全文获取类型
收费全文 | 10110篇 |
免费 | 730篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 390篇 |
妇产科学 | 230篇 |
基础医学 | 1168篇 |
口腔科学 | 280篇 |
临床医学 | 849篇 |
内科学 | 2689篇 |
皮肤病学 | 185篇 |
神经病学 | 509篇 |
特种医学 | 240篇 |
外国民族医学 | 4篇 |
外科学 | 1391篇 |
综合类 | 285篇 |
一般理论 | 5篇 |
预防医学 | 717篇 |
眼科学 | 330篇 |
药学 | 755篇 |
中国医学 | 102篇 |
肿瘤学 | 655篇 |
出版年
2023年 | 130篇 |
2022年 | 301篇 |
2021年 | 500篇 |
2020年 | 253篇 |
2019年 | 321篇 |
2018年 | 363篇 |
2017年 | 267篇 |
2016年 | 309篇 |
2015年 | 331篇 |
2014年 | 440篇 |
2013年 | 499篇 |
2012年 | 762篇 |
2011年 | 805篇 |
2010年 | 409篇 |
2009年 | 353篇 |
2008年 | 545篇 |
2007年 | 481篇 |
2006年 | 461篇 |
2005年 | 433篇 |
2004年 | 396篇 |
2003年 | 339篇 |
2002年 | 325篇 |
2001年 | 127篇 |
2000年 | 153篇 |
1999年 | 143篇 |
1998年 | 76篇 |
1997年 | 63篇 |
1996年 | 53篇 |
1995年 | 44篇 |
1994年 | 40篇 |
1993年 | 33篇 |
1992年 | 113篇 |
1991年 | 62篇 |
1990年 | 85篇 |
1989年 | 80篇 |
1988年 | 92篇 |
1987年 | 78篇 |
1986年 | 67篇 |
1985年 | 68篇 |
1984年 | 44篇 |
1983年 | 35篇 |
1982年 | 31篇 |
1981年 | 31篇 |
1979年 | 54篇 |
1978年 | 22篇 |
1977年 | 23篇 |
1974年 | 21篇 |
1973年 | 21篇 |
1972年 | 21篇 |
1969年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
52.
Knock down of spinal NMDA receptors reduces NMDA and formalin evoked behaviors in rat 总被引:12,自引:0,他引:12
Chronic pain remains a major health problem afflicting an estimated 70% of patients with advanced cancer and inflammatory disorders, and up to 94% of patients with spinal cord injuries. Although progress has been made in the pharmacotherapy of chronic pain management, such as usage of adjuvant drugs and more effective methods of drug delivery, the mainstay of clinical pain management still depends on opiates. NMDA receptor activation, at the level of the spinal cord has been shown to play an important role in the facilitation of nociception (pain) in several animal models. Unfortunately, potent NMDA receptor antagonists, such as MK-801 and APV, have toxic properties and low safety margins that preclude their clinical use. We present evidence which indicates that the use of antisense oligonucleotides targeted to the NMDA-R1 receptor subunit (AS-NMDA-R1), but not sense, abolishes NMDA and formalin induced behaviors. Moreover, we demonstrate that spinal administration of AS-NMDA-R1 results in the abolition of staining for immunoreactive NMDA-R1 in the spinal cord. These data provide novel evidence supporting the feasibility of the use of gene therapy approaches in the management of neuropathic pain. 相似文献
53.
54.
55.
Hazreen Abdul Majid Ai Kah Ng Maznah Dahlui Shooka Mohammadi Mohd Nahar Azmi bin Mohamed Tin Tin Su Muhammad Yazid Jalaludin 《Nutrients》2022,14(13)
A healthy eating environment in the school setting is crucial to nurture the healthy eating pattern for youth. Thus, it helps to combat the obesity issue. However, the impact of healthy school environment on healthy eating habits among Asian adolescents is scarce and less clear. This clustered randomised-control study has two objectives. The first objective was to evaluate the changes in adolescents’ dietary intake after the interventions for all arms (control; healthy cooking training only; subsidization with healthy cooking training). The second objective was to compare the effect of subsidization with healthy cooking training and healthy cooking training only with the control arm on adolescents’ dietary intakes. This study consisted of 340 secondary school students aged 14 years in rural and urban Malaysia. A total of two arms of intervention and one arm of control were included. Intervention one focused on healthy cooking preparation for the canteen and convenience shop operators. Intervention two included subsidization for fruits and vegetables with a healthy cooking preparation training for the canteen and suggestions on providing healthy options to the convenience shop operators. The outcome measured was changes to dietary intake. It was measured using a three-day dietary history pre- and post-intervention. A paired-t test was used to evaluate the outcome of intervention programmes on dietary changes for all arms (control, intervention one and two). An ANCOVA test was used to investigate the effect of providing subsidization and healthy cooking preparation training to the canteen and convenience shop operators on adolescents’ dietary intakes as compared to the control arm. Overall, the reduction in energy and carbohydrates for all arms were observed. Interestingly, fat intake was significantly increased after the four-week intervention programme under healthy cooking intervention but not in the food subsidization group. When comparing between control, healthy cooking training only and subsidization with the healthy cooking training arm, there was no significant changes between arms. A robust intervention to include subsidization of healthy foods for intervention programmes at schools in a larger scale study is needed to confirm this finding. 相似文献
56.
