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排序方式: 共有6125条查询结果,搜索用时 187 毫秒
131.
Rong Qiu Jingwei Li Yuxuan Xiao Ziyi Gao Yihang Weng Qiran Zhang Chengdi Wang Hanlin Gong Weimin Li 《Medicine》2021,100(16)
Background:Coronavirus disease 2019 (COVID-19) has spread almost all regions of the world and caused great loss to the whole body of mankind. Thus, numerous clinical trials were conducted to find specific medicine for COVID-19 recently. However, it remains unanswered whether they are beneficial.Objective:This study aimed to evaluate the efficiency and safety of the COVID-19 medicine.Methods:Studies were determined through searching PubMed, Embase, Cochrane Library, and Medline. The studies of COVID-19 medicine were involved with eligible end points containing mortality, discharge rate, rate of clinical improvement, and rate of serious adverse events.Results:A total of 33 studies involving 37,879 patients were included in our study, whose intervening measures contained three major types of COVID-19 medicine, ACEI/ARB, antiviral medicine, and chloroquine/hydroxychloroquine. Compared to control group, COVID-19 drugs have no distinct effect on mortality (RR, 0.93; 95% CI, 0.79–1.11, P = .43) and discharge rate (RR, 1.06; 95% CI, 0.98–1.14, P = .13). However, antiviral medicine presents the obvious advantage in clinical improvement (RR, 1.11; 95% CI, 1.01–1.23, P < .05). In addition, the serious adverse events rate (RR, 0.75; 95% CI, 0.63–0.88, P < .05) of COVID-19 medicine is lower than control group.Conclusion:The results indicated antiviral medicine was potential specific medicine for COVID-19 treatment by improving clinical symptoms, but it failed to increase the discharge rate and reduce mortality. Chloroquine/hydroxychloroquine and ACEI/ARB had no significant effect on treatment of COVID-19, thus they were not recommended for routine medication. Moreover, more trials are needed to find effective drugs to lower the mortality of COVID-19 patients. 相似文献
132.
Alpha‐phellandrene‐induced DNA damage and affect DNA repair protein expression in WEHI‐3 murine leukemia cells in vitro 下载免费PDF全文
Jen‐Jyh Lin Chih‐Chung Wu Shu‐Chun Hsu Shu‐Wen Weng Yi‐Shih Ma Yi‐Ping Huang Jaung‐Geng Lin Jing‐Gung Chung 《Environmental toxicology》2015,30(11):1322-1330
Although there are few reports regarding α‐phellandrene (α‐PA), a natural compound from Schinus molle L. essential oil, there is no report to show that α‐PA induced DNA damage and affected DNA repair associated protein expression. Herein, we investigated the effects of α‐PA on DNA damage and repair associated protein expression in murine leukemia cells. Flow cytometric assay was used to measure the effects of α‐PA on total cell viability and the results indicated that α‐PA induced cell death. Comet assay and 4,6‐diamidino‐2‐phenylindole dihydrochloride staining were used for measuring DNA damage and condensation, respectively, and the results indicated that α‐PA induced DNA damage and condensation in a concentration‐dependent manner. DNA gel electrophoresis was used to examine the DNA damage and the results showed that α‐PA induced DNA damage in WEHI‐3 cells. Western blotting assay was used to measure the changes of DNA damage and repair associated protein expression and the results indicated that α‐PA increased p‐p53, p‐H2A.X, 14‐3‐3‐σ, and MDC1 protein expression but inhibited the protein of p53, MGMT, DNA‐PK, and BRCA‐1. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1322–1330, 2015. 相似文献
133.
