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121.
The sequences of the 5'-noncoding regions of RNA 4 of seven strains of alfalfa mosaic virus were compared. In each case, the coat protein cistron was preceded by a leader sequence of 39 nucleotides (including the initiator codon). At position 26, an A-, G-, or U-residue was found. Otherwise the leader sequences are identical. 相似文献
122.
目的:研究早期慢性肾病患者的血管内皮功能损害程度及其与肾脏病理损伤的关系。方法:60例研究对象分为3组:A组为20例正常对照组;B组为20例早期慢性肾病患者血压正常组;C组为20例早期慢性肾病患者肾性高血压组。对各组患者应用高频超声检测肱动脉充血前后管径变化率,评价早期慢性肾病患者血管内皮功能损害程度。对病例组行超声引导下穿刺活检,并对肾组织损伤程度行半定量积分,分析血管内皮功能与年龄、血压、肾脏病理损伤的关系。结果:①C组血流介导的血管舒张功能(Flow-mediated dilation,FMD)低于A组和B组(P<0.05),A组与B组之间FMD无差异性(P>0.05);②FMD与收缩压、肾小球损伤积分、肾间质损伤积分有相关性(P<0.05),与年龄、舒张压无相关性(P>0.05)。结论:①肾性高血压患者在肾功能损害之前已经存在血管内皮功能的异常;②血管内皮功能紊乱对肾脏的病理损伤有一定的促进作用;③高频超声早期检测慢性肾病患者的血管内皮功能有重要的临床意义。 相似文献
123.
Van Santen S de Mast Q Luty AJ Wiegerinck ET Van der Ven AJ Swinkels DW 《The American journal of tropical medicine and hygiene》2011,84(1):148-151
In malaria-endemic areas, iron deficiency and placental Plasmodium falciparum infection commonly coexist. In primigravidae and their newborns, hepcidin and other iron parameters were evaluated in groups and classified according to placental P. falciparum and maternal anemia status. Mothers had relatively high hepcidin levels considering their low iron status. In cord blood, levels of hepcidin, hemoglobin, and other iron parameters were also similar for groups. We conclude that maternal hepcidin is not significantly altered as a function of placental infection and/or anemia. Importantly, fetal hemoglobin and iron status were also unaffected, regardless of the presence of placental infection or maternal anemia. 相似文献
124.
Pascal Hannemann Kevin WA Göttgens Bob J van Wely Karel A Kolkman Andries J Werre Martijn Poeze Peter RG Brink 《BMC musculoskeletal disorders》2011,12(1):90
Background
The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%), non-union (5-21%) and early osteo-arthritis (up to 32%) which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences. 相似文献125.
Quirijn de Mast Edmee C. van Dongen-Lases Dorine W. Swinkels An-Emmie Nieman Meta Roestenberg Pierre Druilhe Theo A. Arens Adrian J. Luty Cornelis C. Hermsen Robert W. Sauerwein Andre J. van der Ven 《British journal of haematology》2009,145(5):657-664
The correct selection of individuals who will benefit from iron supplements in malaria-endemic regions requires improved insight in the effects of malaria on host iron homeostasis and innovative biomarkers. We assessed sequential changes in serum hepcidin and in traditional biochemical iron status indicators during an experimental Plasmodium falciparum malaria infection with five adult volunteers. The haemoglobin content of reticulocytes (Ret-He ) and of mature red blood cells (RBC-He ) represented iron incorporation into haemoglobin. Low-density parasitaemia and its treatment induced a mild increase in interleukin (IL)-6 and serum hepcidin concentrations. Despite this only mild increase, a marked hypoferraemia with a strong increase in serum ferritin concentrations developed, which was associated with a sharp fall in Ret-He , while RBC-He remained unchanged. The ratio of soluble transferrin receptor (sTfR) to log ferritin concentrations decreased to an average nadir of 63% of the baseline value. We concluded that even mild increases in serum hepcidin and IL-6 concentrations result in a disturbed host iron homeostasis. Serum hepcidin, Ret-He and Delta-He (Ret-He minus RBC-He ) are promising biomarkers to select those individuals who will benefit from iron supplements in malaria endemic regions, while the sTfR/log ferritin ratio should be used with caution to assess iron status during malaria. 相似文献
126.
目的:探讨甘氨双唑钠(CMNa)对III期肺癌的放射增敏作用及不良反应。方法:采用随机分组的方法将经病理学确诊的Ⅲ期非小细胞肺癌(NSCLC)患者分为实验组(A组,放疗加甘氨双唑钠)及对照组(B组,单纯放疗)。两组放疗方法均一样。A组在放疗同时,加用CMNa(800mg/m^2),每周3次,至疗程结束;B组为单纯放疗,评价两组疗效及观察不良反应。结果:A组的CR+PR为82.6%(19/23),显著高于B组的52.2%(12/23),P〈0.05,差异有统计学意义。两组的不良反应比较,P〉0.05,差异无统计学意义。结论:甘氨双唑钠对局部晚期非小细胞肺癌有放射增敏作用.可提高有效率(CR+PR),但不增加不良反应。 相似文献
127.
