adulthood is efficacious and our preferred method of management.  相似文献   
48.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
49.
Macrolides are widely used antibacterial agents. Although generally well tolerated, they have a number of important additional pharmacological effects, which can sometimes result in significant adverse reactions. This review focuses on three of these side effects: the prokinetic action associated with stimulation of motilin receptors, the proarrhythmic effect due to prolongation of the QT interval of the electrocardiogram and the potential for drug interactions due to inhibition of drug metabolising enzymes. For macrolides that have obtained marketing authorisation in Italy, United Kingdom or United States of America, we also considered whether these actions are properly reported in the approved summaries of the product characteristics and tried to provide strategies to identify patients at risk of significant side effects when macrolides are administered.  相似文献   
50.
Purpose: To evaluate whether or not an intermediate dose of preoperative external radiation therapy intensified by systemic chemotherapy could improve the tumor response, sphincter preservation, and tumor control.

Methods and Materials: Between March 1990 and December 1995, 83 consecutive patients with resectable extraperitoneal adenocarcinoma of the rectum were treated with preoperative chemoradiation: bolus i.v. mitomycin C (MMC), 10 mg/m2, Day 1 plus 24-h continuous infusion i.v. 5-fluorouracil (5FU) 1000 mg/m2, Days 1–4, and concurrent external beam radiotherapy (37.8 Gy). All but 2 patients had T3 disease. Surgery was performed 4–6 weeks after the end of chemoradiation.

Results: Total Grade 3–4 acute toxicity during chemoradiation was observed in 11 (13%) patients: hematological Grade 3 toxicity was recorded in 8 (10%) patients, and Grade 4 toxicity was recorded in 2 (2%) patients. Grade 3 diarrhea was seen in 2 (2%) patients. No patient had major skin or urological acute toxicity. Two patients had no surgery: 1 died before surgery from septic complications after Grade 4 hematological toxicity; 1 refused surgery and is still alive after 6 years. There was no postoperative mortality and the overall perioperative morbidity rate was 25%. The analysis of tumor response involved 81 patients. Overall, 9% [7] of 81 patients had a complete pathologic response. Comparing the stage at the diagnostic workup with the pathologic stage, tumor downstaging was observed in 46 (57%) patients. We had 7 (9%) pT0, 5 (6%) pT1, 33 (41%) pT2, and 36 (44%) pT3. Nodal status downstaging was detected in 46 patients (57%). No evidence of nodal involvement was observed in 59 patients (73%). The incidence of tumor response was affected significantly by the number of quarters of rectal circumference involved (p = 0.03) and, marginally, by the length of the tumor (p = 0.09). The distance between the lower pole of the tumor and the anorectal ring had no influence. Of the patients, 63 (78%) had a sphincter-saving surgical procedure. In 12 (44%) of 27 patients candidate for an APR, the sphincter was preserved, as it was in 19 (95%) of 20 probable candidates. Lengthening of the distance between the anorectal ring and the lower pole of the tumor > 20 mm was observed in 21 patients (26%). Of 63 patients, 4 (6%) had moderate soilage after the sphincter-saving procedure.

Conclusion: Preoperative combined modality therapy seems to afford some potential advantages in nonrandomized trials: patients are able to tolerate higher chemotherapy doses and they experience a lower acute toxicity. Tumor downstaging and resectability rates are high; sphincter preservation is feasible. Larger T3 tumors remained less influenced by this treatment; thus, taking into account the low toxicity rate recorded, a more aggressive schedule should be applied in these resectable tumors.  相似文献   

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