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101.
Cataloguing the effects of different types of stress on behaviour and physiology in rodent models has not been comprehensively attempted. Here, we systematically review whether chronic exposure to physical stress, psychosocial stress, or both types of stress can induce different behavioural and neurobiological outcomes in male and female rodents. We found that physical stress consistently increased depressive-like behaviour, impaired social interaction and decreased body weight, while psychosocial stress consistently increased both anxiety- and depressive-like behaviour, impaired social interaction and learning and memory, increased HPA axis activity, peripheral inflammation and microglial activation, and decreased hippocampal neurogenesis in male rodents. Moreover, we found that the combined effect of both stress types resulted in a more severe pathological state defined by increased anxiety- and depressive-like behaviour, impaired social interaction and learning and memory, increased HPA axis activity and central inflammation, and reduced hippocampal neurogenesis and neural plasticity in male rodents. Phenotypes for females were less consistent, irrespective of the type of stress exposure, on account of the limited number of studies using females. This review highlights that the type of stress may indeed matter and will help animal researchers to more appropriately choose a stress/depression model that fits their research purposes.  相似文献   
102.
《Injury》2021,52(10):3166-3172
IntroductionShock-index (SI) and systolic blood pressure (SBP) are metrics for identifying children and adults with hemodynamic instability following injury. The purpose of this systematic review was to assess the quality of these metrics as predictors of outcomes following pediatric injury.Materials and methodsWe conducted a literature search in Pubmed, SCOPUS, and CINAHL to identify studies describing the association between shock metrics on the morbidity and mortality of injured children and adolescents. We used the data presented in the studies to calculate the sensitivity and specificity for each metric. This study was registered with Prospero, protocol CRD42020162971.ResultsFifteen articles met the inclusion criteria. seven studies evaluated SI or SIPA score, an age-corrected version of SI, as predictors of outcomes following pediatric trauma, with one study comparing SIPA score and SBP and one study comparing SI and SBP. The remaining eight studies evaluated SBP as the primary indicator of shock. The median sensitivity for predicting mortality and need for blood transfusion was highest for SI, followed by SIPA, and then SBP. The median specificity for predicting these outcomes was highest for SBP, followed by SIPA, and then SI.ConclusionsCommon conclusions were that high SIPA scores were more specific than SI and more sensitive than SBP. SIPA score had better discrimination for severely injured children compared to SI and SBP. An elevated SIPA was associated with a greater need for blood transfusion and higher in-hospital mortality. SIPA is specific enough to exclude most patients who do not require a blood transfusion.  相似文献   
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目的探究钆布醇增强磁共振血管成像(MRA)在腹部动脉血管扫描的应用价值。方法前瞻性纳入2014年12月至2015年12月期间行钆布醇增强MRA检查患者112例,由两名观察者对图像质量进行分析,对大中血管行主观评分和信号值测定,对小血管进行主观评分。采用Kappa检验对两名观察者的主观评分进行一致性分析。结果最终纳入112例患者,其中96例患者因体检行腹部MRA检查,16例患者因肝脏占位行腹部MRA检查。所有患者均未发现不良反应。112例钆布醇增强MRA图像中,有2例患者因呼吸伪影严重而影响血管显影。110例MRA图像清晰,能清晰显示大中血管和小血管的起源、走行。大中血管成像的主观评分为(21.22±1.93)分,对小血管成像的主观评分为(6.24±1.33)分。对感兴趣区大中血管的信号强度测量显示信号噪声比和对比信号噪声比率分别为1093.27±331.71和897.27±333.29。两名观察者对大中血管定性分析的一致性Kappa值为0.782,对小血管定性分析的一致性Kappa值为0.772。结论钆布醇增强MRA能清晰显示大中血管,还能良好显示部分小血管,在腹部动脉血管扫描中具有良好的应用价值。  相似文献   
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106.
BackgroundAtlantoaxial instability is mainly caused by trauma. C2 nerve is usually needed to be sacrificed for adequate exposure of the lateral mass and screw insertion.ObjectivesThis study aimed to investigate the clinical outcome of postoperative complications of C1 and C2 screw-rod fixation using the Goel-Harms technique for C1-C2 instability after sacrificing the C2 nerve root.MethodsAmongst forty patients with C1-C2 pathology, twenty-seven cases were enrolled into the study, then variables, including age, sex, primary pathology, operation duration, postoperative pain, paresthesia, anesthesia, and other specific conditions, were documented. Data analyzed by an expert biostatistician. p-value < 0.05 was considered significant.ResultsRegardless of gender, the most postoperative adverse effect was occipital anesthesia (81.5%). Most of the patients (63%) had both occipital pain and anesthesia one-month post-surgery. At 3- and 6-months post-surgery, occipital pain and anesthesia were seen in 40.7% and 14.8%, respectively.ConclusionThe most common postoperative adverse effect of C2 nerve root scarification after C1-C2 fixation is occipital anesthesia followed by occipital paresthesia and pain, which are reduced in severity over time.  相似文献   
107.
