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排序方式: 共有374条查询结果,搜索用时 15 毫秒
1.
2.
The effect of bradykinin and its antagonist on survival time after coronary artery occlusion in hypertensive rats 总被引:1,自引:0,他引:1
It is known that BK does play a role in the cardioprotective effect of angiotensin converting enzyme (ACE) inhibitors. The present study therefore was conducted to examine the effects of bradykinin (BK) and its antagonist on survival time in spontaneously hypertensive rats (SHR) with coronary artery ligation for 15 min and continuously. We also evaluated the heart rate and blood pressure (BP) in the presence and absence of BK and BK2 receptor antagonist, D-Arg-[Hyp-D-Phe7]BK. Coronary artery was ligated in anaesthetized rats and they were artificially ventilated with room air (stroke volume, 4 ml; 48 strokes/min) as described by the previous investigators. Lead II elecrocardiogram (ECG) was recorded from subcutaneous steel needle electrodes. Results of this investigation indicated that BK treatment 4 microg/kg (i.v.) and 8 microg/kg (i.v.) caused significant (P < 0.05) increase in survival time in SHR with coronary artery ligation for 15 min and continuously as compare to their respective saline-treated controls. However, BK antagonist treatment 4 microg/kg (i.v.) abolished the increase in survival time caused by BK treatment. The mean values of survival time between the saline-treated and BK antagonist plus BK-treated rats did not differ significantly (P > 0.05). The heart rate and BP responses were greatly reduced (P < 0.001) in the presence of coronary artery ligation. These findings suggest that BK might have cardioprotective effect to increase the survival time in rats by activating BK2 receptors after coronary artery ligation. 相似文献
3.
Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
4.
M. M. Quazi M. Ishak A. Arslan M. A. Fazal Farazila Yusof B. S. Sazzad M. Nasir Bashir M. Jamshaid 《RSC advances》2018,8(13):6858
Laser composite surfacing (LCS) is a photon driven manufacturing technology that can be utilized for depositing hybrid metal matrix composite coatings (HMMC) on softer Ti/Al/Mg alloys to enhance their tribo-mechanical properties. LCS offers the advantages of higher directionality, localized microstructural refinement and higher metallurgical bonding between coating and substrate. The current research presents the tribo-mechanical evaluation and characterization of solid lubricant based Ni–WC coatings deposited by LCS on Al–Si piston alloy by varying the concentration of graphite between 5-to-15-weight percentage. The tribological behavior of LCS samples was investigated using a ball-on-plate tribometer. Results indicate that the surface hardness, wear rate and friction coefficient of the Al–Si hypereutectic piston alloy were improved after LCS of graphite based HMMC coatings. The maximum surface hardness of 781Hv was acquired for the Ni–WC coating containing 5 wt% graphite. The friction coefficient of Al–Si under dry sliding conditions was reduced from 0.47 to 0.21. The reduction in the friction coefficient was attributed to the formation of a shearable transfer layer, which prevented delamination and reduced adhesion, abrasion and fatigue cracking.The addition of graphite as solid lubricant has significantly reduced the friction coefficient and wear of a Ni–WC composite coating. 相似文献
5.
Fara Wahida Rezali Yit Siew Chin Zalilah Mohd Shariff Barakatun Nisak Mohd Yusof Kaartina Sanker Fui Chee Woon 《Nutrition Research And Practice》2015,9(5):511-516
BACKGROUND/OBJECTIVES
This study aims to determine contribution of meal frequency, self-efficacy for healthy eating, and availability of healthy foods towards diet quality of adolescents in Kuala Lumpur, Malaysia.SUBJECTS/METHODS
This study was conducted among 373 adolescents aged from 13 to 16 years old. Diet quality of the respondents was assessed using the Healthy Eating Index for Malaysians. Meal frequency, self-efficacy for healthy eating, and availability of healthy foods were assessed through the Eating Behaviours Questionnaire (EBQ), self-efficacy for healthy eating scale, and availability of healthy foods scale, respectively.RESULTS
The majority of the respondents (80.7%) were at risk of poor diet quality. Males (mean = 34.2 ± 8.2%) had poorer diet quality than females (mean = 39.9 ± 9.0%) (t = -5.941, P < 0.05). Malay respondents (mean = 36.9 ± 8.7%) had poorer diet quality than Indian respondents (mean = 41.3 ± 10.0%) (F = 2.762, P < 0.05). Age (r = 0.123, P < 0.05), self-efficacy for healthy eating (r = 0.129, P < 0.05), and availability of healthy foods (r = 0.159, P < 0.05) were positively correlated with the diet quality of the respondents. However, meal frequency was not correlated with the diet quality of the respondents. Multiple linear regression analysis showed that being a male, being a Malay, low self-efficacy for healthy eating, and low availability of healthy foods contributed significantly towards poor diet quality among respondents.CONCLUSIONS
In short, sex, ethnicity, self-efficacy for healthy eating, and availability of healthy foods were associated with diet quality among adolescents. Health practitioners should take into consideration of differences in sex and ethnicity during implementation of nutrition-related intervention programs. Self-efficacy for healthy eating and availability of healthy foods should be included as important components in improving diet quality of adolescents. 相似文献6.
