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1.
《Survey of ophthalmology》2023,68(5):940-956
Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies.  相似文献   
2.
通过查阅古代本草文献中大黄的记载,梳理大黄的性味归经与功效,归纳大黄的用药特点。大黄味苦性寒,主归胃、大肠经,具有攻积滞,行土郁,清火热,解热毒,凉血热,下瘀血,通经脉,祛痰湿,利水道,退黄疸,外用解毒消肿止痛之功效;主治脏腑积滞、痰热腑实、癥瘕积聚、痞满燥实、热结便秘、瘟疫发斑、阳狂谵语、痢下赤白、里急腹痛、口舌生疮、齿龈肿痛、湿热黄疸、小便淋漓、热毒疮痈、水火烫伤、瘀血诸证及血热妄行之各种出血证。从现代药理学角度分析,大黄具有泻下与止泻双向调节、保护胃及十二指肠黏膜、护肝利胆、保护胰腺细胞及功能、活血、止血、调节血脂、保护心脑血管、保护肾脏功能、抗炎抑菌、抗病毒、抗肿瘤、免疫调节等作用。  相似文献   
3.
背景:儿童新型冠状(新冠)病毒Omicron变异株流行期间,免疫抑制状态儿童新冠病毒清除时间定量分析研究较少。 目的:探讨新冠病毒Omicron株感染后免疫抑制和非免疫抑制儿童病毒清除的时间差别,为公共卫生政策制定和精准疫情防控措施提供临床数据。 设计:回顾性队列研究。 方法:以新冠病毒Omicron变异株感染住院患儿为队列人群,分为免疫抑制组和非免疫抑制组,免疫抑制分为绝对免疫抑制、相对免疫抑制和实施免疫抑制疗法,以免疫抑制组病例的性别、年龄和新冠病毒感染的分型与非免疫抑制组行1∶3匹配。以鼻咽拭子新冠病毒PCR检测拷贝数阈(Ct)值≥35为队列终点。 主要结局指标:新冠病毒清除时间。 结果:2022年4月12日至2022年5月12日在上海市新冠病毒感染定点收治医院符合本文共同纳入和排除标准的连续病例728例。免疫抑制组33例,其中绝对免疫抑制8例,相对免疫抑制23例,接受免疫抑制疗法2例(不包括绝对和相对免疫抑制患儿)。非免疫抑制组匹配后99例。2组临床症状、新冠病毒感染治疗和疫苗接种次数差异均无统计学意义。免疫抑制组和非免疫抑制组新冠病毒清除时间分别为(16.5±6.8)和(10.3±4.4)d,差异有统计学意义。免疫抑制组和非免疫抑制组新冠病毒感染轻型病例病毒清除时间分别为(14.0 ± 8.3)和(9.7 ± 3.1)d,普通型病例病毒清除时间分别为(18.3 ± 4.9)和(11.2 ± 5.9)d,差异均有统计学意义。2组单日病毒清除率在第9~14天时差异有统计学意义(P为0.005~0.039)。2组普通型病例单日病毒清除率在第10~15天时差异有统计学意义。免疫抑制组新冠病毒感染2周后核酸检测再次呈阳性3例(9%),临床分型均较前轻,3例均未接种新冠疫苗。 结论:Omicron株感染的免疫抑制患儿病毒清除时间较非免疫抑制患儿显著延长,主要反映在第9~14天,免疫抑制患儿病毒复阳风险高,提示需要更长的隔离时间和转阴后严格的病毒监测。  相似文献   
4.
卜兰  刘菲  熊亮  彭成 《世界中医药》2020,15(9):1237-1246
益母草属植物中的化合物类型多样、结构丰富,其中萜类化合物是目前发现数量最多的一类,同时具有广泛的生物活性。因此,作者对益母草属萜类化合物及其药理活性进行总结归纳,为该属萜类化合物的进一步研究提供参考。  相似文献   
5.
