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51.
To examine the neurophysiological and cognitive characteristics of language disorder in schizophrenia, the N400 component and late positive component (LPC) of event-related potentials (ERPs) were investigated in medicated schizophrenic patients and health comparison subjects. The subjects were required to indicate whether Japanese sentence completions were semantically congruous or incongruous. The ERPs for the range of 300-500 ms to the incongruous completions contained a more negative component (N400), followed by LPC, which was inversely more positive for the incongruous than congruous condition. The N400 effect and the mean amplitude of the LPC were reduced in the patients. The attenuated N400 effect in schizophrenics mainly originated from an enhanced negativity for the congruous completions, suggesting that the use of context is poor in schizophrenia. 相似文献
52.
Toshiharu Kasaba Gotaro Yoshikawa Tomoko Seguchi Mayumi Takasaki 《Journal canadien d'anesthésie》1996,43(12):1211-1215
Purpose
To determine the extent of enhanced blockade by the combined use of epidural fentanyl and mepivacaine. We compared the onset of hypoalgesia, analgesia and the threshold of pressure pain.Methods
Thirty patients were randomly divided into three groups. The fentanyl group received 10 ml saline containing 0.1 mg fentanyl, mepivacaine group received 10 ml mepivacaine 1% and a mixed group received 10 ml mepivacaine 1% with 0.1 mg fentanyl. All solutions, without epinephrine, were injected through an epidural catheter at T5–6 to T6–7. The change in sensation, loss of pin-prick and pain threshold sensation, measured by pressure algometer, were assessed at 2.5-min intervals for 15 min at the T4 dermatome. Spread of analgesia was determined at 15 min.Results
Loss of pinprick was more rapid in the mixed, 11.0 ± 2.7 (SD) min, than in the mepivacaine group, 15.0 ± 2.9 min, (P < 0.05), although there was no difference in change of sensation. Pressure pain threshold increased with time in the mepivacaine (P < 0.05) and mixed (P < 0.05) groups. It was higher in the mixed than in the fentanyl and mepivacaine groups at 5, 7.5 and 10 min (P < 0.05). The lower level of analgesia was lower in the mixed than in the mepivacaine groups (P < 0.05). Blood pressure was unchanged in the three groups, but heart rate decreased at 7.5, 10, 12.5, and 15 min in the mepivacaine and mixed groups (P < 0.05).Conclusions
The addition of fentanyl to mepivacaine accelerates the onset of analgesia and enhances the analgesic effect of epidural block. 相似文献53.
T. Morioka T. Matsushima K. Ikezaki S. Nagata M. Ohta K. Hasuo M. Fukui 《Neuroradiology》1993,35(6):462-465
Two cases of intracranial adenoid cystic carcinoma mimicking meningioma are reported. In one, MRI showed not only a homogeneously enhancing extra-axial tumour attached to the dura mater of the posterior cranial fossa, but also surrounding dural enhancement, the dural tail sign. In the second, CT demonstrated a well-demarcated enhancing extra-axial tumour, indistinguishable from a sphenoid ridge meningioma extending into the orbit. The neuroradiological features of intracranial adenoid cystic carcinoma may thus closely resemble those of meningioma. 相似文献
54.
1. To elucidate the neural mechanisms responsible for coordinating undulatory locomotor movements, the intersegmental phase lag was analyzed from ventral roots along the spinal cord during fictive swimming. It was induced by bath application of N-methyl-D-aspartate (NMDA) in in vitro preparations of lamprey spinal cord, while the excitability of different segments were modified. The phase lag between consecutive segments during normal forward swimming is 1% of the cycle duration in a broad range of values. Rostral segments are activated before more caudal ones. 2. Under control conditions, whole preparations (12-24 segment long; n = 22) were perfused with NMDA solutions of the same concentration (100-150 microM). The intersegmental phase lag values varied in a continuous range with a single peak around a median value of forward +0.74% per segment (range: forward +2.23% to backward -0.97%). 3. To examine whether excitability differences along the spinal cord could modify the intersegmental phase lag, different levels of excitatory amino acids (NMDA) were applied to spinal cord preparations positioned in a partitioned chamber. Different portions of the cord could be perfused separately by NMDA solutions of different concentrations (50-150 microM). If rostral segments were perfused with the higher NMDA solution, the lag was inevitably in the forward direction. Conversely, if the caudal portion was perfused with the higher NMDA solution, caudally located ventral roots became activated before the rostral ventral roots in a caudorostral succession, thus reversing the direction of the fictive swimming wave to propagate as during backward swimming. If the middle portion was perfused by the highest NMDA solution, this portion instead became leading, and the activity propagated from this point in both the rostral and the caudal directions. The portion located in the pool with highest NMDA concentration always gave rise to a "leading" segment. 4. When a portion of the preparation was perfused with an NMDA solution of a high concentration (75-150 microM), the cycle duration was close to that recorded when the whole preparation was perfused with the same high NMDA solution. The ensemble cycle duration is, therefore, largely determined by the leading segment. 5. The phase lag changes were not restricted to the region around the barrier separating pools with different NMDA solutions.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
55.
