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31.
The effect of evaluative observation on cardiovascular responses was assessed in 20 female undergraduate students. All participants performed a mental arithmetic (MA) task, and a mirror drawing (MD) task, with or without evaluative observation. Heart rate, blood pressure (BP), admittance plethysmography, and task performance were recorded for each task. Both tasks increased blood pressure, but the hemodynamic response patterns were distinct. The MA task induced enhanced cardiac response, whereas the MD task induced a vascular dominant response. Evaluative observation substantially increased BP during both tasks, but it always enhanced cardiac output and reduced total peripheral resistance. The hemodynamic responses changed significantly from vascular dominant to cardiac dominant, particularly during the MD task. The similarity of responses during evaluative and competitive situations is discussed. The significance of interpersonal factors in psychophysiological studies is emphasized.  相似文献   
32.
Concerning the classification of ventilators, Elam (1958), Faireley (1959), and Hunter (1961) reported some simple ones such as pressure limited, volume limited, pressure preset, or volume preset models. Mapleson (1969) also classified them by the generating force or cycling together with the above-mentioned types.The latest ventilators applicable to patients with respiratory failure usually have some cut-off function at high airway pressures as a safety measure. Therefore, all of them belong to the pressure limited type. Some ventilators are of two types such as the time cycled and pressure cycled type.Therefore, we attempted to classify ventilators into four groups, i.e. the time cycled, volume cycled, pressure cycled and selective time-pressure cycled types according to the fundamental mode of ventilator function, the so-called change of cycling from inspiration to expiration. Each group was further divided into subgroups according to preset dials such as respiratory rate, I/E ratio, inspiration time, expiration time, tidal volume, flow rate and airway pressure.By this method, fifty one ventilators on the market in Japan can be classified without overlapping. Although this classification seems complex, it will be of use in selecting ventilators by emphasizing preset dials according to the users needs, ability or both.(Goto Y, Takahashi K, Harada J et al.: A consideration on the new classification of latest lung ventilators. J Anesth 1: 178–182, 1987)  相似文献   
33.
A broad range of chronic conditions, including heart failure (HF), have been associated with vitamin D deficiency. Existing clinical trials involving vitamin D supplementation in chronic HF patients have been inconclusive. We sought to evaluate the outcomes of patients with vitamin D supplementation, compared with a matched cohort using real-world big data of HF hospitalization. This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). After exclusion criteria, we identified 93,692 patients who were first hospitalized with HF between April 2012 and March 2017 (mean age was 79 ± 12 years, and 52.2% were male). Propensity score (PS) was estimated with logistic regression model, with vitamin D supplementation as the dependent variable and clinically relevant covariates. On PS-matched analysis with 10,974 patients, patients with vitamin D supplementation had lower total in-hospital mortality (6.5 vs. 9.4%, odds ratio: 0.67, p < 0.001) and in-hospital mortality within 7 days and 30 days (0.9 vs. 2.5%, OR, 0.34, and 3.8 vs. 6.5%, OR: 0.56, both p < 0.001). In the sub-group analysis, mortalities in patients with age < 75, diabetes, dyslipidemia, atrial arrhythmia, cancer, renin-angiotensin system blocker, and β-blocker were not affected by vitamin D supplementation. Patients with vitamin D supplementation had a lower in-hospital mortality for HF than patients without vitamin D supplementation in the propensity matched cohort. The identification of specific clinical characteristics in patients benefitting from vitamin D may be useful for determining targets of future randomized control trials.  相似文献   
34.