《中国现代医生》2020,58(4):189-192
地黄饮子是治疗暗痱证的重要方剂,但历代医家对其具体组方多有歧义,病因病机也较为混乱,令人难以理解与把握。其中《圣济总录》卷五十一方为常用方,主治瘖痱证,现代医家常将其应用于中风后遗症的诊疗中。本文从组方意义、药理机制、现代临床应用叙述地黄饮子治疗暗痱证的研究概况,以期更好地服务于临床。  相似文献   
6.
牡丹皮为毛茛科植物牡丹的干燥根皮,临床常用中药,具有活血化瘀,清热凉血之功效。系统总结了近年来对牡丹皮的化学、提取、分析及药理等现代研究与应用基本现状,发现牡丹皮中含有酚及酚苷类、单萜及其苷类、三萜等大量复杂类型化学成分,且牡丹皮及所含牡丹酚及其糖苷类成分具有较强的抑菌抗炎、抗肿瘤、抗心律失常、降糖、激活机体免疫系统及保护心血管等多种作用。  相似文献   
7.
Collective motion of active matter is ubiquitously observed, ranging from propelled colloids to flocks of bird, and often features the formation of complex structures composed of agents moving coherently. However, it remains extremely challenging to predict emergent patterns from the binary interaction between agents, especially as only a limited number of interaction regimes have been experimentally observed so far. Here, we introduce an actin gliding assay coupled to a supported lipid bilayer, whose fluidity forces the interaction between self-propelled filaments to be dominated by steric repulsion. This results in filaments stopping upon binary collisions and eventually aligning nematically. Such a binary interaction rule results at high densities in the emergence of dynamic collectively moving structures including clusters, vortices, and streams of filaments. Despite the microscopic interaction having a nematic symmetry, the emergent structures are found to be polar, with filaments collectively moving in the same direction. This is due to polar biases introduced by the stopping upon collision, both on the individual filaments scale as well as on the scale of collective structures. In this context, positive half-charged topological defects turn out to be a most efficient trapping and polarity sorting conformation.

Collective motion of active matter is ubiquitous, with observations ranging from flocks of birds (1) and schools of fish (2) to propelled colloids (3). The interactions between agents in such systems lead to the formation of complex structures including clusters, swirls, or lanes of agents moving coherently (4). The structure of the emerging patterns strongly depends on both the agents’ shape and their velocity alignment mechanism. A particular case is that of elongated microscopic particles that translate along their major axis in a quasi-two-dimensional environment and only interact upon collision (5, 6). In the context of cytoskeletal systems, gliding actin filaments or microtubules propelled by molecular motors are found to be able to readily crawl over each other and only retain a weak level of alignment upon binary collisions, which eventually leads at high densities to a diverse set of patterns (7). Such resulting patterns are found to be strongly dependent on this weak microscopic alignment interaction, and therefore, even slightly tuning it causes the system to switch between polar and nematic phases, separated by a coexistence regime (8, 9). Observed structures in cytoskeletal systems with weak to moderate interactions include nematic lanes, polar waves, and vortices (1012). Conversely, pattern formation in systems of elongated bacteria or granular matter is often based on hard interactions with a strong steric component (1318). In this repulsion-dominated regime, particles are unable to crawl over each other and must stop upon collision. In the limiting case of spherical self-propelled particles, this kind of steric interaction can lead to a stable phase separation between stuck and moving particles, the so-called motility induced phase separation (MIPS) (19). On the other hand, in the case of elongated particles, steric effects can still act as velocity aligning mechanisms. As orientation mismatches are unstable, particles end up aligning and this leads to flocking behavior rather than to phase separation (5, 2025). This latter case, in which strong steric constraints dominate binary interactions but alignment is still present, is poorly understood, and how modeling has to be extended to account for the emergent collective behavior of elongated, flexible agents with volume exclusion also remains