Hideki Nagano Shigekazu Ohyama Yoshihiro Sakamoto Keiichiro Ohta Toshiharu Yamaguchi Tetsuichiro Muto Akio Yamaguchi 《Gastric cancer》2004,7(1):54-59
Background Pylorus-preserving gastrectomy (PPG) and transverse gastrectomy (TrG) have been accepted as function-preserving procedures for node-negative early gastric cancer. It is believed that a better quality of life is guaranteed after PPG or TrG compared to that after distal subtotal gastrectomy (DSG) with Billroth type-I reconstruction. However, objective evaluations of the gastric remnant following gastrectomy have not been widely reported, and the real advantages and disadvantages of PPG or TrG over DSG remain unclear. Moreover, the risk of secondary cancer after PPG or TrG is uncertain.Methods Between 1991 and 2000, 834 DSGs were carried out in our institute for preoperatively diagnosed patients with early gastric cancer. The degree of residual gastritis and the amount of diet residue in the gastric remnant were evaluated by annual gastrointestinal endoscopic investigations prospectively for 72 patients after PPG, 95 patients after TrG, and 60 patients after DSG. These analyses were performed using the RGB classification (residue, gastritis, bile). The incidence of disease greater than or equal to grade 2 was calculated, and the time trends of the incidence for each procedure were also studied for 3 years after gastrectomy. In addition, secondary cancer cases in the gastric remnant mucosa were checked for each procedure during this period, and the incidence of secondary cancer after each operation was calculated.Results The incidence of gastritis, of grade 2 or more, found in the gastric remnant was significantly lower after PPG (1.4%) and TrG (2.1%) than after DSG (43.3%). However, the incidence of moderate or greater residue in the gastric remnant, grade 2 or more, was significantly higher after PPG (45.8%) and TrG (40.0%) than after DSG (11.7%). The analysis of time trends of gastritis and diet residue reflected the significant advantage or disadvantage for each procedure 1 year after surgery. The analysis also included these factors without consideration of elapsed time following surgery. Two patients after PPG (2.8%) and three patients after TrG (3.2%) developed secondary cancer in the gastric remnant. No DSG-treated patient showed new cancer genesis in the remaining stomach.Conclusion PPG and TrG have the advantage over DSG in preventing postoperative gastritis in the gastric remnant. On the other hand, moderate or greater diet residue in the gastric remnant is more common after PPG or TrG than after DSG. For the risk of carcinogenesis in the remnant gastric mucosa, we could not conclude that there was any apparent difference between these range-limited gastrectomies and conventional DSG. Further study is necessary to determine the significant advantages and disadvantages of using PPG or TrG. 相似文献
56.
Toshiharu Miyake Tohru Shinohara Yoshihide Nakamura Tsuyoshi Fukuda Hiroshi Tasato Keiko Toyohara Yuko Tanihira 《Pediatrics international》2004,46(2):135-140
BACKGROUND: This study evaluates the incidence and timing of spontaneous closure (SC) of ventricular septal defect (VSD) using Doppler color flow mapping. METHODS: A total of 225 infants (mean age 30 days) were diagnosed with uncomplicated VSD: 31 (14%) subpulmonary VSD, 159 (70%) perimembranous, and 35 (16%) muscular. The patients were divided into two groups according to the presence or absence of congestive heart failure (CHF). SC was confirmed with color Doppler. RESULTS: Surgical closure was performed in 59 patients (26%). SC occurred in 107 patients (48%); three (10%) of 31 with subpulmonary VSD, 75 (47%) of 159 with perimembranous VSD, and 29 (83%) of 35 with a muscular VSD. Average age at SC was 19 months. In three SC patients with a subpulmonary VSD, there was no aortic valve prolapse and no aortic regurgitation. SC occurred in 96% of SC patients with a perimembranous VSD by the age of 6 years, and in 93% of those with a muscular VSD by the age of 3 years. In patients without CHF, the rate of SC was 72%; 23% in subpulmonary VSD, 74% in perimembranous, and 85% in muscular. SC occurred in only 23% of patients with a perimembranous VSD with CHF. Mean age at the final examination was 6.9 years in 59 patients with a VSD remaining open, and 63% of patients with a perimembranous VSD remaining open had an aneurysm of the ventricular membranous septum. CONCLUSIONS: The SC rate of VSD by mean age of 6.9 years was 48%, but it was 72% in patients without CHF. In patients with CHF, SC was seen only in patients with a perimembranous VSD. The rate of SC was 10% in subpulmonary VSD. The authors contend that SC probably occurred by growth of muscular septum surrounding VSD. Muscular VSD spontaneously closed earlier than perimembranous VSD. 相似文献
57.
