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73.
A new class of photorefractive (PR) composite based on a fully functionalized polymer with high phase‐stability is reported. The polymer containing non‐linear optical (NLO) chromophores and charge‐transporting carbazole moieties is synthesized by a polymer‐analogous reaction. The polymer is doped with plasticizer, NLO dye, and sensitizer to fabricate the PR composite. The NLO dye is the same as the NLO chromophore moiety in the polymer side chain. The PR performance of the composite is evaluated by degenerated four‐wave mixing and two‐beam coupling measurements. A diffraction efficiency of 30% at a relatively low applied electric field of 45 V μm?1 is achieved. Despite a high concentration of NLO dye, the composites show good stability for a long period without phase separation.  相似文献   
74.
We report a near-fatal case of cerebral edema associated with adenovirus type 2 infection in a previously healthy 19-month-old boy. After 3 to 4 d of high fever and a series of seizures, he developed persistent loss of consciousness and irreversible respiratory arrest. Adenovirus type 2 infection was diagnosed by virus isolation from his stool and serology.  相似文献   
75.
Hsp90 inhibitors are being evaluated extensively in patients with advanced cancers. However, the impact of Hsp90 inhibition on signaling pathways in normal tissues and the effect that this may have on the antitumor activity of these molecularly targeted drugs have not been rigorously examined. Breast and prostate carcinomas are among those cancers that respond to Hsp90 inhibitors in animal xenograft models and in early studies in patients. Because these cancers frequently metastasize to bone, it is important to determine the impact of Hsp90 inhibitors in the bone environment. In the current study, we show that, in contrast to its activity against prostate cancer cells in vitro and its inhibition of s.c. prostate cancer xenografts, the Hsp90 inhibitor 17-AAG stimulates the intraosseous growth of PC-3M prostate carcinoma cells. This activity is mediated not by a direct effect on the tumor but by Hsp90-dependent stimulation of osteoclast maturation. Hsp90 inhibition transiently activates osteoclast Src kinase and promotes Src-dependent Akt activation. Both kinases are key drivers of osteoclast maturation, and three agents that block osteoclastogenesis, the Src inhibitor dasatinib, the bisphosphonate alendronate, and the osteoclast-specific apoptosis-inducer reveromycin A, markedly reduced 17-AAG-stimulated tumor growth in bone. These data emphasize the importance of understanding the complex role played by Hsp90 in regulating signal transduction pathways in normal tissues as well as in cancer cells, and they demonstrate that drug-dependent modulation of the local tumor environment may profoundly affect the antitumor efficacy of Hsp90-directed therapy.  相似文献   
76.
Periostin/OSF2 is a ligand for alphavbeta3 and alphavbeta5 integrins and activates the Akt/PKB pathway. Recent reports of periostin/OSF2 gene disrupted mice indicate that periostin/OSF-2 plays an important role in implantation. Quantitative RT-PCR revealed that the expression of periostin/OSF-2 mRNA in rat uteri was reduced to approximately 10% at 12 h after 17beta-estradiol (E2) injection, but was not changed after progesterone (P) injection. RT-PCR revealed the expression of periostin/OSF-2 in human endometrium, cultured human endometrial stromal cells (ESCs), and cultured human endometrial epithelial cells. In ESCs, the expression of periostin/OSF-2 mRNA was reduced to approximately 50% at 6 h after E2 treatment. The amount of periostin/OSF2 mRNA in human endometrium significantly increased during mid-proliferative and early secretory phases of menstrual cycle, and decreased during late-proliferative, mid-secretory and late secretory phases. The expression of periostin/OSF2 mRNA significantly decreased in ESCs decidualized by treatment with E2 and P for 7 and 11 days. By immunohistochemistry, the expression of periostin/OSF-2 was strongly detected in endometrial stromal cells during early proliferative, mid-proliferative and early secretory phases, and was strongly detected in endometrial epithelial cells during late secretory phase. This study demonstrated that the expression of periostin/OSF-2 is regulated by ovarian steroid hormones in rat uterus and human endometrium.  相似文献   
77.
This study prospectively assessed subclinical cardiotoxicity in patients undergoing chemotherapy by using the Tei index combining systolic and diastolic time intervals. A significant difference in the Tei index was observed between patients who received a low dose and those who received a moderate to high dose of anthracycline antibiotic drugs. The Tei index is a sensitive, accurate, and easy approach for detecting subclinical anthracycline cardiotoxicity.  相似文献   
78.
We present a case of severe exacerbation of hepatitis after short-term corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIPD) with "latent" chronic hepatitis B showing no HBV-related antigens and antibodies. After corticosteroid pulse therapy for CIPD, the patient had severe exacerbation of hepatitis twice. Although she did not show any hepatitis B virus (HBV)-related antigens or antibodies, sequences of HBV were detected in serum and liver by a nested polymerase chain reaction. A sequence analysis of HBV at the second exacerbation showed that the G-to-A point mutation at nucleotide 1896 that converted codon 28 from tryptophan (TGG) to a stop codon (TAG) in the precore region resulted in amino acid change, which has been frequently observed in fulminant hepatitis and severe hepatitis in Japan.  相似文献   
79.
Fiberoptic bronchoscopy is a well established methods as a useful tool in the diagnosis of pulmonary tuberculosis with smear negative cases. In order to get the early and definite diagnosis of pulmonary tuberculosis, we performed transbronchial aspiration and bronchial lavage by a fiberoptic bronchoscope in 97 patients. All patients (1) were clinically suspected of having active tuberculosis; (2) showed abnormal chest roentgenogram suggesting tuberculosis; (3) showed negative sputum smears of acid-fast bacilli, or had no sputum. The results of the study were summarized as follows: 1) Final diagnosis of study subjects were 90 patients of active pulmonary tuberculosis, and 7 patients of pulmonary atypical mycobacteriosis. 2) Sputum culture of acid-fast bacilli was positive in 22 out of 90 patients with active pulmonary tuberculosis. 3) Smear and culture examination of acid-fast bacilli of transbronchial aspirates were positive in 9 and 28, respectively out of 90 patients. 4) Smear and culture examination of acid-fast bacilli of bronchial lavage were positive in 12 and 39, respectively out of 90 patients. 5) A rapid and definite diagnosis was made in 16 out of 90 patients by transbronchial aspirates or bronchial lavage. 6) Atypical mycobacteria were detected in 7 out of 97 patients by transbronchial aspirates or bronchial lavage. 7) There were no serious complications such as pneumonia and exacerbation of pulmonary tuberculosis. These results suggested that transbronchial aspiration and bronchial lavage were useful procedures for rapid and definite diagnosis of pulmonary tuberculosis.  相似文献   
80.
Abstract: We present a case of severe exacerbation of hepatitis after short‐term corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIPD) with “latent” chronic hepatitis B showing no HBV‐related antigens and antibodies. After corticosteroid pulse therapy for CIPD, the patient had severe exacerbation of hepatitis twice. Although she did not show any hepatitis B virus (HBV)‐related antigens or antibodies, sequences of HBV were detected in serum and liver by a nested polymerase chain reaction. A sequence analysis of HBV at the second exacerbation showed that the G‐to‐A point mutation at nucleotide 1896 that converted codon 28 from tryptophan (TGG) to a stop codon (TAG) in the precore region resulted in amino acid change, which has been frequently observed in fulminant hepatitis and severe hepatitis in Japan.  相似文献   
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