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121.
The normal maturational course of the visual evoked potential (VEP) in human newborns and infants is well documented. Unfortunately, there is a paucity of data about VEP maturation in the normal preterm infant. Since this population is at risk to develop many abnormalities affecting the VEP (intraventricular hemorrhage, hydrocephalus, and retinopathy of prematurity), one must question whether such VEP data collected from this group is representative of normal maturation. To provide normative parametric developmental data we have been studying VEP development in fetal lambs. Six fetal lambs between 105 and 120 days gestational age were externalized and surgically instrumented with subcutaneous recording electrodes placed over the occipital and parietal regions. High-intensity light-emitting diodes (LEDs) externalized fiberoptic cables were secured adjacent to the orbit. from 108 to 141 days gestation, fetal VEPs were recorded in response to bright flash stimulation and the maturational topography was investigated.Over the occipital regions, the emergence of major positivities at P400 and P650 were observed beginning around 120 days gestation. Over the parietal area, the emergence of P200 and P500 components was observed by 128 days gestation. The latency-maturation functions revealed that the slope of the parietal function was steeper than the occipital counterpart, suggesting that the maturation of parietal neurons occurs at a faster rate than neuronal development in the occipital regions.  相似文献   
122.
So far it has not been established which maternal features play the most important role in newborn macrosomia. The aim of this study is to provide assessment of a hierarchy of twenty six (26) maternal characteristics in macrosomia prediction. A Polish prospective cohort of women with singleton pregnancy (N = 912) which was recruited in the years 2015–2016 has been studied. Two analyses were performed: for probability of macrosomia > 4000 g (n = 97) (vs. 755 newborns 2500–4000 g); and for birthweight > 90th percentile (n = 99) (vs. 741 newborns 10–90th percentile). A multiple logistic regression was used (with 95% confidence intervals (CI)). A hierarchy of significance of potential predictors was established after summing up of three prediction indicators (NRI, IDI and AUC) calculated for the basic prediction model (maternal age + parity) extended with one (test) predictor. ‘Net reclassification improvement’ (NRI) focuses on the reclassification table describing the number of women in whom an upward or downward shift in the disease probability value occurred after a new factor had been added, including the results for healthy and ill women. ‘Integrated discrimination improvement’ (IDI) shows the difference between the value of mean change in predicted probability between the group of ill and healthy women when a new factor is added to the model. The area under curve (AUC) is a commonly used indicator. Results. The macrosomia risk was the highest for prior macrosomia (AOR = 7.53, 95%CI: 3.15–18.00, p < 0.001). A few maternal characteristics were associated with more than three times higher macrosomia odds ratios, e.g., maternal obesity and gestational age ≥ 38 weeks. A different hierarchy was shown by the prediction study. Compared to the basic prediction model (AUC = 0.564 (0.501–0.627), p = 0.04), AUC increased most when pre-pregnancy weight (kg) was added to the base model (AUC = 0.706 (0.649–0.764), p < 0.001). The values of IDI and NRI were also the highest for the model with maternal weight (IDI = 0.061 (0.039–0.083), p < 0.001), and (NRI = 0.538 (0.33–0.746), p < 0.001). Adding another factor to the base model was connected with significantly weaker prediction, e.g., for gestational age ≥ 38 weeks (AUC = 0.602 (0.543–0.662), p = 0.001), (IDI = 0.009 (0.004; 0.013), p < 0.001), and (NRI = 0.155 (0.073; 0.237), p < 0.001). After summing up the effects of NRI, IDI and AUC, the probability of macrosomia was most strongly improved (in order) by: pre-pregnancy weight, body mass index (BMI), excessive gestational weight gain (GWG) and BMI ≥ 25 kg/m2. Maternal height, prior macrosomia, fetal sex-son, and gestational diabetes mellitus (GDM) occupied an intermediate place in the hierarchy. The main conclusions: newer prediction indicators showed that (among 26 features) excessive pre-pregnancy weight/BMI and excessive GWG played a much more important role in macrosomia prediction than other maternal characteristics. These indicators more strongly highlighted the differences between predictors than the results of commonly used odds ratios.  相似文献   
123.
