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991.
992.
目的构建抑制人聚ADP核糖聚合酶1(hPARP1)活性的短发夹RNA(shorthairpinRNA,shRNA)表达载体。方法化学合成2对编码短发夹RNA序列的、靶向hPARP1基因的寡核苷酸,各69对碱基,退火,然后利用BamHⅡ及EcoRⅠ与pSIRENRetroQ载体连接。用EcoRⅠ及BglⅡ切取其中U6启动子及下游的shRNA部分,与pEGFPC1载体重组构建pEGFPC1shRNA载体。结果重组构建的pEGFPC1P1、pEGFPC1P2、pEGFPC1N载体经双酶切电泳分析及插入基因片段序列分析,结果表明330个碱基成功插入到预计位点。结论载体的成功构建,为进一步研究聚ADP核糖聚合酶在DNA修复过程中的功能打下基础。 相似文献
993.
994.
为观察全营养素混合液(TNA)对早产儿血清渗透压的影响,按6ml·kg-1·h-1的速度给早产儿静脉输入TNA,测定输注前及输注过程中的血钠、血糖、BUN和血清渗透压,并计算渗透压间隙(OG)。结果显示输注前及输注过程中血清渗透压、OG及血糖无显著性差异,提示TNA液在一定速度内输注对早产儿血清渗透压及血糖无明显影响。 相似文献
995.
为评价反映儿童锌缺乏的敏感指标.方法 我们对300名3~6岁儿童进行膳食调查与体格检查,同时测定了锌缺乏组和对照组儿童的尿锌与尿肌酐比值,血清ALP活性,血清胆固醇水平及锌缺乏儿童补锌治疗前后上述指标的变化.结果 锌缺乏组与对照组尿锌与尿肌酐比值,血清ALP活性有显著性差异.锌缺乏组儿童血浆锌,尿锌与尿肌酐比值,血清ALP活性,血清胆固醇水平在补锌治疗前后有显著性差异.结论 血浆锌和血清ALP同时降低可以预示儿童体内锌缺乏,需要补锌治疗;尿锌与尿肌酐比值能较敏感地反映儿童的锌营养状况;胆固醇与锌营养之间的关系值得进一步研究. 相似文献
996.
Yang Dai Jingcao Huang Pu Kuang Yiguo Hu Qiang Zeng Wanhua Zhang He Li Fangfang Wang Tingting Guo Dan Zhang Dongni Yi Yuhuan Zheng Ting Liu 《American journal of cancer research》2022,12(6):2817
Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) is a high-risk disease subtype with a dismal prognosis. Inhibiting BCR-ABL kinase alone is insufficient to eradicate Ph+ALL clones, and alternative BCR-ABL-dependent and -independent pathways need to be targeted as an effective strategy. Our study revealed that the combination of dasatinib and interferon-α showed synergistic activity against Ph+ALL, inducing mitochondrial dysfunction and causing necrosis-like cell lysis. Mechanistic studies showed that the induced cell death was caspase-3-independent. Canonical necroptosis signals, such as RIP1 and MLKL, were not activated; instead, the pyroptosis executor Gasdermin D was upregulated expression and activated. The expression levels of extracellular ATP and IL-1β were also upregulated, both of which are markers of pyroptotic cell death. In a murine Ph+ALL model, the dual drug treatment prolonged the survival of tumor-bearing mice. More importantly, we incorporated the dual drugs to maintenance therapy in 39 patients who were unfit for allogeneic stem cell transplantation (allo-HSCT). The median follow-up was 28.5 months, the 4-year disease-free survival and overall survival rates were 52.2% and 65.2%, respectively. Our data suggest that the combination of dasatinib and interferon-α has potential synergistic activity against Ph+ALL and shows promise as a maintenance therapy for Ph+ALL patients who are unfit for allo-HSCT. 相似文献
997.
Shujiao He Minjie Zhang Jieying Li Weiqiang Zhao Li Yu Ying Han Yanbin Pang 《The Journal of international medical research》2022,50(5)
A Y842D mutation within the activation loop of fms-like tyrosine kinase 3 (FLT3) has been shown to confer strong resistance to sorafenib in vitro. Whether this type of mutation exerts clinically significant effects in patients with acute myeloid leukaemia (AML) remains unclear. Here, a novel Y842D activating mutation within the kinase domain of FLT3, in a pregnant patient with de novo hyperleucocyte acute myeloid leukaemia, is described. Following induction failure with standard dose idarubicin and cytarabine (IA), the patient received re-induction combined with midostaurin, a promising agent targeting mutant-FLT3, and IA regimen. Fortunately, morphological remission was achieved. During the period of midostaurin treatment, the patient exhibited a symptom that was characteristic of differentiation syndrome, which disappeared following treatment with methylprednisolone. The present case revealed that Y842D, an uncommon activating mutation in the activation loop of FLT3, may be a midostaurin-sensitive mutation type in patients with acute myeloid leukaemia. 相似文献
998.
