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101.
Yoshiteru Hasegawa Tatsuya Kasai Toshio Tsuji Susumu Yahagi 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,140(4):387-396
We have reexamined the contradictory evidence in which task-dependent excitation of motor evoked potentials (MEPs) in the first dorsal interosseous (FDI) muscle was stronger with increasingly more complex finger tasks than with individual finger movement tasks. In the first step of the experiment, based on previous findings, we investigated remarkable functional differences between intrinsic and extrinsic hand muscles during complex finger tasks (precision and power grip). During the performance of the tasks, the optimal stimulus intensity of the transcranial magnetic stimulation (TMS) was applied to the contralateral motor cortex. MEPs of the FDI, extensor carpi radialis (ECR), and flexor carpi radialis (FCR) muscles were recorded simultaneously with increased background EMG activity step by step in both tasks. The intensity threshold of TMS was lower in the precision grip. Furthermore, the MEP amplitudes of FDI muscle dependent on the background EMG activity were different between these two tasks, i.e., MEP amplitudes and regression coefficients in a precision grip were larger than those in a power grip. Although our results for MEP amplitude and threshold in the FDI muscle were similar to previous reported evidence, the different contributions of a synergistic muscle (in particular, the ECR muscle) during performance in these tasks was new evidence. Since there were no differences in cutaneous afferent effects on both tasks, corticomotoneuronal (CM) cells connected to FDI motoneurons seemed generally to be more active during precision than power gripping, and there were different contributions from synergistic muscles during the performance of these tasks. In the second part of the experiment, the results obtained from the complex tasks were compared with those from a simple task (isolated index finger flexion). MEP amplitudes, dependent on the background EMG activity during isolated index finger flexion, varied among subjects, i.e., the relationship between the MEP amplitude and the background EMG of the FDI muscle showed individual, strategy-dependent modulation. There were several kinds of individual motor strategies for performing the isolated finger movement. The present results may explain the previous contradictory evidence related to the contribution of the CM system during coordinated finger movement. 相似文献
102.
The polyhedrin gene inBombyx morinucleopolyhedrovirus (BmNPV) was replaced with the granulin gene ofTrichoplusia nigranulovirus (TnGV). The substitution was verified by Southern hybridization, and expression of granulin by the mutant virus, BmGran, was demonstrated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and by amino acid sequencing of the predominant protein of BmGran inclusion bodies (IBs). Light and electron microscopy examination of BmGran-infectedB. moriand BmN cells revealed large, cuboidal, polyhedron-like IBs in the nucleus and cytoplasm, but granules were not seen. IBs contained small, parallel, electron-dense streaks, which defined the geometric pattern of crystallization. Geometric patterns of nuclear IBs were frequently disrupted by occlusion of polyhedron envelope fragments, resulting in IB instability and fracturing. Virions were not embedded in most of the polyhedron-like IBs, but accumulated with polyhedron envelope fragments. Some virions were coated with matrix protein and were partially wrapped by polyhedron envelope. These results suggested that (1) the amino acid sequence of granulin is insufficient for determining IB morphology in TnGV-infected cells, and TnGV may have genes, not present in BmNPV, that control granule formation, and (2) interactions among the virion, the IB envelope, and the matrix protein may be important in virion occlusion and IB morphology and stability. 相似文献
103.
104.
Imai Sojiro Ookawara Susumu Ito Kiyonori Hattori Takashi Fueki Mariko Iguchi Miho Kiryu Satoshi Sanayama Hidenori Kakei Masafumi Tabei Kaoru Morishita Yoshiyuki 《Journal of artificial organs》2023,26(2):127-133
Journal of Artificial Organs - Few reports have examined the association between changes in cerebral oxygenation and clinical factors, including blood pressure (BP), upon standing after... 相似文献
105.
Iwase K Kato K Ohtani S Tsujimura T Hanai T Inagaki A Jimbo S Kobayashi N Yamamoto H Nagasaka A Miura K 《Breast cancer (Tokyo, Japan)》1997,4(3):155-160
The localization of Cu/Zn- and Mn-superoxide dismutase (SOD) in breast cancer tissue (12 papillotubular carcinomas, 21 solid-tubular carcinomas, 16 scirrhous carcinomas, 1 medullary carcinoma, 1 secreting carcinoma, 1 lobular carcinoma, 1 Paget's disease) was investigated via an immunohistochemical technique using antihuman Cu/Zn- and Mn-SOD antibodies in 10%formalin fixed-paraffin embedded thin sections. Both SODs stained strongly in the normal breast gland, but not clearly in many cancer tissues. Furthermore, Cu/Zn-SOD stained more strongly in well differentiated tubular carcinomas than in poorly differentiated tubular carcinomas. It tended to stain less in tumors which recurred or had a poor outcome, and in tumors with a diploid pattern on DNA flow cytometry. Mn-SOD staining was similar to that of Cu/Zn-SOD, but no significant differences among subgroups was found, since the incidence of positively staining tumors was too small in all groups. The intensity of SOD staining seems to change in relation to cell proliferation and differentiation in breast carcinoma, and may be a prognostic indicator, since SOD decreased in poorly differentiated carcinoma and in tumors which developed distant metastasis. Thus, the localization of SOD in breast cancer tissue can provide useful information for cancer treatment. 相似文献
106.
