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1.
目的 探讨骨质疏松症患者血清硫化氢(H2S)的变化及临床意义。方法 收集骨质疏松症患者128例作为骨质疏松组,另选取腰背部疼痛但排除骨质疏松的患者110例作为对照组。采用双能X线骨密度仪检测腰椎(L1~4)和双侧股骨颈骨密度,亚洲人骨质疏松自我筛查工具(OSTA)筛查骨质疏松风险。采集空腹静脉血5 mL,检测血清H2S、碱性磷酸酶(ALP)、骨特异性碱性磷酸酶(BALP)、血磷、血钙、血清骨钙素、甲状旁腺素(iPTH)、Ⅰ型原胶原N-端前肽(P1NP)、Ⅰ型胶原C-末端肽交联(P1CP)、Ⅰ型胶原羧基端肽β特殊序列(β-CTX)等骨代谢标志物水平。Pearson相关分析骨质疏松症患者血清H2S与骨代谢标志物的相关性。结果 与对照组相比,骨质疏松组患者腰椎骨密度、股骨颈骨密度、OSTA指数和血清H2S浓度下降,血清ALP、BALP、骨钙素、P1NP、P1CP、iPTH水平下降,β-CTX水平升高(P<0.05)。骨质疏松症患者血清H2S与ALP、BALP、血清骨钙素、P1NP、P1CP、iPTH呈正相关,与β-CTX呈负相关(均P<0.05)。结论 骨质疏松症患者血清H2S水平出现明显下降,检测H2S有助于评估患者骨代谢水平。  相似文献   
2.
目的利用多体素氢质子磁共振波谱成像(hydrogen proton magnetic resonance spectroscopy,1H-MRS)探讨慢性高原病(chronic mountain sickness,CMS)长期缺氧状态下脑部代谢物的特点,并比较各代谢物与血液指标之间的相关性。材料与方法前瞻性纳入青海大学附属医院经临床确诊为CMS的17例男性患者作为实验组,年龄(53.29±9.03)岁,居住海拔(3989.12±937.45)m,血红蛋白(hemoglobin,HGB)(224.35±11.81)g/mL,并招募与实验组年龄及居住海拔相匹配的18名健康男性志愿者作为对照组,年龄(48.61±8.76)岁,居住海拔(3674.94±634.27)m,HGB(156.67±9.46)g/mL。采用Siemens Prisma 3.0 T MR扫描仪20通道头颅线圈对所有受试者行常规头颅MRI及多体素;H-MRS检查,通过Syngo.via后处理软件获得;H-MRS图,ROI选取双侧额叶及海马区,并获得相应脑区N-乙酰天门冬氨酸/肌酸(NAA/Cr)、胆碱/肌酸CHo/Cr、乙酰天门冬氨酸/胆碱(NAA/CHo)、乳酸/肌酸(Lac/Cr)的比值。结合独立样本t检验及非参数曼-惠特尼U检验以比较两组间代谢物相对浓度差异,然后将CMS组双侧额叶及海马区各代谢物比值与血液生化指标作相关性分析。结果(1)两组受试者年龄、长期居住海拔差异均无统计学意义(P>0.05),而与对照组相比,CMS组HGB、红细胞计数(red blood cell count,RBC)、血细胞比容(hematocrit,HCT)增高,血小板(blood platelet,简称PLT)减低,差异均有统计学意义(P<0.01);(2)与对照组相比,CMS组双侧额叶及海马区NAA/Cr及NAA/CHo均减低(P<0.05),Lac/Cr增高(P<0.05),差异均具有统计学意义;(3)与对照组相比,CMS组双侧额叶及双侧海马区CHo/Cr均增高(P>0.05),差异无统计学意义;(4)CMS组右侧额叶及左侧海马CHo/Cr与RBC明显正相关,左侧额叶CHo/Cr与HCT低度正相关,右侧额叶及左侧海马Lac/Cr与HCT低度正相关。结论CMS长期缺氧状态下脑组织局部代谢物改变,神经元受损,无氧代谢增加,且这些代谢物的改变与血液指标呈一定的相关性,可为临床后续进一步预防或干预CMS患者脑损害提供影像学证据及监测指标。  相似文献   
3.
