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31.
INTRODUCTION: The present study aimed to investigate the effect of intensive cycle training with short-arm centrifuge-induced hypergravity during bed rest on muscle size and function. METHODS: This study involved 10 healthy men who were divided into 2 groups: a countermeasure group, BR-CM (n = 5); and a control group, BR-Cont (n = 5). The BR-CM subjects partook in intensive cycle training (to 90% of maximum HR) with short-arm centrifuge-induced artificial gravity on alternate days during 20-d bed rest. Muscle volume of the thigh and maximum voluntary contraction (MVC) during isometric knee extensions was measured before and after bed rest. Muscle functional magnetic resonance imaging (mfMRI) and electromyogram (EMG) of the quadriceps femoris were obtained during submaximal knee extension exercises at a load of 30% MVC. RESULTS: The volume of the total thigh muscles was maintained in the BR-CM group (-1%), whereas it was not in the BR-Cont group (-9%, p < 0.05). MVC decreased in the BR-CM (7%) and BR-Cont groups (23%). EMG activity in the BR-CM group after bed rest was significantly lower than that of before; however, no significant change was found in the BR-Cont group. There were no significant changes in the resting and exercised mfMRI signals in either the BR-CM or BR-Cont groups. CONCLUSION: These results suggest that intensive cycle training with hypergravity maintained the size of human skeletal muscles during bed rest.  相似文献   
32.
PURPOSE: To examine cultural incommensurability between clients of Japanese ancestry and Western therapists. DESIGN: Aggregated case-study method was used to analyze psychotherapy cases of Japanese individuals seen by Western therapists. Eight cases were selected for this study from a private practice client pool. FINDINGS: Themes were: (a) only observable data were valued for diagnosis and treatment; (b) cultural stereotypes hampered treatment; (c) individuation and separation occurred within a social web of norms in Japanese culture; (d) key concepts in mental health such as "death and dying" and "rape" were interpreted by clients within a Japanese cultural framework, resulting in unique psychological reactions and behaviors, which had not been recognized by Western therapists; (e) psychological effects of immigration were minimized or ignored by Western therapists; (f) culturally unfamiliar behaviors were "pathologized" by Western therapists; and (g) Western therapists showed ethnocentric biases regarding the effects of immigration. CONCLUSIONS: Various forms of misunderstanding and culturally ignorant practices were found in the treatment of eight Japanese clients by these Western therapists. These ineffective and often harmful practices were unrecognized by the Western therapists.  相似文献   
33.
Combination chemotherapy consisting of bleomycin, ifosfamide, and ciplatin (BIP) is recognized as one of the most effective chemotherapies for uterine cervical cancer. However, there have been no reports that evaluate concurrent use of radiation with BIP. The objective of this study was to evaluate the toxicity and response of the combination of BIP concurrent with radiation in patients with squamous cell carcinoma of the uterine cervix. Eligibility criteria included patients who underwent radical hysterectomy (Type III hysterectomy) as a primary treatment and revealed lymph node metastases or deep myometrial invasion (stage IB and IIA) and patients who were previously untreated (stage IIB-IV). All of the patients had biopsy-proven squamous cell carcinoma of the uterine cervix. The patients received three courses of BIP chemoradiation, and the response and toxicity were evaluated. From January 2000 to December 2003, 30 patients met study eligibility criteria. All but three patients completed 3 courses of planned chemotherapy. The frequency of severe (grade 3 and 4) toxicity was as follows: anemia, 46.7%; neutrocytopenia, 73.3%; thrombocytopenia, 16.7%; and nausea and vomiting, 23.3%. Among 30 patients, 22 cases were evaluated for response. Complete response was achieved in 16 (72.7%) of patients, with a response rate of 90.9%. In conclusion, BIP chemoradiation seems to be superior to previously reported chemoradiation regimens, and has a potential as an optimal combination chemotherapy concurrent with radiation.  相似文献   
34.
Mean levels of left ventricular rhythm and contractility averaged over arrhythmic beats would characterize the average cardiac performance during atrial fibrillation (AF). However, no consensus exists on the minimal number of beats for their reliable mean values. We analyzed their basic statistics to find out such a minimal beat number in canine hearts. We produced AF by electrically stimulating the atrium and measured left ventricular arrhythmic beat interval (RR) and peak isovolumic pressure (LVP). From these, we calculated instantaneous heart rate (HR = 60,000/RR), contractility (E(max) = LVP/isovolumic volume above unstressed volume), and beat interval ratio (RR1/RR2). We found that all their frequency distributions during AF were variably nonnormal with skewness and kurtosis. Their means +/- standard deviations alone cannot represent their nonnormal distributions. A 90% reduction of variances of E(max) and RR1/RR2 required a moving average of 15 and 24, respectively, arrhythmic beats on the average, whereas that of RR and HR required 60 beats on the average. These results indicate that a statistical characterization of arrhythmic cardiodynamic variables facilitates better understanding of cardiac performance during AF.  相似文献   
35.
