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This article discusses the allocation problem in international fisheries management, which is critical to effective resource management. A number of cases where allocation problems exist are reviewed and trends identified. It is concluded that power relationships between the states involved are an important determinant of allocation outcomes. While this may seem a frustrating conclusion, it nevertheless reflects the realities of international cooperation.  相似文献   
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Background aimsT cells can be redirected to reject cancer by retroviral transduction with a chimeric antigen receptor (CAR) or by administration of a bispecific T cell engager (BiTE). We demonstrate that transfection of T cells with messenger (m) RNA coding for CAR is an alternative strategy.MethodsWe describe the pre-clinical evaluation of a method based on transient modification of expanded T cells with a CD19 CAR directed against B-cell malignancies. CAR mRNA was generated under cell-free conditions in a scalable process using recombinant RNA polymerase. Efficient and non-toxic square-wave electroporation was used to load the mRNA into the cytoplasm of T cells with no risk of insertional mutagenesis.ResultsAfter transfection > 80% of T cells were viable, with 94% CAR expression. Transfected T cells were cytolytic to CD19+ targets and produced interferon (IFN)-γ in response. Killing of CD19+ target cells was demonstrated even at day 8 with undetectable CAR expression. Increasing the concentration of mRNA resulted in higher surface CAR expression, better killing and more IFN-γ release but at the expense of increased activation-induced cell death. Finally, we demonstrated that a second transgene could be introduced by co-electroporation of CXCR4 or CCR7 with CAR to also modify chemotactic responses.ConclusionsWe advocate the transient redirection approach as well suited to meet safety aspects for early phase studies, prior to trials using stably transduced cells once CAR has been proven safe. The simplicity of this methodology also facilitates rapid screening of candidate targets and novel receptors in pre-clinical studies.  相似文献   
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Approximately 1800 female CBA/Ca mice were exposed by inhalation at three dose levels to beta particles from (45)Ca-labeled fused aluminosilicate particles (FAP), to alpha particles from (242)Cm-labeled FAP, or to carrier control FAP. Another group of mice inhaled no FAP and were designated as untreated cage controls. The FAP in combination with these radionuclides was used to achieve the same spatial and temporal distribution of alpha- and beta-particle dose within the irradiated mice. Some mice were killed to determine the clearance of radiolabeled FAP from their lungs, and the remainder were allocated to a life-span study. All animals were subjected to a detailed necropsy. To facilitate the identification of small tumors, the lungs were rendered transparent in methyl salicylate and examined under back illumination for the presence of lesions. Lung nodules and other microscopic lesions were excised for histological examination. The median survival of mice in all groups was approximately 910 days. The control animals lived longer than those that were irradiated, but it was difficult to determine a dose-response relationship for survival among the exposed mice. Benign adenomas and, less frequently, malignant adenocarcinomas were identified in all animal groups. The prevalence of these tumors was approximately 28.8% in the control mice, which is consistent with the results of other studies using the same strain of mouse. After exposure to radionuclide-labeled FAP, there was a significant dose-related increase in the prevalence of lung tumors in (242)Cm- (peak prevalence 55%) and (45)Ca-exposed (peak prevalence 48.6%) mice. The prevalence of tumors in the mice that received (242)Cm-labeled FAP was approximately twice that in the mice that inhaled (45)Ca-labeled FAP within the range of doses employed (0.55-4.69 Gy). Using the ratio of the slope of the linear component of the dose-response curves, the toxicity of the alpha particles relative to the beta particles was 1.5 (90% CI: 0.7, 9.0) for all adenomas and 9.4 (90% CI: 5.0, 23.0) for the less frequent adenocarcinomas. The relative toxicity for adenocarcinomas was found to decrease with increasing dose.  相似文献   
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Strophomenid brachiopods belonging to the generaLeptaena andLepidoleptaena are described from the uppermost Llandovery — Ludlow succession of Gotland, Sweden. In Gotland,Lepidoleptaena comprises the single speciesL. poulseni, andLeptaena includes four species:L. rhomboidalis, L. sperion, L. depressa andL. parvirugata n. sp.L. depressa shows a considerable amount of morphological variation, which is recognised in the two new subspeciesLeptaena depressa visbyensis n. ssp. from the Llandoverian — Wenlockian Visby Formation, andL. depressa lata n. ssp. from the mid-Wenlockian Slite Group. The distribution of the different species is largely substrate-dependent, withLeptaena rhomboidalis andLepidoleptaena poulseni adapted to high-energy environments with firm substrates, whereas the remaining species preferred fine-grained substrates in low-energy environments.   相似文献   
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Generalized relative and absolute risk models are fitted to the latest Japanese atomic bomb survivor solid cancer and leukemia mortality data (through 2000), with the latest (DS02) dosimetry, by classical (regression calibration) and Bayesian techniques, taking account of errors in dose estimates and other uncertainties. Linear-quadratic and linear-quadratic-exponential models are fitted and used to assess risks for contemporary populations of China, Japan, Puerto Rico, the U.S. and the UK. Many of these models are the same as or very similar to models used in the UNSCEAR 2006 report. For a test dose of 0.1 Sv, the solid cancer mortality for a UK population using the generalized linear-quadratic relative risk model is estimated as 5.4% Sv(-1) [90% Bayesian credible interval (BCI) 3.1, 8.0]. At 0.1 Sv, leukemia mortality for a UK population using the generalized linear-quadratic relative risk model is estimated as 0.50% Sv(-1) (90% BCI 0.11, 0.97). Risk estimates varied little between populations; at 0.1 Sv the central estimates ranged from 3.7 to 5.4% Sv(-1) for solid cancers and from 0.4 to 0.6% Sv(-1) for leukemia. Analyses using regression calibration techniques yield central estimates of risk very similar to those for the Bayesian approach. The central estimates of population risk were similar for the generalized absolute risk model and the relative risk model. Linear-quadratic-exponential models predict lower risks (at least at low test doses) and appear to fit as well, although for other (theoretical) reasons we favor the simpler linear-quadratic models.  相似文献   
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