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991.
Fumonisin B1 (FB1) is a mycotoxin produced by microscopic fungi (mostly Fusarium species), which may infect our major crops. The toxin inhibits the development of these plants and may also have harmful effects on animals and humans consuming the infected crops.FB1 inhibits sphingolipid biosynthesis which leads to altered membrane characteristics and consequently, altered cellular functions. There are some indications that the toxin has inhibitory effects on neuronal activity in case of repeated consumption, presumably due to sphingolipid depletion. However, according to new literature data, FB1 may have acute excitatory neural effects, too, via different mechanisms of action. Therefore, in the present study, we addressed the neuronal network effects of FB1 following acute treatment, using different electrophysiological techniques in vitro and in vivo.Acute treatments with FB1 (10–100 μM) were carried out on brain slices, tissue cultures and live animals. After direct treatment of samples, electrically evoked or spontaneous field potentials were examined in the hippocampus and the neocortex of rat brain slices and in hippocampal cell cultures. In the hippocampus, a short-term increase in the excitability of neuronal networks and individual cells was observed in response to FB1 treatment. In some cases, the initially enhanced excitation was reversed presumably due to overactivation of neuronal networks. Normal spontaneous activity was found to be stimulated in hippocampal cell cultures. Seizure susceptibility was not affected in the neocortex of brain slices.For the verification of the results caused by direct treatment, effects of systemic administration of FB1 (7.5 mg/kg, i.p.) were also examined. Evoked field potentials recorded in vivo from the somatosensory cortex and cell activation measured by the c-fos technique in hippocampus and somatosensory cortex were analyzed. However, the hippocampal and cortical stimulatory effect detected in vitro could not be demonstrated by these in vivo assays.Altogether, the toxin enhanced the basic excitability of neurons and neuronal networks after direct treatment but there were no effects on the given brain areas after systemic treatment in vivo. Based on the observed in vitro FB1 effects and the lack of data on the penetration of FB1 across the blood-brain barrier, we assume that in vivo consequences of FB1 administration can be more prominent in case of perturbed blood-brain barrier functions. 相似文献
992.
《Brain & development》2020,42(3):264-269
ObjectiveSome pediatric patients with autoimmune encephalitis (AE) experience sequelae in spite of immunotherapy. In this study, we aimed to evaluate the association of serum matrix metallopeptidase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels with the neurological prognosis of AE.MethodsWe retrospectively included 13 patients with AE who had been referred to Saitama Children’s Medical Center from February 2011 to May 2019. We compared serum MMP-9 levels, TIMP-1 levels, and MMP-9/TIMP-1 ratio in the acute period (within 30 days from the onset of AE) and subacute period (30-day period following the acute period). We also compared these biomarker levels between patients with (group A) and without sequelae (group B). Sequelae were evaluated at discharge or the last visit.ResultsGroup A (median age, 7.8 years; range, 5.3–10.7 years) and group B (median age, 13.3 years; range, 11.1–15.4 years) had 6 patients each; 1 patient was excluded because the time of AE onset was unknown. In the acute period, there were no significant differences in MMP-9 levels, TIMP-1 levels, and MMP-9/TIMP-1 ratio between groups A and B. In the subacute period, serum MMP-9/TIMP-1 ratio was higher in group A than in group B (p < 0.01). There were no significant differences in MMP-9 and TIMP-1 levels between groups A and B.ConclusionsPatients with sequelae of AE showed a high MMP-9/TIMP-1 ratio in the subacute period. Our study demonstrates that elevation of serum MMP-9/TIMP-1 ratio in the subacute period may be a predictive factor of sequelae of AE. 相似文献
993.
