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991.
Karim Ravilevich Muratov Timur Rizovich Ablyaz Evgeny Anatolevich Gashev Irina Georgievna Goryacheva 《Materials》2022,15(9)
The regularities of the formation of the resulting raster tool trajectories based on Lissajous figures for the lapping process of planes are established. This makes it possible to maximize the cutting ability of the tool, which contributes to its more uniform wear and increased productivity and processing quality. Optimal parameters of productivity and roughness of the treated surface during lapping of zirconium ceramics are achieved through the use of ASM paste 28/20 µm. Based on Preston’s hypothesis, an exponential dependence of the change in the contact area during the lapping of planes of different initial shape of the macrorelief is obtained. The obtained theoretical and practical results of the study of the process of flat lapping with constant and variable clamping force of the treated surface to the surface of the tool. The influence of the force factor on the formation of the surface in the process of abrasive lapping has been established. Studies have been carried out and the main technological recommendations of precision surface treatment of workpieces based on hard, brittle ceramic material and bronze samples on equipment with a raster trajectory of the tool movement are presented. The optimal pressure value when processing ceramics should be considered 203–270 kPa (2.1–2.8 kg/cm2). 相似文献
992.
目的 探讨控制营养状态(CONUT)评分对人表皮生长因子受体2(HER2)阳性早期乳腺癌患者复发转移中的预测价值。方法 将2012年1月至2020年10月于新疆医科大学附属肿瘤医院行手术切除并接受曲妥珠单抗治疗的154例HER2阳性早期乳腺癌患者为研究对象进行回顾性分析。基于患者术前血清白蛋白、总胆固醇水平及外周血淋巴细胞计数,计算CONUT评分。通过受试者操作特征曲线(ROC曲线)对CONUT评分截止点进行分类:高CONUT与低CONUT组。组间基线特征分布的比较采用卡方χ2检验或Fisher确切概率法。绘制Kaplan-Meier曲线,并通过单因素和多因素Cox回归分析确定CONUT评分与乳腺癌患者复发转移的关系。结果 ROC曲线表明CONUT评分预测乳腺癌患者术后复发转移的最佳截止点为2.5,曲线下面积(AUC)为0.689 (95%CI=0.577~0.801)。基于此截止点,将所有患者分为高CONUT组(≥3分)与低CONUT组(<3分)。Kaplan-Meier曲线展示两组患者的5年无复发生存(RFS)率分别为69.7%和86.9%,差异具有统计学意义(χ2=8.00... 相似文献
993.
Zoia R. Korobova Elena V. Zueva Natalia A. Arsentieva Oleg K. Batsunov Natalia E. Liubimova Irina V. Khamitova Raisa N. Kuznetsova Artem A. Rubinstein Tikhon V. Savin Oksana V. Stanevich Alexandr N. Kulikov Dmitry E. Pevtsov Areg A. Totolian 《Viruses》2022,14(5)
IgG is the most prominent marker of post-COVID-19 immunity. Not only does this subtype mark the late stages of infection, but it also stays in the body for a timespan of at least 6 months. However, different IgG subclasses have different properties, and their roles in specific anti-COVID-19 responses have yet to be determined. We assessed the concentrations of IgG1, IgG2, IgG3, and IgG4 against different SARS-CoV-2 antigens (N protein, S protein RBD) using a specifically designed method and samples from 348 COVID-19 patients. We noted a statistically significant association between severity of COVID-19 infection and IgG concentrations (both total and subclasses). When assessing anti-N protein and anti-RBD IgG subclasses, we noted the importance of IgG3 as a subclass. Since it is often associated with early antiviral response, we presumed that the IgG3 subclass is the first high-affinity IgG antibody to be produced during COVID-19 infection. 相似文献
994.
Irina Stoian Bogdan Manolescu Valeriu Atanasiu Olivera Lupescu 《Central European Journal of Medicine》2007,2(4):361-378
Erythropoietin (EPO) is one of the main cytokines involved in the regulation of erythropoiesis. The main site of EPO production
are the kidneys. An altered EPO production leads to pathological conditions such as anemia and polycythaemia. Due to the progressive
loss of renal peritubular cells, patients with chronic kidney disease (CKD) have low EPO plasma levels. This decreases erythron
stimulation with the direct consequence of developing anemia. Before the introduction in the clinical practice of rHuEpo,
in the late 1980s, the only solution for treating this type of anemia were blood transfusions and anabolic steroids. Even
rHuEpo has proven to be safe and effective for treatment of anemias, there are some concerns about its cost, the need for
frequent parenteral administration, and development of anti-EPO antibodies. These inconveniences prompted the search for novel
erythropoiesis stimulating agents. Different strategies lead to isolation or chemical synthesis of such agents as darbepoetin
alfa and EPO mimetics. In this review, we present some general aspects of EPO biology, with emphasis on chronic renal failure,
and expose some of the alternatives to EPO used for anemia correction. 相似文献
995.