Weng SW Liou CW Lin TK Wei YH Lee CF Eng HL Chen SD Liu RT Chen JF Chen IY Chen MH Wang PW 《The Journal of clinical endocrinology and metabolism》2005,90(9):5037-5040
OBJECTIVE: A common variant in mitochondrial DNA (mtDNA) at bp 16189 (T-->C transition) has been associated with small birth size, adulthood hyperglycemia, and insulin resistance in Caucasians. In this study, we investigated whether mtDNA 16189 variant is associated with metabolic syndrome in Chinese subjects. METHODS: Six hundred fifteen Chinese adults, aged 40 yr or older, were recruited in this study. The 16189 variant of mtDNA was detected using PCR and restriction enzyme digestion. Metabolic syndrome was diagnosed on modified National Cholesterol Education Program Adult Treatment Panel III guidelines, using body mass index (BMI) instead of waist circumference. An association study was performed with chi2 test and logistic regression analysis. RESULTS: The prevalence of the 16189 variant was higher in patients with metabolic syndrome than in those without: 44% (125 of 284) vs. 33.2% (110 of 331) (P = 0.006). The association between this 16189 variant of mtDNA and metabolic syndrome (P = 0.021) remained significant even after correcting for age and BMI. As to the individual traits, the prevalence of fasting plasma glucose of at least 110 mg/dl (> or =6.1 mmol/liter) [(51.5% (121 of 235) vs. 42.1% (160 of 380); P = 0.023], type 2 diabetes mellitus [48.1% (113 of 235) vs. 39.2% (149 of 380); P = 0.031], and hypertriglyceridemia [44.3% (104 of 235) vs. 35.8% (136 of 380); P = 0.037] were significantly higher in subjects harboring the 16189 variant of mtDNA than those with the wild type. However, the prevalence of hypertension [53.2% (125 of 235) vs. 47.6% (181 of 380); P = 0.180], BMI greater than 25 kg/m2 [48.5% (114 of 235) vs. 43.9% (167 of 380); P = 0.270], and low high-density lipoprotein cholesterol [61.3% (144 of 235) vs. 54.7% (208 of 380); P = 0.111] did not reach a significant difference between the two groups. Furthermore, there was a trend of increasing frequency of occurrence of the 16189 variant in individuals having an increasing number of components of metabolic syndrome (Ptrend < 0.005). CONCLUSION: Our data strongly suggest that mtDNA 16189 variant underlies susceptibility to metabolic syndrome in the Chinese population. 相似文献
134.
Gen Zhang Liang Wu Aitao Tang Bo Weng Andrej Atrens Shida Ma Lei Liu Fusheng Pan 《RSC advances》2018,8(5):2248
In this work, anodized magnesium alloy AZ31 with and without boiling water sealing was pre-prepared, and then MgAl-layered double hydroxide (LDH) films were fabricated on it through hydrothermal chemical conversion of the pre-prepared anodic layer. The morphology, structure, and composition of the films were characterized by XRD, SEM, EDS, FT-IR, XPS and GDOES. It was found that the porosity of the films was reduced after in situ fabrication of the LDHs. The effects of boiling water sealing treatment on the anodized substrate were also discussed. Moreover, the polarization curve, EIS, and immersion tests showed that LDHs fabricated on the anodized substrate with boiling water sealing treatment exhibited a significant long period of protection for the substrate.In this work anodized magnesium alloy AZ31 with and without boiling water sealing was pre-prepared, and then MgAl-layered double hydroxide (LDH) films were fabricated on it through hydrothermal chemical conversion of the pre-prepared anodic layer. 相似文献
135.
The corrosion of NiCrMoV steel welded joints is performed in an aqueous solution of 3.5 wt% NaCl at 180 °C in a container at a pressure of 0.8 MPa. The specimens in the shape of cylindrical tensile rods are immersed in the aqueous solution under the action of tensile stress in a range of 0 to 0.9 of the yield stress of the base metal. The experimental results suggest that there is macro-galvanic corrosion in the welded joint with the coarse-grained heat affected zone (CGHAZ) as anode due to the highest corrosion susceptibility of the CGHAZ. The CGHAZ has the highest positive current density in the welded joints as measured by the scanning vibrating electrode technique. The two-parameter Weibull distribution function, which is represented by the Weibull modulus and characteristic strength, is used to analyze the distribution of the depth of pits at different immersion times. Both the Weibull modulus and characteristic strength are calculated, and found to be dependent on the applied tensile stress. The values of the characteristic pit depth and the average pit depth reveal that there are two mechanisms controlling the corrosion of the NiCrMoV steel welded joints; one is galvanic corrosion, and the other is stress-assisted corrosion.Pit evolution around the fusion line of a welded joint caused by galvanic and stress-assisted coupling corrosion has been investigated. 相似文献
136.
