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81.
目的:研究外源NO对刺五加种子解除休眠及萌发过程中内源激素及酶的变化规律,为打破刺五加种子休眠和人工栽培提供依据。方法:考察不同浓度(1,5,10,20 mmol·L~(-1))的外源NO供体硝普钠(SNP)处理刺五加种子,而后进行变温层积处理。采用高效液相色谱法检测出在不同层积时间(0,30,50,80,100,130 d)的内源激素赤霉素(GA3),脱落酸(ABA),吲哚乙酸(IAA),吲哚丁酸(IBA)及水杨酸(SA)含量变化。采用酶标仪全程监测体内酶[过氧化氢酶(CAT),超氧化物歧化酶(SOD),过氧化物酶(POD),丙二醛(MDA)]水平的变化。结果:在刺五加种子萌发过程中,GA3,IAA,IBA和SA的含量逐渐增大,脱落酸的含量逐渐减小。POD和MDA水平显著下降,CAT和SOD的酶活力显著上升。外源NO可以提高刺五加种子萌发率,缩短种子萌发时间,20 mmol·L~(-1)SNP促进种子萌发效果最为明显,10 mmol·L~(-1)SNP促进种子萌发效果最弱,呈"V"型变化。结论:SNP促进刺五加种子萌发可能通过提高种子萌发过程中的激素和酶的含量,以提高种子内源NO含量而实现。 相似文献
82.
目的 探讨乳腺癌新辅助化疗前后肿瘤组织病理信息的变化及对预后的影响。方法 对2014年1月—2016年5月就诊于辽宁省肿瘤医院乳腺外科并行规范乳腺癌新辅助化疗的177例患者回顾性分析,探讨乳腺癌新辅助化疗前后肿瘤组织病理信息的变化,并分析残余肿瘤组织病理信息对无病生存期(DFS)和总生存期(OS)的影响。结果 177例乳腺癌患者中位随访时间为37个月,37个月无病生存率和总生存率分别为84.0%和95.0%,4年无病生存率和总生存率分别为79.7%和81.1%。新辅助化疗后乳腺癌患者的DFS独立危险因素为原始T分期、原始N分期、存在脉管侵袭、新辅助化疗后Ki-67增加。OS的独立危险因素为原始T分期、原始N分期。而新辅助化疗前后ER状态的改变、PR状态的改变、HER-2状态的改变与患者预后无关(P>0.05)。结论 乳腺癌新辅助化疗前后分子生物学指标ER、PR、HER-2、Ki-67可以发生改变,但与乳腺癌患者预后无关。原始肿瘤T分期、原始肿瘤N分期、存在脉管侵袭和Ki-67增加是影响乳腺癌患者DFS的危险因素。原始肿瘤T分期、原始肿瘤N分期是影响乳腺癌患者OS的危险因素。 相似文献
83.
Tycel J. Phillips Jean-Marie Michot Vincent Ribrag 《Clinical Lymphoma, Myeloma & Leukemia》2021,21(1):8-20.e3
Although outcomes after first-line therapy for patients with indolent or aggressive non-Hodgkin lymphoma (NHL) are continually improving, relapse is still common. Current treatment options for patients with relapsed or refractory disease have limited efficacy, and various targeted therapies are under investigation to help improve outcomes in this patient population. The phosphatidylinositol 3-kinase (PI3K) pathway was identified as being involved in hematologic malignancies, leading to significant research for potential therapeutic agents. This has led to 3 PI3K inhibitors (idelalisib, copanlisib, and duvelisib) being approved for the treatment of patients with relapsed or refractory follicular lymphoma who have received at least 2 prior systemic therapies, with reported response rates of 40% to 59%. With potential class-specific and PI3K isoform–related toxicities that may limit clinical utility, the safety of the approved PI3K inhibitors has been carefully evaluated to weigh the risk/benefit ratio of therapy. Currently, there are no approved PI3K inhibitors for patients with aggressive NHL. A number of newer PI3K inhibitors are in clinical development for the treatment of relapsed or refractory NHL, aiming to improve treatment benefit for patients. We discuss a number of attributes that are important to increase the therapeutic potential of newer PI3K inhibitors. More promising results may come from combination trials with these newer PI3K inhibitors, developed to limit toxicities (including long-term adverse events), and other antitumor agents. 相似文献
84.
The interaction between tissues and biomaterials (BM) has the purpose of improving and replacing anatomical parts of the human body, avoiding the occurrence of adverse reactions in the host organism. Unfortunately, the early failure of implants cannot be currently avoided, since neither a good mixture of mechanical and chemical characteristics of materials nor their biocompatibility has been yet achieved. Bioactive glasses are recognized to be a fine class of bioactive substances for good repair and replacement. BM interact with living bones through the formation of a hydroxyapatite surface layer that is analogous to bones. Bioglasses’ composition noticeably affects their biological properties, as does the synthesis method, with the best one being the versatile sol-gel technique, which includes the change of scheme from a ‘sol’ fluid into a ‘gel’. This process is widely used to prepare many materials for biomedical implants (e.g., hip and knee prostheses, heart valves, and ceramic, glassy and hybrid materials to serve as carriers for drug release). Nanoparticles prepared by the sol-gel method are interesting systems for biomedical implementations, and particularly useful for cancer therapy. This review provides many examples concerning the synthesis and characterization of the above-mentioned materials either taken from literature and from recently prepared zirconia/polyethylene glycol (PEG) hybrids, and the corresponding results are extensively discussed. 相似文献
85.
