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1.
目的 探究MicroRNA-4516(miR-4516)、MicroRNA-198(miR-198)在视网膜母细胞瘤(RB)Y79细胞中的表达及其临床意义。方法 收集2018年3月至2021年3月行眼球摘除术治疗的35例RB患儿的肿瘤组织及30例正常视网膜组织标本,比较肿瘤组织、正常视网膜组织和Y79细胞中miR-4516、miR-198的表达水平。脂质体转染法建立miR-4516、miR-198过表达组(miR-4516-mimics组、miR-198-mimics组)、抑制组(miR-4516-inhibitor组、miR-198-inhibitor组)和对照组(miR-4516-NC组、miR-198-NC组)。CCK-8法检测转染24 h、48 h和72 h后各组细胞的增殖活性;实时荧光定量PCR(qRT-PCR)法检测转染48 h后各组细胞miR-4516、miR-198表达水平;流式细胞术检测各组细胞凋亡率;Western blot法检测各组细胞P53、Bcl-2蛋白表达。结果 肿瘤组织及Y79细胞中miR-4516的表达水平均高于正常视网膜组织,miR-198则相反,差异均有统计学意义(均为P<0.05)。细胞转染48 h后,miR-4516、miR-198分别在各自的inhibitor组、NC组和mimics组细胞内相对表达量逐渐升高(均为P<0.05)。转染后24 h、48 h、72 h,各组细胞增殖活性均逐渐升高,差异均有统计学意义(均为P<0.05),且同一时间点各组的细胞增殖活性比较,miR-4516-mimics组>miR-4516-NC组>miR-4516-inhibitor组,miR-198-inhibitor组>miR-198-NC组>miR-198-mimics组,差异均有统计学意义(均为P<0.05)。转染后48 h,各组细胞凋亡率比较,miR-4516-inhibitor组>miR-4516-NC组>miR-4516-mimics组,miR-198-mimics组>miR-198-NC组>miR-198-inhibitor组,差异均有统计学意义(均为P<0.05)。P53蛋白在miR-4516-mimics组、miR-4516-NC组和miR-4516-inhibitor组中表达逐渐升高,Bcl-2蛋白表达逐渐降低,差异均有统计学意义(均为P<0.05);P53蛋白在miR-198-mimics组、miR-198-NC组、miR-198-inhibitor组中表达逐渐降低,Bcl-2蛋白表达逐渐升高,差异均有统计学意义(均为P<0.05)。结论 miR-4516在RB肿瘤组织及Y79细胞中呈高表达状态,miR-198呈低表达状态;miR-4516可促进Y79细胞增殖,抑制其凋亡,miR-198可抑制Y79细胞增殖,二者有望成为RB的新的肿瘤标志物。  相似文献   
2.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals.  相似文献   
3.
目的探讨白细胞介素37b重组蛋白(rmIL-37b)通过调节CD39/ATP轴抑制树突状细胞(DC)诱导类风湿性关节炎(RA)大鼠炎症反应的机制。方法将SD大鼠随机分为空白对照组(CTL)、CIA模型组、rmIL-37b 5μg/kg组、rmIL-37b 10μg/kg组,每组各10只。除了空白对照组外,其余大鼠采用含有卡介苗的完全弗氏佐剂和牛Ⅱ型胶原混合乳液免疫刺激,建立CIA模型。确定建模成功当天(D0),rmIL-37b组分别尾静脉注射5μg/kg、10μg/kg rmIL-37b;CTL组和CIA模型组注射相同体积的(1 ml/kg)生理盐水,连续给药15 d。免疫组化法检测滑膜组织Nod样受体蛋白3(NRPL3)炎症小体的表达,流式细胞术检测DC表型,另外试剂盒检测血清三磷酸腺苷(ATP)和免疫学指标。结果与CIA模型组相比,rmIL-37b 10μg/kg组大鼠足容积、AI值、NLRP3炎症小体表达量、血清ATP、IL-1β、IL-18、肿瘤坏死因子α(TNF-α)、抗Ⅱ型胶原抗体亚型(anti-ColⅡ-IgG、anti-ColⅡ-IgG2a)水平均降低,同时DC表面CD...  相似文献   
4.
