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991.
David Fabregat-Safont Marie Mardal Juan V.Sancho Félix Hernández Kristian Linnet María Ibánez 《Journal of Pharmaceutical Analysis》2020,10(2):147-156
Synthetic cathinones are new psychoactive substances that represent a health risk worldwide.For most of the 130 reported compounds,information about toxicology and/or metabolism is not available,which hampers their detection(and subsequent medical treatment)in intoxication cases.The principles of forensic analytical chemistry and the use of powerful analytical techniques are indispensable for stab-lishing the most appropriate biomarkers for these substances.Human metabolic fate of synthetic cathinones can be assessed by the analysis of urine and blood obtained from authentic consumers;however,this type of samples is limited and difficult to access.In this work,the metabolic behaviour of three synthetic cathinones(4-CEC,4-CPrC and 5-PPDi)and one amphetamine(3-FEA)has been evalu-ated by incubation with pooled human hepatocytes and metabolite identification has been performed by high-resolution mass spectrometry.This in vitro approach has previously shown its feasibility for obtaining excretory human metabolites.4-CEC and 3-FEA were not metabolised,and for 4-CPrC only two minor metabolites were obtained.On the contrary,for the recently reported 5-PPDi,twelve phase I metabolites were elucidated.Up to our knowledge,this is the first metabolic study of an indanyl-cathinone.Data reported in this paper will allow the detection of these synthetic stimulants in intoxi-cation cases,and will facilitate future research on the metabolic behaviour of other indanyl-based cathinones. 相似文献
992.
目的 探讨大黄素-8-O-β-D-吡喃葡萄糖苷对牙龈卟啉单胞菌(P. gingivalis)唾液酸酶活性及其毒力基因表达的影响。方法 使用不同质量浓度的大黄素-8-O-β-D-吡喃葡萄糖苷(0.2、0.5、2、5、10 mg/mL)处理P. gingivalis W83(实验组),用未加药物的P. gingivalis W83作对照(对照组),采用荧光法检测大黄素-8-O-β-D-吡喃葡萄糖苷对P. gingivalis唾液酸酶活性的作用。5 mg/mL大黄素-8-O-β-D-吡喃葡萄糖苷作用于P. gingivalis W83,Real-time PCR法检测毒力基因fimA、fimR、fimS、kgp、rgpA和rgpB的表达情况。结果 大黄素-8-O-β-D-吡喃葡萄糖苷对P. gingivalis唾液酸酶活性产生了抑制作用,当其质量浓度为0.2、0.5、2、5、10 mg/mL时,对唾液酸酶活性的抑制率分别为11.4%、32.23%、40.21%、73.54%、84.31%。与对照组比较,实验组(5 mg/mL大黄素-8-O-β-D-吡喃葡萄糖苷处理)的fimA、fimR、fimS、kgp、rgpA和rgpB基因表达均下降,差异均有统计学意义(均P < 0.05)。结论 大黄素-8-O-β-D-吡喃葡萄糖苷可有效抑制P. gingivalis唾液酸酶活性,其抑制作用会降低细菌毒力基因表达,有望成为预防及治疗牙周炎的新型药物。 相似文献
993.
随着生活水平及治疗技术的提高,种植修复成为越来越多患者的选择。良好的牙槽嵴和牙龈解剖形态的保存或重建是修复体获得满意美学效果和长期稳定性的先决条件。下前牙是牙周炎的好发牙位,下前牙松动脱落伴随下颌骨的吸收势必会造成软硬组织缺陷。文章完整展示了1例罹患重度牙周病变的下前牙即刻种植、同期引导骨再生结合帐篷式植骨术创造良好硬组织三维条件,获得最终较好种植修复效果的具体实施步骤,积累了针对此类问题的临床经验。 相似文献
994.
