全文获取类型
收费全文 | 145042篇 |
免费 | 10850篇 |
国内免费 | 4231篇 |
专业分类
耳鼻咽喉 | 742篇 |
儿科学 | 3492篇 |
妇产科学 | 3210篇 |
基础医学 | 14134篇 |
口腔科学 | 2124篇 |
临床医学 | 18264篇 |
内科学 | 19500篇 |
皮肤病学 | 1586篇 |
神经病学 | 8225篇 |
特种医学 | 5061篇 |
外国民族医学 | 11篇 |
外科学 | 10461篇 |
综合类 | 25284篇 |
现状与发展 | 10篇 |
一般理论 | 8篇 |
预防医学 | 12820篇 |
眼科学 | 2670篇 |
药学 | 14989篇 |
253篇 | |
中国医学 | 12392篇 |
肿瘤学 | 4887篇 |
出版年
2024年 | 406篇 |
2023年 | 2112篇 |
2022年 | 3944篇 |
2021年 | 5900篇 |
2020年 | 5210篇 |
2019年 | 4473篇 |
2018年 | 4414篇 |
2017年 | 4635篇 |
2016年 | 4754篇 |
2015年 | 4568篇 |
2014年 | 8632篇 |
2013年 | 9941篇 |
2012年 | 8143篇 |
2011年 | 8810篇 |
2010年 | 6993篇 |
2009年 | 6320篇 |
2008年 | 6403篇 |
2007年 | 6618篇 |
2006年 | 5906篇 |
2005年 | 5322篇 |
2004年 | 4642篇 |
2003年 | 4446篇 |
2002年 | 3632篇 |
2001年 | 3404篇 |
2000年 | 2807篇 |
1999年 | 2528篇 |
1998年 | 2277篇 |
1997年 | 2364篇 |
1996年 | 1987篇 |
1995年 | 1909篇 |
1994年 | 1742篇 |
1993年 | 1400篇 |
1992年 | 1350篇 |
1991年 | 1205篇 |
1990年 | 1081篇 |
1989年 | 968篇 |
1988年 | 885篇 |
1987年 | 730篇 |
1986年 | 729篇 |
1985年 | 996篇 |
1984年 | 887篇 |
1983年 | 562篇 |
1982年 | 756篇 |
1981年 | 579篇 |
1980年 | 563篇 |
1979年 | 420篇 |
1978年 | 339篇 |
1977年 | 314篇 |
1976年 | 290篇 |
1975年 | 182篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
青岛大学附属烟台毓璜顶医院生殖医学中心对1例反复体外受精/卵细胞质内单精子注射(IVF/ICSI)助孕后早期胚胎发育停滞的患者进行了全外显子基因检测,发现了一种新的TUBB8基因突变型(c.208C>T/p.Pro70Ser),并进一步探讨了TUBB8基因突变与早期胚胎发育停滞之间的联系,为反复种植失败的诊断与治疗提供更多可能性。 相似文献
992.
《Obesity research & clinical practice》2021,15(6):546-556
PurposeThis systematic review aimed to investigate the association between VAI and blood pressure.MethodsThe study was according to the PRISMA standards and the bibliographic search in the PubMed, EMBASE and Cochrane Library databases.ResultsThis review included 32 articles, with 60,482 individuals – children to elderly people between 7 and 102 years old – of different age groups, most of them female (54.9%; n = 26,478). The year of publication ranged from 2010 to 2020, indicating that it is a recent theme, applied in almost all continents (America, Europe, Africa and Asia). The authors used data as continuous or into quantiles; blood pressure data also varied, with different cutoff points for the classification of arterial hypertension or continuously. The vast majority of studies have shown a positive association between VAI and blood pressure, both the sexes, in different age groups. The evaluation of the quality of the articles used by the Tool of the Joanna Briggs Institute according to their design.ConclusionIndividuals with increased VAI have higher blood pressure levels. Registration (PROSPERO: CRD42020205965). 相似文献
993.
