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131.
目的 通过对正常和心血管疾病状态下的大鼠进行连续超声心动图检测,获得客观准确的大鼠心脏超声参数的变化趋势。方法 建立缺血性心肌梗死和压力负荷增高诱导心肌肥厚的大鼠模型,分别在术前、术后1、2和4周进行超声心动图检测,在相同时间点对正常大鼠进行超声心动图检测,并记录超声参数数据。结果 正常大鼠各心脏参数随时间的变化均有所升高,属正常生长状态。心肌梗死大鼠心脏变化以心室重构和功能障碍为主,心室内径和心室容积随时间变化显著增加,射血分数和短轴缩短率显著降低,差异均有统计学意义(P<0.05)。心肌肥厚大鼠心脏变化以形态改变为主,左室前、后壁厚度随着时间的延长显著增加,收缩末期容积显著下降,射血分数和短轴缩短率代偿性升高,差异均有统计学意义(P<0.05)。结论 应用超声心动图可获得正常和疾病状态下较为客观准确的大鼠心脏超声数据,为后续应用大鼠实验模型研究各种心血管疾病提供了数据参考。  相似文献   
132.
目的探讨纤维鼻咽镜联合切割吸引器对腺样体肥大患儿血清肿瘤坏死因子-α(TNF-α)、白细胞介素-4(IL-4)、白三烯B4(LTB4)水平的影响。方法选取2017年2月至2019年7月在本院进行治疗的腺样体肥大患儿80例,按照随机数字表法分为观察组与对照组,各40例。对照组行传统经口腺样体刮除术,观察组行纤维鼻咽镜联合切割吸引器切除术,比较两组患儿血清TNF-α、IL-4、LTB4水平。结果术后,两组血清TNF-α、IL-4、LTB4水平均降低,且观察组低于对照组,差异有统计学意义(P<0.05);观察组术中出血量少于对照组,鼻腔恢复通气与咽痛持续时间短于对照组,差异有统计学意义(P<0.05);观察组并发症发生率略低于对照组,差异无统计学意义。结论纤维鼻咽镜联合切割吸引器的应用可减少术中出血量,促进恢复,降低腺样体肥大患儿血清TNF-α、IL-4、LTB4水平,且安全性较高。  相似文献   
133.
Asymptomatic Alzheimer''s disease (ASYMAD) subjects are individuals characterized by preserved cognition before death despite substantial AD pathology at autopsy. ASYMAD subjects show comparable levels of AD pathology, i.e. β-amyloid neuritic plaques (Aβ-NP) and tau-neurofibrillary tangles (NFT), to those observed in mild cognitive impairment (MCI) and some definite AD cases. Previous clinicopathologic studies on ASYMAD subjects have shown specific phenomena of hypertrophy in the cell bodies, nuclei, and nucleoli of hippocampal pyramidal neurons and other cerebral areas. Since it is well established that the allele APOε4 is a major genetic risk factor for AD, we examined whether specific alleles of APOE could be associated with the different clinical outcomes between ASYMAD and MCI subjects despite equivalent AD pathology. A total of 523 brains from the Nun Study were screened for this investigation. The results showed higher APOε2 frequency (p < 0.001) in ASYMAD (19.2%) vs. MCI (0%) and vs. AD (4.7%). Furthermore, higher education in ASYMAD vs. MCI and AD (p < 0.05) was found. These novel autopsy-verified findings support the hypothesis of the beneficial effect of APOε2 and education, both which seem to act as contributing factors in delaying or forestalling the clinical manifestations of AD despite consistent levels of AD pathology.  相似文献   
134.
目的探讨高血压心肌肥厚患者心脏交感神经分布与神经元轴突生长抑制因子勿动蛋白A(neurite out-growth inhibitor-A,Nogo-A)的表达变化。方法从我院老年患者尸体标本库中,随机入选男性高血压患者10例,并根据患者去世前1周心脏超声结果分为心肌肥厚组4例和非心肌肥厚组6例。检测超声心动图,并计算左心室重量指数。免疫组织化学分析测定酪氨酸羟化酶(tyrosine hydroxylase,TH)与Nogo-A的表达。结果与非心肌肥厚组比较,心肌肥厚组患者室间隔厚度、左心室后壁厚度、左心室重量指数明显升高(P<0.05);心肌肥厚组患者心肌TH阳性表达明显降低[(6.35±3.85)%υs(22.17±8.19)%,P<0.05],Nogo A表达明显增加[(11.34±7.16)%υs(2.17±4.10)%,P<0.05]。心肌肥厚患者心肌Nogo-A表达与心肌TH表达呈负相关(r=-0.33,P<0.05)。结论老年高血压心肌肥厚患者心肌交感神经分布减低,然而心肌神经元轴突生长抑制因子Nogo-A表达增加,两者间存在密切相关性。  相似文献   
135.