《中国现代医生》2019,57(35):41-43+47
目的探讨依达拉奉联合硫酸氢氯吡格雷治疗急性脑梗死的临床效果及对同型半胱氨酸水平的影响。方法采用便利抽样法选取2018年6月~2019年6月我院收治的60例急性脑梗死患者,按照随机数字表法分为观察组和对照组,每组30例。两组患者均给予常规治疗,对照组在常规治疗基础上采用依达拉奉联合拜阿司匹林进行治疗,观察组在常规治疗基础上采用依达拉奉联合硫酸氢氯吡格雷进行治疗。比较两组治疗效果、治疗前后血清同型半胱氨酸水平及不良反应发生率。结果观察组总有效率为93.33%,显著高于对照组的73.33%,差异有统计学意义(P0.05)。两组治疗前血清同型半胱氨酸水平比较,差异无统计学意义(P0.05);两组治疗后血清同型半胱氨酸水平均低于治疗前,差异有统计学意义(P0.05),观察组治疗后血清同型半胱氨酸水平低于对照组,差异有统计学意义(P0.05)。观察组不良反应发生率低于对照组,差异有统计学意义(P0.05)。结论依达拉奉联合硫酸氢氯吡格雷治疗急性脑梗死临床效果显著,能降低同型半胱氨酸水平,且不良反应发生率低,值得临床推广。  相似文献   
4.
5.
[目的] 系统研究参麦注射液体外抗氧化性能。[方法] 采用铁还原抗氧化能力 (FRAP)法、1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法、一氧化氮(NO)自由基清除法、过氧化氢(H2O2)清除法、亚铁(Fe2+)离子螯合法分别测试不同稀释倍率参麦注射液的总抗氧化能力、DPPH·清除活性、NO·清除活性、H2O2清除活性和Fe2+离子螯合活性,并将结果与0.1mg/mL 2,6-二叔丁基对甲酚(BHT)、10 mmol/L水溶性维生素E(Trolox)和10%柠檬酸的结果进行比较。[结果] 参麦注射液具有一定的体外抗氧化能力,总抗氧化能力和对自由基清除活性均呈浓度正依赖性;10倍稀释参麦注射液总抗氧化能力显著低于BHT和Trolox (P<0.01),但高于柠檬酸(P<0.01);参麦注射液对不同自由基清除能力存在差异,其强弱顺序为:NO·[(54.4±6.6)%] > Fe2+离子螯[(42.6±3.2)%] > DPPH·[(36.2±2.8)%] > H2O2[(23.5±1.2)%]。[结论] 参麦注射液体外抗氧化活性研究将为其抗氧化药理学机制提供了实验依据。  相似文献   
6.
Isolators are commonly used in filling operations of pharmaceutical products. To ensure an aseptic inner environment, isolators are regularly sterilized with vaporized hydrogen peroxide. However, despite extensive purging with air, some residual H2O2 remains within the isolator atmosphere and may thus end up in the liquid pharmaceutical drug product, which subsequently may cause oxidation and impact the product’s safety and efficacy. We aimed to evaluate the extent of this phenomenon and to model it. For that purpose, we studied the diffusion of H2O2 into water contained in small recipients exposed to the atmosphere of a H2O2-sterilized small-scale test isolator. Based on the results, a mechanistic model was proposed to estimate the quantity of H2O2 in the product, taking into account the time, filling volume, H2O2 concentration, and a configuration factor. Afterward, this model was challenged by filling water at a manufacturing scale, and we observed that the diffusion model could predict the trend of increasing H2O2 concentration. However, a consistent difference in H2O2 concentration between the model and the experimental results was observed, suggesting the contribution of another parameter. Our results can be used to predict more accurately H2O2 concentration in a pharmaceutical product at the manufacturing level.  相似文献   
7.
