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排序方式: 共有10000条查询结果,搜索用时 218 毫秒
901.
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Wei Jia Duan Xiao Zhong Wang An Lin Ma Jia Shang Yue Min Nan Zhi Liang Gao Hong Tang Qing Chun Fu Qing Xie Qing Mao Jun Qi Niu Tao Han Jun Li Ying Han Jian Biao Cao Yuan Yuan Kong Xiao Yan Shi Fu Dong Lv Tai Ling Wang Hong Ma Hong You Xiao Juan Ou Ji Dong Jia 《Journal of digestive diseases》2020,21(9):519-525
904.
Yang Zhu BM Xiaohong Liu MM Xin Wei MM Baisong Wang PhD Jiuchang Zhong MD Yi Fu MD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(9):652-657
To study the relationship between nocturnal blood pressure (BP) variation and spontaneous intracerebral hemorrhage (ICH) among Chinese hypertensive patients and its clinical significance, the authors retrospectively screened 371 patients with primary hypertension (189 patients with ICH, 182 patients without ICH) in Shanghai and analyzed their demographics, clinical information, nocturnal blood pressure variability and medication. Compared with the control group, the levels of blood glucose, triglycerides, and creatinine were significantly increased in the ICH group, along with a marked reduction in nocturnal BP drop (P<.05). Multivariate logistic regression indicated that blood glucose, creatinine, and nocturnal mean arterial pressure were risk factors for ICH, and the magnitude of nocturnal BP drop was negatively related to the risk for ICH. There was no significant difference in the prevalence of reverse dippers between the large hematoma volume group and the small hematoma volume group (χ2=2.529, P=.112), nor among the patients taking angiotensin‐converting enzyme inhibitors, angiotensin receptor blockers, or calcium channel blockers (χ2=1.981, P=.371). Reverse dipping is associated with the risk for ICH, suggesting that appropriate antihypertensive drug and chronotherapy might be effective to normalize the rhythm of abnormal circadian variation in hypertensive patients. 相似文献
905.
ABSTRACT The early-life gut microbiota is associated with potential development of diseases in adulthood. The sterile womb paradigm has been challenged by recent reports that revealed the presence of the meconium, amniotic fluid, and placenta microbiome. This study aimed to explore the maternal origin of the microbiota of neonate meconium by using the PacBio single-molecule real-time circular consensus sequencing technology. Such technology could produce high fidelity reads of full-length 16S rRNA genes, improving the sensitivity and specificity of taxonomic profiling. It also reduced the risk of false positives. This study analyzed the full-length 16S rRNA-based microbiota of maternal samples (amniotic fluid, feces, vaginal fluid, saliva) and first-pass meconium of 39 maternal-neonate pairs. Alpha- and beta-diversity analyses revealed sample type-specific microbiota features. Most sample types were dominated by sequences representing different genera (Lactobacillus and Curvibacter in the amniotic fluid and vaginal fluid microbiota; Bacillus and Escherichia/Shigella in the meconium microbiota; Bacteroides and Faecalibacterium in the maternal fecal microbiota; Streptococcus and Prevotella in the maternal saliva microbiota). Moreover, specific operational taxonomic units (OTUs) were identified in all sample types. Dyad analysis revealed common OTUs between the meconium microbiota and microbiota of multiple maternal samples. The meconium microbiota shared more features with the amniotic fluid microbiota than the maternal fecal and vaginal microbiota. Our results strongly suggested that the meconium microbiota was seeded from multiple maternal body sites, and the amniotic fluid microbiota contributed most to the seeding of the meconium microbiota among the investigated maternal body sites. 相似文献
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907.
Xiaosang Chen Shuanggen Xue Jun Xu Ming Zhong Xiaochuan Liu Guangyi Lin Yaxing Shen Lijie Tan 《Journal of thoracic disease》2020,12(11):6505
BackgroundTranscervical esophagectomy is a less invasive procedure performed within mediastinum. However, the mediastinum offers limited surgical space and the surgery via this route differs from conventional minimally invasive esophagectomy. Therefore, the physiological study of this surgical approach on an animal model would be necessary before the procedure gained more popularity.MethodsWe conducted transcervical minimally invasive esophagectomy on animal model (swine) under CO2 pneumomediastinum. The hemodynamic parameters were monitored using float catheter cannulated via right jugular vein. At different anatomical level (the upper, middle, and lower thoracic part of the animal esophagus), increased artificial pneumomediastinal pressures (0, 4, 8, 12, and 16 mmHg) were consecutively allocated to record the intra-operative changes of blood pressure, cardiac output (CO), central venous pressure (CVP), pulmonary artery pressure (PAP) and extravascular lung water (EVLW). Meanwhile, the surgical field under different pneumomediastinum pressure was recorded and balanced with animals’ hemodynamic changes to determine the optimal pressure for transcervical minimally invasive esophagectomy.ResultsThe animal procedures were accomplished without conversions. During the upper thoracic stage, increased CO2 pressures did not lead to significant changes in hemodynamic parameters including the blood pressure, CO, CVP, PAP or the level of EVLW. During the middle thoracic stage, pneumomediastinum under 4–12 mmHg did not lead to significant changes in hemodynamic parameters. However, pneumomediastinum at 16 mmHg resulted in lower CO (P=0.038) when compared to 0–12 mmHg. During lower thoracic stage, as the pneumomediastinum pressures increased from 0 to 16 mmHg, significant decrease in CO (P=0.022), and increase in CVP (P=0.036) was recorded. In compared to 4 mmHg pneumomediastinum, the surgical field under 8–16 mmHg artificial CO2 pneumomediastinum was suitable for mediastinal manipulation.ConclusionsDuring transcervical minimally invasive esophagectomy on animal model, the mobilization of swine thoracic esophagus with optimal pneumomediastinum pressure 8–12 mmHg is safe and effective based on hemodynamic analysis. 相似文献
908.