AimIn this prospective study, we aimed to examine the effect of physiological and pathological changes that occur during pregnancy in regard to Meibomian Gland (MG) structure, tear film, cornea and anterior segment parameters.MethodsThe following groups were compared: 49 eyes of 49 pregnant women at 16-20 weeks of pregnancy (P16 Group), 46 eyes of 46 pregnant women at 32-36 weeks of pregnancy (P32 Group) and 51 eyes of 51 participants who were not pregnant (P0 Group). The groups were compared in terms of the first break-up time (NIF-BUT) and average break-up time (NIAvg-BUT) values. Non-contact meibography and MG loss rates were also compared.ResultsThe groups were found to be compatible in terms of age (P=0.052). The mean NIF-BUT values in the P16, P32 and P0 groups were 4.7 ±2.7, 6 ±3 and 6.7 ±3.1 seconds, respectively (P=0.055). The mean MG loss rates for the upper lid in the P16, P32 and P0 groups were 35.3%±12.6, 33.4%±11.4 and 15.5%±5.4, respectively. The loss rates for the lower lid in the P16, P32 and P0 groups were found to be 40.5%±18.6, 40.5%± 14.4 and 20.1%±8.1, respectively (P=0.000, p=0.000). The mean anterior chamber value (ACV) was found in the P16, P32 and P0 groups with 160.8 ±31.8, 150.9 ±26.5 and 165.9 ±26.5 µm3, respectively (P=0.035).ConclusionMG loss was found to be higher in pregnant groups compared to the non-pregnant groups. We found minimal instability in the tear film of the pregnant groups. We believe that pregnant women should be followed closely in terms of ocular surface diseases.  相似文献   
108.
We introduce Region of Interest Contrast Enhancement (RICE) to identify focal densities in mammograms. It aims to help radiologists: 1) enhancing the contrast of mammographic images; and 2) detecting regions of interest (such as focal densities) that are candidate masses potentially masked behind dense parenchyma. Cancer masking is an unsolved issue, particularly in breast density categories BI-RADS C and D. RICE suppresses normal breast parenchyma in order to highlight focal densities. Unlike methods that enhance mammograms by modifying the dynamic range of an image; RICE relies on the actual tissue composition of the breast. It segments Volumetric Breast Density (VBD) maps into smaller regions and then applies a recursive mechanism to estimate the ‘neighbourhood’ for each segment. The method then subtracts and updates the neighbourhood, or the encompassing tissue, from each piecewise constant component of the breast image. This not only enhances the appearance of a candidate mass but also helps in estimating the mass density. In extensive experiments, RICE enhances focal densities in all breast density types including the most challenging category BI-RADS D. Suitably adapted, RICE can be used as a precursor to any computer-aided diagnostics and detection system.  相似文献   
109.
Accurate liver tumor segmentation without contrast agents (non-enhanced images) avoids the contrast-agent-associated time-consuming and high risk, which offers radiologists quick and safe assistance to diagnose and treat the liver tumor. However, without contrast agents enhancing, the tumor in liver images presents low contrast and even invisible to naked eyes. Thus the liver tumor segmentation from non-enhanced images is quite challenging. We propose a Weakly-Supervised Teacher-Student network (WSTS) to address the liver tumor segmentation in non-enhanced images by leveraging additional box-level-labeled data (labeled with a tumor bounding-box). WSTS deploys a weakly-supervised teacher-student framework (TCH-ST), namely, a Teacher Module learns to detect and segment the tumor in enhanced images during training, which facilitates a Student Module to detect and segment the tumor in non-enhanced images independently during testing. To detect the tumor accurately, the WSTS proposes a Dual-strategy DRL (DDRL), which develops two tumor detection strategies by creatively introducing a relative-entropy bias in the DRL. To accurately predict a tumor mask for the box-level-labeled enhanced image and thus improve tumor segmentation in non-enhanced images, the WSTS proposes an Uncertainty-Sifting Self-Ensembling (USSE). The USSE exploits the weakly-labeled data with self-ensembling and evaluates the prediction reliability with a newly-designed Multi-scale Uncertainty-estimation. WSTS is validated with a 2D MRI dataset, where the experiment achieves 83.11% of Dice and 85.12% of Recall in 50 patient testing data after training by 200 patient data (half amount data is box-level-labeled). Such a great result illustrates the competence of WSTS to segment the liver tumor from non-enhanced images. Thus, WSTS has excellent potential to assist radiologists by liver tumor segmentation without contrast-agents.  相似文献   
110.
AimLncRNA MALAT1 is involved in regulation of angiogenesis, however, its expression and mechanism in infantile hemangioma (IH) are less reported. The study aimed to investigate MALAT1 in IH and to reveal the potential mechanism of MALAT1 acting on IH.MethodsIsolated form IH tissue, human CD31+ hemangioma endothelial cells (HemECs) were cultured and sorted by magnetic-activated cell sorting (MACS). Quantitative real-time (qRT)-PCR was performed to detect the expressions of MALAT1, miR-206 and VEGFA. The correlations among MALAT1, miR-206 and VEGFA were confirmed by bioinformatics analysis and dual-luciferase reporter assay. The effects of MALAT1, miR-206 and VEGFA on cell proliferation were detected by cell counting kit-8 (CCK-8) and cell colony formation assay. Flow cytometry, wound scratch, Transwell and Tube formation assay were performed to determine cell apoptosis, migration, invasion and vasoformation, respectively. Apoptosis-related proteins were determined by Western blot.ResultsThe results showed that MALAT1 and VEGFA were high-expressed and miR-206 was low-expressed in IH tissues. SiMALAT1 negatively affected the cell proliferation, migration, invasion and vasoformation of HemECs and promoted apoptosis of HemECs. Moreover, Bcl-2 expression was significantly inhibited and the expressions of Bax and c cleaved-3 were greatly promoted. MALAT1 directly targeted and inhibited the expression of miR-206, and VEGFA was predicted to be the target gene for miR-206. SiMALAT1 suppressed the cell proliferation, migration, invasion and vasoformation of HemECs through modulating miR-206/VEGFA axis.ConclusionKnock-down of MALAT1 inhibits the growth of HemECs through regulating miR-206/VEGFA axis, indicating that MALAT1 is a potential therapeutic mechanism for the treatment of IH.  相似文献   
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