目的了解河南省省直离退休干部代谢综合征(MS)相关疾病的状况。方法分析2011年河南省某省级医院对1 411名离退休干部的健康体检结果,包括体重、身高、血压,检测甘油三酯、胆固醇、空腹血糖、高密度脂蛋白、低密度脂蛋白等,对MS患病状况进行描述分析。结果离退休干部MS的总患病率为25.7%,超重组MS患病率(40.0%)明显高于非超重组3.6%,MS患病率在性别组、年龄组间都无统计学差异。结论河南省直离退休干部MS患病较严重,应增强健康意识,倡导健康的生活方式。 相似文献
995.
de Oliveira AC Andreotti S Farias Tda S Torres-Leal FL de Proença AR Campaña AB de Souza AH Sertié RA Carpinelli AR Cipolla-Neto J Lima FB 《Endocrinology》2012,153(5):2178-2188
Diabetes mellitus is a product of low insulin sensibility and pancreatic β-cell insufficiency. Rats with streptozotocin-induced diabetes during the neonatal period by the fifth day of age develop the classic diabetic picture of hyperglycemia, hypoinsulinemia, polyuria, and polydipsia aggravated by insulin resistance in adulthood. In this study, we investigated whether the effect of long-term treatment with melatonin can improve insulin resistance and other metabolic disorders in these animals. At the fourth week of age, diabetic animals started an 8-wk treatment with melatonin (1 mg/kg body weight) in the drinking water at night. Animals were then killing, and the sc, epididymal (EP), and retroperitoneal (RP) fat pads were excised, weighed, and processed for adipocyte isolation for morphometric analysis as well as for measuring glucose uptake, oxidation, and incorporation of glucose into lipids. Blood samples were collected for biochemical assays. Melatonin treatment reduced hyperglycemia, polydipsia, and polyphagia as well as improved insulin resistance as demonstrated by constant glucose disappearance rate and homeostasis model of assessment-insulin resistance. However, melatonin treatment was unable to recover body weight deficiency, fat mass, and adipocyte size of diabetic animals. Adiponectin and fructosamine levels were completely recovered by melatonin, whereas neither plasma insulin level nor insulin secretion capacity was improved in diabetic animals. Furthermore, melatonin caused a marked delay in the sexual development, leaving genital structures smaller than those of nontreated diabetic animals. Melatonin treatment improved the responsiveness of adipocytes to insulin in diabetic animals measured by tests of glucose uptake (sc, EP, and RP), glucose oxidation, and incorporation of glucose into lipids (EP and RP), an effect that seems partially related to an increased expression of insulin receptor substrate 1, acetyl-coenzyme A carboxylase and fatty acid synthase. In conclusion, melatonin treatment was capable of ameliorating the metabolic abnormalities in this particular diabetes model, including insulin resistance and promoting a better long-term glycemic control. 相似文献
996.
Román-García P Carrillo-López N Naves-Díaz M Rodríguez I Ortiz A Cannata-Andía JB 《Endocrinology》2012,153(4):1627-1637
Phosphate load accelerates the progression of secondary hyperparathyroidism (sHPT). In advanced stages of sHPT, there is a marked hyperplasia and resistance to classical regulatory endocrine factors such as calcium, calcitriol, or fibroblast growth factor 23 (FGF23), which suppresses PTH secretion by an ERK-dependent mechanism. Nephrectomized rats were fed with a high- or normal-phosphorus diet for different periods of time to induce sHPT. Biochemical parameters, parathyroid gland microarrays, quantitative real-time PCR, and immunohistochemistry (ERK/phospho-ERK) were performed. To test the role of dual-specificity phosphatases (Dusp) on parathyroid gland regulation, normal parathyroid glands were cultured with FGF23 and Dusp. Uremic rats fed with a high-phosphorus diet showed more severe sHPT, higher serum FGF23 levels and mortality, and decreased parathyroid Klotho gene expression. In all stages of sHPT, parathyroid microarrays displayed a widespread gene expression down-regulation; only a few genes were overexpressed, among them, Dusp5 and -6. In very severe sHPT, a significant reduction in phospho-ERK (the target of Dusp) and a significant increase of Dusp5 and -6 gene expression were observed. In ex vivo experiments with parathyroid glands, Dusp partially blocked the effect of FGF23 on PTH secretion, suggesting that Dusp might play a role in parathyroid regulation. The overexpression of Dusp and the inactivation of ERK found in the in vivo studies together with the ex vivo results might be indicative of the defense mechanism triggered to counteract hyperplasia, a mechanism that can also contribute to the resistance to the effect of FGF23 on parathyroid gland observed in advanced forms of chronic kidney disease. 相似文献
997.
998.
