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91.
血清亚硝酸盐的快速测定 总被引:1,自引:1,他引:0
目的:建立一种无需去蛋白的血清亚硝酸盐的快速测定方法。方法:加入蛋白活化剂后,直接用Gries试剂显色分光光度测定。结果:方法的检测下限为0.2μmol/L,相对标准差为5.13%~8.86%,回收率为94.5%~99.8%(平均为97.8%)。血清NO-2浓度为14.38±0.25μmol/L时,批内变异系数为1.75%,NO-2浓度为5.69±0.25μmol/L时,批间变异系数为4.46%。测定55例正常人血清,得到血清中NO-2浓度的平均值分别为5.36±2.16umol/L;对糖尿病病人血清测定结果表明,亚硝酸盐浓度明显高于正常人。与去蛋白的Gries试剂分光光度法比较,结果无统计学差异。结论:用蛋白活化剂替代蛋白沉淀剂,减少操作步骤和干扰,测定准确、简便、快速,适用于血清中NO-2的测定。 相似文献
92.
急性有机磷中毒患者的血钾变化及临床意义的探讨 总被引:1,自引:0,他引:1
目的:探讨急性有机磷中毒患的血清钾变化及其临床意义。方法:对68例发病6小时内的急性有机磷中毒的患入院后测定血清钾,并根据不同的中毒程度、中毒方式、发病时间分组在比较,并设正常对照组对照。结果:中毒各组均有明显的低钾血症,与对照组比较均有显性意义(P<0.01),且重度中毒组与中、轻度组比较亦有显性意义(P>0.05),但两种不同的中毒途径与不同的中毒时间的组间血清钾的比较无显性意义(P>0.05)。结论:急性有机磷中毒可致明显的低钾血症,中毒越重,低钾血症越明显。在发病早期应注意监测血清钾的变化,及时纠正低血钾,预防或减轻中毒后严重合并症的产生。 相似文献
93.
常见阴离子对血清氯离子选择性电极法测定的影响 总被引:1,自引:0,他引:1
目的:研究离子选择性电极在测定血清氯时的影响因素。方法:用E-555电解质分析仪测定氟化钠、溴化钠、碳酸氢钠、硫氰化钾、碘化钾、铁氰化钾、硫化钠以及叠氮钠溶液,并将溴化钠、硫氰化钾、碘化钾、铁氰化钾、硫化钠、叠氮钠分别加入Cl~-均值为100mmol/L的混合血清中观察其具体的干扰情况。结果:所测8种物质中氟化钠、碳酸氢钠的影响较小,而溴化钠、铁氰化钾、碘化钾、铁氰化钾、硫化钠、叠氮钠的影响较大。结论:溴离子、碘离子、硫离子、氢氰根离子、叠氮钠对离子选择性电极法影响性较大,我们在工作中应加以重视。 相似文献
94.
Special Pharmacokinetic Considerations in Children 总被引:4,自引:2,他引:2
W. Edwin Dodson 《Epilepsia》1987,28(S1):S56-S69
Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection. 相似文献
95.
The pathogenesis of diabetic neuropathy is incompletely understood. The possibility that humoral neurotoxic factors contribute as a cause of diabetic neuropathy was tested by application of serum from patients with Type 1 and Type 2 diabetes to mouse neuroblastoma cells, which have the characteristics of adrenergic neurons in culture. Serum from patients with Type 1 diabetes and somatic neuropathy significantly inhibited both proliferation and differentiation of neuroblastoma cells, while serum from patients with Type 1 diabetes but no symptoms of neuropathy and patients with Type 2 diabetes and neuropathy had no effect on proliferation, and serum from Type 2 patients only marginally inhibited differentiation. The effects of Type 1 diabetic serum could be reversed by pre-absorption of the serum to neuroblastoma cells, and were independent of glucose levels. Immunoglobulins precipitated from the sera mimicked the effects of whole sera. These results suggest that Type 1 diabetes mellitus causes a change in serum composition, possibly related to autoimmunity, that is capable of contributing to adrenergic autonomic neuropathy in diabetic patients. 相似文献
96.
建立了HPLC方法测定人血清中丙戊酸钠的药物浓度。采用反相柱和乙腈-水(60∶40)作为流动相,庚酸作为内标,血样经提取后,用4-溴甲基-6,7-二甲氧基香豆素衍生化,测定波长设在λS325nm和λR398nm,内标庚酸的保留时间为4.57min,丙戊酸钠的保留时间为5.21min,线性范围为2~150μg/ml。测定了10名健康受试者单次口服丙戊酸钠片剂后不同时间的血药浓度。 相似文献
97.
