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31.
目的 探讨口服硝酸盐对大鼠背部随意皮瓣的影响,以硝酸盐-亚硝酸盐-NO通路为切入点,探讨其可能的机制。方法 将24只雄性Wistar大鼠随机分为硝酸盐组、氯化钠组和对照组,每组8只。采用改良大鼠背部随意皮瓣制作方法造模。硝酸盐干预组在术前7 d及术后每天口服0.5 mmol/L硝酸钠,氯化钠组每天口服等量氯化钠,对照组每天口服蒸馏水。术后第7天,检测各组皮瓣的存活情况,大鼠血清中硝酸盐、亚硝酸盐、肿瘤坏死因子(tumor necrosis factor alpha,TNF-a)和白介素6(interleukin-6,IL-6)水平,以及皮瓣组织中超氧化物歧化酶(superoxide dismutase,SOD)和丙二醛(malondialdehyde,MDA)水平。采用SPSS 20.0软件包对数据进行t检验。结果 硝酸盐组皮瓣的存活面积显著高于对照组(P<0.05)。H-E染色显示,硝酸盐明显减轻了皮瓣的组织学损伤。硝酸钠显著增加了血清中硝酸盐和亚硝酸盐水平(P<0.05),并显著下调血清中TNF-a和IL-6水平(P<0.05)。此外,硝酸盐组皮瓣组织内MDA表达显著减少(P<0.05),SOD表达显著增加(P<0.05)。结论 口服硝酸盐可通过调控皮瓣的氧化应激和炎症反应保护皮瓣。 相似文献
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尽管嵌合抗原受体(CAR)T细胞治疗在血液系统恶性肿瘤患者中取得了显著的临床疗效,但需要进一步优化。脂质纳米粒(LNP)-信使核糖核酸(mRNA)递送系统作为一种非病毒性基因载体运用于CAR-T细胞治疗研究中,一方面通过LNP将密封蛋白-6 mRNA靶向递送至抗原提呈细胞,从而实现抗原提呈细胞辅助性增强密封蛋白-6靶向的CAR-T细胞的功能,以进一步诱导对实体瘤的清除;另一方面,通过LNP将成纤维细胞激活蛋白(FAP)CARmRNA靶向递送至T细胞,实现体内FAP靶向的CAR-T细胞的制备,以通过阻断心脏纤维化过程达到治疗急性心肌损伤的目的。在CAR-T细胞研究和治疗中,LNP-mRNA递送系统具有不与细胞基因组整合、价格便宜、毒副作用小及可修饰等优点,亦存在蛋白瞬时表达导致调控细胞功能的持久性不足及制备等方面的技术局限性。本文综述了LNP-mRNA递送系统及其在CAR-T细胞治疗中的应用研究。 相似文献
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目的探讨不同修复方法修复口腔颌面部肿瘤术后缺损的效果。方法选取口腔颌面部肿瘤根治术后缺损患者89例,根据最终选取的修复方案分为A组(n=49)和B组(n=40),A组给予股前外侧嵌合皮瓣修复,B组给予串联皮瓣修复。观察2组手术情况,采用华盛顿大学头颈肿瘤生活质量量表(UW-QOL)对患者术后生活质量进行评价,检测唾液中唾液酸(SA)及癌胚抗原(CEA)水平。结果A组手术时间、胃管拔除时间和经口进食时间分别为(6.30±1.19)h、(19.77±2.81)d和(20.32±2.19)d,明显少于B组(P<0.05);但A组皮瓣制作时间为(1.20±0.28)h,明显多于B组(P<0.05)。A组术后6个月UW-QOL量表中外观、吞咽、咀嚼、言语、肩功能、情绪评分分别为(63.29±4.54)分、(54.93±5.03)分、(47.12±6.02)分、(64.49±4.33)分、(82.20±5.43)分和(75.50±7.20)分,明显高于B组(P<0.05)。A组和B组术后6个月UW-QOL量表中疼痛、活动、娱乐、味觉、唾液及焦虑评分比较差异无统计学意义(P>0.05)。A组修复后1个月唾液中SA和CEA分别为(7.29±1.33)ng/dl和(50.04±16.62)ng/ml,明显低于B组(P<0.05)。A组血管危险发生率为2.04%,明显低于B组(P<0.05)。A组和B组感染、皮瓣坏死发生率差异比较无统计学意义(P>0.05)。结论相比较串联皮瓣修复,股前外侧嵌合皮瓣修复口腔颌面部肿瘤根治术后缺损有较好的效果,可以改善患者生活质量。 相似文献
37.
