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71.
The aim of this study was to elucidate whether and how the duration and/or amplitude parameters of anticipatory postural adjustments (APAs) affected the task performance in a single step forward from differences in the initial horizontal location of CoM. Ten male subjects performed initiation of a single step forward with the right swing leg with strict regulation of the step length at three initial body positions (Sw, step initiation from a 50% position of the center of pressure (CoP) shift in the maximum lateral right side; N, step initiation from the upright position at rest; St, step initiation from a 50% position of the CoP shift in the maximum lateral left side). The duration required for stepping from the heel-off to foot-contact of the swing leg (step time) in the Sw condition was significantly shorter than of the other two conditions. The APAs durations in the Sw condition was significantly longer than in the other two conditions. In the Sw condition, the durations of the anticipatory electromyographic (EMG) activities of the tibialis anteriors (TA) of the swing leg correlated significantly with mechanical parameters (the displacement of the CoM, velocity of the CoM, and propulsive force) in the anticipatory phase, while the mean amplitudes of the anticipatory EMG activities of the TA of the swing leg did not correlate significantly with mechanical parameters in the anticipatory phase.
The present results suggest that the duration parameters of the APAs associated with single step forward motion are dependent on the displacement of the CoM estimated by the initial cutaneous messages from the swing leg prior to initiation of the single step, and that the APAs may be directly involved not only in the increase in propulsive force towards the supporting leg, but also increasing the forward propulsive force at heel-off. 相似文献
72.
73.
74.
Koushi Yamaguchi Michi Hisano Sakiko Isojima Seiko Irie Naoko Arata Noriyoshi Watanabe Takahiko Kubo Tatsuo Kato Atsuko Murashima 《Journal of medical virology》2009,81(11):1923-1928
To determine the optimal timing for influenza vaccination in pregnant women, we measured alterations in the types 1 and 2 T helper cell (Th1/Th2) balance during pregnancy, monitored specific immunity to inoculated antigens after vaccination with inactivated influenza vaccine, evaluated the relevance of the Th1/Th2 ratio and immune responses to the vaccination, monitored the maintenance of high antibody titers until delivery and measured the transplacental antibody transfer rate. No significant alterations of the Th1/Th2 balance were noted in the 65% of pregnant women among whom the Th1/Th2 ratio was lower than 9.9% in the first trimester. In those groups with a ratio higher than 10% in the first trimester, there was a tendency for the ratio to decrease as gestation advanced. The efficiency of immunization was not influenced by the Th1/Th2 status or by the stage of gestation. The antibody titer decreased steadily with time from 1 month after vaccination to the time of delivery. Conversely, the transfer rate of antibodies from maternal to fetal blood at the time of delivery increased with the duration of gestation after vaccination. Nevertheless, the antibody titers in both maternal and fetal blood were sufficient to afford protection against infection. Thus, efficient influenza vaccination can be undertaken at any stage of pregnancy. J. Med. Virol. 81:1923–1928, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
75.
Araki M Nakazuru S Itoh M Suemura S Mitsuta C Sueyoshi Y Ota M Ohta T Hasegawa H Tatsumi K Yoshio T Toyama T Kuzushita N Mita E 《Gan to kagaku ryoho. Cancer & chemotherapy》2011,38(11):1857-1859
A 66-year-old man was referred to our hospital with obstructive jaundice. Computed tomography(CT)scan showed thickening of the gallbladder wall, invasion into the liver bed, and thickening of the rectal wall. Colonoscopy revealed a type 2 rectal cancer, in which adenocarcinoma was identified by endoscopic biopsy. He was diagnosed with double-cancer of the gallbladder and rectum. Because his gallbladder cancer was more life threatening than his rectal cancer, gemcitabine was administered at 1, 000 mg/m2 on days 1, 8, and 15 of a 28-day course. After 3 courses of gemcitabine, the CT scan showed that the lymph nodes in the hepatoduodenal ligament had been enlarged, and duodenal stenosis had occurred as a result of gallbladder cancer invasion. S-1 was administered orally at doses of 120 mg/day twice daily on days 1-28 of a 42-day course. Partial response was confirmed by CT scan. After 8 courses of S-1, the gallbladder cancer had progressed and liver metastases had appeared. He subsequently died of disease progression. He survived for 17 months after the first course of chemotherapy, and the progression-free survival with S-1 was 10 months. Therefore, S-1 could be an effective agent for synchronous double cancer of the gallbladder and rectum. 相似文献
76.
