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1.
The distribution of mannan binding protein (MBP) in blood donorsera was determined by enzyme-linked immunosorbent assay toestablish normal concentrations. Abnormally low MBP concentrationswere found in 16% (21 out of 135) of female partners and 14%(15 out of 108) of male partners of couples experiencing recurrentmiscarriage, compared with <5% of obstetrically normal controls(P < 0.005). This relationship was even stronger (9.5 versus1.0%) and more significant (P < 0.002) when only subjectspresumed to be homozygous for the mutant allele responsiblefor MBP deficiency were considered. By immunohistochemistry,MBP could be demonstrated in first trimester placenta. We suggestthat low concentrations of MBP within the feto-placental unitincrease susceptibility to fetal loss, possibly via an infection-inducedplacental cytokine imbalance.  相似文献   
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Implant migration can be accurately quantified by model‐based Roentgen stereophotogrammetric analysis (RSA), using an implant surface model to locate the implant relative to the bone. In a clinical situation, a single reverse engineering (RE) model for each implant type and size is used. It is unclear to what extent the accuracy and precision of migration measurement is affected by implant manufacturing variability unaccounted for by a single representative model. Individual RE models were generated for five short‐stem hip implants of the same type and size. Two phantom analyses and one clinical analysis were performed: “Accuracy‐matched models”: one stem was assessed, and the results from the original RE model were compared with randomly selected models. “Accuracy‐random model”: each of the five stems was assessed and analyzed using one randomly selected RE model. “Precision‐clinical setting”: implant migration was calculated for eight patients, and all five available RE models were applied to each case. For the two phantom experiments, the 95%CI of the bias ranged from ?0.28 mm to 0.30 mm for translation and ?2.3° to 2.5° for rotation. In the clinical setting, precision is less than 0.5 mm and 1.2° for translation and rotation, respectively, except for rotations about the proximodistal axis (<4.1°). High accuracy and precision of model‐based RSA can be achieved and are not biased by using a single representative RE model. At least for implants similar in shape to the investigated short‐stem, individual models are not necessary. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:903–910, 2016.
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Resting respiratory sinus arrhythmia (RSA) and shyness were examined as predictors of effortful control (EC) in a sample of 101 preschool-age children. Resting RSA was calculated from respiration and heart rate data collected during a neutral film; shyness was measured using parents’, preschool teachers’, and classroom observers’ reports; and EC was measured using four laboratory tasks in addition to questionnaire measures. Principal components analysis was used to create composite measures of EC and shyness. The relation between RSA and EC was moderated by shyness, such that RSA was positively related to EC only for children high in shyness. This interaction suggests that emotional reactivity affects the degree to which RSA can be considered a correlate of EC. This study also draws attention to the need to consider the measurement context when assessing resting psychophysiology measures; shy individuals may not exhibit true baseline RSA responding in an unfamiliar laboratory setting.  相似文献   
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BackgroundIt has been proposed that the introduction of new hip implant technology in orthopedic surgery be conducted in a more controlled manner in order to properly ensure patient safety and the likelihood of favorable outcomes. This stepwise introduction would first require a prospective randomized study in a small cohort of patients, using radiostereometric analysis (RSA). The aim of this study is to determine if the recent literature supports the use of RSA as an early screening tool to accurately predict the long-term outcomes of cementless femoral stems.MethodsA review of the recent published literature identified 11 studies that used RSA to predict the long-term stability of a cementless femoral component. These RSA predictive data were compared to the 10-year revision rate reported in the Australian Registry or in the published literature to determine its reliability.ResultsRSA data did not universally predict long-term stem fixation. In 2 of the 11 cases (18%), the RSA study incorrectly predicted the ability of the cementless stem to reliably osseointegrate. Of the 9 stems considered stable in the RSA studies, the 10 year registry and literature data confirmed that 6 implants had a low revision rate and were well performing. One stem has not performed well clinically and has been listed as having a higher than anticipated rate of revision in the registry. Two stems do not have sufficient follow-up. Of the 2 stems RSA predicted to do poorly, 1 is well performing at 10 years, and 1 has a high revision rate at 8 years.ConclusionIn the stepwise introduction of new hip implants, RSA should be best considered as an adjunct tool in deciding whether or not an implant should be evaluated in a larger multicenter clinical studies, rather than the sole criterion.  相似文献   
