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《Journal d'obstetrique et gynecologie du Canada》2022,44(8):901-907
ObjectivePregnancies complicated by fetal heart defects often undergo a planned delivery prior to term by either induction of labour or cesarean delivery to ensure optimal availability of neonatal care. We aimed to assess whether such planned deliveries achieve their goal of better perinatal care.MethodsWe conducted a retrospective case-control study of pregnancies complicated by isolated fetal cardiac defects, without other fetal comorbidities, managed at a single fetal medicine unit over a 10-year period. Only pregnancies delivered past 37 weeks gestation were included. Patients undergoing elective delivery for care planning reasons only were compared with patients in whom planned delivery was clinically indicated and patients who laboured spontaneously. Obstetric and perinatal outcomes were recorded.ResultsOf the 180 pregnancies included in the study, 59 (32.8%) were in the elective group, 49 (27.2%), in the indicated group, and 72 (40%), in the spontaneous group. Mean gestational age at delivery was 39.0 ± 1.1 weeks overall and did not differ between the groups. For the elective group, only 35.6% of deliveries occurred during office hours, which was similar to the 2 other groups. The rate of adverse obstetric or postnatal outcomes was not statistically significantly different between groups.ConclusionTimed delivery at term does not seem to be associated with an increased risk of poor perinatal outcomes. It may improve perinatal care by providing proximity to a neonatal intensive care unit and convenience for patients and providers. 相似文献
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《Vaccine》2022,40(6):904-911
BackgroundGSK initiated a Pregnancy Registry in the United States (US) for the reduced-antigen-content tetanus-diphtheria-acellular pertussis (Tdap; Boostrix, GSK) vaccine with the aim to detect and describe pregnancy outcomes in women vaccinated with Boostrix 28 days before estimated conception or during pregnancy.MethodsVoluntary reports of pregnancy exposure to Boostrix received from spontaneous and post-marketing surveillance sources in the US were assessed. Reports were classified as prospective or retrospective based on the knowledge of pregnancy outcomes at the time of reporting. For completeness, reports of exposure to Boostrix or to the Tdap-inactivated poliovirus vaccine (Boostrix-IPV, GSK) reported to the global safety database from countries outside the US were also evaluated.ResultsFrom May 2005 to August 2019, 1517 (1455 prospective and 62 retrospective) pregnancy reports were received in the Boostrix US Pregnancy Registry. Of the prospective reports, 250 had known outcomes: 244 live infants with no apparent birth defects (BDs), three live infants with BDs, and three spontaneous abortions with no apparent BDs. Of the retrospective reports, 55 had known outcomes: 33 live infants with no apparent BDs, 16 live infants with BDs, one spontaneous abortion with no apparent BDs, four stillbirths with no apparent BDs, and one stillbirth with BDs. Cumulatively, 1321 pregnancy reports (1006 for Boostrix; 315 for Boostrix-IPV) were received from countries outside the US. Of these, 163 prospective reports and 551 retrospective reports had known outcomes. Results were in line with those from the Boostrix US Pregnancy Registry.ConclusionsData currently available from the Boostrix US Pregnancy Registry and from countries outside the US suggested that exposure to Boostrix or Boostrix-IPV during pregnancy does not raise safety concerns related to adverse pregnancy outcomes or BDs. 相似文献