Atsushi Yoshida Takashi Sugiyama Tsutomu Tabata Toshiharu Okugawa Norimasa Sagawa 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(3):109-114
The usefulness of the vascular ultrasound in the field of obstetrics is now well recognized. Intima-media thickness (IMT) and elastic property of the common carotid artery are affected by pregnancy and vary with complications. Flow-mediated vasodilation (FMD) of the brachial artery reflects the vascular endothelial function and is reported to be useful in the management of complicated pregnancy, especially pre-eclampsia. For the screening of deep vein thrombosis of the lower extremities in the perinatal period, compression ultrasonography (CUS) is useful. 相似文献
58.
We investigated whether the species difference in the biliary excretion activity of some Mrp2 substrates was attributable to the intrinsic transport potential or the expression level of Mrp2, especially in rat and dog. Dog Mrp2 cDNA was isolated from beagle dog liver, and a vesicle transport study was performed using recombinant rat and dog Mrp2 expressed in insect Sf9 cells. The ATP-dependent transport of 17beta-estradiol 17-(beta-D-glucuronide) ([3H]E(2)17betaG) and leukotriene C4 ([3H]LTC4), normalized by the absolute protein expression level, was similar in both Mrp2s. The Mrp2 protein expression in dog liver was only 10% of that in rat liver and was comparable with the reported difference in the biliary excretion clearance of temocaprilat as Mrp2 substrate. In contrast to LTC4, unique transport kinetics for E(2)17betaG were evident in dog Mrp2. In addition to the high-affinity site with a K(m) value of 3.25 +/- 0.10 microM, which is similar to that in rat Mrp2 (4.81 +/- 1.21 microM), dog Mrp2 has an additional low-affinity site (>75 microM), which makes a major contribution to the transport of E(2)17betaG (65% of the total transport capacity at tracer concentration). In summary, the difference in the biliary excretion activity of Mrp2 substrates between rat and dog depends on the Mrp2 protein expression level rather than the intrinsic transport activity of the transporter molecules. The unique transport properties of glucuronide conjugates by dog Mrp2 may lead to the species difference involving the drug-drug interaction or drug-induced hyperbilirubinemia on the bile canalicular membrane. 相似文献
59.
Akira Kasuya Jun‐ichi Sakabe Reiko Kageyama Shigeki Ikeya Toshiharu Fujiyama Yoshiki Tokura 《The Journal of dermatology》2014,41(6):542-544
The polymerase chain reaction (PCR) assay for varicella zoster virus (VZV), herpes simplex virus (HSV)‐1 and HSV‐2 is available for use. Sometimes the differential diagnosis of the generalized herpes zoster (HZ), HSV1/2, and drug eruption is difficult. We report a case of HZ followed by the vesicular erythema multiforme (EM)‐like lesion. In this case the use of PCR was of great assistance. A 78‐year‐old Japanese man without any significant previous history of disease was admitted to our hospital complaining of zosteriform vesicle on an erythematous base from his right shoulder to the upper arm. We diagnosed him with HZ at the level of right Th2. In spite of the prompt start of antiviral therapy, a secondary new vesiculous erythema developed on his trunk. Clinically, it was quite difficult to differentiate the lesion from the generalized HZ. Rapid PCR assay of effusion and crust for VZV was performed. A PCR assay of VZV was positive for the crust taken from the primary lesion, while it was negative for the effusion and crust of the secondary widespread lesion. We diagnosed the secondary widespread lesion as an EM‐type drug eruption induced by acyclovir, or an EM associated with herpes zoster. We then stopped the use of acyclovir and applied steroid ointment of a very strong class for the secondary lesions, which improved after a few days. A PCR assay for VZV was useful for ruling out the generalized HZ in our case with secondary developed vesiculous lesions. 相似文献
60.