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1.
目的 探讨事件相关电位P300在颅脑损伤患者认知功能障碍评定中的应用价值。方法 选取2021年1月-9月在绵阳市第三人民医院神经外科保守治疗、并符合诊断标准的颅脑损伤患者36例作为研究组,同期在医院其他患者家属和护工中招募健康对照组共36名。采用Oddball范式对受试者进行事件相关电位P300检测,采用蒙特利尔认知评估量表(MoCA)和简易精神状态评价量表(MMSE)评定受试者的认知功能。比较两组P300的潜伏期、波幅以及MoCA和MMSE评分,比较P300潜伏期、MoCA和MMSE对颅脑损伤患者认知功能障碍的检出率。结果 研究组MoCA和MMSE评分均低于对照组[(18.08±4.29)分vs.(27.36±1.20)分,(22.53±3.54)分vs.(28.11±1.09)分,t=-12.510、-9.041,P均<0.05];研究组P300潜伏期高于对照组[(406.08±26.95)ms vs.(367.08±22.50)ms,t=6.665,P<0.05],波幅低于对照组[(7.76±0.90)μV vs.(9.87±0.99)μV,t=-9.459,P<0.05]。在研究组中,P300潜伏期阳性检出率和MoCA对认知功能障碍的检出率均高于MMSE对认知功能障碍的检出率(χ2=5.675、7.604,P均<0.05)。结论 事件相关电位P300或许可作为评估颅脑损伤患者认知功能障碍的客观临床指标。  相似文献   
2.
目的 探讨益气活血通络方对糖尿病神经病理性疼痛(diabetic neuropathic pain,DNP)的影响及其作用机制。方法 高脂喂养大鼠4周后,35 mg/kg链脲佐菌素(streptozotocin,STZ)腹腔注射复制2型糖尿病大鼠模型,通过观测大鼠机械痛阈和热缩足反应时间作为判定DNP模型复制成功的标准。将DNP大鼠随机分为模型组,益气活血通络方高、中、低剂量组和阳性对照组(甲钴胺),另设空白对照组。Western blot法和免疫荧光双标检测脊髓中补体受体- 3的单克隆抗体(monoclonal antibody of complement receptor type 3,OX42)和P2X7(purinergic 2X7)的表达水平;ELISA法检测血清肿瘤坏死因子- α(tumor necrosis factor- α,TNF- α)、白细胞介素- 1β(interleukin- 1β,IL- 1β)和趋化因子配体3(CC- chemokine ligand 3,CCL3)水平。结果 益气活血通络方干预后,DNP大鼠的机械痛阈和热缩足反应时间均得到显著的改善;大鼠血清TNF- α、IL- 1β和CCL3水平显著降低(P<0.05);脊髓组织中OX42和P2X7表达水平均显著降低(P<0.05)。结论 益气活血通络方对DNP大鼠具有显著的治疗作用,其作用机制可能是通过抑制脊髓小胶质细胞活性,调节P2X7的表达,从而减轻神经炎症反应。  相似文献   
3.
4.
目的 观察治伤巴布剂对急性软组织损伤(acute soft tissue injury, ASTI)模型p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)、丝/苏氨酸蛋白激酶(AKT)信号通路的影响,探讨治伤巴布剂干预ASTI的可能作用机制。方法 将40只雄性SD大鼠按照随机数字表法分为正常对照组、模型对照组、治伤巴布剂组、p38MAPK信号通路抑制剂组、AKT信号通路抑制剂组,每组8只。除正常对照组外,其余四组均予以左侧后肢小腿ASTI造模。造模成功后,治伤巴布剂组于标记部位立即予治伤巴布剂(修剪成1.5x3cm大小)外敷,并用胶布固定;其余四组均予等剂量赋形剂(修剪成1.5×3 cm大小)外敷处理,胶布固定;持续外敷,共持续24 h。p38MAPK信号通路抑制剂组在造模前30 min予腹腔注射p38MAPK信号通路抑制剂SB203580(400 μg/kg/天)1次;AKT信号通路抑制剂组在造模前30 min予腹腔注射AKT信号通路抑制剂perifosine(20 mg/kg/天)1次。分别于0(造模前)、2h、4h、8h、12h、24h测量受伤小腿肌肉处的周长,并计算肌肉肿胀率(muscle swelling rate,MSR)。24 h药物干预结束后,采用颈椎脱臼法处死大鼠。后将左侧后肢小腿损伤中心部位进行取材,分成三份。一部分用于观察组织病理学形态变化;一部分用于逆转录聚合酶链反应(RT-PCR)检测核因子-κB(nuclear factor kappa-B,NF-κB)p65 mRNA、肿瘤坏死因子-α(TNF-α)mRNA、白细胞介素-1β(IL-1β)mRNA表达水平;剩下部分用酶联免疫吸附试验(ELISA)法检测骨骼肌组织TNF-α、IL-1β含量水平及蛋白质免疫印迹(Western-blot)法测定p38MAPK、AKT、NF-κB p65、核因子抑制蛋白α(inhibitor kappa B alpha, IκBα)表达水平。结果 与正常对照组相比,模型对照组MSR显著增加(P<0.01);病理形态学上,骨骼肌组织可见大面积肌细胞排列紊乱,肌细胞变性坏死,间质内可见红细胞聚集及大量炎症细胞浸润;骨骼肌组织TNF-α、IL-1β含量水平显著升高(P<0.01);磷酸化p38MAPK(p-p38)/总p38MAPK(t-p38),磷酸化-AKT(p-AKT)/总-AKT(t-AKT)明显升高(P<0.01),NF-κB p65及NF-κB p65mRNA表达水平明显升高(P<0.01)。