RATIONALE: Two or three decades ago, cancer pain was treated by surgical/chemical hypophysectomy. In one report, the control of central pain (thalamic pain syndrome) was also approached with chemical hypophysectomy. Although in most of the patients these treatments resulted in a decrease in severe pain, concomitantly severe adverse effects (panhypopituitarism, diabetes insipidus and visual dysfunction) occurred in most patients. This historical evidence prompted us to perform Gamma Knife surgery (GKS) for this kind of intractable severe pain using a high irradiation dose to the pituitary stalk/gland. In the majority of patients, marked pain relief was achieved, surprisingly without any of the complications mentioned above. MATERIALS AND METHODS: A prospective multicenter study was conducted to evaluate the efficacy and safety in patients treated in Prague, Hong Kong and Tokyo. Indications of this treatment were: (1) failure of other effective treatment approaches prior to GKS, (2) good general patient condition (Karnofsky performance status >40%), (3) response to morphine for pain control (cancer pain), and (4) no previous radiotherapy of brain metastases (GKS/conventional radiotherapy). Eight patients with severe cancer pain due to bone metastasis and 12 patients with post-stroke thalamic pain syndrome were treated with GKS. The target was the border between the pituitary stalk and gland. Maximum dose was 160 Gy for cancer pain and 140 Gy for central pain. Follow-up included 6 patients (>1 month) with cancer pain and 8 patients (> 6 months) with thalamic pain syndrome. RESULTS: All patients (6/6) with cancer pain experienced significant pain reduction, and 87.5% (7/8) of the patients with thalamic pain had initially significant pain reduction. In some patients, pain reduction was delayed for several hours. Pain relief was noted within 7 days (median 2 days). No recurrence was observed in the patients with cancer pain. However, in 71.4% (5/7) of the patients with thalamic pain syndrome, disease recurred during the 6-month follow-up. Up to now, other complications have not been observed. CONCLUSION: Our clinical study protocol is only preliminary. Further clinical results on the management of thalamic pain are required to develop this treatment protocol. However, efficacy and safety have been shown in all our cases. In our opinion, this treatment has a potential to control severe pain, and GKS will play an important role in the management of intractable pain.  相似文献   
36.
Transient receptor potential type A1 (TRPA1) is reported to be a Ca2+‐permeable channel and is activated by cold temperatures and mechanical stimuli in the hair cells and in dorsal root ganglion. Using a DNA microarray, we found that TRPA1 was significantly up‐regulated in human periodontal ligament (hPDL) cells 2 d after intermittent mechanical stimulation (iMS) loading compared with unloaded cells. Although hPDL cells are known to respond to mechanical stimulation induced by occlusal force, little is known about the expression and functional role of TRPA1 in these cells. Therefore, we investigated the effects of iMS on TRPA1 expression and its signaling pathway in hPDL cells. Intermittent mechanical stimulation loading up‐regulated TRPA1 expression in hPDL cells in a time‐dependent manner, but had no effect on other mechanoreceptors. Furthermore, iMS significantly increased the phosphorylation of mitogen‐activated protein kinases (MAPKs), especially extracellular signal‐regulated kinase 1/2 (ERK1/2) and p38, and the expression of C‐C chemokine ligand 2 (CCL2). Transient receptor potential type A1 agonists also increased MAPK phosphorylation and the intracellular Ca2+ concentration. By contrast, inhibition or silencing of TRPA1 partially suppressed iMS‐induced MAPK phosphorylation. In summary, iMS during occlusion activates TRPA1 and MAPK signaling in periodontal ligament tissues, suggesting that TRPA1 regulates the mechanosensitivity of occlusal force via activation of MAPKs in hPDL cells.  相似文献   
37.
38.
In this paper we describe a laser Doppler velocimeter (LDV) with an optical fiber that measures blood flow velocities accurately in a small sample volume. The principle, optical arrangement, spatial and the temporal resolutions and accuracy for blood flow measurements are delineated, followed by a report of the results of measurements of coronary artery and vein blood flow velocities in dogs. Finally, we touch upon some recent progress made in the LDV with an optical fiber pickup.  相似文献   
39.
To elucidate the significance of cytoskeletal microtubule networks in striated muscles, we analyzed correlation between the content of tubulin (building block of microtubules) and αB-crystallin (a molecular chaperone for tubulin) in a variety of striated muscles expressing different myosin heavy-chain (MHC) isoforms. The content of both tubulin and αB-crystallin was larger in MHC-I dominant soleus muscle and in MHC-α dominant cardiac (atrium and ventricle) muscles; intermediate in MHC-IId dominant masseter, tongue, and diaphragm muscles; and smaller in MHC-IIb dominant plantaris, gastrocnemius, psoas, extensor digitorum longus, and tibialis anterior muscles. Since the muscles of slow-type MHC (MHC-I/α) show the most economical features in their function and metabolism, which suit for continuous activity required to sustain posture and blood pumping, the present results afforded additional support to our hypothesis that microtubule networks transduce mechanical environmental demands to morphological and biochemical responses that eventually evolve adaptive transformation in the function and metabolism of the mature muscles. The comparison of tubulin/αB-crystalline ratios across the muscles of varied MHC isoforms further suggested that mechanical stress fluctuating at the rhythmic frequency of walking and breathing efficiently activates the hypothesized dynamic function of microtubules.  相似文献   
40.
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