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目的探讨microRNA-33通过调节巨噬细胞自噬对心肌细胞胆固醇代谢受损和功能缺陷的影响。方法分别培养人单核巨噬细胞和人心肌细胞后将实验分为对照组、miR-33模拟物组(10、5.0、1.0μmol/L组)和miR-33抑制剂组(10、5.0、1.0μmol/L组)。分别测定各组巨噬细胞存活率和自噬相关蛋白表达水平、心肌细胞ABCA1和CS的蛋白表达量、胆固醇流出率、心肌细胞活力以及功能缺陷[乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)、丙二醛(MAD)]。结果各组细胞巨噬细胞存活率和自噬相关蛋白表达水平、心肌细胞ABCA1和CS的蛋白表达量、胆固醇流出率、心肌细胞活力以及功能缺陷比较差异均有统计学意义(P<0.05)。其中模拟物组自噬相关蛋白表达水平、巨噬细胞存活率、心肌细胞ABCA1和CS的蛋白表达量和心肌细胞活力高于对照组和抑制剂组,胆固醇流出率低于对照组和抑制剂组,功能缺陷均低于抑制剂组(P<0.05);随着microRNA-33模拟物浓度增大,LC3-Ⅰ、LC3-Ⅱ和ATG5、ABCA1和CS蛋白表达水平、LDH和SOD水平均显著升高,MAD水平则显著下降(P<0.05);随着microRNA-33抑制剂浓度增大,心肌细胞胆固醇流出率、MAD水平均显著升高,LC3-Ⅰ、LC3-Ⅱ和ATG5蛋白表达水平、心肌细胞活力以及LDH和SOD的水平均显著降低(P<0.05)。结论microRNA-33模拟物能够通过上调巨噬细胞自噬蛋白表达,降低心肌细胞胆固醇代谢水平和功能缺陷的发生,且在本研究范围内,其剂量越高作用效果越显著,而microRNA-33模拟物的调控作用则相反。 相似文献
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Domenico Pellegrino Lucia Calcagno Massimo Zimbone Salvatore Di Franco Antonella Sciuto 《Materials》2021,14(8)
In this study, 4H-SiC p–n junctions were irradiated with 700 keV He+ ions in the fluence range 1.0 × 1012 to 1.0 × 1015 ions/cm2. The effects of irradiation were investigated by current–voltage (I–V) and capacitance–voltage (C–V) measurements, while deep-level transient spectroscopy (DLTS) was used to study the traps introduced by irradiation defects. Modifications of the device’s electrical performances were observed after irradiation, and two fluence regimes were identified. In the low fluence range (≤1013 ions/cm2), I–V characteristics evidenced an increase in series resistance, which can be associated with the decrease in the dopant concentration, as also denoted by C–V measurements. In addition, the pre-exponential parameter of junction generation current increased with fluence due to the increase in point defect concentration. The main produced defect states were the Z1/2, RD1/2, and EH6/7 centers, whose concentrations increased with fluence. At high fluence (>1013 ions/cm2), I–V curves showed a strong decrease in the generation current, while DLTS evidenced a rearrangement of defects. The detailed electrical characterization of the p–n junction performed at different temperatures highlights the existence of conduction paths with peculiar electrical properties introduced by high fluence irradiation. The results suggest the formation of localized highly resistive regions (realized by agglomeration of point defects) in parallel with the main junction. 相似文献
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《Indian heart journal》2021,73(5):637-639
We herein report our single center experience of safety and efficacy of device closure of large sized ostium secundum atrial septal defects (OS ASD) in small children with less than 2 years of age performed over the period of 10 years from 2009 to 2019.148 symptomatic children with ASD size of more than 8 mm were included in our study. We obtained a high rate of successful deployment (98 %) with no major complications. 相似文献
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目的 分析异常生育史与遗传性家族史、孕期危险因素暴露的多重对应关系,为进一步完善出生缺陷监测系统和降低出生缺陷发生率提供新的科学依据。方法 对2003至2015年西安市各级开设产科的医疗保健机构分娩的孕28周至生后7 d的围产儿进行出生缺陷监测,并收集相关资料。结果 共监测围产儿1 236 937例,其中出生缺陷患儿10 619例,平均出生缺陷发生率为0.86%(0.70%~1.15%)。多重对应分析显示生育出生缺陷患儿(既往生育1个或2个出生缺陷患儿)与自然流产史、遗传性家族史、有毒有害物质接触史有关,既往生育≥3个出生缺陷患儿与遗传性家族史接近相同区域且距离更近,关系更密切。有自然流产史产妇(257/10 619)再次生育出生缺陷患儿类型依次为先天性心脏病、多指(趾)、神经管缺陷、先天性脑积水、唇裂合并腭裂、单纯唇裂;生育过出生缺陷患儿的产妇(135/10 619)再次生育出生缺陷患儿类型依次为唇裂合并腭裂、无脑畸形、脑积水、神经管缺陷、唇裂、马蹄内翻足。结论 异常生育史与孕期危险因素暴露和遗传性家族史均相关,既往生育≥3个出生缺陷患儿与遗传性家族史关系更密切。 相似文献