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目的 评价美国国家电器制造协会(National Electrical Manufactures Association, NEMA)最新标准(NU 2-2018)在正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography, PET/CT)设备性能检测中的作用。 方法 依据最新的NEMA NU 2-2018标准,检测西门子Biograph Vision PET/CT的空间分辨率、灵敏度、散射分数、计数丢失、随机符合、飞行时间分辨率、计数丢失率和随机符合校正精度、图像质量、衰减和散射校正精度及PET与CT配准精度指标。 结果 距视野中心1 cm处横向和轴向空间分辨率分别为3.75 mm和3.76 mm;在视野中心和轴向10 cm处的灵敏度分别为16.83 kcps/MBq和16.67 kcps/MBq;放射性浓度为27.37 kBq/mL时,最大等效噪声计数率为258.26 kcps,散射分数为38.58%;系统时间分辨率为209.82 ps;图像质量模型的对比度恢复系数范围为88.9%~96.2%,背景变异系数范围为2.05%~6.80%,平均肺插件残余误差为2.43%;计数丢失和随机符合校正最大误差为3.9%;距离床板末端 5 cm 和 100 cm处,在距视野中心Y轴1 cm处,PET和CT的配准精度分别为0.46 mm和1.07 mm,在距视野中心X轴20 cm处,PET和CT的配准精度分别为1.06 mm和1.45 mm,在距视野中心Y轴20 cm处PET和CT的配准精度分别为0.85 mm和1.15 mm。 结论 NEMA NU 2-2018标准检测条件更加接近临床,能更好地反映PET/CT设备的系统性能。  相似文献   
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《Immunobiology》2022,227(6):152284
Asthma is a disorder characterized by airflow obstruction, inflammation, declining airway function, bronchial hyperresponsiveness and tissue remodelling. Probiotics are defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host”. The use of probiotics is becoming increasingly studied and recent evidence has suggested that it may provide therapeutic benefits in asthma and other diseases. Lactobacillus delbrueckii UFV-H2b20 fulfils all the requirements to be classified as probiotic. Previous studies have already shown the ability of L. delbrueckii UFV-H2b20 to stimulate the immune system. Our objective was to evaluate the protective effects of L. delbrueckii UFV-H2b20 in experimental allergic asthma. We used a murine model of ovalbumin-induced allergic airway inflammation to mimic allergic asthma. Oral treatment with L. delbrueckii UFV-H2b20 improves respiratory parameters and inhibits the inflammatory response in the lungs by decreasing the numbers of inflammatory monocytes, eosinophils and alveolar macrophages, as well as IgE levels. Treatment increased the IFN-γ/IL-4 cytokine ratio. Levels of IL-10 in the lungs were also increased in treated animals. Our results also showed that the probiotic administration increases the number of CD39+CD73+ T regulatory lymphocytes in the lung, suggesting a role for purinergic signals in the regulation of inflammation promoted by the treatment. Understanding the mechanisms of modulation of the immune system by probiotics could allow the development of probiotic preparations that are safe and have a direct action. Our results suggest that oral administration of L. delbrueckii UFV-H2b20 could be helpful to treat chronic inflammatory airway diseases, such as asthma.  相似文献   
4.
为了实现超声对比剂(也称超声造影剂)高效、合理、安全、规范化输注,国内相关医护专家总结了国内外文献证据及临床经验,按照循证医学原则充分讨论后,制订了该共识,旨在为我国超声对比剂安全输注的规范化和标准化提供参考意见。共识介绍了超声对比剂的应用现状和安全性、相关法规与流程,造影前、中、后的规范化护理,并提出16条推荐意见。提出目前国内批准上市使用的超声对比剂安全性高,建议医护人员根据最新说明书或专家共识进行配药和给药,并从造影室管理、风险预案、人员资质等方面予以规范。  相似文献   
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目的探讨食管肿瘤与头颈部肿瘤患者在调强放疗期间营养状况和生活质量的相关性。方法选取2018年11月至2019年5月肿瘤放疗患者进行研究,采用NRS 2002和PG-SGA对患者进行营养评估,运用EORTC QLQ-C30进行生活质量测评,并分析两者之间相关性。结果41例患者中食管肿瘤23例,头颈部肿瘤18例,放疗后体重丢失35例,占85.36%,其中丢失≥5%体重患者19例,占46.34%,体重丢失>10%患者2例,占4.88%,平均丢失体重3.6kg。41例患者中合并骨髓抑制31例、低蛋白血症15例,电解质紊乱24例。放疗后,41例患者在总健康水平及功能方面得分均低于放疗前(P<0.05),症状方面如疼痛、疲倦、食欲丧失等得分均高于放疗前(P<0.05)。总健康水平、躯体功能、疼痛和食欲丧失等方面与营养状况存在明显相关性(P<0.05);而社会功能、情绪功能、气促和便秘与营养状况无明显相关性(P>0.05)。结论肿瘤患者在放疗期间的营养状况和生活质量存在相关性,应重视肿瘤放疗患者的营养评估及干预,改善患者躯体功能、疼痛、食欲等方面的生活质量,从而提高放疗效果。  相似文献   
7.