与模型对照组相比,治伤巴布剂组MSR在治疗第8 h、12 h、24 h显著下降(P<0.01),且在治疗第24 h,其MSR较p38MAPK、AKT信号通路抑制剂组下降更明显(P<0.05);病理学评分显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组下降更显著(P<0.05);骨骼肌组织TNF-α、IL-1β含量水平明显下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组更显著(P<0.05);p-p38/t-p38及p-AKT/t-AKT明显下降(P<0.01),NF-κB p65及NF-κB p65 mRNA表达水平显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组在降低NF-κB p65及NF-κB p65 mRNA相对表达值方面更显著(P<0.01)。结论 治伤巴布剂可能同时对p38MAPK、AKT信号通路产生了一定的抑制作用,引起NF-κB活性下调,NF-κB p65蛋白的表达下调,进而引起骨骼肌组织TNF-α、IL-1β炎性细胞因子含量水平下调,减轻ASTI炎症反应,从而改善ASTI。  相似文献   
5.
We aimed to explore the correlation between P27 expression and Helicobacter pylori (H. pylori) infection in gastric cancer, so as to provide evidence for understanding the pathogenesis of gastric cancer caused by H. pylori infection. A total of 82 samples of gastric cancer tissues and 56 samples of tumor-adjacent normal tissues collected from the gastrectomy were enrolled in this study. Then, 14C-urease breathing test was carried out to evaluate the infection of H. pylori in gastric cancer tissues, the expression of P27 in the tissue samples was detected by the immunohistochemistry staining, and the correlation between the H. pylori infection and P27 expression in gastric cancer was analyzed. Of 82 gastric cancer patients, there were 53 patients with H. pylori infection (64.63%). Among the patients with highly or moderately differentiated gastric cancer, the expression of P27 was much higher than that of patients with poorly differentiated gastric cancer (p < 0.01). Besides, comparison of the P27 expression between males and females, among different age groups, tumor sizes, TNM stages, tumor infiltration degrees, or lymph node metastasis, showed no significant differences (p > 0.05). Analysis of the correlation revealed that P27 expression was negatively correlated with the infection of H. pylori (p < 0.01). Multifactorial logistics regression analysis indicated that tumor differentiation was a risk factor of P27-positive expression in gastric cancer tissues (p < 0.01). In addition, P27 expression in the gastric cancer tissues was lower than that in the tumor-adjacent normal tissues (p < 0.01). In gastric cancer patients, expression of P27 is correlated with H. pylori infection which, via downregulating P27, can cause the cancerization of gastric mucosa, and P27, for its role in the development and progression of gastric cancer, is a potential auxiliary indicator for clinical diagnosis whether gastric cancer is complicated with H. pylori infection. So, P27 is a key indicator for diagnosis, treatment, and prognostic evaluation of disease in the advanced stage.  相似文献   
6.