PurposeOptical coherence tomography angiography (OCTA) was utilized to examine changes in ocular surface squamous neoplasia (OSSN) vascular patterns over time in individuals treated with topical medical therapy.MethodsTen individuals with OSSN diagnosed by clinical examination and high resolution (HR)-optical coherence tomography (OCT) were recruited. All individuals received topical immuno- or chemotherapy. OCTA images were obtained and analyzed at three points: presentation, mid-treatment and tumor resolution. Tumor metrics including tumor area (TA), tumor volume (TV), tumor depth (TD), and total tumor density (TTD) were calculated. Vessel area density (VAD) was also quantified within the OSSN, the subepithelium under and adjacent to the OSSN and the subepithelium of the uninvolved, contralateral eye. Vascular network changes were also subjectively evaluated.ResultsTA, TV, TD and TTD all significantly decreased with time (p < 0.001). The mean VAD within the OSSN significantly decreased (p < 0.001) between visits (presentation: 26.52 ± 6.8%, mid-treatment: 7.19 ± 5.88%, tumor resolution: 0.11 ± 0.34%). The mean subepithelial VAD under the OSSN also decreased with time (23.22 ± 11.03%, 20.99 ± 5.99% and 19.58 ± 7.08%), and after resolution the sub-tumor VAD (19.58 ± 7.08%) was comparable to the subepithelial VAD in the contralateral eye (15.47 ± 4.37%, p > 0.05). The mean VAD in the subepithelium adjacent to the OSSN increased with treatment, then decreased significantly between mid-treatment and resolution (23.26 ± 4.54, 28.30 ± 7.43% and 21.68 ± 6.10%, p = 0.009). Qualitatively, the tumor subepithelial vascular network was complex and dense but with tumor resolution appeared less tortuous and similar to the uninvolved eye.ConclusionOCTA provided insight into the pathophysiology of tumor angiogenesis, showing decreased vascular density and normalization of vascular networks associated with tumor resolution.  相似文献   
5.
《Vaccine》2022,40(13):1924-1927
High vaccine reactogenicities may reflect stronger immune responses, but the epidemiological evidence for coronavirus disease 2019 (COVID-19) vaccines is sparse and inconsistent. We observed that a fever of ≥38℃ after two doses of the BNT162b2 vaccine was associated with higher severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike IgG titers.  相似文献   
6.
BackgroundIn order to avoid excessive treatment of thyroid nodules in the clinic, it is necessary to find a simple and practical analysis method to comprehensively and accurately reflect benign or malignant thyroid nodules. This study aimed to construct and validate a comprehensive and reliable network-based predictive model using a variety of imaging and laboratory criteria for thyroid nodules to stratify the risk of malignancy prior to surgery.MethodsWe retrospectively analyzed data from patients who underwent surgical treatment for thyroid nodules at the Thyroid and Breast Diagnosis and Treatment Center of Weifang Hospital of Traditional Chinese Medicine between January 2018 and December 2020. Binary logical regression analysis was performed to predict whether nodules were malignant or benign. The developmental dataset included 457 patients (January 2018–December 2020). The validation set included separate data points (n = 225, January 2018–December 2020).ResultsIn this study, criteria that showed significant predictive value for malignant nodules included TI-RADS: 4b (p = 0.065); Bethesda IV, Bethesda V, Bethesda VI (P < 0.0001); BRAFV600E mutation (P < 0.0001); Calcitonin>5 pg/ml (p = 0.0037); and FNA-Tg>30 ng/ml (p = 0.0003). A 10-grade risk scoring system was developed. The risk of malignancy risk ranged from 2.06% to 100% and was positively associated with increasing risk grade. The areas under the receiver-operating characteristic curve of the development and validation sets were 0.972 and 0.946, respectively.ConclusionA simple, comprehensive and reliable web-based predictive model was designed using a variety of imaging and laboratory criteria to stratify thyroid nodules by probability of malignancy.  相似文献   
7.
Background and aimsIntermittent fasting reduces risk of interrelated cardiometabolic diseases, including type 2 diabetes and heart failure (HF). Previously, we reported that intermittent fasting reduced homeostasis model assessment of insulin resistance (HOMA-IR) and Metabolic Syndrome Score (MSS) in the WONDERFUL Trial. Galectin-3 may act to reduce insulin resistance. This post hoc evaluation assessed whether intermittent fasting increased galectin-3.Methods and resultsThe WONDERFUL Trial enrolled adults ages 21–70 years with ≥1 metabolic syndrome features or type 2 diabetes who were not taking anti-diabetic medication, were free of statins, and had elevated LDL-C. Subjects were randomized to water-only 24-h intermittent fasting conducted twice-per-week for 4 weeks and once-per-week for 22 weeks or to a parallel control arm with ad libitum energy intake. The study evaluated 26-week change scores of galectin-3 and other biomarkers. Overall, n = 67 subjects (intermittent fasting: n = 36; control: n = 31) completed the trial and had galectin-3 results. At 26-weeks, the galectin-3 change score was increased by intermittent fasting (median: 0.793 ng/mL, IQR: ?0.538, 2.245) versus control (median: ?0.332 ng/mL, IQR: ?0.992, 0.776; p = 0.021). Galectin-3 changes correlated inversely with 26-week change scores of HOMA-IR (r = ?0.288, p = 0.018) and MSS (r = ?0.238, p = 0.052). Other HF biomarkers were unchanged by fasting.ConclusionA 24-h water-only intermittent fasting regimen increased galectin-3. The fasting-triggered galectin-3 elevation was inversely correlated with declines in HOMA-IR and MSS. This may be an evolutionary adaptive survival response that protects human health by modifying disease risks, including by reducing inflammation and insulin resistance.Trial registrationClinicaltrials.gov, NCT02770313 (registered on May 12, 2016; first subject enrolled: November 30, 2016; final subject's 26-week study visit: February 19, 2020).  相似文献   
8.