Introduction: Hydrogen sulfide (H2S) is found in petroleum, natural gas, and decaying organic matter. Terrorist groups have attempted to use it in enclosed spaces as a chemical weapon. Mass casualty scenarios have occurred from industrial accidents and release from oil field sites. There is no FDA approved antidote for sulfide poisoning. We have previously reported that intravenous cobinamide is effective for sulfide poisoning. A rapid-acting antidote that is easy to administer intramuscularly (IM) would be ideal for use in a prehospital setting. In this study, we assessed survival in sulfide-poisoned swine treated with IM cobinamide.

Methods: Eleven swine (45–55?kg) were anesthetized, intubated, and instrumented with continuous femoral and pulmonary artery pressure monitoring. After stabilization, anesthesia was adjusted such that animals ventilated spontaneously with a FiO2 of 0.21. Sodium hydrosulfide (NaHS, 8?mg/mL) was infused intravenously at 0.9?mg/kg.min until apnea or severe hypotension. Animals were randomly assigned to receive cobinamide (4?mg/kg), or no treatment at the apnea/hypotension trigger. The NaHS infusion rate was sustained for 1.5?min post trigger, decreased to 0.2?mg/kg.min for 10?min, and then discontinued.

Results: The amount of NaHS required to produce apnea or hypotension was not statistically different in both groups (cobinamide: 9.0?mg/kg ±6.1; saline: 5.9?mg/kg ±5.5; mean difference: ?3.1, 95% CI: ?11.3, 5.0). All of the cobinamide treated animals survived (5/5), none of the control (0/6) animals survived (p?Conclusion: Intramuscular cobinamide was effective in improving survival in this large swine model of severe hydrogen sulfide toxicity.  相似文献   
8.
Antibody aggregates are a potential risk for immunogenicity; therefore, rational approaches to improve associated aggregation properties need to be developed. Here, we report the amino acid region responsible for aggregation initiation. Two types of therapeutic IgG1 antibody monomer samples were prepared: IgG1 mAb40-3M stored at 40°C for 3 months, which existed in monodisperse state, and the monomer mAb65-5m, which was dissociated from small soluble aggregates by heating at 65°C for 5 min. Hydrogen deuterium exchange mass spectrometry of mAb40-3M identified 2 sites in the Fc region (site 1, F239-M256; site 2, S428-G450) with increased exchange rates. Site 1 includes a region reported as being susceptible to structural change induced by stress. Exposure of site 1 was undetected after 2 months of storage at 40°C but was subsequently detectable after 3 months. As site 2 is spatially close to site 1, the structural change of site 1 could propagate site 2. Besides these 2 regions, hydrogen deuterium exchange mass spectrometry of mAb65-5m identified an exposure of I257-W281 in Fc (site 3), within which a peptide sequence with high aggregation tendency was discovered. We thus concluded that exposure of site 3 is a trigger for the association of a partially denatured antibody.  相似文献   
9.
Mutations in the MBOAT7 gene have been described in 43 patients, belonging to 18 families, showing nonspecific clinical features (intellectual disability [ID], seizures, microcephaly or macrocephaly, and mild to moderate cerebellar atrophy) that make the clinical diagnosis difficult. Here we report the first Italian patient, a 22.5‐year‐old female, one of the oldest reported, born to apparently consanguineous parents. She shows severe ID, macrocephaly, seizures, aggressive outbursts, hyperphagia. We also documented progressive atrophy of the cerebellar vermis, that appeared not before the age of 7. The whole‐exome sequencing of the trio identified a novel homozygous variant c.1057_1058delGCinsCA (p.Ala353His) in the MBOAT7 gene. The variant is considered to be likely pathogenic, since it is absent from population database and it lies in a highly conserved amino acid residue. This disorder has a neurometabolic pathogenesis, implicating a phospholipid remodeling abnormalities. A brain hydrogen‐magnetic resonance spectroscopy (H‐MRS) examination in our patient disclosed a peculiar neurometabolic profile in the cerebellar hemispheric region. This new finding could address the clinical suspicion of MBOAT7‐related disorder, among the wide range of genetic conditions associated with ID and cerebellar atrophy. Moreover, the documented progression of cerebellar atrophy and the worsening of the disease only after some years open to the possibility of a therapeutic window after birth.  相似文献   
10.
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