目的:分析两种标准空腹血糖受损人群葡萄糖负荷后血糖代谢特点。方法:对3828名40岁以上居民进行流行病学调查,对空腹血糖≥5.6mmol/L者行75g葡萄糖负荷试验,据不同空腹血糖受损诊断标准分析负荷后2h血糖代谢情况。结果:在以空腹血糖为6.1mmol/L为切点诊断的245例空腹血糖受损(IFG)人群中,糖耐量减低(IGT)的患病率为41.22%,女性(25.71%)高于男性(15.51%);2型糖尿病(T2DM)患病率为20.82%,女性(11.84%)高于男性(8.98%)。在以空腹血糖为5.6mmol/L为切点诊断的627例空腹血糖受损人群中,糖耐量减低的患病率为37.00%,女性(23.76%)高于男性(13.23%);2型糖尿病患病率为13.88%,女性(9.52%)高于男性(4.63%)。结论:以空腹血糖为5.6mmol/L和6.1mmol/L为切点诊断的空腹血糖受损人群葡萄糖负荷后2h血糖代谢异常率分别为50.88%和62.04%,患病率女性均高于男性。 相似文献
128.
Smulders YM Smith DE Kok RM Teerlink T Swinkels DW Stehouwer CD Jakobs C 《British journal of haematology》2006,132(5):623-629
Haematological sequellae of vitamin B12 deficiency are attributed to disturbed DNA synthesis, but vitamin B12 itself plays no role in DNA biosynthesis. A proposed explanation for this is the methylfolate trap hypothesis. This hypothesis states that B12 deficiency impairs overall folate metabolism because 5-methyltetrahydrofolate (5MTHF) becomes metabolically trapped. This trap results from the fact that 5MTHF can neither be metabolised via the methionine synthase pathway, nor can it be reconverted to its precursor, methylenetetrahydrofolate. Other manifestations of the methylfolate trap include cellular folate loss because of shorter 5MTHF polyglutamate chains and global hypomethylation. The methylfolate trap has never been demonstrated in humans. We describe a patient with B12 deficiency who was homozygous for the common methylenetetrahydrofolate reductase (MTHFR) C677T mutation. We analysed red blood cell (RBC) folate vitamers and global DNA methylation by liquid chromatography (LC) in combination with tandem mass spectrometry, and 5MTHF polyglutamate length by LC-electrochemical detection. Compared to post-B12 supplementation values, homocysteine was higher (52.9 micromol/l vs. 16.8 micromol/l), RBC folate was lower (268.92 nmol/l vs. 501.2 nmol/l), the 5MTHF fraction of RBC folate was much higher (94.5% vs. 67.4%), polyglutamate chain length was shorter (more tetra- and pentaglutamates), and global DNA methylation was 22% lower. This is the first time that virtually all features of the methylfolate trap hypothesis have been demonstrated in a human with vitamin B12 deficiency. 相似文献
129.
目的:探讨泌尿生殖道支原体感染及耐药情况,为临床治疗提供合理、科学的抗生素用药依据.方法:应用支原体培养鉴定药敏试剂盒检测从患者中分离培养的支原体对10种抗生素的药敏情况,并对结果进行分析.结果:2 137例患者中1 163例支原体阳性,阳性率为54.42%;其中女性标本中阳性率为59.58%、男性标本中阳性率为38.78%,女性感染率明显高于男性,Uu、Mh、Uu+Mh阳性率分别为41.18%(880/2137)、3.88%(83/2137)、9.36%(200/2137),以Uu感染率最高,对Uu敏感率最高的抗生素为强力霉素,耐药率最高者为环丙沙星.结论:泌尿生殖道支原体的感染相当普遍,以Uu阳性率最高,女性高于男性,其耐药性已相当严重,应引起临床重视. 相似文献
130.
Swinkels ME Simons A Smeets DF Vissers LE Veltman JA Pfundt R de Vries BB Faas BH Schrander-Stumpel CT McCann E Sweeney E May P Draaisma JM Knoers NV van Kessel AG van Ravenswaaij-Arts CM 《American journal of medical genetics. Part A》2008,(11):1430-1438
The deletion 9p syndrome is caused by a constitutional monosomy of part of the short arm of chromosome 9. It is clinically characterized by dysmorphic facial features (trigonocephaly, midface hypoplasia, and long philtrum), hypotonia and mental retardation. Deletion 9p is known to be heterogeneous and exhibits variable deletion sizes. The critical region for a consensus phenotype has been reported to be located within a approximately 4-6 Mb interval on 9p22. In the present study, deletion breakpoints were determined in 13 Dutch patients by applying fluorescence in situ hybridization (FISH) and in some specific cases by array-based comparative genomic hybridization (array CGH). No clear genotype-phenotype correlation could be established for various developmental features. However, we were able to narrow down the critical region for deletion 9p syndrome to approximately 300 kb. A functional candidate gene for trigonocephaly, the CER1 gene, appeared to be located just outside this region. Sequence analysis of this gene in nine additional patients with isolated trigonocephaly did not reveal any pathogenic mutations. 相似文献