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We contrast two statistical methods: three-dimensional cluster analysis and statistical parametric mapping. We show that three-dimensional cluster analysis is based on a neurobiological theory of the regulation of blood flow and, unlike statistical parametric mapping, carries a minimum of assumptions that are tested. Statistical parametric mapping is a formal approach, which is based on a multitude of assumptions of which the majority have not been validated. We also demonstrate that in practice three-dimensional cluster analysis has a reasonable balance between sensitivity and the probability of false positives, giving high reproducibility with data on e.g. colour discrimination.  相似文献   
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The temporomandibular joint (TMS) lies at the skull base. Its bony roof forins part of the floor of the middle cranial fossa. It is bounded by the infratemporal fossa, external auditory canal, middle ear, and eustachian tube. When wide resection of tumors arising within the TMJ is necessary, skull base approaches permit complete resection with oncologically sound margins. Precise pathologic diagnosis can be difficult and extra care should be taken to ensure diagnostic accuracy. Outcomes are improved if attention and effort is directed to rehabilitation of the TMJ. Five such cases are presented and the literature is reviewed.  相似文献   
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The behavioral effects of the antidepressants nomifensine, diclofensine, bupropion, and imipramine were examined using a cocaine substitution drug self-administration procedure in baboons and a cocaine drug discrimination procedure in rats. Intravenous self-administration of the antidepressants was examined in baboons under conditions in which baseline responding was maintained by intravenous injections of cocaine HCl (0.32 mg/kg/injection). Drug was available under a fixed-ratio 80-response or 160-response schedule of intravenous injection. Each drug injection was followed by a 3-h time-out allowing a maximum of eight injections per day. The antidepressants or their vehicles were substituted for cocaine for a period of 15 days, followed by a return to the cocaine baseline. Nomifensine, diclofensine, and bupropion all maintained self-administration behavior at levels above those maintained by their respective vehicles. Some doses of nomifensine, diclofensine, and bupropion maintained levels of behavior similar to those maintained under baseline cocaine conditions. High doses of imipramine maintained levels of behavior above those maintained by its vehicle, but the amount of behavior maintained under these conditions was extremely small. In a second experiment rats were trained to discriminate 32 µmol/kg cocaine (IP 10 min presession) from no drug in a two-lever food reinforced drug discrimination procedure in which responding on one lever was reinforced following ten consecutive responses when the session was preceded by cocaine administration, while responding on the other lever was similarly reinforced in the absence of cocaine pretreatment. Cocaine, nomifensine, diclofensine, and bupropion all dose-dependently occasioned cocaine-appropriate responding. Imipramine did not occasion cocaine-appropriate responding over a range of behaviorally active doses.  相似文献   
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Conventional radiographs do not always make it possible to confirm a diagnosis of ischemic necrosis of the lunate in the early stages of disease. For these doubtful cases MRI is justifiable in addition, to diagnose or to rule out ischemic necrosis of the lunate.  相似文献   
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BACKGROUND: The intent of this study was to ascertain the adequacy of delivery of enteral nutrition (EN) to critically ill adult multiple trauma patients and to identify potential detrimental factors that affect EN delivery. METHODS: Retrospective observational study. Trauma intensive care unit (TICU) in a university-affiliated hospital. Adult patients (>/=18 years of age) admitted to the TICU who received enteral feeding. RESULTS: Fifty-six adult patients were enrolled for study. Patients received, on average, 67% +/- 19% of what was prescribed for 5.7 +/- 2.0 days. A total of 222 occurrences for temporary discontinuation of tube feeding were identified. Gastrointestinal intolerance, as defined by a gastric residual volume of >150 mL, abdominal pain, or >3 liquid stools per day, accounted for only 11% of the occurrences for discontinuation of feeding. Surgery (27%) and diagnostic procedures (15%) represented the majority of reasons for inadequate nutrient delivery. Minor factors for EN interruptions were mechanical feeding tube problems (8%), pharmacy delivery delay (4%), and miscellaneous factors (3%). Multiple and unknown reasons contributed to 14% and 18% of the occurrences, respectively. CONCLUSIONS: Surgery and diagnostic procedures accounted for the largest factor in enteral feeding discontinuations in our critically ill trauma patients. Gastrointestinal intolerance contributed a minor role in the temporary discontinuation of enteral feeding.  相似文献   