Stephanie Andraos Beatrix Jones Clare Wall Eric Thorstensen Martin Kussmann David Cameron-Smith Katherine Lange Susan Clifford Richard Saffery David Burgner Melissa Wake Justin OSullivan 《Nutrients》2021,13(3)
Scope: B vitamers are co-enzymes involved in key physiological processes including energy production, one-carbon, and macronutrient metabolism. Studies profiling B vitamers simultaneously in parent–child dyads are scarce. Profiling B vitamers in parent–child dyads enables an insightful determination of gene–environment contributions to their circulating concentrations. We aimed to characterise: (a) parent–child dyad concordance, (b) generation (children versus adults), (c) age (within the adult subgroup (age range 28–71 years)) and (d) sex differences in plasma B vitamer concentrations in the CheckPoint study of Australian children. Methods and Results: 1166 children (11 ± 0.5 years, 51% female) and 1324 parents (44 ± 5.1 years, 87% female) took part in a biomedical assessment of a population-derived longitudinal cohort study: The Growing Up in Australia’s Child Health CheckPoint. B vitamer levels were quantified by UHPLC/MS-MS. B vitamer levels were weakly concordant between parent–child pairs (10–31% of variability explained). All B vitamer concentrations exhibited generation-specificity, except for flavin mononucleotide (FMN). The levels of thiamine, pantothenic acid, and 4-pyridoxic acid were higher in male children, and those of pantothenic acid were higher in male adults compared to their female counterparts. Conclusion: Family, age, and sex contribute to variations in the concentrations of plasma B vitamers in Australian children and adults. 相似文献
994.
Modification of the Lipid Profile of the Initial Oral Biofilm In Situ Using Linseed Oil as Mouthwash
Lipids are of interest for the targeted modification of oral bioadhesion processes. Therefore, the sustainable effects of linseed oil on the composition and ultrastructure of the in situ pellicle were investigated. Unlike saliva, linseed oil contains linolenic acid (18:3), which served as a marker for lipid accumulation. Individual splints with bovine enamel slabs were worn by five subjects. After 1 min of pellicle formation, rinses were performed with linseed oil for 10 min, and the slabs’ oral exposure was continued for up to 2 or 8 h. Gas chromatography coupled with electron impact ionization mass spectrometry (GC-EI/MS) was used to characterize the fatty acid composition of the pellicle samples. Transmission electron microscopy was performed to analyze the ultrastructure. Extensive accumulation of linolenic acid was recorded in the samples of all subjects 2 h after the rinse and considerable amounts persisted after 8 h. The ultrastructure of the 2 h pellicle was less electron-dense and contained lipid vesicles when compared with controls. After 8 h, no apparent ultrastructural effects were visible. Linolenic acid is an excellent marker for the investigation of fatty acid accumulation in the pellicle. New preventive strategies could benefit from the accumulation of lipid components in the pellicle. 相似文献
995.
Energy drinks containing significant quantities of caffeine, taurine and sugar are increasingly consumed, particularly by adolescents and young adults. The putative effects of chronic ingestion of either standard energy drink, MotherTM (ED), or its sugar-free formulation (sfED) on metabolic syndrome were determined in wild-type C57BL/6J mice, in comparison to a soft drink, Coca-Cola (SD), a Western-styled diet enriched in saturated fatty acids (SFA), and a combination of SFA + ED. Following 13 weeks of intervention, mice treated with ED were hyperglycaemic and hypertriglyceridaemic, indicating higher triglyceride glucose index, which was similar to the mice maintained on SD. Surprisingly, the mice maintained on sfED also showed signs of insulin resistance with hyperglycaemia, hypertriglyceridaemia, and greater triglyceride glucose index, comparable to the ED group mice. In addition, the ED mice had greater adiposity primarily due to the increase in white adipose tissue, although the body weight was comparable to the control mice receiving only water. The mice maintained on SFA diet exhibited significantly greater weight gain, body fat, cholesterol and insulin, whilst blood glucose and triglyceride concentrations remained comparable to the control mice. Collectively, these data suggest that the consumption of both standard and sugar-free forms of energy drinks induces metabolic syndrome, particularly insulin resistance. 相似文献
996.