Mesterolone is a synthetic oral anabolic androgenic steroid used to treat hypogonadism. There are frequent reports of mesterolone abuse in human and equine sports to increase muscle mass and strength. However, limited information is available about how this drug exerts its effects on skeletal muscle. Satellite cells (SCs) are mononuclear myogenic stem cells that contribute to postnatal muscle growth and repair. As SC activation and subsequent differentiation to new myonuclei is a major event during muscle hypertrophy, this study investigated the influence of mesterolone on SC distribution within the pectoralis muscle of chickens. Specifically, this study tested the hypotheses that mesterolone induces avian skeletal muscle hypertrophy, and that mesterolone increases the number of SCs in avian skeletal muscle. Robust immunocytochemical techniques and morphometric analyses were used to calculate the numbers of SCs and myonuclei. Also, DNA concentration and Pax7 protein levels were measured to confirm immunocytochemical findings. Mesterolone significantly increased pectoralis mass and fiber size. All SC indices and number of myonuclei increased significantly by mesterolone administration. In addition, greater DNA concentration and Pax7 protein expression were found in mesterolone‐treated birds. This study indicates that mesterolone can induce avian skeletal muscle hypertrophy and that this is correlated with increased number of SCs. We suggest that SCs are key cellular intermediaries for mesterolone‐induced muscle hypertrophy. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
136.
137.
The present investigation examines the association of angiotesin I converting enzyme (ACE) genotypes with blood pressure and heart weight in an F2 population of rats derived from a cross between spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. ACE genotype of rats in the F2 population was determined using a microsatellite polymorphism. Our investigation revealed that cardiac mass was not correlated with blood pressure at 12 weeks of age within the SHR, WKY, F1 or F2 groups of rats. In male rats, ACE genotype accounted for approximately 20% of the difference in mean blood pressure between SHR and WKY rats. There was no effect in females. It was also responsible for 21%-29% of the difference in heart weight both in female and male animals. The allele derived from the SHR parent appeared recessive to the allele from WKY parent for both heart weight and blood pressure. These results suggest that a gene in the region of the ACE locus is one of the genetic factors influencing blood pressure and heart weight in SHR.  相似文献   
138.
Perioperative medical management is challenging due to the rising complexity of patients presenting for surgical procedures. A key part of preoperative optimization is appropriate management of long-term medications, yet guidelines and consensus statements for perioperative medication management are lacking. Available resources utilize the recommendations derived from individual studies and do not include a multidisciplinary focus or formal consensus. The Society for Perioperative Assessment and Quality Improvement (SPAQI) identified a lack of authoritative clinical guidance as an opportunity to utilize its multidisciplinary membership to improve evidence-based perioperative care. SPAQI seeks to provide guidance on perioperative medication management that synthesizes available literature with expert consensus. The aim of this Consensus Statement is to provide practical guidance on the preoperative management of endocrine, hormonal, and urologic medications. A panel of experts with anesthesiology, perioperative medicine, hospital medicine, general internal medicine, and medical specialty experience was drawn together and identified the common medications in each of these categories. The authors then utilized a modified Delphi approach to critically review the literature and generate consensus recommendations.  相似文献   
139.
140.
目的探索改良边缘切除法、楔形切除法在小阴唇肥大缩小术中的临床应用效果。方法选取2017年9月-2019年9月在郑州大学第三附属医院行小阴唇肥大缩小术的47例双侧小阴唇肥大患者,根据小阴唇肥大的程度和小阴唇形态分型以及患者需求选择改良边缘切除法22例,楔形切除法25例。比较两组患者的术中出血量、手术时间、切口愈合情况及手术满意度,采用女性性功能指数简表评分(FSFI-6量表)对患者的性生活情况进行评估。结果两组间手术时间比较显示边缘切除法手术时间较楔形切除法短(P<0.05),但两组间术中出血无明显差异(P>0.05)。两组患者术后满意度均较高。两组患者术后性生活湿润度、满意度评分及总评分较术前提高,差异有统计学意义(P<0.05)。两组患者的术前术后性欲望、性唤醒、性高潮频率方面表现无差异(P>0.05)。结论两种小阴唇肥大缩小术均可有效治疗小阴唇肥大,医生需结合患者小阴唇肥大类型和个人审美要求制定设计个性化的治疗方案。  相似文献   
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