Fan Zhang Rina Sanuki Naoto Suzuki Akemi Kimura Noriyoshi Shimizu Masao Maeno 《Archives of oral biology》2010,55(9):679-688
Objective
The prostaglandins (PGs) released from osteoblasts can alter the process of bone remodelling. Recently, we showed that compressive force induced the expression of pro-inflammatory cytokine interleukin (IL)-17s and their receptors in osteoblastic MC3T3-E1 cells and that IL-17A was expressed most highly. Consequently, in the current study we examined the effect of IL-17A and/or celecoxib on PGE2 production and the expression of cyclooxygenases (COXs) and inflammatory cytokines in MC3T3-E1 cells. We also examined the effects of PGE2 and cyclohexamide on the expression of inflammatory cytokines.Methods
Cells were cultured with or without IL-17A (0.1, 1.0, or 10 ng/ml) in the presence or absence of 10 μM celecoxib, a specific inhibitor of COX-2, for up to 72 h. Cells were pretreated with or without 10 μg/ml cycloheximide, protein synthesis inhibitor, for 30 min, and then cultured with 10 ng/ml IL-17A for 24 h. Cells were also cultured with or without 1.5 ng/ml PGE2 for 24 h. PGE2 production was determined by ELISA. The expression of COX-1, COX-2, IL-1α, IL-6, IL-8, IL-11, and TNF-α mRNAs and proteins was determined by real-time PCR and ELISA, respectively.Results
The expression of COX-2, IL-1α, IL-6, IL-8, IL-11, and TNF-α, as well as PGE2 production increased in the presence of IL-17A, whereas COX-1 expression did not change. Celecoxib blocked the stimulatory effect of IL-17A on the expression of COX-2, IL-1α, IL-6, IL-8, and IL-11 as well as PGE2 production, whereas it did not block TNF-α expression. Cycloheximide pretreatment suppressed the expression of IL-17-induced inflammatory cytokines. The expression of IL-1α, IL-6, IL-8, and IL-11 increased by the addition of PGE2, whereas TNF-α expression was not affected.Conclusion
These results suggest that IL-17A stimulates the expression of bone resorption-related inflammatory cytokines through an autocrine mechanism involving celecoxib-blocked PGs, mainly PGE2, in osteoblasts. 相似文献77.
Masunaga H Tsutae W Oh H Shinozuka N Kishimoto N Ogata Y 《Journal of Oral Science》2010,52(4):615-621
Periodontal disease is associated with specific periodontal pathogens and may persist as gingivitis or progress to more severe disease. The bacteria involved in disease initiation and progression have not been identified. We used quantitative polymerase chain reaction (PCR) to compare the levels of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, and total bacteria detected by different sampling methods. On the basis of the results of clinical examinations, 57 patients were divided into 3 groups: healthy group (group A), gingivitis group (group B), and periodontitis group (group C). Bacterial samples were collected from saliva, mouthwash, and by paper-point sampling of gingival crevicular fluid (GCF), and the samples were analyzed with quantitative PCR targeting 16S rRNA. The numbers of total bacteria in samples of GCF, saliva, and mouthwash were 10? to 10?, 10?, and 10?, respectively, per milliliter. The number of P. gingivalis in GCF samples was lower than 10 in group A; however, in groups B and C, the values were 103 and 10?, respectively, indicating that the number of P. gingivalis increased with worsening clinical status. Findings were similar in the samples of saliva and mouthwash. The numbers of T. forsythia showed a pattern similar to that of P. gingivalis in all 3 samples. These results suggest that saliva and mouthwash samples are clinically useful for bacterial testing of periodontal diseases by quantitative PCR. In addition, mouthwash sampling is more feasible and straightforward than saliva sampling. 相似文献
78.
