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BackgroundVisually induced dizziness can develop as a sequala of a vestibular disorder and is characterized by symptoms of nausea, dizziness, and imbalance in rich visual environments such as supermarkets and shopping malls. To date the mechanisms underlying visually induced dizziness are poorly understood.Research questionWhat are the characteristics of visual fixations and postural sway in adults with visually induced dizziness compared to healthy adults when exposed to increasingly complex visual environments?MethodsWe recruited 20 adults with visually induced dizziness and 20 healthy adults to this cross-sectional exploratory study. Participants were instructed to maintain gaze on letters projected on a large screen with backgrounds of differing visual complexity. The number of visual refixations, movement of the centre of pressure, and movement of the head and body centres of mass were recorded.ResultsAdults with visually induced dizziness showed a significantly higher number of visual refixations (F= 10.592, p < 0.01), and increased mean velocity of head and body centres of mass movement (F= 14.034, p < 0.01 and F= 6.553, p < 0.05 respectively) compared to healthy adults.SignificanceAdults with visually induced dizziness exhibited visual fixational instability and increased postural and head sway compared to healthy adults. This was mainly observed in conditions with complex and moving backgrounds. This may account for reports from adults with visually induced dizziness of worsening symptoms in busy environments. The results from the study may assist in guiding intervention development to reduce symptoms of visually induced dizziness.  相似文献   
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《Drug discovery today》2022,27(1):223-233
Approaches based on animal and two-dimensional (2D) cell culture models cannot ensure reliable results in modeling novel pathogens or in drug testing in the short term; therefore, there is rising interest in platforms such as organoids. To develop a toolbox that can be used successfully to overcome current issues in modeling various infections, it is essential to provide a framework of recent achievements in applying organoids. Organoids have been used to study viruses, bacteria, and protists that cause, for example, respiratory, gastrointestinal, and liver diseases. Their future as models of infection will be associated with improvements in system complexity, including abilities to model tissue structure, a dynamic microenvironment, and coinfection.Teaser.Organoids are a flexible tool for modelling viral, bacterial and protist infections. They can provide fast and reliable information on the biology of pathogens and in drug screening, and thus have become essential in combatting emerging infectious diseases.  相似文献   
