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1.
The possibility of single-mode oscillation over a large cavity area for photonic crystal lasers emitting at the photonic band edge has resulted in much interest in such materials for new forms of solid-state laser. In this paper, we measure the photonic bandstructure in our sample and identify the lasing band edge. By mapping out the bandstructure at the /spl Gamma/-point, we have observed fine structure at the band edge. The experimental results are in good agreement with the theoretically predicted bandstructure. Above threshold, we observe a lasing peak at 965 nm at one of the band edges. The far-field distribution of the laser is measured, showing an annular profile and azimuthal polarization. Calculations on the far-field distribution at the lasing band edge suggest the annular profile is due to an anti-symmetric resonant mode.  相似文献   
2.
PURPOSE: To determine the maximum tolerated dose, toxicities, and potential antitumor activity of edatrexate (E), an antifolate agent with enhanced in vitro antitumor activity as compared with methotrexate (M), when given in combination with vinblastine, doxorubicin, cisplatin, and filgrastim (G-CSF) to patients with advanced malignancies. PATIENTS AND METHODS: Thirty-seven patients with advanced malignancies were treated with escalating doses of edatrexate in combination with vinblastine (V), doxorubicin (A), cisplatin (C), and filgrastim (EVAC/G-CSF) following three different subsequently developed schedules. Schedule 1 was patterned after the MVAC regimen, a combination chemotherapy program with activity against different epithelial malignancies, and consisted of E, 40 mg/m2/day, days 1/15/22; V, 3 mg/m2/day, days 2/15/22; A, 30 mg/m2/ day, day 2; C, 70 mg/m2/day, day 2; repeated every 28 days. Schedules 2 and 3 were designed to avoid observed dose-limiting toxicity on schedule 1 consisting of transient elevation of serum creatinine levels and delayed myelosuppression. Schedule 2 consisted of E, 40 or 60 mg/ m2/day, days 1 and 15; V, 3 mg/m2/day, days 2 and 15; A, 30 mg/m2/day, day 2; C, 30 mg/m2/day, days 1 and 2; cycled every 28 days. Schedule 3 consisted of E, 60 to 120 mg/m2/day, day 1; V, 3 mg/m2/day, day 2; A, 30 mg/m2/day, day 2; C, 30 mg/m2/day, days 1 and 2; cycled every 21 days. Filgrastim 5 micrograms/kg/day was given to all patients subcutaneously until the absolute neutrophil count was greater than 10,000/microL postnadir. Three patients were treated on schedule 1, 10 on schedule 2 (four at an E dose of 40 mg/m2/day and six at an E dose of 60 mg/m2/day), and 24 on schedule 3 (six at each of the following E dosages: 60, 80, 100, and 120 mg/m2/day). RESULTS: Dose-limiting toxicities of grade 3 to 4 leukopenia and transient elevation of serum creatinine values were observed in two of three patients treated on schedule 1. A dose-limiting toxicity of grade 3 to 4 leukopenia was noted in two of six patients treated on schedule 2 at an edatrexate dose of 60 mg/m2/day. Two of six patients treated on schedule 3 at an edatrexate dose of 120 mg/m2/day had a dose-limiting toxicity of grade 3 stomatitis (one patient) and grade 3 cytopenia (one patient). Nineteen of 37 patients with evaluable or measurable disease had a response to treatment (response rate 51%, 95% confidence intervals = 35%-67%). Nine of 15 patients with metastatic non-small cell lung cancer responded, including one complete remission (response rate 60%, confidence intervals = 35%-85%). A median survival of 517 days (confidence interval = 163-808 days) and a 1-year survival rate of 60% (confidence interval = 35%-85%) was seen in patients with advanced non-small cell lung cancer. CONCLUSIONS: The maximum tolerated dose and the recommended phase II dose of edatrexate is 100 mg/m2/day when administered as part of the EVAC/G-CSF program following schedule 3. Promising antineoplastic activity against non-small cell lung carcinomas was observed, and a phase II study is planned.  相似文献   
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4.
Deregulation of expression of the cell cycle regulator cyclin D1 (cD1) may be responsible for rapid proliferation of squamous cell carcinoma of the head and neck (SCCHN). We have studied the expression of cD1 in 46 SCCHNs using immunohistochemistry. Before biopsy, the patients received an in vivo infusion of iododeoxyuridine (IdUrd) for cell proliferation assessment. Additionally, the level of apoptosis was estimated using in situ end labeling (ISEL). Among 33 tumors, the proportion of cD1(+) cells varied from 0.5 to 51.3% (19.9 +/- 2.2%). Thirteen tumors did not express cD1. The fraction of S-phase (IdUrd-positive) cells was 26.3 +/- 1.8% in cD1(+) versus 20.0 +/- 2.4% in cD1(-) tumors (P = 0.06). The percentages of cD1(+) cells and of S-phase cells were not correlated (P = 0.37). Apoptosis was detected by ISEL in 15 of 33 tumors studied. ISEL-positive tumors contained a significantly higher proportion of cD1(+) cells (14.9 +/- 2.6%) than cD1(-) ones (7.9 +/- 2.8%; P = 0.03). There was a positive correlation between the percentage of cD1(+) cells and the degree of ISEL (r = 0.54; P < 0.001). In noninvolved oral mucosa, cD1(+) cells were located primarily in the suprabasal layers (29.3 +/- 3.8% versus 1.2 +/- 0. 2% in the basal layer). Only 23 of 44 mucosal specimens contained cD1(+) cells. All cD1(-) samples were proliferatively active and contained IdUrd-labeled cells. The percentage of cD1(+) cells in the oral epithelium from nontumor controls (uvula samples) was significantly higher than in the SCCHN group in both basal (2.4 +/- 0.4%; P = 0.008) and suprabasal (42.7 +/- 3.3%; P = 0.005) layers. Additionally, whereas in uvuli, cD1(+) cells were distributed evenly along the epithelial lining, in SCCHN samples the regions showing cD1 expression alternated with areas in which cD1 expression was undetectable. These data indicate that cD1 expression in SCCHN varies among tumors and is not correlated with cell proliferation. In noninvolved oral mucosa, cD1 expression differs from that in truly normal epithelium obtained from nontumor patients. A correlation between cD1 expression and the extent of ISEL positivity suggests a possible involvement of cD1 expression in the apoptotic pathways.  相似文献   
5.
A case of Klebsiella pneumoniae endophthalmitis metastasized from prostatitis is reported. A 58-year-old alcoholismic man with diabetic diathesis suffered from endophthalmitis which required enucleation of his left eye, when he interrupted the treatment of prostatitis. Metastatic bacterial endophthalmitis from urinary tract infection is rare.  相似文献   
6.
A two-line flow injection analysis (FIA) biosensor was developed which can simultaneously detect bacterial spoilage and the progress of aging. This FIA biosensor was composed of a putrescine oxidase immobilized electrode and a xanthine oxidase immobilized electrode as detectors. The putrescine electrode measures putrescine and cadaverine which are produced by bacteria, and the xanthine electrode measures hypoxanthine and xanthine which accumulate in meat with aging.