Katrina D. Ramsell Bai-Ge Zhao Daniel Baker Peter Cobbett 《Brain research bulletin》1996,39(2):109-114
The effects of serum on the morphological plasticity exhibited by pituicytes in explant cultures of the neurohypophysis of adult rats have been examined. Cultured pituicytes are normally nonstellate, protoplasmic, amorphous cells (< 25% are stellate with a distinct cell body and phase bright processes). After incubation (90 min) of pituicyte cultures in a HEPES buffered salt solution (HBSS) supplemented with isoproterenol or forskolin, the fraction of stellate pituicytes significantly increased. The increase in the fraction of stellate cells induced by isoproterenol was not reversed by subsequent incubation in isoproterenol-free HBSS for 90 min. In contrast, after stellation was induced in cultures by exposure to forskolin (90 min), the fraction of stellate cells was significantly reduced if these cultures were incubated in forskolin-free, serum (0.5%) supplemented HBSS for the same duration. Serum also blocked the increase in the fraction of stellate pituicytes induced by forskolin. These experiments suggest that serum components may have a significant role in controlling the plasticity of neuroglial relations in the neurohypophysis priviously demonstrated in vivo. 相似文献
98.
冠心病中血糖与血清微量元素间的关系分析 总被引:1,自引:0,他引:1
对75例冠心病患者依血糖水平分两组,进行12种血清微量元素测定,旨在探讨微量元素与冠心病及糖尿病间的相互关系。结果发现锌、铬、锰、硒、钴元素高血糖组较对照组血清水平为低,呈非常显著差异(P<0.0l);铜、镍元素增高,差异显著(P<0.05);而锶、铁、砷、铅、铝元素两组间无显著差异(P>0.1)。表明部分微量元素与冠心病及血糖间存在着密切联系。 相似文献
99.
玉米油和猪油对大鼠血脂血糖代谢和脑脂褐质影响的比较研究 总被引:5,自引:0,他引:5
采用幼年SD雄性大鼠30只,体重150±20g,随机分成三组,每组10只:(1)基础饲料组:普通大鼠饲料;(2)猪油组:基础饲料中加入10%猪油和1.5%胆固醇;(3)玉米油组:在基础饲料中加入10%玉米油和1.5%胆固醇,饲养9周,比较玉米油和猪油对大鼠血脂血糖和脑脂褐质的不同影响。结果表明,玉米油组TC和LDL-C水平较猪油组低,虽然两组均高于基础饲料组。玉米油组的HDL-C比猪油升高不显著,但HDL-C/TC(%)增加,同时LDL-C/HDL-C比值下降。基础饲料组,猪油组和玉米油组的大鼠平均血清TG分别为1.28,1.21和1.45(mmol/L),各组之间的差别不显著。高脂饲料组动物的空腹血糖(SG)较基础饲料组高,但差别无统计学意义。三组不同饲料大鼠的脑脂褐质(LPF)含量测定结果显示:基础饲料组大鼠的LPF平均值12.9U/g蛋白质,而玉米油组和猪油组均明显升高,分别为28.3和28.8U/g蛋白质。在以血脂各项指标为自常量,大脑LPF含量为因变量的相关分析中发现,LPF与TC和LDL-C呈正相关,相关系数分别为0.691和0.547,P<0.01. 相似文献
100.
I. Steiner G. Feir D. Soffer A. B. Pleet O. Abramsky 《Acta neurologica Scandinavica》1988,77(2):152-157
The causes and clinical features of chronic progressive myelopathy (CPM) were evaluated in a retrospective study of 107 patients. A special emphasis was put on those in whom no underlying cause for the myelopathy could be determined. Of 76 such, 39 (51%) had oligoclonal immunoglobulins (Ig) in the CSF and were therefore considered as possible MS, while the remainder, without oligoclonal Ig, were designated "myelopathy of unknown origin" (MUO). Our "possible MS" group was similar clinically to reported series of proven spinal MS, and it seems therefore, that the presence of oligoclonal Ig permits the recognition of a group of patients with myelopathy who might be at a greater risk for MS. Patients with MUO differed from possible MS patients in several clinical characteristics, but most significantly in disease course and levels of functional disability which were more benign in the former. Myelopathy in possible MS patients was also of a primary pyramidal and asymmetrical nature. It is therefore suggested that the segregation of patients with CPM of undetermined origin into 2 separate groups based on the presence or absence of oligoclonal Ig might be of prognostic significance. 相似文献