首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5749篇
  免费   355篇
  国内免费   74篇
耳鼻咽喉   59篇
儿科学   1904篇
妇产科学   839篇
基础医学   241篇
口腔科学   36篇
临床医学   530篇
内科学   195篇
皮肤病学   15篇
神经病学   287篇
特种医学   125篇
外科学   215篇
综合类   585篇
预防医学   717篇
眼科学   38篇
药学   338篇
  2篇
中国医学   33篇
肿瘤学   19篇
  2023年   110篇
  2022年   176篇
  2021年   197篇
  2020年   209篇
  2019年   218篇
  2018年   246篇
  2017年   251篇
  2016年   227篇
  2015年   220篇
  2014年   471篇
  2013年   475篇
  2012年   367篇
  2011年   362篇
  2010年   313篇
  2009年   331篇
  2008年   260篇
  2007年   276篇
  2006年   272篇
  2005年   212篇
  2004年   157篇
  2003年   95篇
  2002年   81篇
  2001年   71篇
  2000年   53篇
  1999年   52篇
  1998年   32篇
  1997年   33篇
  1996年   44篇
  1995年   30篇
  1994年   34篇
  1993年   27篇
  1992年   22篇
  1991年   14篇
  1990年   31篇
  1989年   19篇
  1988年   20篇
  1987年   9篇
  1986年   13篇
  1985年   15篇
  1984年   15篇
  1983年   10篇
  1982年   17篇
  1981年   14篇
  1980年   13篇
  1979年   9篇
  1978年   9篇
  1977年   7篇
  1976年   7篇
  1974年   5篇
  1968年   4篇
排序方式: 共有6178条查询结果,搜索用时 171 毫秒
1.
2.
Acute myeloid leukaemia (AML) is one of the deadliest haematological malignancies. During pregnancy it is a rare comorbidity and can lead to adverse outcomes, such as death, without adequate treatment. The management of AML during pregnancy remains a challenge. We report the case of a primigravida 34-year-old, with 18 weeks of amenorrhoea, who attended the emergency department presenting with pain and hypertrophy of the oral mucosa, accompanied by intense asthenia. Acute myeloblastic leukaemia was diagnosed. The possibility of terminating the pregnancy was offered given the lack of evidence regarding the maternal-foetal outcome, but the patient rejected it, so chemotherapy treatment was started. In the ultrasound controls there was no evidence of teratogenic alterations nor foetal growth restriction, and there were no alterations in Doppler flow values. It was decided to end the pregnancy at 32 + 3 GW. A preterm male was born through eutocic delivery with a normal Apgar test and umbilical cord pH, and did not require resuscitation. The puerperium was favourable and 15 days following discharge she was admitted for a bone marrow transplant from her HLA identical sister. The patient died due to rejection of the transplant and the complications derived from this event.  相似文献   
3.
目的 探讨玻璃体腔内注射抗血管内皮生长因子(vascular endothelial growth factor,VEGF)治疗早产儿视网膜病(retinopathy of prematurity,ROP)的效果及复发的危险因素。 方法 回顾性收集2016年1月—2021年12月在郑州大学第一附属医院出生行抗VEGF治疗的ROP患儿159例的临床资料,根据首次抗VEGF治疗后随访周期内ROP复发与否分为复发组(24例)和非复发组(135例),比较分析2组临床资料,采用多因素logistic回归分析探讨抗VEGF治疗ROP复发的危险因素。 结果 经单次抗VEGF治疗后,所有159例患儿均显示附加病变消退。24例(15.1%)抗VEGF治疗后复发,复发平均时间为治疗后(8.4±2.6)周。多因素logistic回归分析显示,术前眼底出血、总用氧时间较长是ROP复发的危险因素(P<0.05),而妊娠高血压是保护因素(P<0.05)。 结论 玻璃体腔内注射抗VEGF治疗ROP是有效的。术前眼底出血和氧疗时间较长可增加ROP复发的风险,而对于妊娠高血压对ROP复发的影响,还需进一步研究证实。  相似文献   
4.
ObjectiveThis study aimed to clarify the effectiveness of cervical cerclage in preventing recurrent preterm births.Materials and methodsA retrospective study was conducted using the perinatal registration database of the Japan Society of Obstetrics and Gynecology for the Perinatal Center from 2014 to 2016. The efficacies of history-indicated, ultrasound-indicated, and physical examination-indicated cerclage as preventive treatments for women with a history of preterm birth were evaluated by comparing cerclage and non-cerclage cases. Fisher's exact test was performed to evaluate any significant differences in patient backgrounds. Prior to the evaluation, propensity score matching was performed for history-indicated and ultrasound-indicated cerclage patients.ResultsFor this study, 6060 multiparous women with a history of preterm birth were reviewed. After excluding 17 patients with unknown indications for cervical cerclage, 6043 patients were included in the study. History-indicated and ultrasound-indicated cerclage did not reduce the risk of preterm birth in subsequent pregnancies for any of the pregnancy periods (p = 0.413, p = 1.000). In contrast, physical examination-indicated cerclage significantly reduced the risk of subsequent preterm births for all pregnancy periods (p < 0.001).ConclusionSubsequent preterm births were effectively prevented only in physical examination-indicated cerclage cases. For history- or ultrasound-indicated cerclage, statistically significant differences in subsequent preterm births were not evident.  相似文献   
5.
