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101.
Over the vast Northwest China, arid desert contains high concentrations of sulfate, chloride, and other chemicals in the ground water, which poses serious challenges to infrastructure construction that routinely utilizes portland cement concrete. Rapid industrialization in the region has been generating huge amounts of mineral admixtures, such as fly ash and slags from energy and metallurgical industries. These industrial by-products would turn into waste materials if not utilized in time. The present study evaluated the suitability of utilizing local mineral admixtures in significant quantities for producing quality concrete mixtures that can withstand the harsh chemical environment without compromising the essential mechanical properties. Comprehensive chemical, mechanical, and durability tests were conducted in the laboratory to characterize the properties of the local cementitious mineral admixtures, cement mortar and portland cement concrete mixtures containing these admixtures. The results from this study indicated that the sulfate resistance of concrete was effectively improved by adding local class F fly ash and slag, or by applying sulfate resistance cement to the mixtures. It is noteworthy that concrete containing local mineral admixtures exhibited much lower permeability (in terms of chloride ion penetration) than ordinary portland cement concrete while retaining the same mechanical properties; whereas concrete mixtures made with sulfate resistance cement had significantly reduced strength and much increased chloride penetration comparing to the other mixtures. Hence, the use of local mineral admixtures in Northwest China in concrete mixtures would be beneficial to the performance of concrete, as well as to the protection of environment. 相似文献
102.
Christopher Phillips Sarah J. Shepherd Amy Nowack Kaibao Nie Chris R.S. Kaneko Jay T. Rubinstein Leo Ling James O. Phillips 《Journal of the Association for Research in Otolaryngology》2016,17(1):19-35
Implanted vestibular neurostimulators are effective in driving slow phase eye movements in monkeys and humans. Furthermore, increases in slow phase velocity and electrically evoked compound action potential (vECAP) amplitudes occur with increasing current amplitude of electrical stimulation. In intact monkeys, protracted intermittent stimulation continues to produce robust behavioral responses and preserved vECAPs. In lesioned monkeys, shorter duration studies show preserved but with somewhat lower or higher velocity behavioral responses. It has been proposed that such changes are due to central adaptive changes in the electrically elicited vestibulo-ocular reflex (VOR). It is equally possible that these differences are due to changes in the vestibular periphery in response to activation of the vestibular efferent system. In order to investigate the site of adaptive change in response to electrical stimulation, we performed transtympanic gentamicin perfusions to induce rapid changes in vestibular input in monkeys with long-standing stably functioning vestibular neurostimulators, disambiguating the effects of implantation from the effects of ototoxic lesion. Gentamicin injection was effective in producing a large reduction in natural VOR only when it was performed in the non-implanted ear, suggesting that the implanted ear contributed little to the natural rotational response before injection. Injection of the implanted ear produced a reduction in the vECAP responses in that ear, suggesting that the intact hair cells in the non-functional ipsilateral ear were successfully lesioned by gentamicin, reducing the efficacy of stimulation in that ear. Despite this, injection of both ears produced central plastic changes that resulted in a dramatically increased slow phase velocity nystagmus elicited by electrical stimulation. These results suggest that loss of vestibular afferent activity, and a concurrent loss of electrically elicited vestibular input, produces an increase in the efficacy of a vestibular neurostimulator by eliciting centrally adapted behavioral responses without concurrent adaptive increase of galvanic afferent activation in the periphery. 相似文献
103.
Epstein-Barr virus gene polymorphism in different parts of the same nasopharyngeal carcinoma patient
Yahong Nie Yingjuan Sun Yun Wang Chengyu Liu Chengquan Zhao Bing Luo 《Archives of virology》2013,158(5):1031-1037
In most previous studies, comparisons of Epstein-Barr virus (EBV) gene polymorphisms and genotypes were made between strains from tumors and normal throat washings (TWs) from different individuals. However, it remains controversial whether different EBV subtypes are present in different parts of the same NPC patient. In order to address this question, in this study, we compared the genotypes in sets of paired throat washings (TW) and paraffin-embedded tissues of 20 patients with nasopharyngeal carcinoma (NPC), and we found the same genotype in throat washings (TWs) and tumor cells from the same individual in most cases. The subtypes of EBER and EBNA1 genes were furthermore sequenced, and identical EBV strains were identified in tumor tissues and TWs. In conclusion, different sites of the same individual are infected by the same EBV strains, except for a few differences in occasional cases, suggesting that the EBV subtype detected in throat washings is a reasonable guide to the subtype present in the carcinoma tissue. 相似文献
104.
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106.
Tian-gang Li MD Bin Ma MD Fang Nie MD Mei-juan Peng MD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(7):1105-1108
Coronary artery fistula is rare in prenatal diagnosis. We have reported a case diagnosis of coronary artery fistula by using high-definition flow (HD-flow) render mode and spatiotemporal image correlation (STIC), and then evaluated the postnatal outcomes in our hospital. 相似文献
107.
目的 分析《药物分析》课程在当今药学本科教育培养过程中的现状,探索《药物分析》课程在新时代药学教育背景下的教学改革与创新,构建符合药学培养要求、满足社会市场需要的复合型药学人才培养模式。方法 第一阶段,开展教学改革的建议和需求调查;第二阶段,开展《药物分析》课程改革探索与实践;第三阶段,教学效果评价。结果 需求调查显示《药物分析》课程的教学内容、课程设计、教学手段亟须进一步优化和拓展。结论 该课程通过调整教学内容、拓展教学手段、创新多元化实践教学、融入"课程思政"建设等,激发了学生的学习兴趣和创新精神,强化了学生理论素养和实践能力,培养了其国际化视野和崇高的职业道德。 相似文献
108.
