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91.
92.
PURPOSE: To compare the accuracy of thin-section CT, conventional static MR imaging (conventional MRI), and breathing dynamic echo planar magnetic resonance imaging (BDEPI) in evaluating lung cancer invasion to the chest wall. MATERIALS AND METHODS: Thin-section CT, conventional MRI, and BDEPI were performed preoperatively in 20 patients suspected of having primary lung cancers adjacent to the chest wall on conventional CT. The results of imaging findings were compared with those of surgical and histopathological findings. RESULTS: All patients were confirmed to have no chest wall invasion after surgery. By thin-section CT, 10 of 20 patients were correctly diagnosed as having no chest wall invasion (50% specificity). Two of the 20 patients were incorrectly diagnosed as having chest wall invasion by conventional MRI and BDEPI (90% specificity). CONCLUSION: When chest wall invasion is suspected on CT scans, static and breathing dynamic MRI are recommended to avoid false positive interpretations.  相似文献   
93.
Yamada K  Wada E  Wada K 《Brain research》2000,870(1-2):20-26
Previously, we generated gastrin-releasing peptide receptor null mutant mice (GRP-R-deficient mice), and found that these animals displayed increased non-aggressive social responses in an ordinary social interaction test using a resident-intruder method. In the present study, we examined in more detail the social behaviors of GRP-R-deficient male mice. In social interaction tests, GRP-R-deficient mice showed more social responses, such as sniffing and nosing, relative to wild-type mice, and similar results were obtained whether GRP-R-deficient mice served as intruders or residents. In the same way, they showed more contact behaviors toward an anesthetized conspecific, and less locomotor activity than wild-type mice in a social investigation test toward an anesthetized male mouse. Since olfactory systems play important roles in the social behavior of rodents, olfactory preference tests were conducted in order to evaluate the olfactory properties of GRP-R-deficient mice. The results suggest that no differences exist between wild-type mice and GRP-R-deficient mice in the preference between a novel sawdust odor and their own odor, or that of other male mice. However, GRP-R-deficient mice preferred the odor of other male mice to their own, in contrast to wild-type mice. Furthermore, the preferences of GRP-R-deficient and wild-type mice were not disrupted by intraperitoneal infusion of diazepam (1.5 mg/kg). These results indicate that neither the motion, nor the behavior of conspecifics, nor reduced anxiety lead to the increased non-aggressive social responses and/or social investigatory behaviors in GRP-R-deficient mice. Rather, these latter behaviors may be a consequence of altered cognition of conspecific odors in the mutant mice.  相似文献   
94.
Subcortical meningioma, which has been reported as meningioma without dural attachment, a cerebral subcortical lesion, is extremely rare. Very few findings of radiological examination of subcortical meningioma have been described. Pre-operative differentiation of this lesion is generally difficult. We characterize the peritum oural oedema adjacent to the meningioma in this region, and we suggest that radiological findings of peritum oural oedema contribute to differential diagnosis of subcortical meningiomas.  相似文献   
95.
We investigated the effect of propofol anesthesia on the level of interstitial dopamine in vivo awake free moving and anesthetized rats brain striatum using microdialysis techniques. Rats were implanted a microdialysis probe to right striatum of the brain and administered intravenously 20 mg.kg-1 of propofol for induction and followed by continuous infusion at 12.5, 25 and 50 mg.kg-1.hr-1 up to 1 hour. The microdialysis probe was perfused with artificial cerebrospinal fluid and dialysates from the probe were determined every 20 minutes by high performance liquid chromatography and electrochemical detection. Propofol anesthesia reduced the amount of dopamine derived from dialysate, but no prolonged increases of dopamine metabolites were observed, as we demonstrated in previous investigation for halothane, isoflurane or sevoflurane anesthesia. We hypothesize that the characteristics of propofol anesthesia for dopamine and its metabolites might contribute to low incidence of postoperative nausea and vomiting in its clinical use.  相似文献   
96.
Fulminant type 1 diabetes is characterized by a rapid progression of insulin deficiency triggered by viral infection. Here, we report a case of a 45‐year‐old Japanese woman with fulminant type 1 diabetes that developed 8 days after receiving messenger ribonucleic acid vaccine against severe acute respiratory syndrome coronavirus 2. She had been healthy and had no symptoms suggestive of viral infection before the vaccination. Laboratory tests showed exhaustion of insulin secretion and negative results for islet autoantibodies. Human leukocyte antigen genotype analysis showed the DRB1*04:05 and DQB1*04:01 alleles. This is the first case report of new‐onset fulminant type 1 diabetes after severe acute respiratory syndrome coronavirus 2 vaccination, and suggests that a severe acute respiratory syndrome coronavirus 2 vaccine might trigger the onset of fulminant type 1 diabetes in susceptible individuals. However, a causal relationship remains to be identified, and further studies are required to determine the incidence of such cases.  相似文献   
97.