Norzila Kusnin Nor Azah Yusof Jaafar Abdullah Suriana Sabri Faruq Mohammad Shuhaimi Mustafa Nurul Asyikeen Ab Mutalib Shinobu Sato Shigeori Takenaka Nor Azizah Parmin Hamad A. Al-Lohedan 《RSC advances》2020,10(46):27336
In this study, an electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles (SiNWs/PtNPs) on a screen-printed carbon electrode (SPCE) for the detection of Sus scrofa mitochondrial DNA (mtDNA) in food utilizing a new hybrid indicator, ferrocenylnaphthalene diimide (FND). The morphology and elemental composition of the SiNWs/PtNPs-modified SPCE was analyzed by field emission scanning electron microscopy (FESEM) combined with energy dispersive X-ray spectroscopy (EDX). Cyclic voltammetry (CV) was used to study the electrical contact between the PtNPs and the screen-printed working electrode through SiNWs, while electrochemical impedance spectroscopy (EIS) was used to measure the charge transfer resistance of the modified electrode. The results clearly showed that the SiNWs/PtNPs were successfully coated onto the electrode and the effective surface area for the SiNWs/PtNPs-modified SPCE was increased 16.8 times as compared with that of the bare SPCE. Differential pulse voltammetry used for the detection of porcine DNA with FND as an intercalator confirmed its specific binding to the double-stranded DNA (dsDNA) sequences. The developed biosensor showed a selective response towards complementary target DNA and was able to distinguish non-complementary and mismatched DNA oligonucleotides. The SiNWs/PtNPs-modified SPCE that was fortified with DNA hybridization demonstrated good linearity in the range of 3 × 10−9 M to 3 × 10−5 M (R2 = 0.96) with a detection limit of 2.4 × 10−9 M. A cross-reactivity study against various types of meat and processed food showed good reliability for porcine samples.An electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles on a screen-printed carbon electrode for the detection of Sus scrofa mitochondrial DNA in food. 相似文献
7.
Genomic organization of alpha1 and beta1 subunits of the mammalian soluble guanylyl cyclase genes
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Sharina IG Krumenacker JS Martin E Murad F 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(20):10878-10883
The structures of the genes encoding the alpha(1) and beta(1) subunits of murine soluble guanylyl cyclase (sGC) were determined. Full-length cDNAs isolated from mouse lungs encoding the alpha(1) (2.5 kb) and beta(1) (3.3 kb) subunits are presented in this report. The alpha(1) sGC gene is approximately 26.4 kb and contains nine exons, whereas the beta(1) sGC gene spans 22 kb and consists of 14 exons. The positions of exon/intron boundaries and the sizes of introns for both genes are described. Comparison of mouse genomic organization with the Human Genome Database predicted the exon/intron boundaries of the human genes and revealed that human and mouse alpha1 and beta1 sGC genes have similar structures. Both mouse genes are localized on the third chromosome, band 3E3-F1, and are separated by a fragment that is 2% of the chromosomal length. The 5' untranscribed regions of alpha(1) and beta(1) subunit genes were subcloned into luciferase reporter constructs, and the functional analysis of promoter activity was performed in murine neuroblastoma N1E-115 cells. Our results indicate that the 5' untranscribed regions for both genes possess independent promoter activities and, together with the data on chromosomal localization, suggest independent regulation of both genes. 相似文献
8.