Marian Novac Adina Magdalena Musuc Emma Adriana Ozon Iulian Sarbu Mirela Adriana Mitu Adriana Rusu Simona Petrescu Irina Atkinson Daniela Gheorghe Dumitru Lupuliasa 《Materials》2022,15(15)
The development of new orally dispersible tablets containing amlodipine (AML) inclusion complexes in hydroxypropyl-β-cyclodextrin (HP-β-CD) and in methyl-β-cyclodextrin (Me-β-CD) was studied. The methods of obtaining amlodipine and the physical and chemical properties of the inclusion complexes using the two cyclodextrins was investigated separately. Solid inclusion complexes were obtained by three methods: kneading, coprecipitation, and lyophilization, at a molar ratio of 1:1. For comparison, a physical mixture in the same molar ratio was prepared. The aim of the complexation process was to improve the drug solubility. As the lyophilization method leads to a complete inclusion of the drug in the guest molecule cavity, for both used cyclodextrins, these types of compounds were selected as active ingredients for the design of orally dispersible tablets. Subsequently, the formulation of the orodispersible tablets containing AML-HP-β-CD and AML-Me-β-CD inclusion complexes and quality parameters of the final formulation were evaluated. The results prove that F1 and F4 formulations, based on silicified microcrystalline cellulose, which contains insignificant proportions of very small or very large particles, had the lowest moisture degree (3.52% for F1 and 4.03% for F4). All of these demonstrate their porous structure, which led to good flowability and compressibility performances. F1 and F4 formulations were found to be better to manufacture orally dispersible tablets. 相似文献
996.
Camelia Ungureanu Gratiela Teodora Tihan Roxana Gabriela Zgrian Irina Fierascu Anda Maria Baroi Silviu Rileanu Radu Claudiu Fierscu 《Materials》2022,15(15)
Nowadays, special importance is given to quality control and food safety. Food quality currently creates significant problems for the industry and implicitly for consumers and society. The effects materialize in economic losses, alterations of the quality and organoleptic properties of the commercial products, and, last but not least, they constitute risk factors for the consumer’s health. In this context, the development of analytical systems for the rapid determination of the sanitary quality of food products by detecting possible pathogenic microorganisms (such as Escherichia coli or Salmonella due to the important digestive disorders that they can cause in many consumers) is of major importance. Using efficient and environmentally friendly detection systems for identification of various pathogens that modify food matrices and turn them into food waste faster will also improve agri-food quality throughout the food chain. This paper reviews the use of metal nanoparticles used to obtain bio nanosensors for the purpose mentioned above. Metallic nanoparticles (Au, Ag, etc.) and their oxides can be synthesized by several methods, such as chemical, physical, physico-chemical, and biological, each bringing advantages and disadvantages in their use for developing nanosensors. In the “green chemistry” approach, a particular importance is given to the metal nanoparticles obtained by phytosynthesis. This method can lead to the development of good quality nanoparticles, at the same time being able to use secondary metabolites from vegetal wastes, as such providing a circular economy character. Considering these aspects, the use of phytosynthesized nanoparticles in other biosensing applications is also presented as a glimpse of their potential, which should be further explored. 相似文献
997.
Alexandra Mataleru Alexandra Sabina Cojocariu Andra Oancea Maria-Magdalena Leon-Constantin Mihai Roca Ioana Mdlina Zota Irina Mihaela Abdulan Cristina Rusu Laura Mihaela Trandafir Alexandru Dan Costache Elena Cojocaru Iulia Cristina Roca Florin Mitu 《Nutrients》2022,14(15)
(1) Background: Familial hypercholesterolemia (FH) is a genetic autosomal dominant disorder characterized by elevated levels of low-density lipoprotein cholesterol (LDL) that develops deposits of lipids in the arterial wall. Since it is underdiagnosed and undertreated, the disease has a high risk of premature cardiovascular disease and death. Patients are not always aware of the changes they should make in their diet. Thus, our study aimed to evaluate through a food frequency questionnaire their eating habits. (2) Methods: We included 70 patients with FH and 20 subjects in a control group that were evaluated through a physical examination and blood tests. They also completed a food frequency questionnaire. (3) Results: Throughout our study, we observed several aspects: regardless of age, patients with FH had higher carbohydrate intakes compared to the control group; from the same group, a positive correlation was observed between salami intake and the levels of glucose and glycated hemoglobin. Moreover, the sour cream preference was associated with higher liver function tests. In the control group, we observed a higher intake of pasta and fast food and fewer fruit portions. (4) Conclusions: As far as we know, this is the first study from Romania that evaluated the eating habits of patients diagnosed with FH. Our study reveals that, although patients with FH avoid junk food, they still have a high intake of carbohydrates when compared to the control group. Further research is needed in order to get a comprehensive nutritional evaluation of these patients. 相似文献
998.
