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101.
In previous functional neuroimaging studies, left anterior temporal and temporal-parietal areas responded more strongly to sentences than to randomly ordered lists of words. The smaller response for word lists could be explained by either (1) less activation of syntactic processes due to the absence of syntactic structure in the random word lists or (2) less activation of semantic processes resulting from failure to combine the content words into a global meaning. To test these two explanations, we conducted a functional magnetic resonance imaging study in which word order and combinatorial word meaning were independently manipulated during auditory comprehension. Subjects heard six different stimuli: normal sentences, semantically incongruent sentences in which content words were randomly replaced with other content words, pseudoword sentences, and versions of these three sentence types in which word order was randomized to remove syntactic structure. Effects of syntactic structure (greater activation to sentences than to word lists) were observed in the left anterior superior temporal sulcus and left angular gyrus. Semantic effects (greater activation to semantically congruent stimuli than either incongruent or pseudoword stimuli) were seen in widespread, bilateral temporal lobe areas and the angular gyrus. Of the two regions that responded to syntactic structure, the angular gyrus showed a greater response to semantic structure, suggesting that reduced activation for word lists in this area is related to a disruption in semantic processing. The anterior temporal lobe, on the other hand, was relatively insensitive to manipulations of semantic structure, suggesting that syntactic information plays a greater role in driving activation in this area.  相似文献   
102.
OBJECTIVE: Data characterizing bipolar disorder in older people are scarce, particularly on functional status. We evaluated health-related quality of life and functioning (HRQoLF) among older outpatients with bipolar disorder as well as the relationship of HRQoLF to bipolar illness characteristics. METHOD: We compared community-dwelling middle-aged and older adults (age range, 45 to 85 years) with bipolar disorder (N=54; mean age=57.6 years), schizophrenia (N=55; mean age=58.5 years), or no psychiatric illnesses (N=38; mean age=64.7 years) on indicators of objective functioning (e.g., education, occupational attainment, medical comorbidity) and health status (e.g., Quality of Well-Being scale [QWB] and the Medical Outcomes Study-Short Form Health Survey [SF-36]). Within the group with bipolar disorder, we examined the relationship between HRQoLF and clinical variables (e.g., phase and duration of illness, psychotic symptoms, cognitive functioning). RESULTS: Patients with bipolar disorder were similar in educational and occupational attainment to the normal comparison group, but they obtained lower scores on the QWB and SF-36 (with large effect sizes). Compared with schizophrenia, bipolar disorder was associated with better educational and work histories but similar QWB and SF-36 scores and more medical comorbidity. Patients in remission from bipolar disorder had QWB scores that were worse than those of normal comparison subjects. Greater severity of psychotic and depressive symptoms and cognitive impairment were associated with lower HRQoLF. CONCLUSIONS: Bipolar disorder was associated with substantial disability in this sample of older adults, similar in severity to schizophrenia. Remission of bipolar disorder was associated with significant but incomplete improvement in functioning, whereas psychotic and depressive symptoms and cognitive impairment seemed to contribute to lower HRQoLF.  相似文献   
103.
Even with the availability of novel and efficacious antihypertensive agents, an insufficient number of hypertensive patients achieve their desired blood pressure (BP) target. This failure is partly due to the fact that many patients do not strictly adhere to their drug therapy and/or they report the presence of adverse effects. Traditionally, monotherapy is used as first-line treatment to achieve BP targets; however, when this fails, combination therapy is then required. In light of the need to attain BP goals, combination therapy (especially fixed-dose) is currently recommended. The main advantages of combination therapy over monotherapy are not only that of reduced dose, improved efficacy and reduced adverse effects, but also of target protection and reduced cardiovascular (CV) risk. Therefore, the development of single-administration drug combinations should also improve patient adherence to therapy and therefore help in achieving BP control. Among the various combinations available, calcium channel blockers (CCBs) and angiotensin-converting enzyme (ACE) inhibitors have been proven to be extremely effective, while also displaying good tolerability. Individually, both the third-generation CCB lercanidipine and the ACE inhibitor enalapril are effective antihypertensive agents. In addition, both of these agents also show other beneficial effects when administered as monotherapy. Of particular importance is the fact that when lercanidipine plus enalapril are administered in combination, they show synergism, thus providing added efficacy with reduced side effects. The present report provides an overview of the main clinical studies examining lercanidipine and enalapril administered as monotherapy, with particular focus on the potential renoprotective effects afforded by the fixed-dose combination lercanidipine-enalapril.  相似文献   
104.