《Revue neurologique》2020,176(3):180-188
ObjectivesTo determine the cost-effectiveness of stent retriever thrombectomy (SRT) added to standard of care (SOC) in large vessel occlusion (LVO) strokes, adopting the French societal perspective given the lack of published studies with such perspective.MethodsWe developed an hybrid model (decision tree until one year post-stroke followed by a Markov model from one year onward). The time horizon was 20 years. We calculated transition probabilities across the modified Rankin Scale (mRS) based on a published meta-analysis. The main outcome measure was quality adjusted life-years (QALYs) gained. Resources and input costs were derived from a literature search. We calculated the incremental cost-effectiveness ratio (ICER) expressed as cost/QALY. We used 1-way deterministic and probabilistic sensitivity analysis (PSA) to evaluate the model uncertainty.ResultsIn the base-case, adding SRT to SOC resulted in increased effectiveness of 0.73 QALY while total costs were reduced by 3,874€ (ICER of −5,400€/QALY). In the scenario analysis adopting the French healthcare system perspective, the ICER was 4,901€/QALY. Parameters the most influential were the relative risks of SRT over SOC for 90-days mortality and for 90-days mRS 0–2, and the time horizon. PSA showed the 95% confidence interval of the ICER was −21,324 to 4,591€/QALY, with SRT having 85.5% chance to be dominant and 100% to be cost-effective at a threshold of 50,000€/QALY.ConclusionSRT was dominant from a French societal perspective, from 9 years post-stroke onwards. Cost-effectiveness of SRT added to SOC becomes undisputable with evidences from payer and societal viewpoints. 相似文献
994.
目的:探索分泌PD-1 scFv的CAR-T细胞对胃癌的抗瘤功效。方法:选择EGFR作为CAR-T细胞的靶标,构建二代EGFR-CAR-T细胞(EGFR BB-z)和分泌PD-1 scFv的四代EGFR-CAR-T细胞(EGFR BB-z/E30),通过体外激活以及靶细胞长期刺激检测其抗肿瘤活性,通过胃癌移植瘤小鼠模型检测其肿瘤抑制能力。结果:胃癌组织及细胞均高表达EGFR(均P<0.01)。通过慢病毒感染的方式成功获得EGFR BB-z和EGFR BB-z/E30细胞。体外实验表明,与EGFR BB-z相比,EGFR BB-z/E30具有更长效的增殖能力及更强的肿瘤杀伤活性(均P<0.01)。体内实验显示了EGFR BB-z/E30在胃癌细胞皮下移植瘤模型和胃癌人源性肿瘤异种移植瘤(patient-derived tumor xenograft,PDX)模型中具有明显的肿瘤抑制能力(均P<0.01),并可显著增加肿瘤部位 T 细胞的浸润(P<0.01),减少 EGFR BB-z/E30 细胞表面 PD-1 的表达(P<0.01)和高分泌 IFN-γ 的水平(P<0.05)。结论:分泌PD-1 scFv的EGFR-CAR-T细胞EGFR BB-z/E30可对胃癌进展产生显著的抑制作用,为胃癌治疗提供一种潜在新策略。 相似文献
995.
Tatsuki Ueda Ayako Kumagai Shoichi Iriguchi Yutaka Yasui Tadayo Miyasaka Kengo Nakagoshi Kazuki Nakane Keigo Saito Mari Takahashi Aki Sasaki Shinsuke Yoshida Naoko Takasu Hiroshi Seno Yasushi Uemura Koji Tamada Tetsuya Nakatsura Shin Kaneko 《Cancer science》2020,111(5):1478-1490
The use of allogeneic, pluripotent stem‐cell‐derived immune cells for cancer immunotherapy has been the subject of recent clinical trials. In Japan, investigator‐initiated clinical trials will soon begin for ovarian cancer treatment using human leukocyte antigen (HLA)‐homozygous‐induced pluripotent stem cell (iPSC)‐derived anti–glypican‐3 (GPC3) chimeric antigen receptor (CAR)‐expressing natural killer/innate lymphoid cells (NK/ILC). Using pluripotent stem cells as the source for allogeneic immune cells facilitates stringent quality control of the final product, in terms of efficacy, safety and producibility. In this paper, we describe our methods for the stable, feeder‐free production of CAR‐expressing NK/ILC cells from CAR‐transduced iPSC with clinically relevant scale and materials. The average number of cells that could be differentiated from 1.8‐3.6 × 106 iPSC within 7 weeks was 1.8‐4.0 × 109. These cells showed stable CD45/CD7/CAR expression, effector functions of cytotoxicity and interferon gamma (IFN‐γ) production against GPC3‐expressing tumor cells. When the CAR‐NK/ILC cells were injected into a GPC3‐positive, ovarian‐tumor‐bearing, immunodeficient mouse model, we observed a significant therapeutic effect that prolonged the survival of the animals. When the cells were injected into immunodeficient mice during non–clinical safety tests, no acute systemic toxicity or tumorigenicity of the final product or residual iPSC was observed. In addition, our test results for the CAR‐NK/ILC cells generated with clinical manufacturing standards are encouraging, and these methods should accelerate the development of allogeneic pluripotent stem cell‐based immune cell cancer therapies. 相似文献
996.