ObjectiveThe objective of this feasibility study was to examine the implementation and usefulness of an intervention for extremely premature infant (EPI) caregivers.ResultsOne caregiver and five nurses provided feedback with a mean score of 4.4 out of 5 pertaining to helpfulness.ConclusionsImplementation of the Caregiver's Guide was feasible and was positively received by NICU nurses and caregivers. We recommend implementing a revised version of this tool based on nurse and caregiver feedback. The delivery of education should be divided between dayshift and nightshift nurses so that one nurse is not responsible for providing all the information. The education should be categorized by gestational age and day of life and only given when it is pertinent to the care of the child. A section should be added to include a quick reference guide for the medical jargon used in the NICU.  相似文献   
6.
7.
BackgroundPain assessment is essential for the administration of appropriate analgesia. Currently, clinicians use surrogate methods, such as heart rate or behavioural pain scales, to estimate pain in neonates and infants. The Newborn and Infant Parasympathetic Evaluation (NIPE™) monitor aims to provide an objective numeric value (NIPE index) of pain through a continuous assessment of the patient's parasympathetic activity. The aim of this study was to determine if the intraoperative NIPE index monitoring could predict postoperative pain in neonates and infants.MethodsThis prospective observational pilot study included neonates and infants undergoing elective day-surgical procedures (n = 50). Intraoperatively, NIPE indices at 0 (NIPE0), 10 (NIPE10), 20 (NIPE20), 30 (NIPE30) minutes and at completion of surgery (NIPEe), were recorded; the median NIPE index (NIPEm) was calculated for the entire procedure. Postoperative Face, Legs, Activity, Cry, Consolability (FLACC) scale scores were calculated by the nursing staff blinded to the intraoperative NIPE indices.ResultsLinear regression documented an association between the NIPEm and postoperative FLACC score at 0 (r = 0.31, p = 0.03) and 10 min (r = 0.36, p = 0.01). No significant associations were observed for FLACC scores at 20 (r = 0.21, p = 0.2) and 30 min (r = 0.36, p > 0.9). Multiple regression analysis revealed that intraoperative NIPE10, NIPE20, NIPE30 and NIPEe also predicted the FLACC score at 0 min (p = 0.003).ConclusionThe intraoperative NIPE index is predictive of pain in the immediate postoperative period. This association was lost at 20 min likely due to nursing intervention to administer analgesia. NIPE monitoring could be useful in facilitating postoperative pain management in infants.Level of evidenceII.Type of studyStudy of Diagnostic Test.  相似文献   
8.
The transition from fetal to newborn life involves a complex series of physiological events that commences with lung aeration, which is thought to involve 3 mechanisms. Two mechanisms occur during labour, Na+ reabsorption and fetal postural changes, and one occurs after birth due to pressure gradients generated by inspiration. However, only one of these mechanisms, fetal postural changes, involves the loss of liquid from the respiratory system. Both other mechanisms involve liquid being reabsorbed from the airways into lung tissue. While this stimulates an increase in pulmonary blood flow (PBF), in large quantities this liquid can adversely affect postnatal respiratory function. The increase in PBF (i) facilitates the onset of pulmonary gas exchange and (ii) allows pulmonary venous return to take over the role of providing preload for the left ventricle, a role played by umbilical venous return during fetal life. Thus, aerating the lung and increasing PBF before umbilical cord clamping (known as physiological based cord clamping), can avoid the loss of preload and reduction in cardiac output that normally accompanies immediate cord clamping.  相似文献   
9.
《Brain & development》2019,41(8):671-677
ObjectiveWe sought to develop and validate a novel scoring system for the prediction of severe intraventricular hemorrhage (SIVH) in very low birth weight infants (VLBWI).MethodsThis retrospective cohort multicenter study included 615 VLBWI born between 24 and 32 weeks gestational age (GA). Multivariable logistic regression analyses were used to determine which factors evaluated within the first 5 days of life were associated with SIVH and the weights of these variables. The accuracy of the predictive scoring system was prospectively tested in the same units.ResultsThe final SIVH scoring system included the following variables: antenatal steroid therapy, GA, birth weight (BW), 1-min Apgar score, mechanical ventilation and hypotension. The SIVH scores used to divide the subjects into three tiers (low-risk (<5), moderate-risk (5–8) and high-risk (>8)) were developed based on these variables. Of infants with a score below 5, 1.2% (4/339) developed SIVH. Of those with a score above 8, 42.5% (17/40) developed SIVH. The scores were successfully verified in 99 VLBWI.ConclusionsThese findings suggest that among infants with a score >8, the incidence of SIVH is significantly higher. This scoring system can be used to predict the incidence of SIVH during the first 5 days after birth and may contribute to the early intervention in and prevention of SIVH.  相似文献   
10.
《Clinical neurophysiology》2019,130(10):1859-1868
ObjectivePreterm infants are at risk for altered brain maturation resulting in neurodevelopmental impairments. Topographical analysis of high-density electroencephalogram during sleep matches underlying brain maturation. Using such an EEG mapping approach could identify preterm infants at risk early in life.Methods20 preterm (gestational age < 32 weeks) and 20 term-born infants (gestational age > 37 weeks) were recorded by 18-channel daytime sleep-EEG at term age (GA 40 weeks for preterm and 2–3 days after birth for term infants) and 3 months (corrected age for preterm infants).ResultsPreterm infant’s power spectrum at term age is immature, leveling off with term infants at 3 months of age. Topographical distribution of maximal power density however, reveals qualitative differences between the groups until 3 months of age. Preterm infants exhibit more temporal than central activation at term age and more occipital than central activation at 3 months of age. Moreover, being less mature at term age predicts being less mature at 3 months of age.ConclusionTopographical analysis of sleep EEG reveals changes in brain maturation between term and preterm infants early in life.SignificanceIn future, automated analysis tools using topographical power distribution could help identify preterm infants at risk early in life.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号