Maamer Slimani Nicola Bragazzi Amri Hammami Hela Znazen Qian Yu Zhaowei Kong Liye Zou 《International Journal of Mental Health Promotion, The》2021,23(4):513-520
The present study aimed to determine the effect of wearing a face mask during aerobic dance exercise on cognitive function, more specifically on attention, as well as on perceived exertion and mood states. Thirteen healthy college students (9 males and 4 females: mean age = 17.5 years, height = 1.72 m, weight = 71.00 kg) volunteered to participate in this study. They were randomized to perform aerobic dance exercise while wearing a cloth face mask or no mask or a control condition (sitting on a comfortable chair and reading information about the health benefits of aerobic dance exercise) on three separate occasions (with at least one week of interval). Rate of perceived exertion (RPE), the Brunel Mood Scale (BRUMS) and d2 Attention assessment were assessed before and immediately after each condition. The results demonstrated higher concentration performance for the aerobic dance exercise without face mask than the control condition (p = 0.05). Post RPE and BRUMS fatigue subscale values were significantly higher in the aerobic dance exercise with face mask as compared to the aerobic dance exercise without face mask and control condition (all, p < 0.05). BRUMS vigor subscale value significantly differed across conditions (F = 113.84, p < 0.001, ES = 0.86) and was significantly higher in the aerobic dance exercise group without face mask as compared to the aerobic dance exercise with face mask and the control conditions (both, p < 0.001). This study suggests that face mask use during aerobic dance exercise with moderate intensity did not affect attention. Practitioners, students and athletes should avoid wearing face mask while practicing physical activity or aerobic dance exercise with moderate intensity to improve its acute effect on cognitive function. 相似文献
86.
Walid Kamal Abdelbasset Gopal Nambi Marwa M Eid Safaa M Elkholi 《World Journal of Psychiatry》2021,11(12):1267-1273
The corona virus disease 2019 (COVID-19) pandemic has resulted in most nations deciding upon self-isolation and social distancing policies for their citizens to control the pandemic and reduce hospital admission. This review aimed at evaluating the effect of physical activity on mental well-being during the COVID-19 pandemic. It was concluded that the COVID-19 pandemic may lead to augmented levels of angiotensin-converting enzyme (ACE)-2 that led to cardiovascular and neurological disorders associated with highly inflammatory effects of viral infection affecting the brain tissues leading to damage of the nervous system and resulting in cognition dysfunction, insulin sensitivity reduction, and behavioral impairments. Anxiety and depression may lead to negative effects on various quality of life domains, such as being physically inactive. Regular physical activities may reduce inflammatory responses, improve ACE-2 responses, and improve mental well-being during self-isolation and social distancing policies related to the COVID-19 pandemic. Further studies should be conducted to assess the different intensities of physical activities on cardiova scular function, and mental well-being during the COVID-19 pandemic. 相似文献
87.
Little is known on the association between movement behaviors including physical activity (PA), screen time (ST) and sleep (SLP) with depression in adolescents. This study aimed to explore the associations of PA, ST and SLP with depressive symptoms in adolescents. A total of 1,331 middle school students participated in this survey and provided valid data pertaining to the study variables. Self-reported questionnaires were used to collect information on participants’ sociodemographic parameters. The Health Behavior in School-aged Children Questionnaire was used to assess the PA (days for moderate to vigorous PA), ST (daily hours of ST) and SLP (daily hours of SLP). Study participants’ depressive symptoms were assessed using the Children’s Depression Inventory. Generalized linear models were used to estimate the associations of PA, ST and SLP with depressive symptoms. Of all the 1331 study participants, boys accounted for 51.31% and percentage of 7th, 8th and 9th graders were 52.44%, 23.22% and 24.34%, respectively. After controlling for sex, body mass index, grade, ethnicity, residence, siblings, perceived family affluence, father and mother educational level, only ST was positively associated with depressive symptoms (beta = 0.17, p = 0.005). This study suggests that excessive ST would be detrimental to depressive symptoms in adolescents. It may be effective to reduce ST for depression intervention or prevention. Future studies are encouraged to use an improved study design to confirm or negate this study’s research findings. 相似文献
88.
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90.
目的探讨生物型双极人工股骨头置换治疗老年股骨颈骨折的临床疗效。方法采用生物型双极人工股骨头置换治疗60例老年股骨颈骨折患者。末次随访采用Harris评分标准评价髋关节功能。结果患者均获得随访,时间6~12个月。手术时间38~62 min,术中出血量50~110 ml。手术切口均一期愈合。2例术后1周发生脑梗死,神经内科会诊治疗后症状好转,但肌力差,髋关节功能差。1例术后8个月因心脏病去世。未出现感染、假体松动、股骨头脱位等并发症。末次随访时根据Harris评分标准评价疗效:优46例,良9例,可2例,差2例。结论生物型双极人工股骨头置换治疗老年股骨颈骨折手术创伤小,术后下地活动早,并发症少,可有效提高患者生活质量。 相似文献