The neurotoxicity ofn-hexane is thought to be caused ultimately by 2,5-hexanedione (2,5-HD), one of then-hexane metabolites. The potentiation ofn-hexane neurotoxicity by co-exposure with MEK, therefore, is suspected to be related to kinetics of 2,5-HD in blood. To clarify the kinetics ofn-hexane metabolites in the mixed exposure ofn-hexane and MEK, rats were exposed to 2000 ppmn-hexane or a mixture of 2000 ppmn-hexane and 2000 ppm MEK, and the time courses of serumn-hexane metabolites were determined. 2,5-HD in serum increased until 2 h after the end of exposure, when serum 2,5-HD concentration reached a peak of 16.35 g/ml in then-hexane-alone group. In contrast, 2,5-HD in the mixed exposure group increased much more slowly during and after exposure than in then-hexane-alone group. It reached a peak of 2.12 g/ml at 8 h after the end of exposure. Serum MBK, a precursor of 2,5-HD in the co-exposure group, was about half in then-hexane-alone group during exposure. However, MBK decreased more slowly in the co-exposure group than in then-hexane-alone group after the end of the exposure. The results suggest that co-exposed MEK might inhibit oxidation ofn-hexane and decrease clearance ofn-hexane metabolites. Co-exposed MEK did not increase serum 2,5-HD, which was considered a main neurotoxic metabolite. Therefore the enhancement of neurotoxicity could not be attributed to increased serum 2,5-HD in the co-exposed group. The mechanism of enhancement of neurotoxicity ofn-hexane by MEK should be studied further.  相似文献   
35.
During the coronavirus disease 2019 (COVID-19) pandemic, autopsies have provided valuable insights into the pathogenesis of COVID-19. The precise effect of this pandemic on autopsy procedures in Japan, especially in instances unrelated to COVID-19, has not yet been established. Therefore, we conducted a questionnaire survey from December 2020 to January 2021 regarding the status of pathological autopsy practices in Japan during the first year of the COVID-19 pandemic. The questionnaire was sent to 678 medical facilities with pathologists, of which 227 responded. In cases where a confirmed diagnosis of COVID-19 was not made at the time of autopsy, many facilities counted them as suspected COVID-19 cases if pneumonia was suspected clinically. At around half of the sites, autopsies were prohibited for suspected COVID-19 cases. In addition, the number of autopsies of non-COVID-19 cases during the pandemic period was also investigated, and a significant decrease was observed compared with the incidence in the pre-pandemic period. The COVID-19 pandemic has affected not only the autopsies of COVID-19 cases but also the entire practice of pathological autopsies. It is necessary to establish a system that supports the implementation of pathological autopsy practices during the pandemic of an emerging infectious disease.  相似文献   
36.
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology of TAWH.  相似文献   
37.
1. The aim of this study was to examine whether cerivastatin sodium, a new inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, affects the lesional composition of spontaneously developed atherosclerosis due to hypercholesterolaemia and delays progression of the lesions. 2. We administered cerivastatin to 2-month-old WHHL rabbits, a low-density lipoprotein receptor-deficient animal model, at a dose of 0.6 mg kg(-1) day(-1) for 32 weeks. We examined the plasma lipid levels, the severity of atherosclerosis, and composition of atherosclerotic lesions. Lesional composition was determined using immunohistostaining for macrophages and smooth muscle cells, and Azan-Mallory staining for collagen fibres and extracellular lipid deposits. 3. Compared to the control group, the plasma cholesterol levels were decreased in the treated group by 39% (12.7+/-0.6 mmol L(-1) versus 20.9+/-1.0 mmol L(-1), P<0.001). Atherosclerosis was suppressed by about 37% as measured by the thickness of the aortic lesions (158+/-13 microm versus 250+/-15 microm, P<0.001), and by 28% as measured by coronary stenosis (62.7+/-11.4 versus 86.9+/-12.2, P<0.05). In the cerivastatin group, regarding the per cent areas of lesional components in the lesion area, the macrophages (21.0+/-1.5% versus 27.9+/-1.9%, P<0.01) and extracellular lipid deposits (3.2+/-0.4% versus 5.1+/-0.4%, P<0.001) were decreased in the aortic lesions, and the per cent area of macrophages in the coronary lesions was also decreased (4.9+/-1.4% versus, 11.6+/-2.4%. P<0.05). The per cent area of smooth muscle cells and collagen fibres did not significantly decrease. 4. These results indicate that cerivastatin contributed to the plaque stabilization and delayed progression of early atherosclerosis in young WHHL rabbits, in addition to the potent hypolipidemic effects.  相似文献   
38.