137.
138.
Optimal treatment allocation for placebo‐treatment comparisons in trials with discrete‐time survival endpoints 下载免费PDF全文
In many randomized controlled trials, treatment groups are of equal size, but this is not necessarily the best choice. This paper provides a methodology to calculate optimal treatment allocations for longitudinal trials when we wish to compare multiple treatment groups with a placebo group, and the comparisons may have unequal importance. The focus is on trials with a survival endpoint measured in discrete time. We assume the underlying survival process is Weibull and show that values for the parameters in the Weibull distribution have an impact on the optimal treatment allocation scheme in an interesting way. Additionally, we incorporate different cost considerations at the subject and measurement levels and determine the optimal number of time periods. We also show that when many events occur at the beginning of the trial, fewer time periods are more efficient. As an application, we revisit a risperidone maintenance treatment trial in schizophrenia and use our proposed methodology to redesign it and compare merits of our optimal design. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
139.
C Y Hsu R S Sulake P-K Huang H-Y Shih H-W Sie Y-K Lai C Chen C F Weng 《British journal of pharmacology》2015,172(1):38-49
BACKGROUND AND PURPOSE
The fungal product (+)-antroquinonol activates AMP kinase (AMPK) activity in cancer cell lines. The present study was conducted to examine whether chemically synthesized (+)-antroquinonol exhibited beneficial metabolic effects in insulin-resistant states by activating AMPK and inhibiting dipeptidyl peptidase IV (DPP IV) activity.EXPERIMENTAL APPROACH
Effects of (+)-antroquinonol on DPP IV activity were measured with a DPPIV Assay Kit and effects on GLP-1-induced PKA were measured in AR42J cells. Translocation of the glucose transporter 4, GLUT4, induced either by insulin-dependent PI3K/AKT signalling or by insulin-independent AMPK activation, was assayed in differentiated myotubes. Glucose uptake and GLUT4 translocation were assayed in L6 myocytes. Mice with diet-induced obesity were used to assess effects of acute and chronic treatment with (+)-antroquinonol on glycaemic control in vivo.KEY RESULTS
The results showed that of (+)-antroquinonol (100 μM ) inhibited the DPP IV activity as effectively as the clinically used inhibitor, sitagliptin. The phosphorylation of AMPK Thr172 in differentiated myotubes was significantly increased by (+)-antroquinonol. In cells simultaneously treated with S961 (insulin receptor antagonist), insulin and (+)-antroquinonol, the combination of (+)-antroquinonol plus insulin still increased both GLUT4 translocation and glucose uptake. Further, (+)-antroquinonol and sitagliptin reduced blood glucose, when given acutely or chronically to DIO mice.CONCLUSIONS AND IMPLICATIONS
Chemically synthesized (+)-antroquinonol exhibits dual effects to ameliorate insulin resistance, by increasing AMPK activity and GLUT4 translocation, along with inhibiting DPP IV activity. 相似文献140.
In this study, fluorescence of self-assembled multilayers (SAMs) of carbon dots (CDs) was found to be enhanced by graphene. The number of polyelectrolyte layers can be tuned to control the distance between CDs and graphene in SAMs. The enhanced fluorescence efficiency was found to be dependent on graphene concentration, degree of graphene reduction, and the distance between CDs and graphene surface. When graphene concentration and polyelectrolyte bilayer number were set to 0.005 mg mL−1 and 3 layers, respectively, fluorescence intensity of CDs could be increased up to 3.2 times. Tetracycline hydrochloride (Tc) could be detected by the established SAMs in the presence of graphene as the sensitivity was 2 orders higher than that of SAMs in the absence of graphene. Limit of detection of this sensing system was 0.9284 nM, which is 1–3 orders of magnitude lower than those of most of reported fluorescence sensors. This method could be successfully applied to detect trace Tc in milk samples.The fluorescence of carbon dots self-assembled multilayers (CDs SAMs) can be enhanced by graphene, the sensing sensitivity for tetracycline hydrochloride of CDs SAMs with graphene is two orders higher than that of SAMs without graphene. 相似文献