Hai-Lei Zhu Richard D Wassall Maki Takai Hidetaka Morinaga Masatoshi Nomura Thomas C Cunnane Noriyoshi Teramoto 《British journal of pharmacology》2009,157(8):1483-1493
Background and purpose:
The effects of veratridine, an alkaloid found in Liliaceae plants, on tetrodotoxin (TTX)-sensitive voltage-gated Na+ channels were investigated in mouse vas deferens.Experimental approach:
Effects of veratridine on TTX-sensitive Na+ currents (INa) in vas deferens myocytes dispersed from BALB/c mice, homozygous mice with a null allele of NaV1.6 (NaV1.6−/−) and wild-type mice (NaV1.6+/+) were studied using patch-clamp techniques. Tension measurements were also performed to compare the effects of veratridine on phasic contractions in intact tissues.Key results:
In whole-cell configuration, veratridine had a concentration-dependent dual action on the peak amplitude of INa: INa was enhanced by veratridine (1–10 µM), while higher concentrations (≥30 µM) inhibited INa. Additionally, two membrane current components were evoked by veratridine, namely a sustained inward current during the duration of the depolarizing rectangular pulse and a tail current at the repolarization. Although veratridine caused little shift of the voltage dependence of the steady-state inactivation curve and the activation curve for INa, veratridine enhanced a non-inactivating component of INa. Veratridine caused no detectable contractions in vas deferens from NaV1.6−/− mice, although in tissues from NaV1.6+/+ mice, veratridine (≥3 µM) induced TTX-sensitive contractions. Similarly, no detectable inward currents were evoked by veratridine in NaV1.6−/− vas deferens myocytes, while veratridine elicited both the sustained and tail currents in cells taken from NaV1.6+/+ mice.Conclusions and implications:
These results suggest that veratridine possesses a dual action on INa and that the veratridine-induced activation of contraction is induced by the activation of NaV1.6 channels. 相似文献79.
Umezu H Tamura M Kobayashi S Sawabata N Honma K Miyoshi S 《General thoracic and cardiovascular surgery》2008,56(4):199-202
Tracheal chondrosarcomas are rare, with only 14 cases previously documented. We report a case of chondrosarcoma of the trachea
and review other published cases. Our patient was a 34-year-old man who began to feel shortness of breath 8 months after initial
hemoptysis. Transverse and coronal computed tomography demonstrated a tumor that was obstructing nearly 80% of the tracheal
lumen at the thoracic inlet. A bronchoscopic biopsy specimen led to an initial diagnosis of chondroma. Five tracheal rings
from the third to the seventh including the tumor were completely resected, and an end-to-end anastomosis was performed. The
histological diagnosis of the surgical specimen showed it to be a chondrosarcoma. The patient was alive without recurrence
at 6 years 4 months after surgery. Because recurrence after incomplete resection and malignant transformation can occur with
chondromas, radical resection of the trachea is recommended for all cartilaginous tumors of the trachea. 相似文献
80.
Tomoda T Zhu HL Iwasa K Aishima M Shibata A Seki N Naito S Teramoto N 《Naunyn-Schmiedeberg's archives of pharmacology》2007,376(3):195-203
The inhibitory effects of flavoxate hydrochloride (piperidinoethyl-3-methylflavone-8-carboxylate; hereafter referred as flavoxate)
on voltage-dependent nifedipine-sensitive inward Ba2+ currents (I
Ba) in human detrusor myocytes were investigated at different temperatures using conventional whole-cell patch-clamp techniques.
When the bath-solution temperature was increased from 22°C to 30°C, I
Ba peak amplitude was enhanced by approximately twice at several test potentials. Neither the I
Ba threshold nor the membrane potentials for the I
Ba maximum peak amplitude was affected by the temperature change. The concentration-response curves of flavoxate at both 30°C
(K
i
= 5.1 μM) and 37°C (K
i
= 4.6 μM) were slightly shifted to the left in comparison with that at 22°C (K
i
= 10.3 μM). Similar results were also obtained in the presence of nifedipine (K
i
= 14 nM at 22°C vs. K
i
= 2.5 nM at 30°C and K
i
= 2.1 nM at 37°C). Altering the bath-solution temperature from 22°C to 30°C shifted the steady-state inactivation curve of
I
Ba at −90 mV to the left. At 30°C, the steady-state inactivation curve of I
Ba in the presence of flavoxate was also shifted to the left in comparison with that in the absence of flavoxate. Either 3-isobutyl-1-methylxanthine
(IBMX) or theophylline, a phosphodiesterase inhibitor, caused little effects on I
Ba, although cyclic nucleotides (dibutyryl cAMP and 8-Br-cGMP) inhibited I
Ba. These results suggest that the inhibitory actions of flavoxate on I
Ba in human detrusor myocytes were slightly changed at different experimental temperatures and that flavoxate directly blocked
voltage-dependent L-type Ca2+ channels, not through the inhibition of phosphodiesterase activity pathway. 相似文献