《Vaccine》2019,37(37):5535-5543
Recent studies have suggested that among those receiving seasonal influenza vaccine (SIV), reduced immunogenicity is observed in recently vaccinated (RV; within the past season or 2) persons when compared with those not recently vaccinated (NRV). We performed a meta-analysis to assess the effect of recent immunization with SIV on serum H5 hemagglutination inhibition (HAI) antibody responses after influenza A/H5N1 vaccination using data from a series of randomized controlled trials. The primary outcome was seroconversion measured by HAI assays following receipt of 2 doses of H5N1 vaccine. The geometric mean titer (GMT) of serum HAI antibody after vaccination was the secondary outcome. Analyses were performed using propensity score (PS) matching. The PS for each individual in the meta-analysis cohort was calculated using logistic regression and covariates included age, gender, race, antigen dose, adjuvant, statin use and vaccine manufacturer. 2015 subjects enrolled in 7 clinical trials were eligible for inclusion in the meta-analysis cohort; among these, 915 (45%) were RV. 901 RV subjects were matched (1:1) with replacement to a subject who was NRV. Subjects who received SIV within the previous season were significantly less likely to seroconvert following H5N1 vaccination (adjusted odds ratio 0.76; 95%CI 0.60–0.96; p = 0.024), and the GMT was 18% higher among NRV subjects (GM ratio of HAI antibody 1.18; 95%CI 1.04–1.33; p = 0.008). Further work is needed to better define the effects of, and mechanisms contributing to, reduced immune responses to H5N1 vaccine among RV subjects.  相似文献   
8.
PurposeTo identify risk factors for hypertensive crisis (HC) during ultrasound-guided percutaneous microwave (MW) ablation of adrenal neoplasms.Materials and MethodsPatients who underwent MW ablation for adrenal tumors between April 2006 and November 2017 were retrospectively identified for this study (51 consecutive patients; 35 males, 16 females; mean age, 55 years; range, 15–85 years). A total of 77 MW ablation treatments were performed for 67 tumors (24 primary [9 pheochromocytomas, 8 adenomas, and 7 cortical carcinomas]; and 43 metastases [22 hepatocellular carcinoma, 8 renal cell carcinoma, 5 non-small cell lung cancer, 4 colorectal cancer, 3 liposarcoma, and 1 malignant fibrous histiocytoma]). The mean diameter of the adrenal tumors was 4.6 cm (range, 1.2–16.2 cm). Information about patient demographics, imaging studies, pathology and laboratory results, procedure records, and clinical outcomes was retrieved and analyzed. Statistical analysis was then performed to determine potential risk factors for HC.ResultsOf the 77 MW ablation procedures, HC occurred in 13 (16.9%). A significantly higher risk of HC was observed in patients with pheochromocytoma (odds ratio [OR], 9.037; 95% confidence interval [CI], 1.731–47.172; P = .009), body mass index <24 kg/m2 (OR, 5.167; 95% CI, 1.060–25.194; P = .042), dominant tumor size ≤4.5 cm (OR, 4.023; 95% CI, 1.011–16.005; P = .048), and pre-procedural systolic blood pressure ≥130 mmHg (OR, 0.242; 95% CI, 0.068–0.861; P = .029).ConclusionHC can occur during MW ablation in patients with either primary or metastatic adrenal tumors. Pheochromocytoma, body mass index, tumor size, and pre-procedural systolic blood pressure appear to be significant risk factors for the occurrence of HC.  相似文献   