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探索HLA-E分子的表达对习惯性流产(recurrent spontaneous abortion,RSA)及妊高症(pregnancy-induced hypertension,PIH)患者外周血γδT细胞细胞毒效应的影响。通过固相抗体法体外分离并扩增外周γδT血细胞作为效应细胞,以HLA-E转染的LcL721.221细胞(.221E)及滋养层细胞JAR作为靶细胞,采用4 h乳酸脱氢酶(LDH)释放试验观察NK细胞对靶细胞的细胞毒效应。结果显示,来自RSA、PIH及正常对照组的γδ细胞均不能有效杀伤HLA-E转染的.221E细胞及JAR细胞,但未经HLA-E转染的LcL721.221细胞则被溶解;抗HLA-E单抗3D12及抗CD94单抗HP-3B1的阻断可以分别部分恢复效应细胞对靶细胞LcL721.221E的杀伤,但对JAR细胞没有影响;与正常对照组相比,RSA及PIH患者外周血γδT细胞对.221、.221E及JAR细胞的细胞毒活性没有显著性差异(P>0.05)。这说明HLA-E分子的体外表达可以保护靶细胞防止γδT细胞的杀伤,该保护机制主要是通过γδT细胞受体CD94/NKG2对靶细胞表面HLA-E分子的识别来实现的;滋养层细胞对γδT细胞杀伤的抵抗可能存在MHC I类非依赖的机制。  相似文献   
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The present research investigated whether cardiac vagal control (as measured by respiratory sinus arrhythmia, RSA) predicts an individual's predisposition to suppress negative emotional expressions. One hundred thirty-six participants watched either a negative film or a neutral film. Facial expressions were recorded during the film and subjective emotional responses were assessed afterwards. Participants performed verbal and spatial working memory tasks both before and after the film clips. We found that resting RSA modulated the degree of coherence between facial expressions of emotion and subjective emotional experience in the negative film condition. Specifically, participants with higher resting RSA expressed less but reported feeling just as much negative emotion as those with lower resting RSA. Moreover, higher resting RSA predicted smaller pre-film to post-film improvements in spatial working memory performance in the negative film condition, suggesting that expressive suppression among high RSA participants temporarily undermined the operation of working memory. In the neutral film condition, resting RSA did not relate to expressive or subjective responses or subsequent working memory performance. These results support the notion that cardiac vagal control reflects an internal marker of self-regulatory tendencies and suggest that spontaneous self-regulation associated with individual differences in resting RSA may temporarily deplete self-regulatory resources.  相似文献   
9.
Individuals born at extremely low birth weight (ELBW; < 1000 g) are exposed to early adversity in multiple forms. Given that substantial development of the autonomic nervous system (ANS) occurs during the third trimester of gestation, ANS functioning may be altered in adults who were born before reaching 28 weeks of gestational age. The aims of the study were to: 1) determine whether two indices of ANS functioning [resting heart period (HP) and respiratory sinus arrhythmia (RSA)], differed between adult ELBW survivors and normal birth weight (NBW) controls, and 2) ascertain whether ANS functioning was differentially vulnerable to age-related decline in the ELBW participants. Resting HP and RSA (reflecting cardiac efficiency and responsive cardiac control, respectively) were assessed in 30 non-impaired ELBW survivors and 47 NBW controls at ages 22–26 and again at 30–35 years. At each assessment, resting RSA was significantly lower in the ELBW group than in the NBW comparison group. In addition, individual differences in RSA within the ELBW group were poorly preserved over time. These findings are suggestive of a premature decline in parasympathetic functioning in some adult ELBW survivors.  相似文献   
10.
ObjectiveTo evaluate the effectiveness of etanercept in the treatment of refractory recurrent spontaneous abortion with innate immune disorders.Materials and methodsA randomized controlled trial in patients with refractory innate immune RSA was conducted in our hospital. 188 patients were selected, all with at least 4 consecutive miscarriages and caused by innate immunity disorders. Patients were randomly allocated into 2 groups. One group (n = 95) used etanercept 25 mg per week starting from the first day after menstruation, while the other (n = 93) with placebo. Delivery of a healthy baby without malformations was regarded as the primary outcome.ResultsIn etanercept group, 85 (89.47%) patients delivered a healthy baby, while in placebo group, this number was only 67 (72.04%) [P = 0.01, OR = 3.30; 95% CI(1.49~7.32)]. Significantly lower levels of TNF-α and NK cell activity were observed in gestation weeks 4–10 in etanercept group versus placebo group (P < 0.05).ConclusionThe results provide a proof of principle that etanercept can be an attractive therapeutic strategy for refractory innate immune RSA.  相似文献   
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