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981.
982.
983.
The early detection of disease is important to keep people healthy, but it is not easy for elderly residents living in rural areas at a distance from well-equipped medical institutes to be examined. Therefore, the present study evaluated the usefulness of real-time telescreening of echocardiography using satellite communications. The participants in this study were 57 residents of a rural community in Japan. The resolution of the real-time ultrasound images sent by communications satellite was almost identical to that of the original images taken in the hospital. Although some problems remain to be solved, telescreening of echocardiography will be a practical method for public health in the near future.  相似文献   
984.
The morphologic changes in peripheral airways of guinea pigs derived from asthmalike breathing induced by acetylcholine (Ach) exposure were studied. In the Ach-exposed animals, the smooth muscle in the respiratory units (alveolar mouth of the alveolar duct) as well as in the peripheral airways was increased. The internal and external diameters of the peripheral airways were not significantly different between Ach-exposed and control animals. In addition, the Ach-exposed animals had higher specific diaphragm weights (diaphragm to body weight). We conclude that recurrent asthmalike breathing brings about increased smooth muscle, but the increased muscle contributes little to airway dimensions. We speculate that an increased airway wall thickness inside the outermost layer of smooth muscle may play a role in increasing airway reactivity.  相似文献   
985.
When cancer metastasizes to bone, the resulting pain and functional disorders due to bone destruction adversely affect the patient''s quality of life. We have developed a new cancer metastasis control system consisting of anticancer agents conjugated to carbon fibers (CFs), which are nonbiodegradable, carriers of a wide variety of molecules with extremely high affinity for bone. In the evaluation of cancer suppression effects on Walker 256 cancer cells, cisplatin (CDDP)-conjugated CFs (CF-CDDP) were found to be as effective in cancer suppression as CDDP. In the evaluation of the cancer suppression effects of local injection in the rat model of tibial cancer bone metastasis, similar cancer suppression was noted in the CF-CDDP group and CDDP group; however, blood Pt concentrations were significantly lower in the CF-CDDP group. Experiments with CDDP and CF-CDDP injected into bone actually destroyed by cancer metastases revealed the presence of significantly more newly formed bone tissue with the administration of CF-CDDP. Local administration of CF-CDDP is expected to become the first therapy to suppress cancer growth with low prevalence of adverse reactions, and to repair bone damaged by metastasis.

Local administration of cisplatin-conjugated carbon fibers is expected to become the first therapy to suppress cancer growth with low prevalence of adverse reactions, and to repair bone damaged by metastasis.  相似文献   
986.
A series of cellulose derivatives bearing dialkyl dithiocarbamate (DTC) groups were synthesized. Their ability of sorption of arsenite (As(iii)) and heavy metals and their storage stability in the solid state were investigated. Among them, DTC-modified cellulose derived from l-proline showed the highest sorption capacity for As(iii) and heavy metals to selectively remove them from aqueous media. It also showed exellent storage stability in air at 40 °C.

Dithiocarbamate-modified cellulose derived from l-proline works as a storable sorbent for selective removal of toxic As(iii) and heavy metals from aqueous media.  相似文献   
987.

Purpose

Temsirolimus (TEM) is a novel, water-soluble mammalian target of rapamycin (mTOR) inhibitor that has shown activity against a wide range of cancers in preclinical models, but its efficacy against colorectal cancer (CRC) has not been fully explored.

Methods

We evaluated the antitumor effect of TEM in CRC cell lines (CaR-1, HT-29, Colon26) in vitro and in vivo. In vitro, cell growth inhibition was assessed using a MTS assay. Apoptosis induction and cell cycle effects were measured using flow cytometry. Modulation of mTOR signaling was measured using immunoblotting. Antitumor activity as a single agent was evaluated in a mouse subcutaneous tumor model of CRC. The effects of adding chloroquine, an autophagy inhibitor, to TEM were evaluated in vitro and in vivo.

Results

In vitro, TEM was effective in inhibiting the growth of two CRC cell lines with highly activated AKT, possibly through the induction of G1 cell cycle arrest via a reduction in cyclin D1 expression, whereas TEM reduced HIF-1α and VEGF in all three cell lines. In a mouse subcutaneous tumor model, TEM inhibited the growth of tumors in all cell lines, not only through direct growth inhibition but also via an anti-angiogenic effect. We also explored the effects of adding chloroquine, an autophagy inhibitor, to TEM. Chloroquine significantly potentiated the antitumor activity of TEM in vitro and in vivo. Moreover, the combination therapy triggered enhanced apoptosis, which corresponded to an increased Bax/Bcl-2 ratio.

Conclusions

Based on these data, we propose TEM with or without chloroquine as a new treatment option for CRC.  相似文献   
988.
Neuroscience and Behavioral Physiology - Among the antidementia drugs, only memantine has a sedative effect. In addition, it also has the effect of prolonging sleep time. However, there are no...  相似文献   
989.
Virus Genes - The exact evolutionary patterns of human G4P[6] rotavirus strains remain to be elucidated. Such strains possess unique and strain-specific genotype constellations, raising the...  相似文献   
990.
The neonatal Fc receptor (FcRn) plays a role in trafficking IgG and albumin and is thought to mediate intravenous immunoglobulin (IVIG) therapy for certain diseases. IVIG can be used for the treatment of human Langerhans cell histiocytosis (LCH); however, the mechanism remains unclear. The expression and function of FcRn protein have not been studied in LCH, though the expression of FcRn messenger RNA (mRNA) have been reported. In this report, we confirmed the expression of FcRn in 26 of 30 pathological cases (86.7%) diagnosed immunohistochemically as LCH. The expression was independent of age, gender, location, multi- or single-system, and the status of BRAFV600E immunostaining. We also confirmed the expression of FcRn mRNA and protein in the human LCH-like cell line, ELD-1. FcRn suppressed albumin consumption and growth of IVIG preparation-treated ELD-1 cells, but not of IVIG preparation-untreated or FcRn-knockdown ELD-1 cells. In addition, FITC-conjugated albumin was taken into Rab11-positive recycle vesicles in mock ELD-1 cells but not in FcRn-knockdown ELD-1 cells. IVIG preparation prolonged this status in mock ELD-1 cells. Therefore, ELD-1 recycled albumin via FcRn and albumin was not used for metabolism. Our results increase our understanding of the molecular mechanism of IVIG treatment of LCH.  相似文献   
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