心血管系统疾病是威胁居民健康的重要因素之一,居各种死因首位。因此,对人体心血管健康状况的监测和诊断尤为重要。相较于传统的外周动脉压,中心动脉压(central arterial pressure, CAP)与许多心血管事件发生有更高的相关性,通过测量CAP可以更加准确地反映人体血压的真实情况,并为诊断和疾病的预防提供重要依据。因此,实现高精度、高泛化能力、低成本的CAP无创测量方法一直是该领域的研究重点。结合国内外的相关文献,总结CAP测量现状,从参数测量与波形测量两个方面介绍相关的研究进展,并探讨现有方法的特点以及未来的发展方向。 相似文献
38.
Joël Greffier Djamel Dabli Aymeric Hamard Philippe Akessoul Asmaa Belaouni Jean-Paul Beregi Julien Frandon 《Diagnostic and interventional imaging》2021,102(7-8):405-412
PurposeTo assess the impact of dose reduction and the use of an advanced modeled iterative reconstruction algorithm (ADMIRE) on image quality in low-energy monochromatic images from a dual-source dual energy computed tomography CT (DSCT) platform.Materials and methodsAcquisitions on an image-quality phantom were performed using DSCT equipment with 100/Sn150 kVp for four dose levels (CTDIvol: 20/11/8/5mGy). Raw data were reconstructed for six energy levels (40/50/60/70/80/100 keV) using filtered back projection and two levels of ADMIRE (A3/A5). Noise power spectrum (NPS) and task-based transfer function (TTF) were calculated on virtual monoenergetic images (VMIs). Detectability index (d′) was computed to model the detection task of two enhanced iodine lesions as function of keV.ResultsNoise-magnitude was significantly reduced between 40 to 70 keV by ?56 ± 0% (SD) (range: ?56%–?55%) with FBP; ?56 ± 0% (SD) (?56%–?56%) with A3; and ?57 ± 1% (SD) (range: ?57%–?56%) with A5. The average spatial frequency of the NPS peaked at 70 keV and decreased as ADMIRE level increased. TTF values at 50% were greatest at 40 keV and shifted towards lower frequencies as the keV increased. The detectability of both lesions increased with increasing dose level and ADMIRE level. For the simulated lesion with iodine at 2 mg/mL, d’ values peaked at 70 keV for all reconstruction types, except for A3 at 20 mGy and A5 at 11 and 20 mGy, where d’ peaked at 60 keV. For the other simulated lesion, d’ values were highest at 40 keV and decreased beyond.ConclusionAt low keV on VMIs, this study confirms that iterative reconstruction reduces the noise magnitude, improves the spatial resolution and increases the detectability of enhanced iodine lesions. 相似文献
39.
Ming-Li Chen Shuo-Hsuan Wang James Cheng-Chung Wei Hei-Tung Yip Yao-Min Hung Renin Chang 《The oncologist》2021,26(3):e473-e483
Background
This study investigated the correlation between a history of human papillomavirus (HPV) infection and skin cancer risk.Materials and Methods
The study cohort comprised 26,919 patients with newly diagnosed HPV infection between 2000 and 2012; with the use of computer-generated numbers, patients without previous HPV infection were randomly selected as the comparison cohort. The patients in the HPV infection cohort were matched to comparison individuals at a 1:4 ratio by demographic characteristics and comorbidities. All study individuals were followed up until they developed skin cancer, withdrew from the National Health Insurance program, were lost to follow-up, or until the end of 2013. The primary outcome was subsequent skin cancer development. Cox proportional hazards regression analysis was used to analyze the risk of skin cancer with hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort.Results
The adjusted HR of skin cancer for patients with HPV relative to controls was 2.45 after adjusting sex, age and comorbidities. (95% CI, 1.44–4.18, p < .01). The subgroup analysis indicated that a patient with HPV infection had a significantly greater risk of skin cancer if they were aged >40 years. Notably, a risk of skin cancer was found in the group diagnosed with HPV within the first 5 years after the index date (adjusted HR, 3.12; with 95% CI, 1.58–5.54). Sensitivity analysis by propensity score, matching with balanced sex, age, and comorbidities, showed consistent results.Conclusion
A history of HPV infection is associated with the development of subsequent skin cancer in Taiwanese subjects, and the risk wanes 5 years later.Implications for Practice
In this Taiwan nationwide cohort study, there was a 2.45-fold increased risk of developing new-onset skin cancers for patients with incident human papillomavirus (HPV) infection, compared with the matched controls. Furthermore, the risk was noticeably significant among patients aged >40 years. A prominent risk of skin cancers was found in the group diagnosed with HPV within the first 5 years after the index date in this study. The results of this analysis may raise consensus on the effect of HPV infection on the risk of skin cancers. Clinicians are encouraged to implement prudently on the differential diagnosis of skin cancers and HPV prevention and treatment, especially in older patients.40.