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41.
Martha?I?Murcia-Aranguren Jorge?E?Gómez-MarinEmail author Fernando?S?Alvarado José?G?Bustillo Ellen?de Mendivelson Bertha?Gómez Clara?I?León William?A?Triana Erwing?A?Vargas Edgar?Rodríguez 《BMC infectious diseases》2001,1(1):21
Background
The prevalence of infections by Mycobacterium tuberculosis and non-tuberculous Mycobacterium species in the HIV-infected patient population in Colombia was uncertain despite some pilot studies. We determined the frequency of isolation of Mycobacterium tuberculosis and of non-tuberculous Mycobacterium species in diverse body fluids of HIV-infected patients in Bogota, Colombia. 相似文献42.
43.
原纤维蛋白-1 mRNA和蛋白在子宫肌瘤组织中的表达 总被引:1,自引:0,他引:1
目的:探讨原纤维蛋白-1(fibrillin-1,FBN-1)mRNA和蛋白在子宫肌瘤组织中的表达及其与月经周期的关系。方法:50份子宫肌瘤及同源正常子宫平滑肌组织标本在术中被采集。根据月经周期及子宫内膜组织病理学检查分为增生期、分泌期及萎缩期。采用实时荧光定量PCR、Western blot分析及免疫组织化学方法检测FBN-1 mRNA和蛋白的表达。结果:免疫组织化学染色显示FBN-1在子宫肌瘤及正常子宫平滑肌组织的细胞外基质中均有较丰富的表达。FBN-1 mRNA和蛋白在增生期和分泌期中的子宫肌瘤组织中的表达均明显高于同源正常子宫平滑肌组织(P<0.01,P<0.05;P<0.01,P<0.05),而在绝经期中的子宫平滑肌瘤及正常子宫平滑肌组织的表达无明显差异。结论:FBN-1可能与子宫肌瘤的发生机制有关,并可能受激素调节的影响。 相似文献
44.
45.
Blanca E. Alcántar-Díaz Belinda C. Gómez-Meda Guillermo M. Zúñiga-González Ana L. Zamora-Perez Jaime González-Cuevas Bertha A. Álvarez-Rodríguez María Guadalupe Sánchez-Parada Jesús J. García-Bañuelos Juan Armendáriz-Borunda 《Food and chemical toxicology》2012
Pirfenidone is a non-steroidal antifibrotic compound that has been proposed in clinical protocols and experimental studies as a pharmacological treatment for fibroproliferative diseases. The objective of this study was to determine the genotoxicity or cytotoxicity of three doses of pirfenidone using the micronuclei test in peripheral blood erythrocytes of rodent models. Pirfenidone was administered orally to Balb-C mice for 3 days, and also was administered topically to hairless Sprague Dawley rats during the final stage of gestation. Mice were sampled every 24 h over the course of 6 days; pregnant rats were sampled every 24 h during the last 6 days of gestation, and pups were sampled at birth. Blood smears were analyzed and the frequencies of micronucleated erythrocytes (MNEs), micronucleated polychromatic erythrocytes (MNPCEs), and the proportion of polychromatic erythrocytes (PCEs), were recorded in samples from mice, pregnant rats and rat neonates. Increases in MN frequencies (p < 0.03) were noted only in the positive control groups. No genotoxic effects or decreased PCE values were observed neither in newborn rats transplacentally exposed to pirfenidone, or in two adult rodent models when pirfenidone was administered orally or topically. 相似文献
46.
Tebo Maseko Frank Rowland Dunshea Kate Howell Hyun-Jung Cho Leni Rose Rivera John Barton Furness Ken Ng 《Nutrients》2014,6(6):2478-2492
Dietary effects of organic Se supplementation in the form of Se-enriched Agaricus bisporus mushroom on ileal mucosal permeability and antioxidant selenoenzymes status in heat induced oxidative stress in rats were evaluated. Acute heat stress (40 °C, 21% relative humidity, 90 min exposure) increased ileum baseline short circuit current (Isc; 2.40-fold) and epithelial conductance (Ge; 2.74-fold). Dietary supplementation with Se-enriched A. bisporus (1 µg Se/g feed) reduced (p < 0.05) ileum Isc and Ge during heat stress to 1.74 and 1.91 fold, respectively, indicating protection from heat stress-induced mucosal permeability increase. The expression of ileum glutathione peroxidase (GPx-) 1 and 2 mRNAs were up-regulated (p < 0.05) by 1.90 and 1.87-fold, respectively, for non-heat stress rats on the Se-enriched diet relative to the control. The interplay between heat stress and dietary Se is complex. For rats on the control diet, heat stress alone increased ileum expression of GPx-1 (2.33-fold) and GPx-2 (2.23-fold) relative to thermoneutral conditions. For rats on the Se-enriched diet, heat stress increased (p < 0.05) GPx-1 expression only. Rats on Se-enriched + α-tocopherol diet exhibited increased expression of both genes (p < 0.05). Thus, dietary Se-enriched A. bisporus protected against increase in ileum permeability and up-regulated GPx-1 and GPx-2 expression, selenoenzymes relevant to mitigating oxidative stress. 相似文献
47.