ObjectiveTo analyze the efficacy and safety of photodynamic therapy (PDT) on postmenopausal women with persistent human papillomavirus (HPV) infection with or without low-grade cervical and vaginal intraepithelial neoplasia (CIN1 and VaIN1).Materials and methodsThe clinicopathological and follow-up data of 86 postmenopausal women with HPV infection (35 cases with chronic cervicitis and 51 cases with CIN1/VaIN1) were collected. All the women in this group met these criteria: menopausal time ≥ 1 year, HPV infection time ≥ 2 years, colposcopy and pathological diagnosis of biopsy ≤ CIN1/VaIN1 before PDT treatment, and 5-aminolaevulinic acid (5-ALA) as photosensitizer treating for 6 times with a week interval. The above patients were followed up 6 months and 12 months after PDT treatment, and the follow-up contents included HPV typing, cytology, colposcopy and pathological examinations. HPV negative conversion rate and lesion remission rate are the evaluation indicators of treatment efficacy. In addition, we also assessed the safety of PDT treatment.ResultsAt 12-month follow-up, the overall HPV clearance rate was 60% (45/75), of which the negative conversion rate of 16/18 HPV was 41.38% (12/29), and non-16/18 HPV was 71.74% (33/46) (p = 0.009). In patients without lesions, the HPV clearance rate was 51.72% (15/29), while in patients with CIN1/VaIN1 (n = 46), the HPV complete remission rate and lesion regression rate were 65.22% (30/46) and 89.13% (41/46), respectively. In addition, the clearance rate of HPV in lesion regression group was significantly higher than that in lesion persistence/progression group (0.00% vs. 73.17%, p = 0.003). The adverse reactions after PDT treatment were mild, mainly manifested as increased vaginal secretions or burning/tingling.ConclusionsPhotodynamic therapy can significantly enhance the elimination rate of persistent HPV infection in postmenopausal women and reduce the progression of CIN1/VaIN1. It could be an effective conservative treatment for persistent HPV infection and CIN1/VaIN1 in postmenopausal women.  相似文献   
9.
《Vaccine》2022,40(6):934-944
Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity. In naïve mice, both Ad26.RSV.preF and preF protein induced humoral responses, whereas cellular responses were only elicited by Ad26.RSV.preF. In RSV pre-exposed mice, a single dose of either vaccine induced cellular responses and strong humoral responses. Ad26-induced RSV-specific cellular immune responses were detected systemically and locally in the lungs. Both vaccines showed protective efficacy in the cotton rat model, but Ad26.RSV.preF conferred protection at lower virus neutralizing titers in comparison to RSV preF protein. Factors that may contribute to the protective capacity of Ad26.RSV.preF elicited immunity are the induced IgG2a antibodies that are able to engage Fcγ receptors mediating Antibody Dependent Cellular Cytotoxicity (ADCC), and the induction of systemic and lung resident RSV specific CD8 + T cells. These data demonstrate qualitative improvement of immune responses elicited by an adenoviral vector based vaccine encoding the RSV preF antigen compared to the subunit vaccine in small animal models which may inform RSV vaccine development.  相似文献   
10.
 目的 探讨重组人干扰素α1b(rhIFN-α1b)通过调控叉状头/翅膀状螺旋转录因子3(Foxp3)表达对传染性单核细胞增多症(IM)患儿机体免疫功能的调节作用。方法 选取2019年3月-2020年3月某院儿科收治的98例IM患儿,使用简单随机数字表法将其随机分成干扰素组(n=49)和更昔洛韦组(n=49)。干扰素组采取注射用rhIFN-α1b雾化吸入治疗,更昔洛韦组予以注射用更昔洛韦静脉滴注治疗,疗程均为7 d。观察两组患儿的临床疗效及安全性,并比较治疗前后两组患儿外周血单个核细胞(PBMC)中Foxp3信使核糖核酸(Foxp3 mRNA)表达水平、机体免疫功能、血清相关细胞因子的水平。结果 干扰素组总有效率和血清EB病毒脱氧核糖核酸(EBV-DNA)阴转率[87.8%(43/49)、89.8%(44/49)]均高于更昔洛韦组[71.4%(35/49)、73.5%(36/49),均P<0.05]。与更昔洛韦组相比,干扰素组患儿在热程、咽峡炎好转时间及异常实验室指标(白细胞计数、异型淋巴细胞比例、丙氨酸氨基转移酶和肌酸激酶同工酶)复常时间和住院时间均缩短(均P<0.05)。两组患儿治疗后外周血CD3+、CD8+水平和血清肿瘤坏死因子-α、白介素(IL)-6水平较本组治疗前均下降(均P<0.05),外周血CD4+水平、CD4+/CD8+比值及PBMC中Foxp3 mRNA表达水平和血清免疫球蛋白(Ig)IA、IgG、IL-2浓度均高于本组治疗前(均P<0.05);但干扰素组患儿改善均更明显(均P<0.05)。干扰素组不良反应率低于对照组(4.1% VS 20.4%,P<0.05)。结论 rhIFN-α1b可能通过上调IM患儿PBMC中Foxp3 mRNA的表达水平,以纠正患儿异常的细胞免疫功能,提高其体液免疫水平。  相似文献   
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