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141.
Modern diffusion MR protocols allow one to acquire the multi-shell diffusion data with high diffusion weightings in a clinically feasible time. In the present work we assessed three diffusion approaches based on diffusion and kurtosis tensor imaging (DTI, DKI), and neurite orientation dispersion and density imaging (NODDI) as possible biomarkers for human brain glioma grade differentiation based on the one diffusion protocol. We used three diffusion weightings (so called b-values) equal to 0, 1000, and 2500 s/mm2 with 60 non-coplanar diffusion directions in the case of non-zero b-values. The patient groups of the glioma grades II, III, and IV consist of 8 subjects per group. We found that DKI, and NODDI scalar metrics can be effectively used as glioma grade biomarkers with a significant difference (p < 0.05) for grading between low- and high-grade gliomas, in particular, for glioma II versus glioma III grades, and glioma III versus glioma IV grades. The use of mean/axial kurtosis and intra-axonal fraction/orientation dispersion index metrics allowed us to obtain the most feasible and reliable differentiation criteria. For example, in the case of glioma grades II, III, and IV the mean kurtosis is equal to 0.31, 0.51, and 0.90, and the orientation dispersion index is equal to 0.14, 0.30, and 0.59, respectively. The limitations and perspectives of the biophysical diffusion models based on intra-/extra-axonal compartmentalisation for glioma differentiation are discussed. 相似文献
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Marluce Bibbo Peter H. Bartels Harvey E. Dytch James H. Puls Frederick T. Pishotta George L. Wied 《Cell biochemistry and biophysics》1983,5(1):61-69
Comparison was made between cytophotometric measurements obtained using two data acquisition systems, one a microphotometer
and the other a rapid video camera system, to ascertain whether the degradation of data with the faster video acquisition
system still results in recorded images of sufficient quality to permit computer discrimination between cells of very similar
appearance. Normal-appearing intermediate cells from cases with normal cytology and those from patients with dysplasia or
malignant disease, as well as the subvisual markers within these cells that have rendered them capable of cytophotometric
discrimination, were used for the study. Comparison of the data recorded by the two systems indicates that the diagnostic
information is preserved in the change-over to a full-field, video-rate scanning system, with differences in the data caused
primarily by differences in the spectral response of the two systems. This was reflected in the substantial differences observed
in the color-related features and the lesser differences seen in the textural features, while the morphometric features (outline
and shape) were virtually unaffected. The differences were primarily expressed on a cell-to-cell basis; in sets of about 300
cells, which would be used in patient-to-patient comparisons, the feature values showed remarkable consistency between the
two systems. 相似文献
145.
Litao Zheng 《Journal of cellular and molecular medicine》2023,27(16):2271-2277
The hepatitis B virus (HBV) is considered one of the main driving forces in the development of hepatocellular carcinoma (HCC). Human HBV is a partially double-stranded DNA (dsDNA) virus consisting of approximately 3.2 kbp. HBV predominantly infects hepatocytes via the receptor sodium taurocholate cotransporting polypeptide (NTCP) and coreceptor hepatic proteoglycan. The replication of HBV in hepatocytes leads to apoptosis while simultaneously leading to cirrhosis and cancer. Although the integration of dsDNA into the hepatocyte genome seems to be the main cause of mutation, since the discovery of their function, viral proteins have been shown to regulate the P53 pathway or P13K/AKT pathway to prevent host cell apoptosis, causing uncontrolled proliferation of liver cells leading to the formation of solid tumours. The most common treatments involve nucleo(s)tide analogue (NA) and polyethylene glycol (PEG)ylated interferon-alpha (PegIFN-α). NA treatment has been found to be effective for the majority of patients and induces few side effects. Nevertheless, the rate of seroconversion is relatively low. PegIFN treatment is contraindicated during pregnancy and leads to a higher morbidity rate, but the seroconversion rate is high. Since medicines and vaccines have been developed, the incidence and mortality of HBV related to HCC have profoundly decreased compared to those in 2000. This review investigates what can be the potential mechanism that HBV can cause HBV and the treatment used in chronic and acute infection. 相似文献
146.
Chengwei Wu Song Wang Tingting Cao Tao Huang Lishuai Xu Jiawei Wang Qian Li Ye Wang Long Qian Li Xu Yabin Xia Xiaoxu Huang 《Journal of cellular and molecular medicine》2023,27(12):1609-1620
Proteins produced by cap-independent translation mediated by an internal ribosome entry site (IRES) in circular RNAs (circRNAs) play important roles in tumour progression. To date, numerous studies have been performed on circRNAs and the proteins they encode. In this review, we summarize the biogenesis of circRNAs and the mechanisms regulating circRNA-encoded proteins expression. We also describe relevant research methods and their applications to biological processes such as tumour cell proliferation, metastasis, epithelial-mesenchymal transition (EMT), apoptosis, autophagy and chemoresistance. This paper offers deeper insights into the roles that circRNA-encoded proteins play in tumours. It also provides a theoretical basis for the use of circRNA-encoded proteins as biomarkers of tumorigenesis and for the development of new targets for tumour therapy. 相似文献
147.
The effect of selenium on cell proliferation in liver and colon 总被引:2,自引:0,他引:2
Margaret A. Tempero Eleanor E. Deschner Morris S. Zedeck 《Biological trace element research》1986,10(2):145-152
Epidemiologic and experimental evidence support a chemoprotective role for selenium (Se) in malignancy. Many mechanisms have
been proposed to explain this phenomenon. In this study, the effect of Se intake on proliferation of hepatocytes and normal
colonic epithelial cells in rats was determined using autoradiographic analysis of thymidine incorporation into DNA. Hepatocyte
proliferation was measured 24 h after partial hepatectomy. Selenium-dosed animals demonstrated a significant reduction in
hepatocyte labeling compared to the control group (6.1±2.6 vs 29.2±15.6,p=0.003). However, Se dosing did not affect the thymidine-labeling indices or distribution of labeling in colonic epithelium.
Selenium may inhibit cell proliferation when it is the result of an unusually intense stimulus. This finding could explain
in part the inhibitory effect of Se in some experimental cancer models.
Dr. Tempero is a recipient of a Junior Clinical Faculty Fellowship from the American Cancer Society. 相似文献