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目的:观察肠炎清合剂对慢性复发型溃疡性结肠炎(UC)大肠湿热证患者诱导缓解效果及维持治疗对复发的影响,并从神经-内分泌-免疫炎症网络方面探讨了其作用机制。方法:将112例符合要求的患者随机分成对照组55例和观察组57例。对照组内服美沙拉嗪肠溶片,1.0 g/次,4次/d;Mayo评分系统≥7分者,加服醋酸泼尼松片,0.75 mg·kg^-1·d^-1;加用双歧杆菌活菌散剂,1包/次,2次/d,餐后温水冲服。观察组在对照组治疗的基础上服用肠炎清合剂,1包/次,分早晚2次服用。两组疗程均为连续治疗6周,再每周门诊复诊1次。进入缓解期后,两组患者均给予美沙拉嗪肠溶片,0.5 g/次,3次/d,维持治疗;观察组仍内服肠炎清合剂内服,至大肠湿热证评分减少≥90%以上。记录进入6周内缓解期的人数和缓解时间;进行治疗前后结肠镜检查,并进行Geboes指数和Baron法评价;进行治疗前后大肠湿热证评分和Mayo评分;检测治疗前后外周血白细胞介素-6(IL-6),IL-8,IL^-10,IL^-17,血管活性肠肽(VIP),胃动素(MTL)和神经肽Y(NPY);随访24周,记录复发情况。结果:经6周治疗后,观察组临床有效率为100%,黏膜愈合率为96.4%,均分别高于对照组的89.09%和81.82%(P<0.05),两组患者内镜应答率均为100%;经6周治疗后,观察组临床缓解率为91.23%,高于对照组的76.36%(χ2=4.581,P<0.05),观察组平均缓解时间短于对照组(P<0.01);治疗后观察组结肠黏膜评分,Geboes指数、大肠湿热证评分和Mayo评分均低于对照组(P<0.01);观察组患者外周血IL-6,IL-8和IL^-17水平均低于对照组(P<0.01),IL^-10水平高于对照组(P<0.01);观察组患者外周血VIP,MTL水平均低对照组(P<0.01),NPY水平高于对照组(P<0.01);观察组复发率为17.54%,低于对照组的38.18%(χ2=5.955,P<0.05);观察组平均复发时间长于对照组(P<0.01)。结论:在常规西医治疗的基础上,肠炎清合剂用于慢性复发型UC大肠湿热证的治疗,可诱导病情缓解,缩短病程,并能降低复发率,推迟复发时间,并对神经-内分泌-免疫炎症网络具有调节作用,从而可改善病情。  相似文献   
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目的探讨冬虫夏草预防糖尿病大鼠对比剂肾病的机制。方法SD大鼠80只,腹腔注射链脲佐菌素(60 mg/kg)建立糖尿病模型,并随机分为对照组(C组)、对比剂肾病组(CIN组)、冬虫夏草低剂量组(L组)、冬虫夏草标准剂量组(M组)和冬虫夏草强化剂量组(H组)。L组、M组、H组大鼠分别给予冬虫夏草(2.0、2.5、3.0 g/kg)灌胃,C组、CIN组则以等量生理盐水灌饲,连续7天。7天后检测SCr、BUN、尿蛋白排泄率(UAE)、一氧化氮(NO)、超氧化物歧化酶(SOD)、丙二醛(MDA)、总抗氧化能力(T-AOC)、中性粒细胞明胶酶相关脂质运载蛋白(NGAL)、肾损伤分子1(KIM-1)及IL-18。取左肾测病理和氧化应激指标;右肾用于Western Blot检测抗凋亡蛋白和促凋亡蛋白(包括:Bcl-2、Bax、Caspase-3、Caspase-9、p-Akt、p-mTOR、p-ERK、p-JNK、p-P70S6K)表达。结果与C组比较,CIN组SCr、BUN、UAE、MDA、NAGL、KIM-1、IL-18均明显升高,NO、T-SOD降低(P<0.05)。与CIN组比较,L组、M组、H组SCr、BUN、UAE、MDA均明显降低,NO、T-SOD升高(P<0.05);L组、H组NAGL、IL-18、降低(P<0.01),其中H组KIM-1均明显降低(P<0.01)。与L组、M组比较,H组SCr、BUN、UAE、MDA、NGAL、KIM-1、IL-18明显降低,NO、T-SOD升高(P<0.05)。与C组比较,CIN组Bcl-2、P-Akt、P-mTOR、P-P70S6K、P-ERK蛋白表达增加,Bax、P-JNK、Caspase-3、Caspase-9蛋白表达减少(P<0.05)。与CIN组比较,Bcl-2、P-Akt、P-mTOR、P-P70S6K、P-ERK蛋白表达在L组、M组、H组逐渐增加,其中H组最高(P<0.05),Bax、P-JNK、Caspase-3、Caspase-9蛋白表达L组、M组、H组逐渐减少,H组表达量最少(P<0.05)。结论冬虫夏草通过抗氧化应激、抑制脂质过氧化反应、抗凋亡等途径对糖尿病大鼠对比剂肾病发挥较好的保护作用,冬虫夏草强化剂量组优于低剂量组和标准剂量组。  相似文献   
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The development of patient‐specific induced pluripotent stem cells (iPSCs) offered interesting insights in modeling the pathogenesis of Charcot‐Marie‐Tooth (CMT) disease and thus we decided to explore the phenotypes of iPSCs derived from a single CMT patient carrying a mutant ATP1A1 allele (p.Pro600Ala). iPSCs clones generated from CMT and control fibroblasts, were induced to differentiate into neural precursors and then into post‐mitotic neurons. Control iPSCs differentiated into neuronal precursors and then into post‐mitotic neurons within 6‐8 days. On the contrary, the differentiation of CMT iPSCs was clearly defective. Electrophysiological properties confirmed that post‐mitotic neurons were less mature compared to the normal counterpart. The impairment of in vitro differentiation of CMT iPSCs only concerned with the neuronal pathway, because they were able to differentiate into mesendodermal cells and other ectodermal derivatives. ATP1A1 was undetectable in the few neuronal cells derived from CMT iPSCs. ATP1A1 gene mutation (p.Pro600Ala), responsible for a form of axonal CMT disease, is associated in vitro with a dramatic alteration of the differentiation of patient‐derived iPSCs into post‐mitotic neurons. Thus, the defect in neuronal cell development might lead in vivo to a decreased number of mature neurons in ATP1A1‐CMT disease.  相似文献   
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