still under debate (2630). This is partly due to the lack of microscopic experimental systems allowing to explore this regime. Semiflexible cytoskeletal filaments would be the best candidate, but their volume exclusion is usually too weak. However, having them propelled by motors immobilized on a fluid membrane would be a promising route to bridge this experimental gap (31).Here, we enforce a steric repulsion-dominated interaction, leading to alignment between actin filaments by coupling myosin motors to a fluid-supported lipid bilayer. Because of the slippage of the motors on the membrane, the force propelling the filaments is too weak to enable filaments to crawl over each other and thus effectively implements a repulsion-dominated regime, with filaments stopping upon collisions. Eventually, however, because of the thermal fluctuations of their tips, filaments can align and resume motion. The experimental realization of such a microscopic binary interaction, based on volume exclusion, enables us to observe and quantify the resulting pattern formation process in a system of active semiflexible filaments. We then first characterize the interaction at the single filament scale, showing that it leads to nematic alignment. As the filaments’ density is increased, patterns of collective motion emerge, ranging from clusters to thick streams and vortices. Despite the nematic collision rule, we find the emerging structures to be locally polar. The repulsion-dominated interaction indeed introduces a polar bias not only due to the tendency of active filaments or clusters to keep moving together after a polar collision but also by forcing filaments with similar orientation to stop and accumulate when encountering an obstacle. In particular, at high densities, such an interaction leads to the formation of transient local +1/2 topological defects, which act as wedges and, therefore, effectively trap and polarity-sort motile filaments. We interpret this trapping mechanism as an analog of MIPS for elongated self-propelled particles.  相似文献   
8.
9.
目的:量化拔戳揉捻手法治疗肱骨外上髁炎的生物力学参数,探讨患者个体特征对手法操作的影响。方法:选取2019年7月至2020年2月就诊的肱骨外上髁炎患者40例,男18例,女22例,年龄20~50(34.37±8.41)岁,病程1~11(6.05±2.71)个月,采用生物力学传感器测量同一手法术者对患者患侧肘关节实施拔戳揉捻手法的生物力学参数,量化生物力学参数并研究参数间可能存在的相关性,同时采集患者个体特征学参数,分析不同患者个体特征对生物力学参数的影响。结果:拔戳揉捻手法各阶段生物力学参数量化结果,旋后揉捻力(31.17±2.99) N,屈曲拔按力(44.99±2.38) N,旋前揉捻力(31.03±2.75) N,拔直戳按力(48.75±2.09) N,参数相关性分析显示旋后揉捻力与旋前揉捻力参数间存在显著正相关,屈曲拔按力与拔直戳按力参数间存在显著正相关。对患者个体特征参数与手法生物力学参数进行多元线性回归分析显示,患者的体重与旋后揉捻力间呈显著相关,患者肘部压痛值与屈曲拔按力存在显著相关,患者病程与拔直戳按力呈显著相关。结论:拔戳揉捻手法治疗肱骨外上髁炎在体操作力大小具有一定的标准,手法各阶段术者操作的作用力趋势具有系统性,患者的体重、患肘压痛情况与病程是影响拔戳揉捻手法操作的重要因素。  相似文献   
10.
Maladaptive daydreaming (MD) is an immersive fantasy activity that leads to distress and socio-occupational dysfunction. MD has many features suggestive of behavioural addiction, but research exploring the phenomenology of this clinical construct is limited. MD has also been purported to be a maladaptive strategy to cope with distress, but often leads to uncontrollable absorption in fantasy world, social withdrawal and neglected aspects of everyday life. In this paper, we report the case of a 16-year-old boy who developed internet gaming disorder and MD after experiencing cyberbullying from his peers. The patient engaged in vivid, fanciful imagery that lasted for hours, leading to social dysfunction and academic deterioration. Baseline assessment revealed a Maladaptive Daydreaming Scale-16 score of 65 (cut-off 50) and an Internet Gaming Test-20 score of 86 (cut-off 71). The patient was managed primarily with psychological intervention. The therapy focused on behaviour modification and cognitive restructuring. Patients in clinical setting should be questioned about MD when presenting with excessive use of technology or other forms of behavioural addictions. Further studies are necessary to determine the biopsychosocial factors of MD and its correlates. There is also a need to study treatment and management approaches for treating MD.  相似文献   
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