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排序方式: 共有5836条查询结果,搜索用时 15 毫秒
1.
Mitsuhiro Tozaki Kunihiko Fukuda Masafumi Suzuki 《Magnetic resonance in medical sciences》2006,5(3):137-146
PURPOSE: The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. MATERIALS AND METHODS: We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. RESULTS: Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). CONCLUSION: The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging. 相似文献
2.
3.
In July 2001, psychiatric wards for acute treatments (PWAT) were investigated in Japan using a questionnaire to clarify current and recent problems in 79 PWAT. The questionnaires were sent to wards, patients and psychiatrists and were returned by 72.2% overall. The number of admissions per ward was calculated as 21 patients per one month, and comprised half of all admissions to the hospital. 50% were schizophrenia, 17% were affective disordes and 16% involved drug abuse. Seventeen patients were discharged from PWAT per one month, and comprised 43% of all patients discharged from the hospital. These results indicate that both 21 patients admitted and 17 patients discharged per month and needs to maintain the essential standard for PWAT and the standard should be come more flexible as admission from the other unit of ward than PWAT. As rate of re-admission within 3 months after discharge was around 10% of the total number of patients in the ward, 3 months was considered suitable length of acute treatment in the field of psychiatry in Japan. There was one psychiatrist working in PWAT, and specialized psychiatrists had 17.4 patients, the most number of patients among types of psychiatrist. Simulations of one psychiatrist to 16 and to 32 patients in PWAT were performed to determine how many psychiatrists were needed for a ward. When the ratio was 32 patients to 1 psychiatrist, it was necessary to increase the number of psychiatrists to a ward by 1, and in the case of 16 patients, 1-3 psychiatrists were needed. These indicate the standard number of psychiatrists for PWAT should be at most one psychiatrist for the ward or all of the psychiatrists working in PWAT should be allowed to work simultaneously in other wards. Preparing wards to treat acute phase psychiatric patients is a very important role of each psychiatric hospital, the standard for PWAT should include not only a high level of medical staff, but also preparing easy criteria for each hospital. 相似文献
4.
Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy 总被引:2,自引:0,他引:2
Kunihiko Nagasato Tatsufumi Nakamura Ohishi Kiyosumi Kohji Shibayama Masakatsu Motomura Ichinose Katsuhiro Mitsuhiro Tsujihata Shigenobu Nagataki 《Journal of neuroimmunology》1991,32(2):105-109
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM. 相似文献
5.
Akira Ishih Toshio Miyase Tohru Suzuki Francis W. Muregi Mamoru Terada 《Journal of natural medicines》2007,61(2):213-216
Febrifugine and isofebrifugine alkaloid mixtures extracted from the leaves and buds of Hydrangea macrophylla var. Otaksa, collected during different months, in Japan, were quantified using high-performance liquid chromatography. Leaves collected
during the flowering season, namely from June to August, contained 0.16–0.31 mg/g of the alkaloid mixture, whereas those collected
from September to December had less than 0.03 mg/g of the mixture. However, extracts of buds harvested from October to February
contained a consistently larger amount (more than 0.49 mg/g) of the alkaloids. Hot-water extracts from the leaves and buds
collected during different seasons were evaluated for antimalarial activity against Plasmodium yoelii 17XL in mice. The extract of leaves collected in August demonstrated high antimalarial activity, and all mice that received
the extract survived the infection. In contrast, the extract of leaves collected in December showed little activity. The extract
of buds collected in December cleared parasites, but with subsequent mortality to mouse. The present results show that the
amount of antimalarial agent—febrifugine and isofebrifugine mixture—in H. macrophylla var. Otaksa is both part- and season-dependent, suggesting that the choice of plant parts and their harvesting season are important factors
worth considering in the pharmacological use of medicinal plants. 相似文献
6.
Kazushi Kishi Taizo Takeuchi Tetsuo Sonomura Masashi Kimura Keisuke Kita Morio Sato Masaki Terada 《Cardiovascular and interventional radiology》1997,20(1):63-66
In order to treat fistulated esophageal cancer using a flexible stent, a covered flexible stent was constructed by wrapping
a nitinol stent with a thin sheet of Gore-Tex, preserving the stents original advantages of flexibility and a low-profile
introducer system. This stent was used to perform standard radiotherapy in a case of fistulated esophageal cancer. 相似文献
7.
E. D. Chan L. S. Terada M. I. Schwarz 《Journal of the National Medical Association》1995,87(11):826-828
Although the leading causes of fever and pulmonary infiltrates in sickle cell patients are acute bacterial pneumonia and the acute chest syndrome, the former is usually responsive to antibiotics and not protracted, and the clinical course of the latter is short and self-limited. A patient with sickle cell anemia presented with fever and pulmonary infiltrates of several weeks duration that were unresponsive to antibiotics. Gross endobronchial abnormalities were noted on bronchoscopy, and the biopsies were consistent with sarcoidosis. The diagnosis of sarcoidosis can be difficult to establish in a patient with sickle cell anemia and protracted fever since both disorders are associated with chronic interstitial changes on the chest radiograph as well as restrictive physiology. 相似文献
8.