唐卉 《医学文选》2001,20(3):262-263
目的:通过研究胎心监护不同图型与脐血血气分析和新生儿Apgar评分关系来探讨早期诊断胎儿宫内缺氧的方法。方法:随机收集足月单胎产妇144例在产前做胎心监护,分娩时测脐动脉血气,出生后行Apgar评分,结果:随着脐血pH值降低,胎心监护异常图型及新生儿Apgar低评分发生率越高。胎心监护正常提示胎儿宫内情况良好的准确性达80.73%,在胎儿监护异常图型中,以pH≤7.20作为缺氧标准诊断符合率为50.82%,而以Apgar评分<7分作为诊断标准的符合率仅为27.87%,各种胎心监护异常图形对胎儿预后影响差异有显著意义,P<0.005,结论:正常胎心监护图型预报胎儿预后好的准确率高,胎心监护异常时,应严密监护,根据胎心率异常的程度,胎儿能够娩出的时间,选择恰当的处理方法,即可减少围产儿病率及死亡率。  相似文献   
124.
为促进伤口以完全再生的方式无瘢痕或较少瘢痕愈合 ,在实验羊背部脊椎两侧制做伤口模型 ,用羊水、胎皮、脐血等不同成分对伤口进行治疗 ,并于治疗后 1、3、7、1 4d取材 ,分别做HE、马宋三色染色 ,7d组做电镜切片 ,观察疗效。结果 :同期内羊水组、胎皮组及脐血组比云南白药组及生理盐水组炎症清除反应及肉芽、胶原生长好 ,但未发现有明显减少瘢痕愈合的作用。结果提示 :胎羊不同组分 (羊水、胎皮、脐血 )可促进伤口愈合 ,缩短愈合时间。  相似文献   
125.
目的 探讨延期妊娠并发羊水过少对母婴的影响。方法 采用回顾性分析方法,对延期妊娠分娩的产妇羊水正常组244例及羊水过少组96例进行对比分析。结果 羊水过少组中羊水Ⅱ度以上粪染、胎盘成熟Ⅲ^ 级及胎盘钙化、胎儿宫内窘迫、新生儿窒息率、产后出血率及剖宫产率明显高于羊水正常组。结论 羊水过少是胎儿宫内慢性缺氧最敏感的特异性指标,无论是延期妊娠还是过期妊娠一经确珍,应积极引产,估计短时间内不能分娩,宜行剖宫产结束妊娠。  相似文献   
126.
目的 了解胎儿脐带绕颈时对胎儿安危及窘迫和缺氧的影响程度。方法 采用日本Aloka-630型超声诊断仪,孕妇孕周为28-42周。结果 二维超声诊断胎儿脐带绕颈136例,经分娩证实129例。符合率94.85%。结论 二维超声诊断与分娩后证实比较,超声是诊断脐带绕颈的可靠方法之一。为分娩方式提供依据。  相似文献   
127.
目的:观察乙型肝炎病毒通过产妇传播在胎儿肺组织中表达的情况。方法:采集40例乙型肝炎产妇娩下的死胎,常规尸检,取肺组织,SP法检测HBsAg;回访产妇产前静脉血HBV的检测结果。结果:HBsAg阳性颗粒在死胎的肺泡上皮细胞细胞质、肺血管中及肺泡囊、肺泡管、细支气管表面呈点、灶状发布,肺泡上皮细胞核不着色。HBV呈大三阳的产妇较HBV呈单项阳性、小三阳的产妇分娩的死胎肺组织中HBsAg阳性率、肺泡上细胞变性、肺羊水栓塞发生率明显升高,差异显著(P<0.05);HBV呈单项阳性、小三阳的产妇分娩的死胎肺组织中HBsAg阳性率比较,差异不显著(P>0.05)。结论:产妇静脉血HBV大三阳是乙型肝炎病毒通过母婴垂直传播在胎儿肺组织中表达的高危因素。  相似文献   
128.
129.
基质金属蛋白酶是一类锌依赖性内肽酶,可降解大多数细胞外基质。膜1型基质金属蛋白酶(membrane type-1 matrix metalloproteinase,MT1-MMP或MMP14)属于基质金属蛋白酶家族,是唯一一种能够直接促进细胞向3D胶原蛋白基质入侵的胶原酶。骨细胞胞外基质在骨形成和骨吸收过程中发挥重要作用,MT1-MMP通过影响胞外基质引起骨骼相关的病理、生理变化。本文拟就近年MT1-MMP在骨代谢作用中的研究进展进行综述,旨在为MT1-MMP在骨代谢疾病的药理干预、骨生物工程中的应用提供新思路。  相似文献   
130.
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