Background  

The Association of Coloproctology of Great Britain and Ireland (ACPGBI) risk-adjustment model for colorectal cancer surgery has been recently revised. The aim of the present study was to compare the performance of the revised ACPGBI model, the original ACPGBI model, P-POSSUM, and CR-POSSUM, in the prediction of operative mortality after resection of colorectal cancer.  相似文献   
105.
106.
Background: Propofol, sevoflurane, and desflurane may cause hemodynamic compromise during anesthesia and critical care management. The aim of the study was to compare these anesthetics during increased dose and recovery to maintenance level.

Methods: Anesthetized, open-chest New Zealand White rabbits were used to acquire dose-response curves with sevoflurane, desflurane, and propofol, followed by reduction to baseline infusion. Simultaneous high-fidelity left ventricular pressure and volume data were acquired during caval occlusion with a dual-field conductance catheter inserted via an apical stab. The preload recruitable stroke work and the end-diastolic pressure-volume relationship were used as the primary measures of contractility and diastolic function.

Results: The time-matched controls were stable over time. Propofol and desflurane but not sevoflurane caused dose-dependent reductions in myocardial contractility, although sevoflurane reduced contractility more at 1 minimal alveolar concentration. All anesthetics reduced mean arterial pressure, and significant recovery occurred for sevoflurane and desflurane but not for propofol. The end-diastolic pressure-volume relationship was increased by sevoflurane. Ejection fraction decreased with sevoflurane only. All anesthetics caused dose-dependent vasodilation, with recovery for desflurane and sevoflurane but not propofol. Heart rate was decreased with propofol without significant recovery. Propofol plasma concentrations remained elevated after dose return to baseline infusion rate, suggestive of distribution compartment saturation.  相似文献   

