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111.
妊娠肝内胆汁淤积症患者胎儿缺氧的影响因素 总被引:42,自引:2,他引:42
目的 探讨妊娠肝内胆汁淤积症 (ICP)患者胎儿缺氧机理及其相关因素。方法 分别测定ICP患者 (30例 ,ICP组 )及正常妊娠妇女 (30例 ,对照组 )新生儿脐动脉血胆汁酸总量 (TBA)、次黄嘌呤 (HX)、内皮素 (ET)及有核红细胞 (NRBC)计数。结果 (1)ICP组缺氧者 (10例 )脐血HX水平为(18.6 8± 15 .73) μmol/L ,明显高于ICP组无缺氧者 (2 0例 ) [(6 .87± 2 .82 ) μmol/L ]及对照组 [(6 .81±2 .83) μmol/L](P <0 .0 1) ;但NRBC[(4 .2 0± 2 .49)个 / 10 0白细胞 ,(3.40± 2 .2 6 )个 / 10 0白细胞 ,(3.5 0± 1.74)个 / 10 0白细胞 ]及ET水平 [(72 .44± 12 .2 3)ng/L ,(70 .16± 2 6 .6 1)ng/L ,(6 7.2 7± 43.5 6 )ng/L],各组相似 (P >0 .0 5 )。 (2 )ICP组缺氧者脐血TBA为 (2 3.77± 11.82 ) μmol/L ,明显高于ICP组无缺氧者 (14.86± 5 .46 ) μmol/L ,ICP组无缺氧者脐血TBA又高于对照组 [(9.2 8± 4.39) μmol/L](P <0 .0 1) ;且ICP组脐血TBA与HX水平呈正相关 (r=0 .6 89,P <0 .0 1) ;ICP组羊水胎粪污染率明显高于对照组 (5 3.3% ,13.3% ;P <0 .0 1) ,ICP组羊水胎粪污染者脐血TBA[(2 1.44± 9.92 ) μmol/L],明显高于羊水清亮者 [(13.6 9± 5 .74) μmol/L],差异有显著性 (P <0 .0 5 )。 结论 ICP时 , 相似文献
112.
目的:用无创血流动力学监测系统研究双胎妊娠孕妇的血流动力学特点,及其与妊娠并发症的关系。方法:选择双胎妊娠孕妇118例,分为双胎有并发症组(95例)和双胎无并发症组(23例),另选择同期正常单胎妊娠孕妇(90例)为对照(正常单胎妊娠组)。用无创血流动力学监测系统检测并比较3组孕妇的血流动力学参数:心率(HR)、平均动脉压(MAP)、心脏指数(CI)、心输出量(CO)、周围血管阻力指数(SVRI)和周围血管阻力(SVR)。结果:双胎无并发症组与正常单胎妊娠组比较,HR、CI、CO轻度增高,MAP、SVRI、SVR轻度降低,但差异均无统计学意义(P>0.05)。双胎有并发症组与另两组比较,CI、CO明显降低(P<0.05),MAP、SVRI、SVR明显升高(P<0.05)。结论:双胎妊娠孕妇发生妊娠期高血压、子痫前期、胎儿生长受限与孕妇心排出量降低、外周阻力升高有关。 相似文献
113.
超声测量胎儿腹围预测新生儿出生体重的研究 总被引:15,自引:0,他引:15
目的探讨超声测量胎儿腹围在预测新生儿出生体重和诊断巨大儿中的价值。方法在孕妇分娩前1周超声测量胎儿腹围,追踪胎儿的出生体重,分析胎儿腹围与出生体重的关系。结果(1)共检测1475例单胎孕妇胎儿,胎儿腹围与出生体重呈直线正相关关系,r为0.85(P<0.01)。(2)胎儿腹围<34cm者中无一例巨大儿;胎儿腹围<35cm有1007例,99.7%的新生儿平均出生体重<4000g;胎儿腹围在35~35.9cm有206例,新生儿平均出生体重为(3691±277)g,其中14.6%(30例)的新生儿出生体重≥4000g;胎儿腹围在36~36.9cm有149例,其中51.0%(76例)的新生儿出生体重≥4000g,新生儿平均出生体重为(3957±256)g;胎儿腹围在37~37.9cm有64例,其中84.4%(54例)的新生儿出生体重≥4000g,平均出生体重(4205±250)g;胎儿腹围≥38cm有44例,新生儿平均出生体重≥4000g者为100%(44例),平均出生体重为(4489±267)g。(3)1475例中有811例孕妇行剖宫产术(55.0%),新生儿出生体重为4000~4500g者,剖宫产率为71.4%(125/175),出生体重≥4500g者,剖宫产率为93.8%(30/32),均显著高于新生儿出生体重<4000g的剖宫产率(P<0.01)。结论超声测量胎儿腹围可以预测新生儿出生体重。胎儿腹围与胎儿体重呈高度直线正相关。胎儿腹围<35cm提示发生巨大儿的可能性极低;≥37cm提示巨大儿的可能性大。 相似文献
114.
115.
皮质醇是妊娠期母体代谢与胎儿发育代谢不可缺少的物质。母体内与胎体内的皮质醇浓度梯度提示,胎盘是阻止母体皮质醇到达胎儿的屏障,11β-羟基类固醇脱氢酶(11β—HSD)在这个屏障中起主导作用。在妊娠不同阶段,皮质醇代谢与调节存在差异。母体的皮质醇能在妊娠中晚期通过胎盘。多种因素会影响11β—HSD的活性,进而影响皮质醇在母体与胎儿问的代谢调节。 相似文献
116.
