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71.
Tau proteins are encoded by a single gene which is regulated by a unique promoter. The proximal 196 base pairs of the tau 5′ flanking region confers tau protein with neuronal specific expression and nerve growth factor inducibility. We tested tau promoter activity in neuronally differentiated embryonal carcinoma cells, the P19 mouse blastoderm cell line. In these experiments, we examined the temporal expression pattern of the tau promoter and compared it to other viral and cellular promoters. Tau promoter activity increases significantly with differentiation, specifically during neurite initiation. In addition, tau promoter activity in neuronally differentiated P19 cells was significantly greater than all five of the other neuronal or non neuronal promoters tested. All other promoters displayed low levels of promoter activity throughout retinoic acid induced neuronal differentiation of P19 cells. Taken together, our results suggest that the tau promoter is a good choice for ectopic expression of exogenous genes in P19 cells, which serves as a differentiating neuronal model system. 相似文献
72.
目的探讨系统性红斑狼疮患者外周血中B淋巴细胞及其活化状况与疾病活动性的关系。方法应用流式细胞术检测活动期与稳定期系统性红斑狼疮患者外周血中CD19+、CD23+/CD19+及HLA-DR+/CD19+细胞的表达情况;同时应用免疫学方法检测血清中ds-DNA与ANA水平。结果活动期患者CD19+、CD23+/CD19+及HLA-DR+/CD19+细胞表达率均高于稳定期患者及正常对照组,差异均有显著性意义;稳定期患者CD23+/CD19+表达很低,而HLA-DR+/CD19+双阳性细胞表达率高于正常对照组,但差异无显著性意义;且CD23+/CD19+双阳性细胞表达率与病情积分、ds-DNA及ANA均成正相关(P<0.01),而HLA-DR+/CD19+双阳性细胞与三者无相关关系(P>0.05)。结论活动期与稳定期患者均存在B淋巴细胞的克隆性增生与异常活化,B细胞的异常活化是病情活动的直接原因,晚期B细胞的异常活化是系统性红斑狼疮患者难彻底治愈与病情反复的原因之一。 相似文献
73.
目的探讨髋臼骨折手术并发症发生原因及防治措施。方法我院对手术治疗的45例髋臼骨折中发生并发症的20例进行分析。结果本组总的并发症发生率为44.4%。其中肺栓塞1例,下肢深静脉血栓行成2例,医源性坐骨神经损伤1例,创伤性关节炎12例,异位骨化7例,股骨头缺血坏死5例。结论选择合适的手术入路,尽早手术,提高手术技巧和复位质量,术后正确有效的干预措施、合理的早期功能锻炼是防治髋臼骨折手术并发症的关键。 相似文献
74.
M Al-Ramahi M Bata I Sumreen M Amr 《International journal of gynaecology and obstetrics》2006,94(1):33-36
OBJECTIVE: To evaluate whether saline wound irrigation decreases the incidence of wound infection following abdominal gynecologic surgery. METHOD: In this prospective randomized study, 104 patients underwent wound irrigation before wound closure following abdominal gynecologic surgery and 102 patients did not. RESULTS: There were no significant differences between the 2 groups in patient characteristics or in factors influencing the incidence of wound infection after abdominal gynecologic surgery. The incidence of wound infection was 10.6% among women who underwent wound irrigation and 9.8% among those who did not, and the difference was not statistically significant. CONCLUSION: Saline wound irrigation before abdominal wall closure is not helpful in decreasing the incidence of wound infection after abdominal gynecologic surgery. 相似文献
75.
目的:考察中国健康人群和甲亢患者细胞色素氧化酶CYP2C19遗传多态性的相关性.方法:应用限制性片段长度多态性分析法(PCR-RFLP)对66例甲亢患者和74例健康志愿者进行了基因多态性分析.结果:甲亢患者和健康志愿者中基因型为野生型纯合子wt/wt的分别为34.85%(23/66)和41.89(31/74);基因型为杂合子wt/m1和wt/m2的分别为50.0%(33/66)和45.94%(34/74);基因型为突变型纯合子ml/ml和ml/m2的为15.15%(10/66)和12.16%(9/74).在本实验中未发现m2/m2基因型.甲亢患者和健康志愿受试者的wt/wt和ml/m1的频率没有显著差别.结论:中国甲亢患者和健康人群细胞色素氧化酶CYP2C19遗传多态性在统计学上没有差别. 相似文献
76.