107.
BACKGROUND CONTEXT: Injuries at the cervicothoracic junction are common in patients with ankylosing spondylitis. These injuries present challenges for both initial and follow-up imagings. PURPOSE: To describe a case of a patient with ankylosing spondylitis who was treated with laminectomy and a cervicothoracic orthosis for a spinal epidural hematoma after a nondisplaced fracture at the cervicothoracic junction and to discuss the merits of stand-up magnetic resonance imaging (MRI) for follow-up evaluation of this type of injury. STUDY DESIGN/SETTING: Case report. METHODS: Clinical data of a patient with ankylosing spondylitis who sustained a nondisplaced C7 fracture are presented, followed by a detailed review of the literature concerning imaging techniques available for the evaluation of cervical spine trauma in this patient population. RESULTS: The patient was treated with emergent laminectomy and evacuation of the epidural hematoma, followed by definitive management in a cervicothoracic orthosis secondary to medical comorbidities. The patient was then successfully followed postoperatively with stand-up MRI because conventional imaging techniques could not adequately image the injury level in an upright position. CONCLUSIONS: Cervicothoracic injuries are common in patients with ankylosing spondylitis and may be difficult to follow with conventional imaging techniques. Stand-up MRI is a relatively new modality that may offer significant advantages over conventional imaging because of the ability to evaluate the cervicothoracic junction in a more functional position and the lack of a confining space such as that found in standard MRI units.  相似文献   
108.
Chronic tubulo-interstitial disease, an important cause of end-stage renal disease, often results from the combined effects of a disturbed urinary outflow tract and urinary tract infection. Acute unilateral ureteral obstruction in rats rapidly induces foci of medullary necrosis, confined to the region of the papilla and fornices. This injury may provide a nidus for bacterial invasion and may invoke reactive and regenerative changes, ultimately leading to chronic pyelonephritis and tubulo-interstitial nephropathy. To explore this possibility, adult rats underwent renal morphological evaluation 2–7 days following transient 24-h unilateral ureteral obstruction. In some experiments the bladder was inoculated with bacteria (108–109 cfu/ml Escherichia coli in 0.5 ml) after release of ureteral obstruction, with subsequent cultures obtained from the pelvis of both kidneys and from the urinary bladder. Morphologic evaluation of perfusion-fixed kidneys, 2–7 days after the release of 24-h ureteral obstruction disclosed papillary necrosis, urothelial proliferation, marked inner-stripe interstitial expansion, and fibrosis and proximal tubular (S3) dilatation. The lateral (perihilar region) was predominantly affected, with lesions spreading from the fornices. There was some progression of interstitial fibrosis during the postobstructive time course or following more prolonged ureteral obstruction. By contrast, infection hardly contributed to the tubulointerstitial changes. In rats subjected to infection, cultures were positive in all 15 postobstructive kidneys, as opposed to five contralateral kidneys (P < 0.0001). Viable counts from the postobstructive kidney were also higher than those from the contralateral side (79,000 ± 12,000 vs 2900 ± 1600 cfu/ml, mean ± SEM, P < 0.0001), and were comparable to those obtained from the bladder (77,000 ± 13,000 cfu/ml). We conclude that transient ureteral obstruction predisposes to ascending pyelonephritis and to tubulointerstitial disease. This vulnerability may relate to altered urodynamics and medullary tissue destruction. Received: 28 December 1999 / Accepted: 28 September 2000  相似文献   
109.
Aim: The prognosis of patients with disseminated colorectal carcinoma is poor except for those with single organ pulmonary or hepatic metastases. The objective of the present study was to evaluate the result of pulmonary metastasectomy for colorectal secondary and to identify the prognostic factors. Methods: This was a retrospective study of 80 patients who had pulmonary metastasectomy for pulmonary secondary from colorectal carcinoma in Queen Elizabeth Hospital, Hong Kong. Results: The overall 5‐year and 10‐year survival rates of the entire cohort were 42.5% and 35.5%, respectively. High premetastasectomy carcinoembryonic antigen (> 20 μg/dL), short disease‐free interval (< 12 months) and incomplete resection were the independent prognostic factors. Neither the characteristics of the primary colorectal tumour nor the number of metastatic nodules had a significant contribution to the long‐term survival. Six patients underwent second pulmonary metastasectomy and three were still free from tumour recurrence after the second operation. Conclusion: Patients with pulmonary metastases from colorectal carcinoma would benefit from pulmonary metastasectomy. High premetastasectomy carcinoembryonic antigen and short disease‐free interval were negative predictive factors for survival. Long‐term follow‐up study is required, as recurrence can occur more than 5 years after pulmonary metastasectomy. Also, whether the survival benefit is due to surgical treatment effect or lead‐time bias remains undecided.  相似文献   
110.
Pediatric robotic surgery: lessons from a clinical experience   总被引:1,自引:0,他引:1  
PURPOSE: Robotic surgery may improve minimally invasive surgery at high magnification by tremor filtration, motion-scaling, and improved dexterity with the provision of a wrist at the end of the robotic instrument. MATERIALS AND METHODS: We chose the Zeus Microwrist robotic surgical system as more applicable to small children than the competing da Vinci surgical system. We attempted 57 surgical procedures and completed 54. RESULTS: Completed procedures included Nissen fundoplication (n = 25), cholecystectomy (n = 18), Heller myotomy (n = 2), splenectomy (n = 2), Morgagni hernia repair (n = 2), and single cases of complex pyloroplasty in the chest, bowel resection, left Bochdalek congenital diaphragmatic hernia repair, esophageal atresia and tracheoesophageal fistula repair, and choledochal cyst excision. There were no complications related to the use of the robot. The mean time for the surgeon at the console using the robot was 117 +/- 39 minutes for Nissen fundoplication, and the total operating room time was 250 +/- 60 minutes. Surgeons found dissection, suturing, and knot tying easier than with conventional laparoscopy. None of the surgeons thought the lack of touch feedback (haptics) was crucial. CONCLUSION: Robotic surgery offers increased dexterity to the pediatric minimally invasive surgeon, but procedures require more time, and there is no defined patient benefit. The fact that robotic surgery digitalizes minimally invasive surgery creates exciting possibilities for training surgeons, planning operations, and performing surgery at great distances from the operator.  相似文献   
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