Endothelium-derived nitric oxide (NO) plays a key role in the regulation of vascular tone in health and disease. The present study addresses the contribution of NO to the baseline vascular tone in the fetal placental circulation of type 1 diabetic women. To this end, we performed ex-vivo dual perfusions of isolated cotyledons from seven women with type 1 diabetes mellitus and 24 healthy women. The fetal arterial pressure was considered to be a measure of fetal vascular resistance. The contribution of NO to the baseline vascular tone of the fetal placental circulation was quantified by addition of the NO-synthase inhibitor N(G)-nitro-arginine-methylester (L-NAME). Apart from the diabetic state, we studied the influence of exogenous insulin on the response to L-NAME. Mean (+/-SEM) baseline fetal arterial pressure was higher in diabetes (25.7+/-3.4 mm Hg vs 18.0+/-1.7 mm Hg, P<0.05). Maximum perfusion pressure after L-NAME was 87.9+/-7.1 mm Hg in diabetes vs 58.9+/-4.5 mm Hg in controls (P<0.01). The net L-NAME-induced increase in fetal arterial pressure was higher in diabetes (62.2+/-9.1 mm Hg vs 40.9+/-3.5 mm Hg, P<0.05). Although insulin induced a shift to the left of the L-NAME-curve, the net L-NAME-induced increase in fetal arterial pressure was not affected. We conclude that diabetes is associated with an increased baseline vascular tone of the fetal placental vascular bed. This can not be explained by attenuated NO-mediated effects. In contrast, the activity of the NO-pathway seems to be increased in diabetes. The latter observation seems not to be caused by high insulin levels. 相似文献
117.
118.
冻融胚胎移植(frozen-thawed embryo transfer,FET)技术因具有提高累积妊娠率和降低卵巢过度刺激风险等优点被广泛应用于临床,移植胚胎质量、子宫内膜以及两者同步性是FET成功的关键因素。临床常见的子宫内膜准备方案包括自然周期、控制性卵巢刺激周期、激素替代治疗(hormone replacement treatment,HRT)周期以及降调节HRT周期。大多数妇女采用常规方案进行FET子宫内膜准备,但多囊卵巢综合征、子宫内膜异位症、子宫腺肌病、反复着床失败以及薄型子宫内膜等特殊人群,采用常规方案临床效果欠佳。垂体降调节方法是在促性腺激素释放激素激动剂(gonadotropin-releasing hormone agonist,GnRHa)垂体降调节基础上应用HRT准备子宫内膜,即降调节HRT周期较常规方案可有效改善上述特殊人群的妊娠结局。综述GnRHa降调节HRT周期的相关机制及其适宜人群。 相似文献
119.
Garry Kerch 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(1):13-25
The direct and indirect (by changing mechanical properties) effects of hydration at interfaces on cellular processes and tissue diseases are reviewed. The essential effect of substrate stiffness on cellular processes was demonstrated in the last decade. The combined effect of surface stiffness and hydration at interfaces has garnered much less attention, though hydration and dehydration play important roles in biological processes. This review focuses on the studies that demonstrate how hydration affects biological processes at interfaces. Elevated sodium and dehydration stimulate inflammatory signaling in endothelial cells and promote atherosclerosis. Various types of implant and blood contacting device coatings with varied surface stiffness and hydration have been reported. Effect of hydration on polymer modulus of elasticity and viscoelasticity was discussed taking into account cells adhesion, migration, proliferation, differentiation on surfaces with various degree of hydration. Future directions of research were considered, including the use of nanotechnology to regulate the hydration degree. 相似文献
120.
Fenella J. Kirkham Dimitrios Zafeiriou David Howe Philippa Czarpran Ashley Harris Roxanna Gunny Brigitte Vollmer 《European journal of paediatric neurology》2018,22(6):989-1005
Fetal stroke is an important cause of cerebral palsy but is difficult to diagnose unless imaging is undertaken in pregnancies at risk because of known maternal or fetal disorders. Fetal ultrasound or magnetic resonance imaging may show haemorrhage or ischaemic lesions including multicystic encephalomalacia and focal porencephaly. Serial imaging has shown the development of malformations including schizencephaly and polymicrogyra after ischaemic and haemorrhagic stroke. Recognised causes of haemorrhagic fetal stroke include alloimmune and autoimmune thrombocytopaenia, maternal and fetal clotting disorders and trauma but these are relatively rare. It is likely that a significant proportion of periventricular and intraventricular haemorrhages are of venous origin. Recent evidence highlights the importance of arterial endothelial dysfunction, rather than thrombocytopaenia, in the intraparenchymal haemorrhage of alloimmune thrombocytopaenia. In the context of placental anastomoses, monochorionic diamniotic twins are at risk of twin twin transfusion syndrome (TTTS), or partial forms including Twin Oligohydramnios Polyhydramnios Sequence (TOPS), differences in estimated weight (selective Intrauterine growth Retardation; sIUGR), or in fetal haemoglobin (Twin Anaemia Polycythaemia Sequence; TAPS). There is a very wide range of ischaemic and haemorrhagic injury in a focal as well as a global distribution. Acute twin twin transfusion may account for intraventricular haemorrhage in recipients and periventricular leukomalacia in donors but there are additional risk factors for focal embolism and cerebrovascular disease. The recipient has circulatory overload, with effects on systemic and pulmonary circulations which probably lead to systemic and pulmonary hypertension and even right ventricular outflow tract obstruction as well as the polycythaemia which is a risk factor for thrombosis and vasculopathy. The donor is hypovolaemic and has a reticulocytosis in response to the anaemia while maternal hypertension and diabetes may influence stroke risk. Understanding of the mechanisms, including the role of vasculopathy, in well studied conditions such as alloimmune thrombocytopaenia and monochorionic diamniotic twinning may lead to reduction of the burden of antenatally sustained cerebral palsy. 相似文献