Alexis Sentís Irina Kislaya Nathalie Nicolay Hinta Meijerink Jostein Starrfelt Ivn Martínez-Baz Jesús Castilla Katrine Finderup Nielsen Christian Holm Hansen Hanne-Dorthe Emborg Anthony Nardone Tarik Derrough Marta Valenciano Baltazar Nunes Susana Monge the VEBIS-Lot working group VEBIS-Lot working group Ausenda Machado Carlos Dias Itziar Casado Cristina Burgui Amparo Larrauri Clara Mazagatos 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(30)
By employing a common protocol and data from electronic health registries in Denmark, Navarre (Spain), Norway and Portugal, we estimated vaccine effectiveness (VE) against hospitalisation due to COVID-19 in individuals aged ≥ 65 years old, without previous documented infection, between October 2021 and March 2022. VE was higher in 65–79-year-olds compared with ≥ 80-year-olds and in those who received a booster compared with those who were primary vaccinated. VE remained high (ca 80%) between ≥ 12 and < 24 weeks after the first booster administration, and after Omicron became dominant. 相似文献
999.
Vladimir I. Rozhdestvenskiy Vlada V. Titova Irina A. Gorkovaya Dmitry O. Ivanov Yuri S. Aleksandrovich 《Clinical Medicine & Research》2022,20(1):23
Objective: To study burnout of Russian physicians in the conditions of COVID-19 pandemic and how their work with coronavirus-infected patients influenced it. According to a three-factor model of burnout developed by Maslach and Jackson, this syndrome includes emotional exhaustion, depersonalization, and reduction of personal accomplishment. Design: A cross-sectional survey study. Setting: Large medical practice. Participants: Physicians of different specialties. Methods: Data collection was conducted from June 23 to July 12, 2020. We developed a Google form including a questionnaire and psychological inventories and placed it in a medical portal. Maslach Burnout Inventory — Human Services Survey for Medical Personnel was used to study burnout; the Hospital Anxiety and Depression Scale was used to determine anxiety and depression. Results: Of all the physicians who took part in the study (N = 599), 31.2 % worked with coronavirus-infected patients. Of the medical personnel who treated COVID-19 patients, 63.6% noted increased workload during the pandemic. Compared to other physicians, they more often had a high degree of emotional exhaustion (43.3 % vs 33.0 %, φ* = 2.404, P ≤ 0.01) and depersonalization (41.7 % vs 34, 0%, φ* = 1.803, P ≤ 0.05). An overwhelming majority of physicians, without any dependence on work with infected patients, had an absence of anxiety and depression. The identified interrelations between the symptoms of burnout, anxiety, depression; age and career stage in medical personnel were identical, except for weak correlations between age and emotional exhaustion (rs = -0.097, P ≤ 0.05), as well as career stage and personal accomplishment (rs = 0.102, P ≤ 0.05) in those physicians who worked with COVID-19 patients. The structure of burnout was identical in all physicians and did not depend on interaction with the infected patients. Conclusion: Public health authorities should reduce the workload on physicians involved in treating infected patients against the backdrop of the pandemic. Psychotherapeutic measures focused on preventing burnout should reduce its number among physicians interacting with patients infected with the coronavirus. 相似文献
1000.
Neta S Zuckerman Itay Bar-Or Danit Sofer Efrat Bucris Hagar Morad Lester M Shulman Nofar Levi Leah Weiss Irina Aguvaev Zvi Cohen Klil Kestin Rinat Vasserman Michal Elul Ilana S Fratty Miranda Geva Marina Wax Oran Erster Ruth Yishai Lior Hecht-Sagie Sharon Alroy-Preis Ella Mendelson Merav Weil 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(37)
We report an emergence and increase in poliovirus type 2 detection via routine wastewater surveillance in three non-overlapping regions in the Jerusalem region, Israel, between April and July 2022. Sequencing showed genetic linkage among isolates and accumulation of mutations over time, with two isolates defined as vaccine-derived polioviruses (VDPV). This demonstrates the emergence and potential circulation of type 2 VDPV in a high-income country with high vaccine coverage and underscores the importance of routine wastewater surveillance during the polio eradication. 相似文献