Ji-Hye Song Hyunhee Kim Minseok Jeong Min Jung Kong Hyo-Kyoung Choi Woojin Jun Yongjae Kim Kyung-Chul Choi 《Nutrients》2021,13(5)
Metabolic syndrome is a worldwide health problem, and obesity is closely related to type 2 diabetes, cardiovascular disease, hypertension, and cancer. According to WHO in 2018, the prevalence of obesity in 2016 tripled compared to 1975. D. morbifera reduces bad cholesterol and triglycerides levels in the blood and provides various antioxidant nutrients and germicidal sub-stances, as well as selenium, which helps to remove active oxygen. Moreover, D. morbifera is useful for treating cardiovascular diseases, hypertension, hyperlipidemia, and diabetes. Therefore, we study in vivo efficacy of D. morbifera to investigate the prevention effect of obesity and cholesterol. The weight and body fat were effectively reduced by D. morbifera water (DLW) extract administration to high-fat diet-fed C57BL/6 mice compared to those of control mice. The group treated with DLW 500 mg∙kg−1∙d−1 had significantly lower body weights compared to the control group. In addition, High-density lipoprotein (HDL) cholesterol increased in the group treated with DLW 500 mg∙kg−1∙d−1. The effect of DLW on the serum lipid profile could be helpful to prevent obesity. DLW suppresses lipid formation in adipocytes and decreases body fat. In conclusion, DLW can be applied to develop anti-obesity functional foods and other products to reduce body fat. 相似文献
997.
Anne Daly Wolfgang Hgler Nicola Crabtree Nick Shaw Sharon Evans Alex Pinto Richard Jackson Catherine Ashmore Júlio C. Rocha Boyd J. Strauss Gisela Wilcox William D. Fraser Jonathan C. Y. Tang Anita MacDonald 《Nutrients》2021,13(6)
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs. 相似文献
998.
Yutaka Inoue Yukari Kitani Satoshi Osakabe Yukitoshi Yamamoto Isamu Murata Ikuo Kanamoto 《Nutrients》2021,13(6)
The purpose of this study was to examine how gold kiwifruit pericarp (pericarp is defined as the skin of the fruit) consumption and the timing thereof affect the postprandial blood glucose profile. The study was conducted on twelve healthy volunteers (six men and six women). According to our results, the simultaneous intake of gold kiwifruit with bread and the prior intake of gold kiwifruit evidently suppressed the postprandial blood glucose elevation compared with exclusive bread intake. There was no significant difference in postprandial blood glucose changes between the ingestion of gold kiwifruit pericarp and pulp and that of gold kiwifruit pulp only. The highest postprandial blood glucose elevation was suppressed by 27.6% and the area under the blood glucose elevation curve by 29.3%, even with the exclusive ingestion of gold kiwifruit pulp. We predicted that the ingestion of both the pericarp and pulp of gold kiwifruit would reduce the postprandial blood glucose elevation to a greater extent than that of gold kiwifruit pulp only; however, there was no significant difference between the two. These results indicate that gold kiwifruit consumption significantly suppresses the postprandial blood glucose elevation regardless of pericarp presence or absence and the timing of ingestion. 相似文献
999.
Tanvir S Sian Ushnah S. U. Din Colleen S. Deane Ken Smith Amanda Gates Jonathan N. Lund John P. Williams Ricardo Rueda Suzette L. Pereira Bethan E. Phillips Philip J. Atherton 《Nutrients》2021,13(5)
Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450–500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake. 相似文献
1000.
目的探讨聚合酶链反应检验法在阴道炎患者阴道细菌检查中的应用价值。方法选取2019年6月~2020年6月于我院行细菌检查的58例阴道炎患者为研究对象,所有患者均采用阴道分泌物细菌培养、聚合酶链式反应(PCR)检验,比较两种检验方法阳性检出率。结果PCR检验阳性检出率(89.66%)高于细菌培养法(70.69%),差异有统计学意义(P<0.05)。结论PCR检验法应于阴道炎患者阴道细菌检查中,阳性检出率高,可为阴道炎的诊断及治疗提供较准确的科学依据,具有较高的临床应用价值。 相似文献