Chronic kidney disease (CKD) is a public health concern that affects approximately 10% of the global population. CKD is associated with poor outcomes due to high frequencies of comorbidities such as heart failure and cardiovascular disease. Uremic toxins are compounds that are usually filtered and excreted by the kidneys. With the decline of renal function, uremic toxins are accumulated in the systemic circulation and tissues, which hastens the progression of CKD and concomitant comorbidities. Gut microbial dysbiosis, defined as an imbalance of the gut microbial community, is one of the comorbidities of CKD. Meanwhile, gut dysbiosis plays a pathological role in accelerating CKD progression through the production of further uremic toxins in the gastrointestinal tracts. Therefore, the gut-kidney axis has been attracting attention in recent years as a potential therapeutic target for stopping CKD. Trimethylamine N-oxide (TMAO) generated by gut microbiota is linked to the progression of cardiovascular disease and CKD. Also, advanced glycation endproducts (AGEs) not only promote CKD but also cause gut dysbiosis with disruption of the intestinal barrier. This review summarizes the underlying mechanism for how gut microbial dysbiosis promotes kidney injury and highlights the wide-ranging interventions to counter dysbiosis for CKD patients from the view of uremic toxins such as TMAO and AGEs. 相似文献
48.
Verrico CD Lynch L Fahey MA Fryer AK Miller GM Madras BK 《Journal of psychopharmacology (Oxford, England)》2008,22(2):187-202
Human MDMA (R,S-3,4-methylenedioxymethamphetamine) users display selective cognitive deficits after acute MDMA exposure, frequently attributed to serotonin deficits. We postulated that MDMA will compromise executive function in primates and that an inhibitor of the serotonin transporter (SERT) and the norepinephrine transporter (NET) but not the dopamine (DAT) transporter, will prevent impairment. The potencies of DAT/NET, NET and SERT inhibitors to block transport of [(3)H]MDMA and [(3)H]monoamines were compared in vitro. Subsequently, cynomolgus monkeys (Macaca fasicularis) were trained to stable performance in a reversal learning task. Effects of once-weekly oral or i.m. dose of MDMA (1.5 mg/kg, n = 4) on performance were monitored, alone or after pretreatment with inhibitors of the SERT, DAT or NET (prior to i.m. MDMA). 1) Drug potencies for blocking [(3)H]MDMA or [(3)H]monoamine transport were not consistent; 2) Oral MDMA increased error rates in a cognitive task for up to three days following exposure, whereas intramuscular MDMA prevented subjects from performing the cognitive task on the day of administration, but not on subsequent days; 3) The SERT inhibitor citalopram and the NET inhibitor desipramine, but not the DAT/NET inhibitor methylphenidate, reversed the effects of MDMA on task performance and mandibular movements induced by i.m. MDMA and 4) MDMA altered sleep latency. Oral MDMA impairs executive function in monkeys for several days, a finding of potential relevance to MDMA consumption by humans. Reversal of impaired executive function by a NET inhibitor implicates the NET and norepinephrine in MDMA-induced cognitive impairment and may be relevant to therapeutic strategies. 相似文献
49.
Morales-Medina JC Mejorada A Romero-Curiel A Aguilar-Alonso P León-Chávez BA Gamboa C Quirion R Flores G 《Neuropharmacology》2008,55(8):1313-1320
Nitric oxide (NO) is associated with dopamine (DA) release. Previously, we demonstrated that rats treated with a non-selective nitric oxide synthase inhibitor, N-omega-nitro-l-arginine (l-NNA) at postnatal days 4-6 (PD4-6) show increased locomotion and disrupt neuronal cytoarchitecture after puberty (PD60). Here, we investigate whether the modulation of NO production in rats at PD4-6 causes long term changes of NO system, its impact on DA innervation, and schizophrenia-like behaviors. NO levels were measured in seven brain areas at PD35, PD60, PD90, and PD120. Autoradiographic studies explored the effect of l-NNA on the expression of D1 and D2 receptors in the caudate-putamen (CPu) and nucleus accumbens (NAcc) at PD60. Locomotor activity was assessed at PD60 using the non-selective DA agonists, amphetamine and apomorphine, and the selective DA receptor agonist [D2, quinpirole; D3, 7-hydroxy-N,N-di-n-propylaminotetralin ((±)-7-OH-DPAT)]. l-NNA treatment produced decreases in NO levels in the frontal cortex, striatum, brainstem and cerebellum, while in the occipital cortex changes were observed at PD120. Hippocampus and temporoparietal cortex showed differential levels of NO. Receptor autoradiography revealed increases in D1 receptor levels in the NAcc (shell), while decreases in D2 receptor binding were observed in the CPu and NAcc (core). Amphetamine and quinpirole treatments resulted in increases in locomotion. In contrast, treatment with 7-OH-DPAT produced hypolocomotion at low doses, while increased locomotion was seen at the highest dose. These results show that modulation of NO levels early postnatally (PD4-6) produces long term alteration in NO levels, with possible consequences on DA transmission, and related behaviors relevant to schizophrenia. 相似文献
50.
Bertha Nhlema Simwaka George Bello Hastings Banda Rhehab Chimzizi Bertel SB Squire Sally J Theobald 《International journal for equity in health》2007,6(1):24