The dosimetric effect of set-up error in boron neutron capture therapy (BNCT) for head and neck cancer remains unclear. In this study, we analyzed the tendency of dose error by treatment location when simulating the set-up error of patients. We also determined the tolerance level of the set-up error in BNCT for head and neck cancer. As a method, the distal direction was shifted with an interval of 2.5 mm, from 0.0 mm to +20.0 mm and compared with the dose at the reference position. Similarly, the horizontal direction and vertical direction were shifted, with an interval of 5.0 mm, from −20.0 mm to +20.0 mm. In addition, cases with 3.0 mm and 5.0 mm simultaneous shifts in all directions were analyzed as the worst-case scenario. The dose metrics of the minimum dose of the tumor and the maximum dose of the mucosa were evaluated. From unidirectional set-up error analysis, in most cases, the set-up errors with dose errors within ±5% were Δdistal < +2.5 mm, Δhorizontal < ±5.0 mm and Δvertical < ±5.0 mm. In the simulation of 3.0 mm shifts in all directions, the errors in the minimum tumor dose and maximum mucosal dose were −3.6% ±1.4% (range, −5.4% to −0.6%) and 2% ±1.4% (range, 0.4% to 4.5%), respectively. From these results, if the set-up error was within ±3.0 mm in each direction, the dose errors of the tumor and mucosa could be suppressed within approximately ±5%, which is suggested as a tolerance level.  相似文献   
98.
The irradiation field of boron neutron capture therapy (BNCT) consists of multiple dose components including thermal, epithermal and fast neutron, and gamma. The objective of this work was to establish a methodology of dosimetric quality assurance (QA), using the most standard and reliable measurement methods, and to determine tolerance level for each QA measurement for a commercially available accelerator-based BNCT system. In order to establish a system of dosimetric QA suitable for BNCT, the following steps were taken. First, standard measurement points based on tissue-administered doses in BNCT for brain tumors were defined, and clinical tolerances of dosimetric QA measurements were derived from the contribution to total tissue relative biological effectiveness factor-weighted dose for each dose component. Next, a QA program was proposed based on TG-142 and TG-198, and confirmed that it could be assessed whether constancy of each dose component was assured within the limits of tolerances or not by measurements of the proposed QA program. Finally, the validity of the BNCT QA program as an evaluation system was confirmed in a demonstration experiment for long-term measurement over 1 year. These results offer an easy, reliable QA method that is clinically applicable with dosimetric validity for the mixed irradiation field of accelerator-based BNCT.  相似文献   
99.
Purpose: To assess the diagnostic performance of the tumor contact length (TCL) and apparent diffusion coefficient (ADC) for predicting extraprostatic extension (EPE) of prostate cancer with capsular abutment (CA).Methods: Ninety-three patients with biopsy-proven prostate cancer underwent 3-Tesla MRI, including diffusion-weighted imaging (b value = 0, 2000 s/mm2) and radical prostatectomy. Two experienced radiologists, blinded to the clinicopathological data, retrospectively assessed the presence of CA on T2-weighted imaging (T2WI). TCL on T2WI and ADC values were measured on detecting CA in prostate cancer. We used the receiver operating characteristic curves to assess the diagnostic performance of TCL and ADC values for predicting EPE.Results: CA was present in 58 prostate cancers among 93 patients. The cut-off value for TCL was 6.9 mm, which yielded an area under the curve (AUC) of 0.75. This corresponded to a sensitivity, specificity, and accuracy of 84.2%, 61.5%, and 69.0%, respectively. The cut-off value for ADC was 0.63 × 10–3 mm2/s, which yielded an AUC of 0.76. This, in turn, corresponded to a sensitivity, specificity, and accuracy of 84.2%, 59.0%, and 67.2%, respectively. The combined cut-off value of TCL and ADC yielded an AUC of 0.82. The specificity (84.6%) and accuracy (81.0%) of the combined value were superior to their individual values (P < 0.05).Conclusion: A combination of TCL and ADC values provided high specificity and accuracy for detecting EPE of prostatic cancer with CA.  相似文献   
100.
Tranexamic acid (TXA) reduces the risk of bleeding trauma death without altering the need for blood transfusion. We examined the effects of TXA on coagulation and fibrinolysis dynamics and the volume of transfusion during the early stage of trauma. This subanalysis of a prospective multicenter study of severe trauma included 276 patients divided into propensity score–matched groups with and without TXA administration. The effects of TXA on coagulation and fibrinolysis markers immediately at (time point 0) and 3 hours after (time point 3) arrival at the emergency department were investigated. The transfusion volume was determined at 24 hours after admission. TXA was administered to the patients within 3 hours (median, 64 minutes) after injury. Significant reductions in fibrin/fibrinogen degradation products and D-dimer levels from time points 0 to 3 in the TXA group compared with the non-TXA group were confirmed, with no marked differences noted in the 24-hour transfusion volumes between the 2 groups. Continuously increased levels of soluble fibrin, a marker of thrombin generation, from time points 0 to 3 and high levels of plasminogen activator inhibitor-1, a marker of inhibition of fibrinolysis, at time point 3 were observed in both groups. TXA inhibited fibrin(ogen)olysis during the early stage of severe trauma, although this was not associated with a reduction in the transfusion volume. Other confounders affecting the dynamics of fibrinolysis and transfusion requirement need to be clarified.  相似文献   
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