Purpose. The goal of this study was to evaluate the ability of nanoparticles to be used as a targeted delivery system for oligonucleotides. Methods. Pharmacokinetic and tissue distribution were carried out in mice by measuring the radioactivity associated to the model oligothymidylate 33P-pdT16 loaded to poly(isobutylcyanoacryrate) (PIBCA) nanoparticles. In addition, we have used a TLC linear analyzer to measure quantitatively on a polyacrylamide gel electrophoresis, the amount of non degraded pdT16 Results. Organ distribution study has shown that nanoparticles deliver 33P-pdT16 specifically to the liver reducing its distribution in the kidney and in the bone marrow. Nanoparticles could partially protect pdT16 against degradation in the plasma and in the liver 5 min after administration, whereas free oligonucleotide was totally degraded at the same time. Conclusions. Nanoparticles protect oligonucleotides in vivo against degradation and deliver them to the liver.  相似文献   
39.
PURPOSE: Loss of function or expression of the mismatch repair gene MLH1 has been implicated in experimentally acquired resistance to cisplatin (CDDP) and other anticancer agents. The clinical significance of MLH1 expression was evaluated in advanced thoracic squamous cell carcinoma of the esophagus (ESCC) treated by neoadjuvant chemotherapy. EXPERIMENTAL DESIGN: We investigated MLH1 and P53 expression by immunohistochemistry in the surgical specimens of 107 patients who had undergone preoperative chemotherapy using CDDP along with 5-FU and ADM. These findings were correlated with the clinical outcome for this treatment. Biopsy samples before chemotherapy in 20 of these patients, and another 43 surgical specimens without chemotherapy, were also examined as control samples. RESULTS: In surgical specimens of ESCC, low MLH1 expression was not frequent without chemotherapy, whereas it was commonly observed after chemotherapy (14 versus 37%, P = 0.0057). Comparison between samples before and after chemotherapy revealed that MLH1 expression was unchanged during chemotherapy in 12 of 20 patients (60%) but was from high to low in 8 of 20 patients (40%). In the surgical specimen after neoadjuvant chemotherapy, MLH1 expression was not correlated with any clinicopathological factors, including the response to chemotherapy. However, low MLH1 showed poorer prognosis than high MLH1 (5-year survival 40.6 versus 19.3%, P = 0.0393), and in multivariate analysis, MLH1 was an independent prognostic factor for this multimodal treatment, following lymph node metastasis and clinical response to chemotherapy. Positive p53 expression, which was not affected by chemotherapy, was weakly associated with a poor response and clinical outcome, although this trend was not significant. CONCLUSIONS: In advanced ESCC, expression of MLH1 is reduced during CDDP-based chemotherapy, and this may partly account for poor postoperative survival.  相似文献   
40.
Soapfishes contain peptide toxins (grammistins) in the skin secretion. Two grammistins (Gs 1 and Gs 2) and six grammistins (Pp 1, Pp 2a, Pp 2b, Pp 3, Pp 4a and Pp 4b) have already been isolated from Grammistes sexlineatus and Pogonoperca punctata, respectively. In this study, five grammistins (Gs A-E), together with grammistins Gs 1 and Gs 2, were further isolated from G. sexlineatus by gel filtration and reverse-phase HPLC. Sequence analyses revealed that grammistins Gs A (28 residues) and Gs C (26 residues) are analogous to grammistin Pp 3 and grammistin Gs B (12 residues) to grammistin Pp 1, while grammistins Gs D (13 residues) and Gs E (13 residues) are identical with grammistins Pp 1 and Pp 2b, respectively. Grammistins Gs A-C exhibited antibacterial activity with a broad spectrum against nine species of bacteria in common with the other grammistins but had no hemolytic activity differing from the other grammistins. Grammistins Gs A-E, Gs 1 and Gs 2 could release carboxyfluorescein entrapped within liposomes made of either phosphatidylcholine or phosphatidylglycerol/phosphatidylcholine (3:1), demonstrating their membrane-lytic activity. However, no clear relationship between the membrane-lytic activity and the biological activity of grammistins was recognized.  相似文献   
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