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目的 :分析Lenke 5型青少年特发性脊柱侧凸(AIS)患者颈椎矢状位曲度(CSA)在后路矫形术后改变的特点。方法:回顾性分析2011年7月~2017年7月解放军总医院脊柱外科收治的43例Lenke 5型AIS患者的临床资料。在术前、术后及末次随访时的X线片上测量颈椎前凸角(CL)、胸椎后凸角(TK)、胸腰段后凸角(TLK)、腰椎前凸角(LL)、融合节段内腰椎前凸角(LIF)、C7矢状位垂直距离(SVA)。同时统计患者的基本资料,包括性别、年龄、Risser征、随访时间、融合节段椎体数目(NVF)及术前胸腰段/腰弯(TL/L Curve,TL/L C)。依据患者术前CSA分为颈椎前凸组(L组,术前CL0°)、颈椎后凸组(K组,术前CL≥0°);依据患者末次随访时CSA较术前的改变分为颈椎前凸增加组(I组)与颈椎前凸减少组(D组)。使用t检验分析L组与K组、I组与D组对应参数的差异性,使用LSD-t检验分析各组内术前、术后、末次随访时参数的差异。使用Pearson相关性检验分析CL与I组和D组各参数的相关性。检验水准为双侧α=0.05。结果:43例患者中男10例,女33例;年龄15.90±4.98岁,随访时间22.84±14.10个月。L组15例,K组17例;I组26例,D组17例。L组与K组、I组与D组的基本资料无显著性差异。所有患者末次随访时TK较术前增加(P=0.000);术后TLK与术前比较有显著性差异(P=0.000);CL在术前、术后及末次随访时无统计学差异。L组与K组术前CL(P=0.000)、LIF(P=0.029)、SVA(P=0.003)差异有统计学意义(P0.05)。K组末次随访时CL较术前改善(P=0.025),TK较术前增加(P=0.000);术后TLK较术前减小(P=0.002)并维持至末次随访(P=0.002)。I组与D组术前LL(P=0.043)、CL(P=0.009)有显著性差异(P0.05)。I组末次随访时CL较术前改善(P=0.008),TK较术前(P=0.000)及术后(P=0.001)增加;术后TLK较术前减小(P=0.005)并维持到末次随访时(P=0.006)。D组术后LL较术前增加(P=0.011)并维持到末次随访(P=0.001)。I组术前CL与TK、SVA有相关性;D组CL术前与LL、SVA,术后与TLK、SVA,末次随访时与TLK有相关性。结论:术前颈椎后凸的患者较颈椎前凸的患者在术后CSA的改善更为明显;随访中TK增加、术后TLK改善可能有助于CSA的改善;术后只有LL增加而无TK、TLK的改变则可能不会引起CSA改善。  相似文献   
10.
IntroductionRhabdomyolysis (RM) is a complex set of clinical syndromes involving the rapid dissolution of skeletal muscles. The early detection of patients who need renal replacement therapy (RRT) is very important and may aid in delivering proper care and optimizing the use of limited resources.MethodsRetrospective analyses of the following three databases were performed: the eICU Collaborative Research Database (eICU-CRD), the Medical Information Mart for Intensive Care III (MIMIC-III) database and electronic medical records from the First Medical Centre of the Chinese People's Liberation Army General Hospital (PLAGH). The data from the eICU-CRD and MIMIC-III datasets were merged to form the derivation cohort. The data collected from the Chinese PLAGH were used for external validation. The factors predictive of the need for RRT were selected using a LASSO regression analysis. A logistic regression was selected as the algorithm. The model was built in Python using the ML library scikit-learn. The accuracy of the model was measured by the area under the receiver operating characteristic curve (AUC). R software was used for the LASSO regression analysis, nomogram, concordance index, calibration, and decision and clinical impact curves.ResultsIn total, 1259 patients with RM (614 patients from eICU-CRD, 324 patients from the MIMIC-III database and 321 patients from the Chinese PLAGH) were eligible for this analysis. The rate of RRT was 15.0% (92/614) in the eICU-CRD database, 17.6% (57/324) in the MIMIC-III database and 5.6% in the Chinese PLAGH (18/321). After the LASSO regression selection, eight variables were included in the RRT prediction model. The AUC of the model in the training dataset was 0.818 (95% CI 0.78–0.87), the AUC in the test dataset was 0.794 (95% CI 0.72–0.86), and the AUC in the Chinese PLAGH dataset (external validation dataset) was 0.820 (95% CI 0.70–0.86).ConclusionsWe developed and validated a model for the early prediction of the RRT requirement among patients with RM based on 8 variables commonly measured during the first 24 h after admission. Predicting the need for RRT could help ensure appropriate treatment and facilitate the optimization of the use of medical resources.  相似文献   
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