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81.
To make a base polymer of a new soft resin material, a copolymer of 1,3-Bis(methacryloxypropyl)tetramethyl disiloxane (BMPMS) and methyl methacrylate monomer (MMA) was investigated. It was found that the compressive strength, bending strength and bending modulus value of the copolymer decreased with increase in BMPMS concentration. While, transverse deflection increased with increase in BMPMS concentration. As for the 50% inhibitory concentration value, it was about 0.8 mM for BMPMS.  相似文献   
82.
The patient suffering from getting something lodged was admitted to our hospital in October 2008. He was diagnosed as hypopharyngeal cancer (cT2N1M0, cStage III) and cervical esophageal cancer (cT2N1M0, cStage III). Firstly he was administered 5-FU, DXR and CDDP as induction chemotherapy. The response evaluation was PR according to RECIST criteria. After the induction chemotherapy, he was treated with chemoradiotherapy (64.8 Gy/54 fr, concurrent with weekly DOC 10 mg/m2). Since cervical lymph node metastases were still remaining with complete response of the primary sites, we performed a neck lymph node dissection as salvage surgery in July 2009. There has been no evidence of recurrence after the salvage surgery.  相似文献   
83.
STUDY OBJECTIVE: To test the hypothesis that the change of body and head position affects upper airway patency during midazolam sedation. DESIGN: Clinical study using 30 healthy subjects. SETTING: Research unit for sleep study. INTERVENTIONS: We used a pressure-flow relationship to evaluate critical closing pressure (Pcrit) and upper airway resistance (Rua) in different condition of body and head position. A pressure-flow relationship was obtained in 3 body postures (supine, 15 degrees elevation, and 30 degrees elevation) and was obtained in 3 head positions (supine with the head in the neutral, supine with head extension, and supine position with head rotated). MEASUREMENTS: The pressure and inspiratory flow at subjects' nose mask were recorded. Polysomnographic parameters (electroencephalograms, electrooculograms, submental electromyograms, upper esophageal pressure, and plethysmogram) were also recorded. MAIN RESULTS: In experiment 1, 30 degrees elevation of the body significantly decreased Pcrit (P < 0.05) to -13.3 +/- 1.3 cm H(2)O compared with -8.2 +/- 1.4 cm H(2)O in supine condition without changing the slope (1/Rua). In experiment 2, head extension significantly decreased Pcrit (-12.5 +/- 1.3 cm H(2)O) (P < 0.05) compared with the value (-8.2 +/- 1.0 cm H(2)O) in supine condition without changing the slope (1/Rua). CONCLUSIONS: Our findings indicate that 30 degrees body elevation and head extension significantly decreased upper airway collapsibility during midazolam sedation and established the relative potency of maneuvers that maintain upper airway patency.  相似文献   
84.
Purpose To determine the incidence of central venous catheter (CVC) complications and to analyze the potential risk factors for complications necessitating CVC removal in patients on home parenteral nutrition (HPN). Methods We studied 68 patients on HPN (44 men and 24 women), examining the incidence of CVC complications and CVC-related infections. The risk factors for CVC-related infection were investigated using multivariate logistic regression analysis. Results the incidences of CVC complications were 0.29 episodes per CVC-year in 45 patients with an external tunneled CVC, and 0.66 episodes per CVC-year in 23 patients with an implanted port device. The incidences of CVC-related infections were 0.17 episodes per CVC-year for external tunneled CVCs and 0.17 episodes per CVC-year for implanted port devices. There were no significant differences in the incidences of CVC complications (P = 0.095), and CVC-related infections (P = 0.406). The incidences of CVC-related infections were 0.04 episodes per CVC-year in 54 patients with malignancies, and 0.68 episodes in 14 patients with benign diseases (P < 0.001). Multivariate logistic regression analysis revealed the types of diseases that influenced the incidence of CVC-related infections (P < 0.05). Conclusions The incidence of CVC complications did not differ between the two groups. The type of disease was the most important predictive factor of CVC-related infections.  相似文献   
85.
Purpose The aim of this retrospective study was to clarify the relation between the reversibility of posterior reversible encephalopathy syndrome (PRES) with three factors: the anatomical region of the brain involved, the background clinical cause, and the diffusion weighted image (DWI) intensity of PRES lesions. Material and methods This multicenter study, conducted by the PRES Study Group of the Neuroradiology Workshop, involved 52 cases from 28 institutions. Initial and follow-up magnetic resonance imaging were compared regarding the reversibility of PRES lesions according to anatomical location and clinical background. Initial DWI and apparent diffusion coefficient (ADC) maps were reviewed in 20 cases. Results Reversibility was significantly lower (P < 0.01) in the brain stem (44%) and deep white matter (47%) compared to the other cortical and subcortical areas (76%–91%). The reversibility was greater in the eclampsia subgroup followed by the hypertension and chemotherapy subgroups. DWI, even with ADC maps, had limitations in predicting the outcome of PRES lesions. Conclusion The typical cortical and subcortical PRES lesions showed reversibility, whereas the brain stem and deep white matter lesions showed less reversibility. PRES due to eclampsia showed maximum reversibility compared to hypertension- and drug-related PRES. DWI, even with ADC maps, had limitations in predicting the course of PRES. Some parts of the study were used for poster presentations at the Japan Radiological Society meetings in 2005 and 2006, in Yokohama, Japan.  相似文献   
86.