Adrianna Klajmon Aldona Olechowska-Jarzb Dominika Salamon Agnieszka Sroka-Oleksiak Monika Brzychczy-Woch Tomasz Gosiewski 《Viruses》2022,14(1)
Diagnostics of the coronavirus disease 2019 (COVID-19) using molecular techniques from the collected respiratory swab specimens requires well-equipped laboratory and qualified personnel, also it needs several hours of waiting for results and is expensive. Antigen tests appear to be faster and cheaper but their sensitivity and specificity are debatable. The aim of this study was to compare a selected antigen test with quantitative polymerase chain reaction (qPCR) tests results. Nasopharyngeal swabs were collected from 192 patients with COVID-19 symptoms. All samples were tested using Vitassay qPCR SARS-CoV-2 kit and the Humasis COVID-19 Ag Test (MedSun) antigen immunochromatographic test simultaneously. Ultimately, 189 samples were tested; 3 samples were excluded due to errors in taking swabs. The qPCR and antigen test results were as follows: 47 positive and 142 negative, and 45 positive and 144 negative, respectively. Calculated sensitivity of 91.5% and specificity of 98.6% for the antigen test shows differences which are not statistically significant in comparison to qPCR. Our study showed that effectiveness of the antigen tests in rapid laboratory diagnostics is high enough to be an alternative and support for nucleic acid amplification tests (NAAT) in the virus replication phase in the course of COVID-19. 相似文献
997.
前脂肪细胞与蚕丝支架体外复合培养的实验研究 总被引:4,自引:0,他引:4
目的 观察蚕丝对前脂肪细胞吸附作用及蚕丝对前脂肪细胞形态和功能的影响,为脂肪组织工程支架选择提供依据.方法 从家蚕蚕茧中抽丝所得的原料蚕丝,经胰蛋白酶消化后与原料蚕丝分别制成三维支架,将前脂肪细胞制成细胞悬液接种在支架上,倒置显微镜和扫描电镜观察前脂肪细胞的吸附和生长.结果 在消化后的蚕丝三维支架可看见前脂肪细胞1~2 d后完全贴壁.培养3~7 d细胞生长增殖十分活跃,两周时,蚕丝支架网眼充满前脂肪细胞,扫描电镜见细胞与支架紧密贴附适度伸展并有基质分泌.结论 蚕丝对前脂肪细胞具有良好的吸附作用,并能维持前脂肪细胞正常形态和功能,蚕丝是前脂肪细胞立体培养时的天然支架. 相似文献
998.
