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排序方式: 共有9733条查询结果,搜索用时 15 毫秒
1.
目的探究磁共振成像(MRI)常规序列与三维扰相脂肪抑制梯度回波(3D-WATS)序列对早期类风湿性关节炎手关节病变的诊断价值。方法前瞻性选取2019年1月至2020年1月丹东市第一医院收治的80例疑似早期类风湿关节炎(RA)手关节病变患者作为研究对象。所有患者入院后分别行MRI常规序列及3D-WATS序列诊断,将诊断结果与病理结果对照,分析不同序列对早期RA手关节病变检出情况以及诊断的敏感性、准确性与特异性。结果病理诊断结果显示,80例患者中52例确诊为RA手关节病变阳性,28例为阴性;经3D-WATS序列诊断显示RA手关节病变阳性49例,阴性26例;MRI常规序列检出RA手关节病变阳性40例、阴性20例。3D-WATS序列诊断RA手关节病变的敏感性(94.23%)、特异性(92.86%)及准确率(93.75%)均显著高于MRI常规序列诊断(76.92%,71.43%,75.00%),差异均有统计学意义(P <0.05);3D-WATS序列对关节滑膜炎、骨侵蚀检出率(87.50%,66.25%)明显高于MRI常规序列(68.75%,50.00%),差异均有统计学意义(P <0.05)。结论 MRI 3D-WATS序列诊断早期类风湿性关节炎手关节病变敏感性、特异性及准确率高,能够有效检出关节滑膜炎、骨侵蚀等情况,优于MRI常规序列诊断,能够为临床治疗提供可靠依据,值得临床推广应用。 相似文献
2.
目的评价现有镍钛锉在根管预备中的使用效果,探讨根管预备中锉的最佳使用顺序。方法使用Excel 2016,推导特定直径和锥度的锉表面积和体积计算公式。以根管体积和表面积增长率为主要指标,结合折线图和锥度坐标图进行数值模拟。结果在纳入的现有26种根管锉产品中,vTaper推荐的预备顺序平均体积增长率最低。3+1 (即1根通道锉与3根成形锉)、3+2 (即2根通道锉与3根成形锉)、4+1 (即1根通道锉与4根成形锉)以及4+2 (即2根通道锉与4根成形锉)共4种模式对应的最佳根管锉使用顺序依次为2002—2003—2004—2504—3004、 2002—1803—1804—2004—2504—3004、 2002—1703—1704—2004—2504—3004;2002—1503—1703—1704—2004—2504—3004。结论根据数据模拟,纳入的现有镍钛锉系统中,使用#20 K锉的vTaper系统的预备顺序最佳。通过推导得出的4种最佳顺序的根管体积和表面积增长率的平均值和方差明显小于大多数现有的系统,为后续实验提供基础,并有助于提高根管治疗的成功率,减少并发症。 相似文献
3.
《The Egyptian Rheumatologist》2022,44(4):361-365
Juvenile Idiopathic Arthritis (JIA) is a multi-factorial disease influenced both by environmental and genetic factors. Progressive pseudorheumatoid dysplasia (PPD) is a rare autosomal recessive genetic disorder affecting multiple joints, mimicking JIA. Aim of the work: to reveal the frequency of HLA-DR types among the studied patients and to correlate the different allele variations clinically. Patients and methods: Thirty JIA patients, in addition to 15 molecularly diagnosed PPD patients were subjected to full history taking and clinical examination. HLA-DRB1 typing was performed to 24/30 JIA and 12/15 PPD cases and thirty healthy age and sex matched children who were included as a control group. Results: The JIA patients were 22 females and 8 males with mean age of 15.8 ± 1.96 years and disease duration 5.3 ± 4.4 years. PPD patients were 8 males and 7 females with mean age of 8.7 ± 3.06 years and disease duration 3.95 ± 2.68 years. A significant frequency of HLA-DRB 04 (p = 0.049) among JIA patients was present in comparison to the controls (OR = 2.81, CI:1.02–7.75), other risky alleles were HLA-DRB 10, 13 and 15. However, HLA-DRB 01, 03, 07, 11 and 14 were found to be protective. HLA-DRB 01, 04, 10 and 13 were found to be risky alleles in PPD. However, HLA 03, 07, 11 and 15 were found to be protective alleles among PPD patients. Conclusion: HLA-DRB 04 was found in a higher frequency in JIA patients with a significant difference in comparison to the controls, denoting that it may play a role in the genetic pathogenesis of JIA. 相似文献
4.
