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81.
用标准微电极技术观察了中药蝙蝠葛的有效成分蝙蝠葛碱对奎尼丁诱发的豚鼠乳头肌早后去极化及触发活动的影响. 结果表明,奎尼丁2 μmol·L-1能诱发豚鼠乳头肌早后去极化及触发活动,早后去极化的发生率为8/20, 幅值为13.4±2.6 mV, 起始电位为-42±5 mV, 触发活动的发生率为2/20. 蝙蝠葛碱20 μmol·L-1能明显抑制奎尼丁诱发的早后去极化及触发活动,早后去极化的发生率为4/20,幅值为7.3±1.1 mV,无触发活动. 结果提示蝙蝠葛碱具有抗早后去极化所致心律失常.  相似文献   
82.
This study investigated the temporal evolution in the discrimination of the newborn's crying by the mother, from the first to the eighth day after birth. The sample included twenty human mothers who had had an uneventful pregnancy, labour and delivery. They were asked to identify the spontaneous cries of their newborn babies from tape-recorded cries containing cries from their own newborn and from three other newborns. On the first day, the percentage of correct answers was 48#pc, then 81 #pc on the eighth day. Two acoustic features that may underlie this discrimination were analyzed: the maximum Fo values and the average number of cry bursts per second. On the seventh day, these two acoustic variables and the discrimination abilities significantly correlate.  相似文献   
83.
目的观察人类重组红细胞生成素(r-HuEPO)对透析前贫血的疗效,探讨早期治疗肾性贫血的意义.方法患者分两组,治疗组应用r-HuEPO皮下注射,补充叶酸、铁剂,给予饮食疗法、大黄散、控制血压等措施.对照组不用r-HuEPO治疗,其它措施相同.观察症状、HGB、HCT、SCr和血清钾、钠、氯水平.结果治疗组症状改善,生活质量提高;HGB、HCT明显升高,与对照组比较有显著性差异(P<0.01).血清肌酐无明显升高.结论r-HuEPO能明显提高HGB、HCT水平,安全有效治疗透析前贫血,肾性贫血早期治疗值得重视和进一步探讨.  相似文献   
84.
中国2000~2001年流行性感冒流行概况   总被引:24,自引:2,他引:22  
目的:了解中国2000-2001年流行性感冒(流感)流行及抗原性变异情况。方法:鸡胚传代病毒用于抗原分析;病毒液提取RNA进行逆转录-聚合酶链反应(RT-CR),扩增产物纯化后测序。然后用MegAlign(Version1.03)和Editseq(Version3.69)软件进行基因种系发生树分析。结果:2001年流行的H1N1亚型病毒血凝素蛋白重链(H1N1)相比,在抗原决定簇D区的190位发生了氨基酸替换;基因种系发生树表明2001年的H1N1亚型流感病毒存在基因特性不同的两系病病毒株,国内人群中仍然同时流行着两种抗原性明显不同的B型流感病毒(Yamagata系和Victoria系),Yamagata系病毒占大多数,Version系的HA1区基因与B/山东/7/97毒株相比,其197和199位氨基酸发生了替换。B型的基因种系发生树也证实Version系病毒株的抗原性改变。2000年分离的H3N2亚型流感病毒的HA1区氨基酸序列与A/悉尼/5/97(H3N2)间有7-8个氨基酸的差异;2001年分离的H3N2病毒株与2000年的病毒株相比,又有83、186、202、222位发生了氨基酸替换,表明H3N2亚型病毒株间的抗原性发生了较明显的变异。结论:2000-2001年中国流感的流行情况较为平静;H3N2亚型的抗原性发生了变异,H1N1亚型和B型病毒的抗原性虽没有发生明显的变异,但它们均同时流行着两系抗原性不同的毒株。  相似文献   
85.
目的:调查潮汕地区健康青年中H9、H6、H5三种甲型流感病毒亚型的隐性感染情况,以期了解上述三种禽类甲型流感病毒亚型是否能够或已经从禽类直接或间接传染给人。方法:潮汕地区健康青年血清946份,通过HI实验进行抗体检测。结果:H9亚型抗体阳性率达37.2%;同时发现有三份血清存在H5抗体;未见H6亚型抗体的存在。结论:H9亚型在健康青年中的隐性感染率非常高;H5亚型抗体的存在也应值得注意。  相似文献   
86.
The Effects of Na~+/Ca~(2+) exchange (NCX) on the Repolarization of Canine Ventricular Myocyte-Potential Arrhythmogenic Effect of NCX during a Mis-matched Repolarization and Relaxation Xiamen Zhongshan Hospital, Xiamen Medical College, Xiamen University@巩燕$Visiting scholar of cardiac arrhythmia research institute,university hospital of Oklahoma!U.S.A @王焱 @BELA Szabo$Basic cardiac research laboratory,cardiac arrhythmia research institute,university hospital of Oklahoma!…  相似文献   
87.
Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D1 & D3) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re‐treatment) during the 3‐year period. The data was derived from a prospective 3‐year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D1 threshold in 12‐year‐olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D3 threshold in 12‐year‐olds (Az = 0.670). Assessing caries visually at either the D1 or the D3 threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3‐year period (Az for D1 = 0.507; Az for D3 = 0.518).  相似文献   
88.
Early Intervention for Trauma: Current Status and Future Directions   总被引:5,自引:0,他引:5  
Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma.  相似文献   
89.
The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25 of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression. Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis (68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results.  相似文献   
90.
Cognitive models of depression propose that negative schemas contribute to depressive symptoms. Early experiences, particularly parenting, have been proposed to influence cognitive schemas and have also been shown to correlate with depression. This study explores the concurrent relationship between retrospective reports of parenting, Early Maladaptive Schemas (EMSs) described by J. E. Young (1994), and symptoms of depression in a sample of undergraduate students (N = 194). The EMSs of defectiveness/shame, insufficient self-control, vulnerability, and incompetence/inferiority were associated with perceptions of parenting and depressive symptomatology. There was evidence that these four EMSs partially mediate the relationship between parental perceptions and depressive symptomatology. Results are discussed in relation to previous findings, theory, and the measurement of EMSs.  相似文献   
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