We have developed a breast-conserving surgery consisting of quadrantectomy and regional lymph node dissection and immediate
volume replacement using lateral tissue flap (LTF). The quadrantectomy was employed on the basis of segmental anatomy of the
duct lobular system in which breast carcinoma originates. Lateral skin incision was performed from the apex of mid-axillary
line to the inframammary fold, without removing the skin overlying the tumor. In the early period of breast reconstruction
embraced latissmus dorsi flap (LDF) for 10 patients (reconstruction was not performed on 35 patients), but in the late period
we employed LTF for 56 patients. Four of the 101 patients developed ipsilateral breast cancer during a mean follow-up period
of 48 months, but none died of breast cancer. Among the 56 patients with LTF replacement no patient developed ipsilateral
breast cancer. Fairly good cosmetic outcome was obtained in the patients who underwent the immediate volume replacement. Breast-conserving
surgeries are reviewed, and the surgical procedure using LTF for immediate volume replacement is described. 相似文献
107.
Ohta T Fukuda M Arima K Kawamoto H Hashizume R Arimura T Yamaguchi S 《Breast cancer (Tokyo, Japan)》1997,4(1):17-24
Cyclins and cyclin-dependent kinases may reflect the status of cell proliferation in cancer tissues. The authors sought to
determine whether cdc2 and cyclin D1 are expressed in breast cancer and are useful as prognostic factors. Accumulation of
cdc2 and cyclin D1 proteins was examined in 88 cases of breast cancer using immunoblotting techniques and correlations with
clinicopathological factors and prognoses were investigated. Cdc2 and cyclin D1 proteins were observed in 27.3% and 75.0%
of breast cancers studied, respectively. The incidence of lymph node metastasis was significantly high in cdc2/cyclin D1-double
positive group and low in double negative group. On the other hand, the incidence of estrogen receptor (ER) negative cases
was significantly higher in the cdc2-positive/cyclin D1-negative group. Relapse-free survival times of cdc2-positive cases
were significantly shorter than those of cdc2-negative cases. The relapse-free survival times of cyclin D1-positive cases
also tended to be poorer than those of cyclin D1-negative cases. Multivariate analyses revealed cdc2 as the second most significant
of the prognostic variables, following lymph node status. The three-year relapse-free survival rate of cdc2/cyclin D1-double
positive cases was 58.9%, whereas that of cdc2/cyclin D1-double negative cases was 100%. Cdc2 and cyclin D1 represent the
status of cell proliferation in breast cancer, and may be useful in breast cancer assessment. 相似文献
108.
PCNA immunostaining combined with AgNOR staining in esophageal squamous cell carcinoma to identify patients with a poor prognosis 总被引:6,自引:0,他引:6
Yoshihisa Morisaki Shingo Shima Yutaka Yoshizumi Yoshiaki Sugiura Susumu Tanaka Seiichi Tamai 《Surgery today》1995,25(5):389-395
Immunostaining of the proliferating cell nuclear antigen (PCNA) provides important information about cell kinetics and is easily performed on routinely obtained formalin-fixed, paraffin-embedded materials. We report herein the results of a retrospective study on PCNA staining in esophageal cancer undertaken to determine its significance. As this study indicated that immunoreactivity was preserved in specimens fixed within 24 h, only 31 specimens from surgical patients were available for this investigation. The mean PCNA index of the patients without invasion to the adventitia (35.7±17.9) was significantly lower than that of those with invasion to the adventitia or neighboring structures (49.7±14.5), while the PCNA index did not correlate with other clinicopathologic parameters such as histologic type, lymph node metastases, or prognosis. However, when an analysis of PCNA staining was combined with an analysis of argyrophilic nucleolar organizer region (AgNOR) staining, a correlation with prognosis was found. In fact, seven patients with a high PCNA index (44) and AgNOR count (6) had a significantly poorer prognosis than the remaining 22 (P=0.0014), and six of these seven patients died within 2 years. These results indicate that this combined evaluation may be useful for the identification of patients with a poor prognosis among those undergoing surgery for esophageal squamous cell carcinoma. 相似文献
109.
Susumu Furukawa Tomoyo Matsubara Toshihir Ino Keijiro Yabuta Yoshimi Umezawa Toshikazu Motohashi 《European journal of pediatrics》1994,153(9):663-667
We compared the efficacy of oral administration of pentoxifylline (PTX) and intravenous infusions of gamma globulin (IVGG) combination therapy with that of IVGG in reducing the frequency of coronary-artery lesions (CAL) in children with Kawasaki disease (KD), in a randomized trial. All patients with KD received acetylsalicylic acid (30 mg/kg per day), until the 30th day, after the onset of fever, followed by daily acetylsalicylic acid at a dose of 3-5 mg/kg per day there-after, and intravenous IVGG, 200 mg/kg per day, for 5 consecutive days. In addition, patients randomly assigned to PTX and IVGG combination therapy groups received oral PTX at a dosage of 10 mg/kg per day (low-dose) or 20 mg/kg per day (high-dose), in three divided doses until the 30th day. Patients with KD were all free from CAL prior to treatment. We assessed the presence of CAL by two-dimensional echocardiography which was also done prior to treatment and then twice a week after hospital admission. We detected CAL in 3 of 18 patients (16.7%) in the IVGG therapy group, as compared with 2 of 18 patients (11.1%) in the low-dose PTX and IVGG combination therapy group. There were no significant differences between the two groups. In the next study, we detected CAL in 3 of 21 patients (14.3%) in the IVGG therapy group, as compared with none of 22 patients (0%) in the high-dose PTX and IVGG combination therapy group (2 = 6.4, P < 0.02). No adverse side-effects were observed in 79 patients with KD. 相似文献
110.