目的 了解贵州省鸡源空肠弯曲菌的分子流行特征,阐明各地菌株间的亲缘关系和进化特征。方法 在贵州省随机抽取7个大型养鸡场,共采集210份鸡的新鲜粪便样本,分离培养出38株空肠弯曲菌,采用多位点序列分型对分离株的序列型及克隆复合体进行构成和聚类分析,与PubMLST数据库中来自国内的分离株分子特征进行比较。结果 贵州省38株鸡源空肠弯曲菌分为23种ST型和8个克隆复合体,其中9种是目前中国大陆地区已有的ST型,2个等位基因和8种序列型为新发现的。ST型构成比前四位分别是ST - 45、ST - 161、ST - 354、ST - 4 324,与数据库中已有的6株贵州来源菌株相比,不存在共同的ST型。优势克隆复合体(CC - 45、CC - 354、CC - 52)与数据库中鸡源分离株的前三位克隆复合体没有重叠。菌株遗传进化树显示,本研究中属于优势克隆复合体的18株菌与国内部分人源、猪源、野生鸟源、鹅源分离株有较近的遗传距离。结论 贵州省鸡源空肠弯曲菌具有高度遗传多样性,在一定程度上表现出地域流行特征。序列型与国内华东地区的分离株有较高的交叉性,部分分离株与国内人、野生鸟、鹅等来源分离株遗传距离近,应加强对不同地区、不同宿主来源空肠弯曲菌的动态监测。 相似文献
5.
【目的】利用高通量测序技术获得大青的转录组信息特征。【方法】通过高通量测序平台Illumina HiSeq;2500对大青进行转录组测序,采用Trinity软件de novo组装获得Unigene,并基于序列同源性对Unigene进行功能注释,得到大青转录组的遗传信息。【结果】测序数据经过质控后共获得26 394 223个高质量的Reads,通过de novo组装获得100 191个Unigene,N50长度为1 055 bp,平均长度724.4 bp。其中59 690个(59.58%)Unigene在NR、SwissProt、KOG、GO、KEGG数据库中均得到注释。其中KEGG数据库注释到38 260个Unigene,涉及136条代谢通路。在大青转录组中共鉴定到407个Unigene参与萜类化合物的生物合成,165个Unigene涉及类黄酮生物合成,29个Unigene参与黄酮和黄酮醇生物合成,37个Unigene参与异黄酮生物合成,同时,还鉴定到210类转录因子。MISA分析发现6 680个Unigene包含8 640个简单重复序列。【结论】利用高通量测序技术和生物信息分析获得了大青的转录组信息特征,这些数据可为后期开展功能基因鉴定、解析黄酮类化合物次生代谢途径及其调控机制奠定研究基础。 相似文献
6.
《Taiwanese journal of obstetrics & gynecology》2022,61(1):129-131
ObjectiveWith this case report, we would like to highlight the importance of a multidisciplinary approach and atypical findings of congenital high airway obstruction sequence (CHAOS), anhydramnios, and renal dysgenesis in the prenatal diagnosis of Fraser syndrome (FS).Case reportA 25-year-old primigravida at 19 weeks of routine anomaly scan revealed abnormal sonographic findings such as fetal bilateral dysplastic small kidneys and gross oligohydramnios. The further detailed evaluation revealed that both fetal lungs were hyperechogenic with prominent (dilated) trachea and bronchi suggestive of CHAOS. Based on these findings, a diagnosis of FS was suspected. The couple was counseled and the pregnancy was terminated. The postmortem evaluation and novel homozygous variant in the FRAS1 gene confirmed the diagnosis of FS.ConclusionThe diagnosis and counseling of the patient were supported by a well-coordinated, multidisciplinary approach involving an obstetrician, a fetal medicine specialist, a medical geneticist, and a fetal pathologist. 相似文献
7.
Twin reverse arterial perfusion (TRAP) sequence is a severe anomaly in monochorionic twins where one twin has profound corporeal underdevelopment and acardia. The normal “pump” co-twin provides blood flow to the acardiac twin through placental anastomoses which may lead to cardiac failure and pump twin demise as well as preterm delivery from severe polyhydramnios. Treatments include radiofrequency ablation, bipolar cord coagulation, and intrafetal laser with each aimed at occluding blood flow to the acardiac twin. However, none of these modalities has proven superior in terms of either pump twin survival or minimization of complications, including preterm premature rupture of membranes, preterm birth, or unexpected co-twin demise. The optimal timing of treatment is also unknown, without clear indications for intervention versus expectant management. Very early treatment of TRAP (i.e., <16 weeks) has been proposed to reduce first-trimester demise; however, this approach remains experimental. Further investigation is required to determine the best treatment and timing of intervention for TRAP. 相似文献
8.
9.
Twin anemia polycythemia sequence (TAPS) is a consequence of unequal sharing of red blood cells between monochorionic twins resulting in anemia in the donor and polycythemia in the recipient twin. Prenatally TAPS can occur spontaneously or complicate incomplete laser surgery for twin transfusion syndrome. While there may be clinical overlap with twin transfusion syndrome or selective fetal growth restriction, diagnosis relies on Doppler measurement of middle cerebral artery peak systolic velocities. Significantly discordant velocities are diagnostic, while severity staging is based on signs of cardiovascular compromise. Conservative management, fetoscopic laser coagulation, selective twin reduction, fetal blood and exchange transfusion, and delivery may be selected guided by the gestational age of diagnosis, the severity of the condition, the likelihood of success, and the patients’ priorities. Prenatal curative treatment that minimizes the risk for prematurity and residual morbidity at birth is most likely to offer the greatest short-term and long-term benefits. 相似文献
10.