The analytical conditions for this system were set as follows; flow rate, 1 ml/ min; water bath temperature, 30 °C; flow buffer, 0.1 M phosphate buffer (pH 7.0); injection volume for putrescine electrode, 200 μl; injection volume for xanthine electrode, 40 μl; and measurement cycle, 2 min.

The linear relationship for standard solution was between 20 and 800 nmol/ml in the putrescine electrode and between 0.1 and 3.0 μmol/ml in the xanthine electrode. The coefficients of variation in standard solutions were 2.14% with the putrescine electrode and 2.83% with the xanthine electrode. The coefficients of variation values in the specimen solution were 3.22% and 3.76%, respectively.

This two-line FIA biosensor was applied to the vacuum-packed beef stored at 0, 5 and 10 °C. The progress of aging could be monitored at all temperatures, and the bacterial spoilage could be detected before the appearance of putrid odor at 5 and 10 °C. However, at 0 °C the putrid odor did not appear during storage, and neither putrescine nor cadaverine was detected. Thus, this FIA biosensor was confirmed to be useful for the quality control of beef aging at 5 and 10 °C, but not at 0 °C.  相似文献   

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8.
The time-dependent behavior of viscosity of clinker pastes was studied with a coaxial cylinder type viscometer. In order to characterize the flow behavior of cement pastes, the flow curve obtained by the minimum values of shear stresses at different shear rates was proposed. Two types of time dependence were found; the increase in viscosity caused by shearing and the increase in minimum viscosity caused by hydration. The effect of sodium lignosulfonate on the flow behavior was also considered.  相似文献   
9.
The aim of this study was to examine whether salivary exosomal miRNAs could be identified as aging biomarkers. Fifteen young healthy volunteers (median age, 21.0 years) and 13 old individuals (median age, 66.0 years) were recruited. Unstimulated whole saliva was collected, salivary exosomes were isolated, and total RNA was extracted. In a microarray, 242 miRNAs were commonly detected in these two mixed samples. Based on the cut-off values of 2- or 0.5-fold changes (FC) and regulatory power for aging process, six candidate miRNAs (miR-24-3p, miR-371a-5p, miR-3175, miR-3162-5p, miR-671-5p, and miR-4667-5p) were selected. After comparing each total RNA obtained by the 15 young and 13 old individuals to validate the FC values using quantitative real-time PCR, miR-24-3p was identified as a novel candidate aging biomarker. This pilot study suggested that salivary exosomal miRNAs could be identified as candidate aging biomarkers. To confirm whether miR-24-3p in salivary exosomes are suitable biomarkers of aging, further validation research is required.  相似文献   
10.
The purpose of this study was to investigate the relationship between osseous changes in the temporomandibular joint (TMJ) and dental attrition in the Japanese macaque. One hundred and thirty Japanese macaque skulls (54 male and 76 female) from animals which had been bred in the same environment, were randomly sampled from a collection at the Primate Research Institute of Kyoto University. The age at death had been recorded in all cases. TMJ osseous changes were independently evaluated by three examiners, and were defined as an irregular surface or a perforated compact bone layer with a markedly irregular surface on either the temporal or condylar components. Age was a significant factor in predicting TMJ osseous changes (P < 0.001). A strong relation was observed between age and dental attrition (P < 0.001), while dental attrition was not a significant factor in predicting TMJ osseous changes (P = 0.334). The prevalence TMJ osseous changes in male animals was slightly higher than in females (P = 0.057). The results of this study suggest that osseous changes in the macaque TMJ are mainly related to age, not to dental attrition.  相似文献   
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