Hai-Bo Tang Zhuan-Ling Lu Yi-Zhi Zhong Xiao-Xia He Tao-Zhen Zhong Yan Pan Xian-Kai Wei Yang Luo Su-Huan Liao Nobuyuki Minamoto Ting Rong Luo 《Virus genes》2014,49(3):417-427
In this study, a street rabies virus isolate, GXHXN, was obtained from the brain of one rabid cattle in Guangxi province of southern China. To characterize the biological properties of GXHXN, we first evaluated its pathogenicity using 4-week-old adult mice. GXHXN was highly pathogenic with a short incubation period and course of disease. Its LD50 of 10?6.86/mL is significantly higher than the LD50 of 10?5.19/mL of GXN119, a dog-derived rabies virus isolate. It also displayed a higher neurotropism index than the rRC-HL strain. However, the relative neurotropism index of GXHXN was slightly lower than that of GXN119. Analyzing antigenicity using anti-N and anti-G monoclonal antibodies (MAbs), all tested anti-N MAbs reacted similarly to GXHXN, CVS, and rRC-HL, but the reaction of anti-N MAbs to GXHXN was slightly different from GXN119. Moreover, 2/11 tested anti-G mAbs showed weaker reactivity to GXHXN than rRC-HL, whereas 4/11 showed stronger reactivity to GXHXN than CVS and GXN119, indicating that the structures of G might differ. In order to understand its genetic variation and evolution, the complete GXHXN genome sequence was determined and compared with the known 12 isolates from other mammals. A total of 42 nucleotide substitutions were found in the full-length genome, including 15 non-synonymous mutations. The G gene accounts for the highest nucleotide substitution rate of 0.70 % in ORF and an amino acid substitution rate of 0.95 %. Phylogenetic trees based on the complete genome sequence as well as the N and G gene sequences from 37 known rabies isolates from various mammals demonstrated that the GXHXN is closely related to the BJ2011E isolate from a horse in Beijing, the WH11 isolate from a donkey in Hubei, and isolates from dogs in the Fujian and Zhejiang provinces. These findings will be helpful in exploring the molecular mechanisms underlying interspecies transmission and the genetic variation of the rabies virus in different mammal species. 相似文献
909.
目的:探讨建立人胰腺癌PANC-1裸鼠移植瘤模型的最佳实验方法,并应用该模型进行载基因纳米微粒体内效应的研究。方法:将不同数量PANC-1细胞悬液接种于BALB/c (nu/nu)小鼠右侧背部皮下,当肿瘤体积达100 mm3时尾静脉注射siRNACY5.5纳米复合物进行活体荧光成像。此外,于尾静脉注射负载siRNAKras纳米复合物,蛋白印迹及免疫组织化学染色法观察肿瘤组织Kras蛋白表达水平。结果:1×107 cells/300 μL 接种成瘤率达100%,成瘤时间<2周。荧光呈像及组织学检查显示载siRNA纳米微粒可靶向聚集在肿瘤组织发挥体内基因沉默效应。结论:本研究报道的人胰腺癌裸鼠移植瘤模型建立方法成瘤率达100%,成瘤时间短,是研究药物示踪和观察疗效的理想模型。 相似文献
910.
Innate immune receptor NOD2 promotes vascular inflammation and formation of lipid‐rich necrotic cores in hypercholesterolemic mice
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Maria E. Johansson Xiao‐Ying Zhang Kristina Edfeldt Anna M. Lundberg Malin C. Levin Jan Borén Wei Li Xi‐Ming Yuan Lasse Folkersen Per Eriksson Ulf Hedin Hann Low Dmitri Sviridov Francisco J. Rios Göran K. Hansson Zhong‐Qun Yan 《European journal of immunology》2014,44(10):3081-3092
Atherosclerosis is an inflammatory disease associated with the activation of innate immune TLRs and nucleotide‐binding oligomerization domain‐containing protein (NOD)‐like receptor pathways. However, the function of most innate immune receptors in atherosclerosis remains unclear. Here, we show that NOD2 is a crucial innate immune receptor influencing vascular inflammation and atherosclerosis severity. 10‐week stimulation with muramyl dipeptide (MDP), the NOD2 cognate ligand, aggravated atherosclerosis, as indicated by the augmented lesion burden, increased vascular inflammation and enlarged lipid‐rich necrotic cores in Ldlr?/? mice. Myeloid‐specific ablation of NOD2, but not its downstream kinase, receptor‐interacting serine/threonine‐protein kinase 2, restrained the expansion of the lipid‐rich necrotic core in Ldlr?/? chimeric mice. In vitro stimulation of macrophages with MDP enhanced the uptake of oxidized low‐density lipoprotein and impaired cholesterol efflux in concordance with upregulation of scavenger receptor A1/2 and downregulation of ATP‐binding cassette transporter A1. Ex vivo stimulation of human carotid plaques with MDP led to increased activation of inflammatory signaling pathways p38 MAPK and NF‐κB‐mediated release of proinflammatory cytokines. Altogether, this study suggests that NOD2 contributes to the expansion of the lipid‐rich necrotic core and promotes vascular inflammation in atherosclerosis. 相似文献