Y Shimoyama H Suma Y Wanibuchi T Takayama Y Terada Y Fukuda T Saito S Furuta 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(12):985-987
Coronary artery bypass grafting with combined arterial graft using the left internal mammary artery (IMA), right IMA, and the right gastroepiploic artery (GEA) was performed in 45 patients with saphenous vein graft (SVG) (29 patients) or without SVG (16 patients) from February 1989 to October 1989. The left IMA was used in all patients, the right IMA was used in 9 patients, and the GEA was used in 43 patients. Perioperative myocardial infarction was noted in two patients who had hospital deaths. Reopening the chest for postoperative bleeding was performed in two patients, and the cerebral accident was noted in one patient. Fourteen patients were operated on without the requirement for blood transfusion. Studied within 3 postoperative months, all arterial grafts were patent though the patency was 97.7% (43/44) in SVG. It is concluded that the combined arterial graft utilizing the IMAs and GEA can be used safely and effectively. 相似文献
9.
N-acetylaspartate is an axon-specific marker of mature white matter in vivo: a biochemical and immunohistochemical study on the rat optic nerve. 总被引:5,自引:0,他引:5
Carl Bjartmar Jan Battistuta Nobuo Terada Erica Dupree Bruce D Trapp 《Annals of neurology》2002,51(1):51-58
Axonal pathology is a major cause of neurological disability in multiple sclerosis. Axonal transection begins at disease onset but remains clinically silent because of compensatory brain mechanisms. Noninvasive surrogate markers for axonal injury are therefore essential to monitor cumulative disease burden in vivo. The neuronal compound N-acetylaspartate, as measured by magnetic resonance spectroscopy, is currently the best and most specific noninvasive marker of axonal pathology in multiple sclerosis. The possibility has been raised, however, that N-acetylaspartate is expressed also by oligodendroglial lineage cells. In order to investigate N-acetylaspartate specificity for white matter axons, transected rat optic nerves were analyzed by high-performance liquid chromatography and immunohistochemistry. In transected adult nerves, N-acetylaspartate and N-acetyl aspartylglutamate decreased in concordance with axonal degeneration and were undetectable 24 days posttransection. Nonproliferating oligodendrocyte progenitor cells, oligodendrocytes, and myelin were abundant in these axon-free nerves. At 24 days posttransection, N-acetylaspartate was increased (42%; p = 0.02) in nontransected contralateral nerves. After transection at postnatal day 4, total N-acetylaspartate decreased by 80% (P14; p = 0.002) and 94% (P20; p = 0.003). In these developing axon-free nerves, 25 to 33% of oligodendrocyte progenitor cells were proliferating. These data validate magnetic resonance spectroscopy measurements of N-acetylaspartate as an axon-specific monitor of central nervous system white matter in vivo. In addition, the results indicate that neuronal adaptation can increase N-acetylaspartate levels, and that 5 to 20% of the N-acetylaspartate in developing white matter is synthesized by proliferating oligodendrocyte progenitor cells. 相似文献
10.
N Morikawa K Higuchi T Tsukamoto M Nakano H Terada 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1989,109(11):858-864
Denopamine (DP) is a new, orally active, selectively positive inotropic agent and used for the treatment of chronic cardiac insufficiency. The therapeutic effects of DP is highly related to its serum concentrations. A simple analytical method has been developed to determine the serum concentration of DP by use of high performance liquid chromatography (HPLC) with electrochemical detection (ECD). In order to extract the DP from the serum, a disposable solid extraction column (Sep-Pak cartridge, C-18) was used. The average recovery was 84.6 +/- 2.7%. The working electrode potential was fixed at 400 mV with a T1 cell, 600 mV with a T2 cell and 650 mV with a Guard cell in ECD. The analysis was performed on a Nova-Pak cartridge C-18 reverse-phase column (100 mm X 8 mm i.d., 4 microns). The mobile phase consisted of 0.1 M potassium phosphate buffer (pH 6.0) and acetonitrile (83: 17, v/v), and the flow rate was 1.0 ml/min. DP and internal standard phenolphthalein (PP) were eluted at 16.5 and 36.0 min, respectively. The peak-height ratio of DP to PP was linearly correlated (r = 0.9998) over a concentrations range between 1.25 and 15.0 ng/ml in the serum. The lowest detectable concentration was 1.0 ng/ml in the serum. The coefficient of variation of reproducibility in the assay was 6.0% By using the present method, serum concentration of DP was measured for four healthy volunteers after a single oral administration of 10 mg DP tablet after a overnight fast. From these DP concentration profiles, pharmacokinetic parameters were calculated.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献