Serafeim Chlapoutakis Vasiliki Epameinondas Georgakopoulou Nikolaos Trakas Georgios Kouvelos Petros Papalexis Christos Damaskos Pagona Sklapani Anastasios Grivas Panagiotis Gouveris Dimitrios Tryfonopoulos Alexandros Tzovaras Gerasimos Ardavanis-Loukeris Elissavet Grouzi Demetrios A. Spandidos Miltiadis Matsagkas 《Oncology Letters》2022,23(5)
Pulmonary embolism (PE), along with deep vein thrombosis, are collectively known as venous thromboembolism (VTE). Predisposing factors for PE include post-operative conditions, pregnancy, cancer and an advanced age; of note, a number of genetic mutations have been found to be associated with an increased risk of PE. The association between cancer and VTE is well-established, and cancer patients present a higher risk of a thrombotic event compared to the general population. In addition, PE is a significant cause of morbidity and mortality among cancer patients. The aim of the present study was to illustrate the clinical characteristics, laboratory findings, radiology features and outcomes of cancer patients who developed PE, collected from an anticancer hospital. For this purpose, adult cancer patients diagnosed with PE by imaging with computed tomography pulmonary angiography were enrolled. The following data were recorded: Demographics, comorbidities, type of cancer, time interval between cancer diagnosis and PE occurrence, the type of therapy received and the presence of metastases, clinical signs and symptoms, predisposing factors for PE development, laboratory data, radiological findings, electrocardiography findings, and the type of therapy received for PE and outcomes in a follow-up period of 6 months. In total, 60 cancer patients were enrolled. The majority of the cancer patients were males. The most common type of cancer observed was lung cancer. The majority of cases of PE occurred within the first year from the time of cancer diagnosis, while the majority of patients had already developed metastases. In addition, the majority of cancer patients had received chemotherapy over the past month, while they were not receiving anticoagulants and had central obstruction. A large proportion of patients had asymptomatic PE. The in-hospital mortality rate was 13.3% and no relapse or mortality were observed during the follow-up period. The present study demonstrates that elevated levels of lactic acid and an increased platelet count, as well as low serum levels of carcinoembryonic antigen, albumin and D-dimer, may be potential biomarkers for asymptomatic PE among cancer patients. 相似文献
999.
血小板对单核细胞促凝活性的影响 总被引:6,自引:1,他引:5
目的 研究血小板对单核细胞促凝活性的影响。方法 采用一期法血浆凝固时间测定单核细胞促凝活性;单抗中和法确定组织因子(TF)活性及P-选择素的作用。结果 ①内毒素激活的单核细胞促凝活性显著增高,TF单抗能明显阻断该效应;②胶原激活的血小板对单核细胞及内毒素激活的单核细胞的促凝活性均有明显的增强作用;③抗血小板P-选择素单抗能阻断活化的血小板对单核细胞促凝活性的增强效应。结论 ①单核细胞促凝活性是由于TF的表达;②血小板对单核细胞促凝活性的增强效应是通过P-选择素实现的。 相似文献
1000.
Jean-Louis Bayart Jonathan Degosserie Julien Favresse Constant Gillot Marie Didembourg Happy Phanio Djokoto Valrie Verbelen Gatien Roussel Cline Maschietto Franois Mullier Jean-Michel Dogn Jonathan Douxfils 《Viruses》2022,14(4)
Rapid antigen detection (RAD) tests are commonly used for the diagnosis of SARS-CoV-2 infections. However, with the continuous emergence of new variants of concern (VOC), presenting various mutations potentially affecting the nucleocapsid protein, the analytical performances of these assays should be frequently reevaluated. One hundred and twenty samples were selected and tested with both RT-qPCR and six commercial RAD tests that are commonly sold in Belgian pharmacies. Of these, direct whole-genome sequencing identified the strains present in 116 samples, of which 70 were Delta and 46 were Omicron (BA.1 and BA.1.1 sub-lineages, respectively). The sensitivity across a wide range of Ct values (13.5 to 35.7; median = 21.3) ranged from 70.0% to 92.9% for Delta strains and from 69.6% to 78.3% for Omicron strains. When taking swabs with a low viral load (Ct > 25, corresponding to <4.9 log10 copies/mL), only the Roche RAD test showed acceptable performances for the Delta strains (80.0%), while poor performances were observed for the other RAD tests (20.0% to 40.0%). All the tested devices had poor performances for the Omicron samples with a low viral load (0.0% to 23.1%). The poor performances observed with low viral loads, particularly for the Omicron strain, is an important limitation of RAD tests, which is not sufficiently highlighted in the instructions for use of these devices. 相似文献