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1.
Summary: Lymphatic filarial infection, from an immunologic point of view, is one of the most complex parasite infections. Not only are there different clinical manifestations that reflect differing immune responses, but the parasite's multiple stages, each with distinct anatomic tropism, add a compartmental layer of complexity to an already complicated process. Moreover, these parasites have finely tuned immune evasion strategies that enable escape from the innate immune system. As different stages of the parasite interact with different types of antigen‐presenting cells that, in turn, may play a significant role in shaping the subsequent adaptive immune response, the focus of this review is to provide insight into the interaction between filarial parasites and antigen‐presenting cells with an eye toward understanding how they influence parasite antigen‐driven T‐cell responses. 相似文献
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Ming-Cheng Luo Yong Q. Gu Frank M. You Karin R. Deal Yaqin Ma Yuqin Hu Naxin Huo Yi Wang Jirui Wang Shiyong Chen Chad M. Jorgensen Yong Zhang Patrick E. McGuire Shiran Pasternak Joshua C. Stein Doreen Ware Melissa Kramer W. Richard McCombie Shahryar F. Kianian Mihaela M. Martis Klaus F. X. Mayer Sunish K. Sehgal Wanlong Li Bikram S. Gill Michael W. Bevan Hana ?imková Jaroslav Dole?el Song Weining Gerard R. Lazo Olin D. Anderson Jan Dvorak 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(19):7940-7945
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Mohammad Reza Raoufy Shahryar Gharibzadeh Reza Abbasifar Behrad Radmehr Afshin Akhondzadeh Basti Arash Abbasifar Ramin Khaksar 《Comparative clinical pathology》2011,20(5):507-512
Salmonella is the most important cause of bacterial food-borne disease outbreaks in the world. In this study, we have trained and validated
artificial neural networks (ANNs) to predict the combined effect of Zataria multiflora essential oil (EO), pH, and temperature on the probability percentage of growth initiation (log P%) of Salmonella. Z. multiflora was collected in the Fars province of Iran. Lyophilized cultures of Salmonella typhimurium ATCC 25923 was used in this study. This design included four levels of EO (0.0, 0.015, 0.03, and 0.06%), three levels of
pH (5.5,6, and 7.3), three storage temperatures (35, 25, and 15°C), and repeated observations (18 times) for growth in brain
heart infusion broth for up to 43 days. We have designed a standard and the so-called feed-forward ANN, including four input
neurons, eight neuron in hidden layer, and one output neuron to predict the combined effect of Z. multiflora EO, pH, and temperature on the probability percentage of growth initiation (log P%) of S.typhimurium. The mean and standard deviation of ANN and real outputs were −2.9771 ± 2.43 and −2.9722 ± 2.39, respectively. The mean differences
(and 95% CIs) between the ANN and real outputs were 0.0049 (0.0009–0.0089). Result showed better prediction compare to the
previous study(R = 0.998). 相似文献
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To determine the association of serum apolipoprotein (apo) A-I and B concentrations, and paraoxonase (PON) high-density lipoprotein (HDL) associated enzyme activity with angiographically determined coronary artery disease (CAD) in Iranian diabetic and non-diabetic CAD patients and non-diabetic control subjects, 251 subjects aged 30-70 years, who underwent their first coronary angiography were matched and randomly assigned into three groups: CAD(+)DM(+), CAD(+)DM(-), and CAD(-)DM(-) (control). Stenosis of > or =50% in one or more coronary arteries was classified as CAD(+). CAD(-) was defined as a maximum stenosis of 10% in any coronary artery. Fasting serum concentrations of cholesterol (TC), triglycerides (TGs), LDL-C, HDL-C, apo A-I/B and PON activity were determined. Apolipoprotein concentrations were measured in a fasting serum sample by immunoturbidometric assay and paraoxonase/arylesterase activities by spectrophotometric assay of p-nitrophenol/phenol production following addition of paraoxon/phenylacetate. Information concerning non-lipid risk factors were collected by questionnaires. No significant difference was observed in HDL-C, LDL-C, apo A-I, and PON/arylesterase activity between the study groups. The values of TC (213+/-38 vs 196+/-45, P<0.05), TGs (209+/-187 vs 151+/-113, P<0.01), apo B (99+/-22 vs 96+/-24, P<0.0001), TC/HDL-C (4.8+/-1.5 vs 4.0+/-1.3, P<0.001) and LDL-C/HDL-C (2.9+/-1.1 vs 2.4+/-1.1, P<0.05) were higher and apo A-I/B (1.7+/-0.4 vs 2.0+/-0.6, P<0.01) was lower in CAD(+)DM(+) patients than in control subjects. In CAD(+)DM(-) group, only the level of apo B (96+/-24 vs 85+/-18, P<0.01), and the ratio of apo A-I/B (1.8+/-0.4 vs 2.0+/-0.6, P<0.01), were significantly higher than those of control group. On multiple logistic regression analysis, the best markers for discrimination between CAD(+) groups and CAD(-) control subjects were the ratio of apo A-I/B in diabetic and apo B in non-diabetic patients. The results suggest that in Iranian diabetic and non-diabetic patients with CAD the concentration of apolipoproteins are better markers than traditional lipid parameters in discriminating between CAD(+) and CAD(-) subjects. Lack of significant difference in PON activity between CAD patients and CAD(-) controls supports the concept of interethnic variability in PON polymorphism and unimodal distribution of its activity in non-Europid populations observed in other studies. 相似文献
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Fares S. Al-Qunaieer Hamid R. Tizhoosh Shahryar Rahnamayan 《Journal of digital imaging》2014,27(6):833-847