探究益气祛痰解毒方对非小细胞肺癌(non-small cell lung cancers,NSCLC)细胞的抑制作用和相关分子机制。方法 构建FRMD6(FERM domain-containing protein 6, FRMD6)敲低PC9细胞株。将PC9细胞分为对照组,shNC组,shFRMD6组,益气祛痰解毒方+shNC组,益气祛痰解毒方+shFRMD6组。采用实时定量PCR(qRT-PCR)检测各组PC9细胞的FRMD6表达水平变化;应用CCK-8法检测各组PC9细胞增殖率;采用Annexin V-FITC/PI法检测试各组PC9细胞凋亡情况;利用Transwell实验检测各组PC9细胞侵袭能力;利用Western blot检测各组FRMD6, c-MET, p-PI3K, PI3K, p-Akt和Akt蛋白表达的变化。结果 CCK8检测结果表明,与对照组相比,益气祛痰解毒方对PC9细胞增殖具有显著抑制效果(P < 0.05);qRT-PCR和Western blot结果显示,发现益气祛痰解毒方可以上调FRMD6表达。进一步进行qRT-PCR和Western blot结果表明FRMD6敲低PC9细胞株构建成功;益气祛痰解毒方处理能够抑制PC9细胞增殖、侵袭,并促进细胞凋亡;同时,与shNC组相比,益气祛痰解毒方+shNC组均可显著抑制PC9细胞增殖、侵袭并促进细胞凋亡(P < 0.05)。Western blot结果发现,益气祛痰解毒方+shNC组相较于shNC组的c-MET、p-PI3K和p-Akt表达明显降低,说明使用益气祛痰解毒方处理可抑制c-MET/PI3K/AKT通路;此外,与shFRMD6组相比,益气祛痰解毒方+shFRMD6组c-MET、p-PI3K和p-Akt表达显著下调,敲低FRMD6表达会显著减弱益气祛痰解毒方对c-MET/PI3K/AKT通路的抑制作用。结论 益气祛痰解毒方能够抑制肺癌PC9细胞增殖、降低侵袭能力和促进细胞凋亡,其分子机制可能通过FRMD6调控c-MET/PI3K/AKT通路来实现。  相似文献   
7.
In the field of drug development, technology for producing human metabolites at a low cost is required. In this study, we explored the possibility of using prokaryotic water-soluble cytochrome P450 (CYP) to produce human metabolites. Streptomyces griseolus CYP105A1 metabolizes various non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, meclofenamic acid, and ibuprofen. CYP105A1 showed 4′-hydroxylation activity towards diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, and meclofenamic acid. It should be noted that this reaction specificity was similar to that of human CYP2C9. In the case of mefenamic acid, another metabolite, 3′-hydroxymethyl mefenamic acid, was detected as a major metabolite. Substitution of Arg at position 73 with Ala in CYP105A1 dramatically reduced the hydroxylation activity toward diclofenac, flufenamic acid, and ibuprofen, indicating that Arg73 is essential for the hydroxylation of these substrates. In contrast, substitution of Arg84 with Ala remarkably increased the hydroxylation activity towards diclofenac, mefenamic acid, and flufenamic acid. Recombinant Rhodococcus erythrocyte cells expressing the CYP105A1 variant R84A/M239A showed complete conversion of diclofenac into 4′-hydroxydiclofenac. These results suggest the usefulness of recombinant R. erythropolis cells expressing actinomycete CYP, such as CYP105A1, for the production of human drug metabolites.  相似文献   
8.
能量代谢每时每刻都伴随着物质代谢在生命体内发生。生物通过利用物质代谢产生的高能磷酸化合物以维持各项生命功能的运转,不同状态下的细胞通过利用各种物质通过不同的通路进行不同的代谢方式。促分裂原活化的蛋白激酶(MAPK)通路作为生命体里广泛存在的一类信号蛋白,影响着细胞、生物体的生命活动。MAPK通路在能量代谢的各个环节起着非常重要的作用。通过研究MAPK通路中的胞外信号调节激酶(ERK)通路、Jun激酶(JNK)通路、P38通路均与能量代谢有关的蛋白、靶点、关键酶、转运体,与三大营养物质能量代谢相结合,从而为能量代谢相关的细胞功能进一步研究铺垫,并为今后治疗肿瘤性疾病、感染性疾病、代谢性疾病等提供新思路。  相似文献   
9.
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   
10.
The intestinal mucosa is a highly compartmentalized structure that forms a direct barrier between the host intestine and the environment, and its dysfunction could result in a serious disease. As T cells, which are important components of the mucosal immune system, interact with gut microbiota and maintain intestinal homeostasis, they may be involved in the process of intestinal barrier dysfunction. P2X7 receptor (P2X7R), a member of the P2X receptors family, mediates the effects of extracellular adenosine triphosphate and is expressed by most innate or adaptive immune cells, including T cells. Current evidence has demonstrated that P2X7R is involved in inflammation and mediates the survival and differentiation of T lymphocytes, indicating its potential role in the regulation of T cell function. In this review, we summarize the available research about the regulatory role and mechanism of P2X7R on the intestinal mucosa-derived T cells in the setting of intestinal barrier dysfunction.  相似文献   
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