P Labarga P Barreiro A da Silva JM Guardiola R Rubio K Aguirrebengoa P Miralles J Portu MJ Téllez L Morano A Castro JA Pineda A Terrón J Hernández-Quero A Mariño MJ Ríos S Echeverría V Asensi E Vispo V Soriano;on behalf of PERICO Study Group 《The Journal of infectious diseases》2012,206(6):961-968
Background.?Ribavirin (RBV) exposure seems to be critical to maximize treatment response in human immunodeficiency virus (HIV)-positive patients with chronic hepatitis C virus (HCV) infection. Methods.?HIV/HCV-coinfected individuals naive to interferon were prospectively randomized to receive peginterferon-α-2a (180?μg/d) plus either RBV standard dosing (1000 or 1200?mg/d if <75 or ≥75?kg, respectively) or RBV induction (2000?mg/d) along with subcutaneous erythropoietin β (450?IU/kg/wk), both during the first 4 weeks, followed by standard RBV dosing until completion of therapy. Early stopping rules at weeks 12 and 24 were applied in patients with suboptimal virological response. Results.?A total of 357 patients received ≥1 dose of the study medication. No differences in main baseline characteristics were found when comparing treatment arms. Sustained virological response (SVR) was attained by 160 (45%) patients, with no significant differences between RBV induction and standard treatment arms (SVR in 72 of 169 patients [43%] vs 88 of 188 [47%], respectively). At week 4, undetectable HCV RNA (29% vs 25%) and mean RBV trough concentration (2.48 vs 2.14?μg/mL) were comparable in both arms, whereas mean hemoglobin decay was less pronounced in the RBV induction plus erythropoietin arm than in the RBV standard dosing arm (-1.7 vs -2.3?mg/dL; P?.005). Treatment discontinuation occurred in 91 (25%) patients owing to nonresponse and in 29 (8%) owing to adverse events. HCV relapse occurred in 34 patients (10%). Univariate and multivariate analyses identified HCV genotype 2 or 3 (odds ratio [OR], 10.3; 95% confidence interval [CI], 2.08-50.2; P?=?.004), IL28B CC variants (OR, 2.92; 95% CI, 1.33-6.41; P?=?.007), nonadvanced liver fibrosis (OR, 2.27; 95% CI, 1.06-5.01; P?=?.03), and rapid virological response (OR, 40.3; 95% CI, 5.1-314.1; P?.001) as predictors of SVR. Conclusions.?A 4-week course of induction therapy with high RBV dosing along with erythropoietin does not improve SVR rates in HIV/HCV-coinfected patients. Preemptive erythropoietin might blunt the benefit of RBV overdosing by enhancing erythrocyte uptake of plasma RBV. 相似文献
999.
We present a case of 44 year-old female who was admitted to the hospital due to performed radio frequency ablation because of VF during WPW syndrome, which was complicated by dissection of left main. The dissection was treated with success by primary percutaneous coronary intervention with two metal stents. 相似文献
1000.
NF Gnädig S Beaucourt G Campagnola AV Bordería M Sanz-Ramos P Gong H Blanc OB Peersen M Vignuzzi 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(34):E2294-E2303
Based on structural data of the RNA-dependent RNA polymerase, rational targeting of key residues, and screens for Coxsackievirus B3 fidelity variants, we isolated nine polymerase variants with mutator phenotypes, which allowed us to probe the effects of lowering fidelity on virus replication, mutability, and in vivo fitness. These mutator strains generate higher mutation frequencies than WT virus and are more sensitive to mutagenic treatments, and their purified polymerases present lower-fidelity profiles in an in vitro incorporation assay. Whereas these strains replicate with WT-like kinetics in tissue culture, in vivo infections reveal a strong correlation between mutation frequency and fitness. Variants with the highest mutation frequencies are less fit in vivo and fail to productively infect important target organs, such as the heart or pancreas. Furthermore, whereas WT virus is readily detectable in target organs 30 d after infection, some variants fail to successfully establish persistent infections. Our results show that, although mutator strains are sufficiently fit when grown in large population size, their fitness is greatly impacted when subjected to severe bottlenecking, which would occur during in vivo infection. The data indicate that, although RNA viruses have extreme mutation frequencies to maximize adaptability, nature has fine-tuned replication fidelity. Our work forges ground in showing that the mutability of RNA viruses does have an upper limit, where larger than natural genetic diversity is deleterious to virus survival. 相似文献