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Assessment of disease activity in rheumatoid arthritis with (18)F-FDG PET.   总被引:5,自引:0,他引:5  
The aim of this study was to assess synovitis by (18)F-FDG PET in an individual joint analysis and in a global analysis of rheumatoid arthritis (RA) disease activity and to compare (18)F-FDG PET parameters with clinical, biologic, and sonographic (US) rheumatoid parameters. METHODS: Three hundred fifty-six joints were assessed in 21 patients with active RA: the knees in all subjects and either wrists as well as metacarpophalangeal and proximal interphalangeal joints in 13 patients, or ankles and the first metatarsophalangeal joints in the remaining 8 patients. PET analysis consisted of a visual identification of (18)F-FDG uptake in the synovium and measurements of standardized uptake values (SUVs). Independent assessors performed the clinical and US examinations. RESULTS: PET positivity was found in 63% of joints, whereas 75%, 79%, and 56% were positive for swelling, tenderness, and US analysis, respectively. Both the rate of PET-positive joints and the SUV increased with the number of positive parameters present (swelling, tenderness, US positivity) and with the synovial thickness. The mean SUV was significantly higher in joints where a power Doppler signal was found. In a global PET analysis, the number of PET-positive joints and the cumulative SUV were significantly correlated with the swollen and tender joint counts, the patient and physician global assessments, the erythrocyte sedimentation rate and C-reactive protein serum levels, the disease activity score and the simplified disease activity index, the number of US-positive joints, and the cumulative synovial thickness. CONCLUSION: (18)F-FDG PET is a unique imaging technique that can assess the metabolic activity of synovitis and measure the disease activity in RA.  相似文献   
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Zusammenfassung Wir berichten fiber die Doppler-sonographischen Ergebnisse bei 33 Patienten mit einer Anastomose zwischen der A. temporalis superficialis and der A. cerebri media. Die Indikation zur Bypass-Operation beinhaltete rezidivierende TIA oder ein kurz zuvor erworbenes leichtes neurologisches Defizit bei angiographischem Nachweis einseitiger oder beidseitiger tiefer Obliterationen der A. carotis interna und hochgradiger Stenosen oder Verschlüsse im distalen Abschnitt der A. carotis interna bzw. im proximalen Abschnitt der A. cerebri media. Die Funktionsfahigkeit der Anastomose wurde überpriift durch die Berechnung der modifizier ten Pourcelot-Indices (relative enddiastolische Strömungsgeschwindigkeit) der A. temporalis superficialis praeauriculär und am Bohrlochrand Bowie durch den EinfluB der intermittierenden Kompression des den Bypass-versorgenden Gefäßes auf den modifizierten Pourcelot-Index der ipsilateralen A. carotis communis. Bei allen Patienten mit funktionsfahigen Anastomosen, definiert durch einen modifizierten Pourcelot-Index von zumindest 0,20 am Bohrlochrand, kam es zu einer Reduktion dieses Parameters um durchschnittlich 0,08 an der A. carotis communis bei kurzfristiger Kompression des den Bypass-versorgenden Astes. Bei den 18 Patienten mit unilateraler Obliteration der A. carotis interna war der Bypass über-wiegend dann funktionsfähig, wenn die summierten modifizierten Pourcelot-Indices der verbliebenen hirnversorgenden Gefäße um zumindest 10% gegenüber einem vergleichbaren Normalkollektiv reduziert waren. Das Vorhandensein bzw. das Fehlen von Ophthalmica-Kollateralen hatte dabei keinen Einfluß auf den Prozentsatz der funktionsfahigen Anastomosen in diesen Untergruppen. Bei den vier Patienten mit bilateraler Obliteration der A. carotis interna war die angelegte Anastomose in jedem Fall funktionsfähig, während die Hälfte der Patienten mit Stenosen and Verschlüssen im distalen Abschnitt der Carotisstrombahn nur eine ungeniigende Bypass-Funktion zeigten. Die zwei Patienten mit einer Mediahauptstammstenose bzw. -obliteration hatten Indices von 0,45 bzw. 0,46 am Bohrlochrand als Hinweis auf die Funktionstüchtigkeit. Wir Bind der Auffassung, daß man mittels Doppler-sonographischer Kriterien die Funktionsfahigkeit einer Temporalis superficialis-Cerebri media-Anastomose überprüfen kann. Der praeoperativ berechnete summierte modifizierte Pourcelot-Index der verbliebenen hirnversorgenden Arterien kann zumindest bei uni- and bilateraler Internaobliteration als zusatzlicher Parameter herangezogen werden, um die Indikation zur Bypass-Operation zu klären.  相似文献   
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