Anood Alassaf Khaled Ellithy Tejas Mehta Walid Aljbawi Hossamaldein Ali Ashraf Soliman Mohammed Al Amri Abdulqadir J. Nashwan 《Clinical Case Reports》2022,10(8)
Our patient is a 3‐week‐old female neonate, presented with complaints of low‐grade fever and a congested nose for one day. Eventually, she developed progressive desaturation, hypotension, and poor perfusion due to severe pulmonary hemorrhage. Then, she developed cardiac arrest and was declared dead. 相似文献
77.
Gro Tunheim Gunnar
yvind Isaksson R Adity Chopra Audun Aase AnneMarte Bakken Kran John Torgils Vaage Fridtjof LundJohansen Olav Hungnes 《Influenza and other respiratory viruses》2022,16(6):1004
BackgroundOne year into the COVID‐19 pandemic, the cumulative number of confirmed COVID‐19 cases in Norway was still low. In January 2021, when the Norwegian COVID‐19 vaccination campaign started, the national seroprevalence estimate of SARS‐CoV‐2 antibodies was 3.2%. We have conducted a nationwide cross‐sectional study in August 2021 to investigate the overall prevalence of SARS‐CoV‐2 antibodies in Norway after 8 months of COVID‐19 mass vaccination and a third wave of SARS‐CoV‐2 infection.MethodsResidual sera were collected from laboratories across Norway in August 2021. In IgG antibodies against the spike protein, the spike receptor binding domain (RBD) and the nucleocapsid protein of SARS‐CoV‐2 were measured by a bead‐based flow cytometric assay.ResultsIn total, 1926 residual sera were collected from individuals aged 0–98 years; 55.1% were from women. The overall national estimated seroprevalence from vaccination and/or infection was 62.6% (credible interval [CrI] 60.1%–65.2%) based on having antibodies against both spike and RBD. Estimated seroprevalence increased with age. Among all samples, 11.7% had antibodies against nucleocapsid. For unvaccinated children <12 years, the seroprevalence estimate due to SARS‐CoV‐2 infection was 12.5% (95% CrI 9.3%–16.1%). Of seropositive samples from the unvaccinated children, 31.9% lacked anti‐nucleocapsid antibodies.ConclusionsThe high overall SARS‐CoV‐2 seroprevalence estimates are in line with Norwegian registry data. Vaccination, not infection, contributed the most to the high seroprevalence in August 2021. Lack of antibodies against nucleocapsid should not automatically be interpreted as absence of previous infection as this could lead to underestimation of COVID‐19 cases in seroprevalence studies. 相似文献
78.
Patients with chronic diseases are severely affected by acute coronavirus syndrome. In this regard, patients with beta thalassemia intermedia and diabetes mellitus (DM) are also at high risk for coronavirus‐induced respiratory failure. The present study aimed to report a case with COVID‐19 with a history of chronic diseases, beta thalassemia intermedia, and DM. A 25‐year‐old man visited with complaints of severe shortness of breath, fever, cough without sputum, and tachypnea and admitted to the Intensive Care Unit. The patient had a history of DM, beta thalassemia intermedia, and pervious history of the splenectomy. In peripheral complete blood count (CBC diff), the number of white blood cell count was 41,100 of which 38.6% were lymphocytes. We measured the normal platelet count, hemoglobin level (9.4), and red blood cell count (3.56). ESR was 97, CRP = pos+++ and PCR was positive. The high‐resolution lung CT indicated ground glass opacities in peripheral areas. The patient underwent 13 days of oxygen therapy with reservoir bag‐mask, non‐invasive ventilation, nasal oxygen, and pharmacological treatment with IFN‐β1a and meropenem, and finally discharged with an improvement of the clinical condition. Timely initiation of treatment is very important and significant for patients with beta thalassemia intermedia with COVID‐19, especially despite the underlying disease of DM. According to the present report, the use of IFN‐β1a was effective as a treatment option for COVID‐19. 相似文献
79.