Yaman Yousof Nosizana M. Salleh Farazila Yusof 《The Journal of prosthetic dentistry》2019,121(6):916-921
Statement of problemThe 2-color mixing ability test has been recently introduced for objective assessment of masticatory performance. However, the ideal bicolor specimens have not yet been identified, and the color analysis of digital images requires improvement.PurposeThe purpose of this clinical study was to formulate a custom-made, 2-color chewing gum for the mixing ability test and to develop an image-processing method for color mixing analysis.Material and methodsSpecimens of red-green (RG) chewing gum were prepared as a test food. Twenty dentate participants (10 men, 10 women; mean age 21 years) took part in this study. Each participant masticated 1 piece of RG gum for 3, 6, 9, 15, and 25 cycles, and this task was repeated 3 times consecutively (total n=15 for each participant). The boluses were retrieved and flattened to 1-mm-thick wafers and scanned with a flatbed scanner. The digital images were analyzed using ImageJ software equipped with a custom-built plug-in to measure the geometric dispersion (GD) of baseline red segment. The predictive criterion validity of this method was determined by correlating GD to the number of mastication cycles. The hardness and mass of RG chewing gum were measured before and after mastication. Hardness loss (%) and mass loss (%) were then calculated and compared with those of a commercially available chewing gum.ResultsThe 2-way repeated-measures ANOVA with post hoc Bonferroni test showed that GD was able to discriminate among the groups of different numbers of mastication cycles (P<.001). Pearson correlation coefficient confirmed the significant correlation between GD and the number of mastication cycles (r=0.90, P<.001). The hardness loss and mass loss of RG chewing gum were significantly lower than those of commercial chewing gum (P<.001).ConclusionsThe newly formulated chewing gum provides an appropriate test food material for masticatory performance assessment. The new image-processing method discriminated among the different levels of color mixture and quantified the mixing ability. 相似文献
9.
Viera AJ Lin FC Hinderliter AL Shimbo D Person SD Pletcher MJ Jacobs DR 《Hypertension》2012,59(6):1157-1163
Nighttime blood pressure (BP) dipping can be quantified as the ratio of mean nighttime (sleep) BP to mean daytime (awake) BP. People whose dipping ratio is ≥ 0.90 have been referred to as nondippers, and nondipping is associated with cardiovascular disease events. We examined the relationship between systolic nighttime BP dipping in young adults and the presence of coronary artery calcium (CAC) 10 to 15 years later using data from the ambulatory BP monitoring substudy of the Coronary Artery Risk Development in Young Adults Study. Among 239 participants with adequate measures of both nighttime and daytime readings and coronary artery calcium, the systolic BP dipping ratio ranged from 0.72 to 1.24 (mean, 0.88; SD, 0.06), and CAC was present 10 to 15 years later in 54 participants (22.6%). Compared with those whose systolic BP dipping ratio ranged from 0.88 to 0.92 (quartile 3), the 57 participants (23.9%) with less pronounced or absent dipping (ratio, 0.92-1.24; quartile 4) had an unadjusted odds ratio of 4.08 (95% CI, 1.48-11.2) for the presence of CAC. The 60 participants (25.1%) with a more pronounced dipping (ratio, 0.72-0.85; quartile 1) also had greater odds for presence of CAC (odds ratio, 4.76 [95% CI, 1.76-12.9]). When modeled as a continuous predictor, a U-shaped relationship between systolic BP dipping ratio and future CAC was apparent and persisted after adjustment for multiple potential confounders (P<0.001 for quadratic term). Both failure of systolic BP to dip sufficiently and "overdipping" during nighttime may be associated with future subclinical coronary atherosclerosis. 相似文献
10.
Abdullah MH Othman Z Noor HM Arshad SS Yusof AK Jamal R Rahman AR 《Journal of cardiology》2012,60(3):192-203
The molecular basis of coronary artery disease (CAD) has been widely studied in the western world but there is no published work on the Malaysian population. This study looked at the global gene expression profiling of the peripheral blood of patients with CAD from the 3 main ethnic groups in Malaysia. Male subjects selected were based on angiographically confirmed CAD (≥50% stenosis) and normal control subjects (0% stenosis) with age range of 55.6±5.3 and 51.0±5.5years, respectively. The global gene expression of 12 angiographically documented CAD patients and 11 matched control subjects were performed. The combined group samples identified 6 up regulated differential expression (DE) genes (GHRL, LTA, CBS, HP, ITGA2B, and OLR1) and 12 down regulated DE genes (IL18R1, ITGA2B, IL18RAP, HP, OLR1, SOD2 ITGB3, IL1B, MMP9, PLA2G7, UTS2, and CBS) to be involved in CAD at the fold change of 1.3 with fault discovery rate (FDR) of 1%. Three genes, MMP9, IL1B, and SOD2 were down regulated in all the 3 ethnic groups making them potential biomarker candidates for CAD across all three ethnicities. Further verification in a cohort study is needed. 相似文献