A 72-year-old female developed pancytopenia 4 years after breast cancer surgery. She had received regional radiation postoperatively, and tamoxifen for 4 years. Bone marrow examination demonstrated immature myeloblasts and dysplastic cells. Myelodysplastic syndrome (MDS) of refractory anemia with excess blasts (RAEB) was diagnosed, and the patient died of cerebral hemorrhage 4 months after the diagnosis of RAEB. Radiation and the administration of tamoxifen were suspected to have played a role in the development of secondary MDS.  相似文献   
87.
The TEL (ETV6)-AML1 (RUNX1) chimeric gene fusion is the most common genetic abnormality in childhood acute lymphoblastic leukemias. Evidence suggests that this chimeric gene fusion constitutes an initiating mutation that is necessary but insufficient for the development of leukemia. In a search for additional genetic events that could be linked to the development of leukemia, we applied a genome-wide array-comparative genomic hybridization technique to 24 TEL-AML1 leukemia samples and two cell lines. It was found that at least two chromosomal imbalances were involved in all samples. Recurrent regions of chromosomal imbalance (>10% of cases) and representative involved genes were gain of chromosomes 10 (17%) and 21q (25%; RUNX1) and loss of 12p13.2 (87%; TEL), 9p21.3 (29%; p16INK4a/ARF), 9p13.2 (25%; PAX5), 12q21.3 (25%; BTG1), 3p21 (21%; LIMD1), 6q21 (17%; AIM1 and BLIMP1), 4q31.23 (17%; NR3C2), 11q22-q23 (13%; ATM) and 19q13.11-q13.12 (13%; PDCD5). Enforced expression of TEL and to a lesser extent BTG1, both single genes known to be located in their respective minimum common region of loss, inhibited proliferation of the TEL-AML1 cell line Reh. Together, these findings suggest that some of the genes identified as lost by array-comparative genomic hybridization may partly account for the development of leukemia.  相似文献   
88.
89.
There is still concern about the effects of organotin compounds (OTs) on marine organisms, and especially on their reproductive systems. We investigated the toxicity of tributyltin oxide (TBTO) on spermatogenesis in a marine fish, mummichog, Fundulus heteroclitus. TBTO exposure caused serious histological damage to the testis, including reduction in counts of spermatids and spermatozoa and malformation of somatic cells around the seminal duct. Analysis of the incorporation of bromodeoxyuridine into spermatogenic cells revealed inhibition of the proliferation of germ cells. To find a biomarker for evaluation of the effects of TBTO on fish spermatogenesis, we cloned genes downregulated by TBTO exposure in the mummichog testis, and identified mummichog creatine kinase (mCK). The cDNA sequence of mCK contained an open reading frame encoding 387 amino acid residues (M(r)=43,344). The derived amino acid sequence of mCK was very similar to that of the testicular-type CK of the rainbow trout, Oncorhynchus mykiss. Furthermore, Northern blot analysis revealed that mCK was produced specifically in the testis. We therefore identified mCK in the mummichog as a testicular-type CK. Real-time PCR revealed that exposure of the fish to TBTO significantly reduced mCK expression in the testis. To some extent, this reduction was coincident with that of bromodeoxyuridine incorporation into spermatogenic cells. The mCK gene can therefore be used as a biomarker for evaluating the effects of TBTO on fish spermatogenesis. In addition, levels of expression of the mCK gene in control fish were well correlated with increments in the gonad somatic index (GSI) below 4%. Individuals that were thought to have testicular damage caused by TBTO could be discriminated from those considered normal. The results suggest that TBTO is involved in the suppression of fish spermatogenesis and that analysis of both GSI values and mCK gene expression is useful for evaluating the levels of xenobiotic pollution in coastal areas.  相似文献   
90.
The adrenal glands and sympathetic celiac ganglia are innervated mainly by the greater splanchnic nerves, which contain preganglionic sympathetic nerves that originated from the thoracic spinal cord. The adrenal medulla has two separate populations of chromaffin cells, adrenaline-containing cells (A-cells) and noradrenaline-containing cells (NA-cells), which have been shown to be differentially innervated by separate groups of the preganglionic sympathetic neurons. The present study was designed to characterize the centrally activating mechanisms of the adrenal A-cells, NA-cells and celiac sympathetic ganglia with expression of cFos (a marker for neural excitation), in regard to the brain prostanoids, in anesthetized rats. Intracerebroventricularly (i.c.v.) administered corticotropin-releasing factor (CRF) induced cFos expression in the adrenal A-cells, but not NA-cells, and celiac ganglia. On the other hand, i.c.v. administered arginine-vasopressin (AVP) resulted in cFos induction in both A-cells and NA-cells in the adrenal medulla, but not in the celiac ganglia. Intracerebroventricular pretreatment with indomethacin (an inhibitor of cyclooxygenase) abolished the CRF- and AVP-induced cFos expression in all regions described above. On the other hand, intracerebroventricular pretreatment with furegrelate (an inhibitor of thromboxane A2 synthase) abolished the CRF-induced cFos expression in the adrenal A-cells, but not in the celiac ganglia, and also abolished the AVP-induced cFos expression in both A-cells and NA-cells in the adrenal medulla. These results suggest that centrally administered CRF activates adrenal A-cells and celiac sympathetic ganglia by brain thromboxane A2-mediated and other prostanoid than thromboxane A2 (probably prostaglandin E2)-mediated mechanisms, respectively. On the other hand, centrally administered AVP activates adrenal A-cells and NA-cells by brain thromboxane A2-mediated mechanisms in rats.  相似文献   
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