Jing Li Rui Wang Lei Yang Qi Wu Qinwan Wang Zhengchao Nie Yongchun Yu Ji Ma Qiuhui Pan 《International journal of clinical and experimental pathology》2015,8(6):6377-6386
Nestin, a member of type VI intermediate filament protein family, is widely expressed in mammalian nervous tissue and stem/precursor cells of non-neuronal normal tissues. Nestin has also been investigated to determine possible tumor-promoting functions. However, whether Nestin is involved in colorectal cancer (CRC) cells remains unclear. In this report, Nestin expression was upregulated in stromal cells of human CRC tissues. Endogenous Nestin expression in CRC cell lines SW480 and HCT116 was knocked down by a lentivirus. MTT and colony formation assays revealed that Nestin deletion significantly inhibits the proliferation of CRC cell lines; flow cytometer analysis showed that Nestin deletion causes cell cycle arrest at S phase. Transwell chamber and wound healing scratch assays also revealed that Nestin deletion suppresses cell migration. Our findings indicated that Nestin plays an essential role in CRC progression; thus, Nestin can be applied as a therapeutic target of CRC. 相似文献
109.
Teng-Fei Yu Wen He Cong-Gui Gan Ming-Chang Zhao Qiang Zhu Wei Zhang Hui Wang Yu-Kun Luo Fang Nie Li-Jun Yuan Yong Wang Yan-Li Guo Jian-Jun Yuan Li-Tao Ruan Yi-Cheng Wang Rui-Fang Zhang Hong-Xia Zhang Bin Ning Hai-Man Song Shuai Zheng Yi Li Yang Guang 《中华医学杂志(英文版)》2021,134(4):415
BackgroundThe current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions. In China, breast masses are divided into four categories according to the treatment method: inflammatory masses, adenosis, benign tumors, and malignant tumors. These categorizations are important for guiding clinical treatment. In this study, we aimed to develop a convolutional neural network (CNN) for classification of these four breast mass types using ultrasound (US) images.MethodsTaking breast biopsy or pathological examinations as the reference standard, CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers. The patients were randomly divided into training and test groups (n = 1810 vs. n = 1813). Separate models were created for two-dimensional (2D) images only, 2D and color Doppler flow imaging (2D-CDFI), and 2D-CDFI and pulsed wave Doppler (2D-CDFI-PW) images. The performance of these three models was compared using sensitivity, specificity, area under receiver operating characteristic curve (AUC), positive (PPV) and negative predictive values (NPV), positive (LR+) and negative likelihood ratios (LR−), and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators, between images from different hospitals with AUC, and with the performance of 37 radiologists.ResultsThe accuracies of the 2D, 2D-CDFI, and 2D-CDFI-PW models on the test set were 87.9%, 89.2%, and 88.7%, respectively. The AUCs for classification of benign tumors, malignant tumors, inflammatory masses, and adenosis were 0.90, 0.91, 0.90, and 0.89, respectively (95% confidence intervals [CIs], 0.87–0.91, 0.89–0.92, 0.87–0.91, and 0.86–0.90). The 2D-CDFI model showed better accuracy (89.2%) on the test set than the 2D (87.9%) and 2D-CDFI-PW (88.7%) models. The 2D model showed accuracy of 81.7% on breast masses ≤1 cm and 82.3% on breast masses >1 cm; there was a significant difference between the two groups (P < 0.001). The accuracy of the CNN classifications for the test set (89.2%) was significantly higher than that of all the radiologists (30%).ConclusionsThe CNN may have high accuracy for classification of US images of breast masses and perform significantly better than human radiologists.Trial registrationChictr.org, ChiCTR1900021375; http://www.chictr.org.cn/showproj.aspx?proj=33139. 相似文献
110.
目的建立多重荧光PCR-熔解曲线法,并评价其同时检测假丝酵母菌、曲霉菌及新型隐球菌的诊断价值。
方法建立多重荧光PCR-熔解曲线法并对其检测体系进行优化。收集临床高度怀疑为侵袭性真菌感染(IFI)的各类临床样本179例,其中血液65例、深部痰液35例、尿液30例、脑脊液18例、胸腹水12例、肺泡灌洗液10例、新鲜肺组织9例。通过敏感性、特异性、重复性实验验证多重荧光PCR-熔解曲线法的检测性能,并应用受试者工作特征(ROC)曲线评价该方法的诊断效能。
结果建立的多重荧光PCR-熔解曲线法可同时检测8种常见病原真菌,包括4种假丝酵母菌(白假丝酵母菌、热带假丝酵母菌、光滑假丝酵母菌、克柔假丝酵母菌)、3种曲霉菌(烟曲霉、黄曲霉、黑曲霉)和新型隐球菌。其最低检测限为1 × 104 cfu/mL,且常见细菌无扩增反应,重复性实验解链温度波动小于0.5 ℃。179例临床样本中,以培养法、镜检法、病理诊断等"金标准"方法诊断IFI阳性为112例,多重荧光PCR-熔解曲线法检测阳性为96例。多重荧光PCR-熔解曲线法同时检测假丝酵母菌、曲霉菌及新型隐球菌的敏感度为0.857,特异度为0.970,阳性预测值为0.980,阴性预测值为0.802,ROC曲线下面积为0.914,95%置信区间为0.868 ~ 0.959,P < 0.001。
结论本研究建立的多重荧光PCR-熔解曲线法可快速、准确、高通量同时检测假丝酵母菌、曲霉菌及新型隐球菌,对于IFI的早期诊断具有重要意义。 相似文献