The level set approach to segmentation of medical images has received considerable attention in recent years. Evolving an initial contour to converge to anatomical boundaries of an organ or tumor is a very appealing method, especially when it is based on a well-defined mathematical foundation. However, one drawback of such evolving method is its high computation time. It is desirable to design and implement algorithms that are not only accurate and robust but also fast in execution. Bresson et al. have proposed a variational model using both boundary and region information as well as shape priors. The latter can be a significant factor in medical image analysis. In this work, we combine the variational model of level set with a multi-resolution approach to accelerate the processing. The question is whether a multi-resolution context can make the segmentation faster without affecting the accuracy. As well, we investigate the question whether a premature convergence, which happens in a much shorter time, would reduce accuracy. We examine multiple semiautomated configurations to segment the prostate gland in T2W MR images. Comprehensive experimentation is conducted using a data set of a 100 patients (1,235 images) to verify the effectiveness of the multi-resolution level set with shape priors. The results show that the convergence speed can be increased by a factor of ≈?2.5 without affecting the segmentation accuracy. Furthermore, a premature convergence approach drastically increases the segmentation speed by a factor of ≈?17.9. 相似文献
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Up Regulation of Liver-enriched Transcription Factors HNF4a and HNF6 and Liver-Specific MicroRNA (miR-122) by Inhibition of Let-7b in Mesenchymal Stem Cells 下载免费PDF全文
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Shahryar Semnani Mohammad Javad Kabir Sima Besharat Nafiseh Abdolahi Ahmad Danesh Danial Roshandel 《The Turkish journal of gastroenterology》2005,16(3):147-149
BACKGROUND/AIMS: Although a "hospital-based cancer registry" is important in improving patient care, a "population-based cancer registry" with emphasis on epidemiology is important in allocating health care resources and prioritizing public health programs. Because of its reliance on retrieved clinical and para-clinical documents, there is some limitation in registering all cancer incidents in this system, especially in developing countries. In this study we examined the possibility of using public data as a complementary source of information for recording cancers in a population-based cancer registry. METHODS: Along with the annual census in rural areas, a survey was performed in Golestan province in March 2004 to identify public awareness about cancer incidents in the community. Individuals were questioned about history of cancer in their close relatives during the last two years. Those who reported cancer in their relatives were also asked to name the main organ of involvement. A similar list was retrieved from the cancer registry at the Ministry of Health in Gorgan, and cases with upper GI (esophagus and gastric) cancer diagnosis from 21 March 2002 through 20 March 2004 were selected for this study. Finally, these two lists were compared for examining accuracy of the collected data. RESULTS: We included 137 cases in our study with rural residence and known addresses. Only 35 (25.5%) cases were reported by the relatives and among them only 20 (57.1%) relatives correctly reported the tumor location. Although we found a difference in accurate reporting of cancer incidents by year of diagnosis (more correct cases reported during the second versus the first year), the difference was not statistically significant between the two years. CONCLUSION: In this study, we examined the possibility of using public awareness about cancer incidents as a complementary source of information for a population-based cancer registry. We found that this approach is not ideal for reducing limitations. Therefore, we recommend a nationwide cancer registry to record all cancer-related information at the time of diagnosis. This strategy will reduce the need for performing retrospective surveys in collecting cancer-related information. 相似文献
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Effects of an alkylating anticancer drug, cyclophosphamide (Cp), on 23Na signal intensity (23Na SI) and water apparent diffusion coefficient (ADC) were examined in subcutaneously-implanted radiation-induced fibrosarcoma (RIF-1) tumors by 23Na and 1H magnetic resonance imaging (MRI). MRI experiments were performed on untreated control (n = 5) and Cp-treated (n = 6) C3H mice, once before Cp injection (300 mg/kg) then daily for 3 days after treatment. Tumor volumes were significantly lower in treated animals 2 and 3 days posttreatment. At the same time points, in vivo MRI experiments showed an increase in both 23Na SI and water ADC in treated tumors, whereas control tumors did not show any significant changes. The correlation between 23Na SI and water ADC changes was dramatically increased in the Cp-treated group, suggesting that the observed increases in 23Na SI and water ADC were caused by the same mechanism. Histologic sections showed decreased cell density in the regions of increased 23Na and water ADC SI. Destructive chemical analysis showed that Cp treatment increased the relative extracellular space and tumor [Na+]. We conclude that the changes in water ADC and 23Na SI were largely due to an increase in extracellular space. 23Na MRI and 1H water ADC measurements may provide valuable noninvasive techniques for monitoring chemotherapeutic responses. 相似文献