Junlong Zhang Hongle He Chengqiang Mo Zhenhua Chen Shuangjian Jiang 《The Journal of international medical research》2022,50(6)
Vascular air embolism (VAE) is a rare complication of percutaneous nephrolithotomy. Paradoxical air embolization resulting from VAE may be more likely to occur in patients with an atrial-septal defect, such as patent foramen ovale. Here, the case of a female patient with VAE that occurred during percutaneous nephrolithotomy is presented. Although the patient was diagnosed with patent foramen ovale, she recovered well without any severe paradoxical air embolization symptoms. To our knowledge, this is the first report of VAE with paradoxical air embolization that occurred in a patient with patent foramen ovale during percutaneous nephrolithotomy that was conducted without pneumopyelography. 相似文献
999.
Ke Li Shuping Sun Zhanyou Xue Sufen Chen Chunyang Ju Dongmei Hu Xiaoyu Gao Yanhong Wang Dan Wang Jianjun Chen Li Li Jing Liu Mingjie Zhang Zhihua Jia Xun Han Huanxian Liu Mianwang He Wei Zhao Zihua Gong Shuhua Zhang Xiaoxue Lin Yingyuan Liu Shengshu Wang Shengyuan Yu Zhao Dong 《The journal of headache and pain》2022,23(1)
BackgroundThere have been a few studies regarding the pre-attack symptoms (PAS) and pre-episode symptoms (PES) of cluster headache (CH), but none have been conducted in the Chinese population. The purpose of this study was to identify the prevalence and features of PAS and PES in Chinese patients, as well as to investigate their relationships with pertinent factors.MethodsThe study included patients who visited a tertiary headache center and nine other headache clinics between January 2019 and September 2021. A questionnaire was used to collect general data and information about PAS and PES.ResultsAmong the 327 patients who met the CH criteria (International Classification of Headache Disorders, 3rd edition), 269 (82.3%) patients experienced at least one PAS. The most common PAS were head and facial discomfort (74.4%). Multivariable logistic regression analysis depicted that the number of triggers (OR = 1.798, p = 0.001), and smoking history (OR = 2.067, p = 0.026) were correlated with increased odds of PAS. In total, 68 (20.8%) patients had PES. The most common symptoms were head and facial discomfort (23, 33.8%). Multivariable logistic regression analysis showed that the number of triggers were associated with increased odds of PES (OR = 1.372, p = 0.005).ConclusionsPAS are quite common in CH patients, demonstrating that CH attacks are not comprised of a pain phase alone; investigations of PAS and PES could help researchers better understand the pathophysiology of CH. 相似文献
1000.
Emilia A. Korhonen Aino Murtomki Sawan Kumar Jha Andrey Anisimov Anne Pink Yan Zhang Simon Stritt Inam Liaqat Lukas Stanczuk Laura Alderfer Zhiliang Sun Emmi Kapiainen Abhishek Singh Ibrahim Sultan Anni Lantta Veli-Matti Leppnen Lauri Eklund Yulong He Hellmut G. Augustin Kari Vaahtomeri Pipsa Saharinen Taija Mkinen Kari Alitalo 《The Journal of clinical investigation》2022,132(15)
Vascular endothelial growth factor C (VEGF-C) induces lymphangiogenesis via VEGF receptor 3 (VEGFR3), which is encoded by the most frequently mutated gene in human primary lymphedema. Angiopoietins (Angs) and their Tie receptors regulate lymphatic vessel development, and mutations of the ANGPT2 gene were recently found in human primary lymphedema. However, the mechanistic basis of Ang2 activity in lymphangiogenesis is not fully understood. Here, we used gene deletion, blocking Abs, transgene induction, and gene transfer to study how Ang2, its Tie2 receptor, and Tie1 regulate lymphatic vessels. We discovered that VEGF-C–induced Ang2 secretion from lymphatic endothelial cells (LECs) was involved in full Akt activation downstream of phosphoinositide 3 kinase (PI3K). Neonatal deletion of genes encoding the Tie receptors or Ang2 in LECs, or administration of an Ang2-blocking Ab decreased VEGFR3 presentation on LECs and inhibited lymphangiogenesis. A similar effect was observed in LECs upon deletion of the PI3K catalytic p110α subunit or with small-molecule inhibition of a constitutively active PI3K located downstream of Ang2. Deletion of Tie receptors or blockade of Ang2 decreased VEGF-C–induced lymphangiogenesis also in adult mice. Our results reveal an important crosstalk between the VEGF-C and Ang signaling pathways and suggest new avenues for therapeutic manipulation of lymphangiogenesis by targeting Ang2/Tie/PI3K signaling. 相似文献