《Influenza and other respiratory viruses》2022,16(6):975
BackgroundWe estimated SARS‐CoV‐2 Delta‐ and Omicron‐specific effectiveness of two and three mRNA COVID‐19 vaccine doses in adults against symptomatic illness in US outpatient settings.MethodsBetween October 1, 2021, and February 12, 2022, research staff consented and enrolled eligible participants who had fever, cough, or loss of taste or smell and sought outpatient medical care or clinical SARS‐CoV‐2 testing within 10 days of illness onset. Using the test‐negative design, we compared the odds of receiving two or three mRNA COVID‐19 vaccine doses among SARS‐CoV‐2 cases versus controls using logistic regression. Regression models were adjusted for study site, age, onset week, and prior SARS‐CoV‐2 infection. Vaccine effectiveness (VE) was calculated as (1 − adjusted odds ratio) × 100%.ResultsAmong 3847 participants included for analysis, 574 (32%) of 1775 tested positive for SARS‐CoV‐2 during the Delta predominant period and 1006 (56%) of 1794 participants tested positive during the Omicron predominant period. When Delta predominated, VE against symptomatic illness in outpatient settings was 63% (95% CI: 51% to 72%) among mRNA two‐dose recipients and 96% (95% CI: 93% to 98%) for three‐dose recipients. When Omicron predominated, VE was 21% (95% CI: −6% to 41%) among two‐dose recipients and 62% (95% CI: 48% to 72%) among three‐dose recipients.ConclusionsIn this adult population, three mRNA COVID‐19 vaccine doses provided substantial protection against symptomatic illness in outpatient settings when the Omicron variant became the predominant cause of COVID‐19 in the United States. These findings support the recommendation for a third mRNA COVID‐19 vaccine dose. 相似文献
80.
Yao Lin Yiming Shao Yuchun Liu Ruoxuan Yang Shuanglin Liao Shuai Yang Mingwei Xu Junbing He 《Renal failure》2022,44(1):1263
BackgroundNafamostat mesilate (NM), a broad-spectrum and potent serine protease inhibitor, can be used as an anticoagulant during extracorporeal circulation, as well as a promising drug effective against coronavirus disease 2019 (COVID-19). We conducted a systematic meta-analysis to evaluate the safety and efficacy of NM administration in critically ill patients who underwent blood purification therapy (BPT).MethodsThe Cochrane Library, Web of Science and PubMed were comprehensively searched from inception to August 20, 2021, for potential studies.ResultsFour randomized controlled trials (RCTs) and seven observational studies with 2723 patients met the inclusion criteria. The meta-analysis demonstrated that conventional therapy (CT) significantly increased hospital mortality compared with NM administration (RR = 1.25, p = 0.0007). In subgroup analyses, the in-hospital mortality of the NM group was significantly lower than that of the anticoagulant-free (NA) group (RR = 1.31, p = 0.002). The CT interventions markedly elevated the risk ratio of bleeding complications by 45% (RR = 1.45, p = 0.010) compared with NM interventions. In another subgroup analysis, NM used exhibited a significantly lower risk of bleeding complications than those of the low-molecular-weight heparin (LMWH) used (RR = 4.58, p = 0.020). The filter lifespan was decreased significantly (MD = −10.59, p < 0.0001) in the NA groups compared with the NM groups. Due to the poor quality of the included RCTs, these results should be interpreted with caution.ConclusionGiven the better survival outcomes, lower risk of bleeding, NM anticoagulation seems to be a safe and efficient approach for BPT patients and could yield a favorable filter lifespan. More multi-center RCTs with large samples are required for further validation of this study. 相似文献