Bisma Parveez Nur Ayuni Jamal Hazleen Anuar Yusilawati Ahmad Abdul Aabid Muneer Baig 《Materials》2022,15(15)
Metal foams possess remarkable properties, such as lightweight, high compressive strength, lower specific weight, high stiffness, and high energy absorption. These properties make them highly desirable for many engineering applications, including lightweight materials, energy-absorption devices for aerospace and automotive industries, etc. For such potential applications, it is essential to understand the mechanical behaviour of these foams. Producing metal foams is a highly challenging task due to the coexistence of solid, liquid, and gaseous phases at different temperatures. Although numerous techniques are available for producing metal foams, fabricating foamed metal still suffers from imperfections and inconsistencies. Thus, a good understanding of various processing techniques and properties of the resulting foams is essential to improve the foam quality. This review discussed the types of metal foams available in the market and their properties, providing an overview of the production techniques involved and the contribution of metal foams to various applications. This review also discussed the challenges in foam fabrications and proposed several solutions to address these problems. 相似文献
57.
PURPOSE: To study the prevalence of dry eye in a hospital-based population and to evaluate the various risk factors attributable to dry eye. MATERIALS AND METHODS: In this cross-sectional study, 500 patients above 20 years of age were screened randomly for dry eye. A 13-point questionnaire, Lissamine Green test, Tear film break-up time (TBUT), Schirmer's test and presence of strands/filaments were used to diagnose dry eye. The diagnosis was made when at least three of the tests were positive. The role of air pollution, sunlight, excessive winds, smoking, drugs and refractive status as dry eye risk factors was assessed. RESULTS: Ninety-two (18.4%) patients had dry eye. Dry eye prevalence was maximum in those above 70 years of age (36.1%) followed by the age group 31-40 years (20%). It was significantly higher (P = 0.024) in females (22.8%) than in males (14.9%), more common in rural residents (19.6%) than in urban (17.5%) and highest among farmers/labourers (25.3%). A 2.15 fold increase was found in the odds for dry eye in those exposed to excessive wind, 1.91 fold to sunlight exposure, 1.42 to smoking, 1.38 to air pollution and 2.04 for persons on drugs. Dry eye prevalence was 14% in emmetropes, 16.8% in myopes and 22.9% in hypermetropes. It was 15.6% in those with corrected and 25.3% in those with uncorrected refractive errors. CONCLUSION: Dry eye is an under-diagnosed ocular disorder. Reduction in the modifiable risk factors of dry eye is essential to reduce its prevalence. 相似文献
58.
Gin Gin GanKevin Wen Fei TeySumaiyah MatMarniza SaadPing Chong BeeRozita Abdul MalikGwo Fuang HoChong Guan Ng 《Asian Pacific journal of cancer prevention》2022,23(11):3905-3914
Background: Quality of life (QOL) of family caregivers of cancer patients is usually affected due to increase in caregiver burden. Their QOL has not garnered much attention by many including the health professionals and community. This study aims to explore the QOL of family caregivers of cancer patients in a multi-ethnic country in Asia and to investigate its associate factors. Methods: This is a cross-sectional study where family caregivers and patients who were diagnosed of cancers within 12 months were recruited. QOL of caregivers were measured using The Caregiver Quality of Life Index-Cancer (CQOLC). Psychological distress was measured using Hospital anxiety and depressive scale. Logistic regression analysis was performed to determine the related factors of QOL of caregivers. Results: A total of 458 patients/caregiver pairs were included. Symptoms of anxiety and depression reported by caregivers were 24.9% and 24.2% respectively. Caregivers of patients with solid tumors have better CQOLC score compared to those who cared for patients with hematological cancers (91.25 vs 86.75). Caregivers of non-Malay ethnicity, those caring for patients with advanced stage cancer and with hematological cancers had significantly poorer QOL. QOL of caregivers are also significantly affected when patients demonstrated anxiety symptoms. Conclusion: This study provides detailed evaluation of the QOL of caregivers of cancer patients in Malaysia. The significant psychological distress and low caregiver QOL indicate the urgent need for comprehensive supports for caregivers with cancer patients, especially those caring for patients with haematological cancers. 相似文献
59.
Dileep K Rohra Nirmal Das Syed I Azam Nazir A Solangi Zahida Memon Abdul M Shaikh Nusrat H Khan 《BMC pregnancy and childbirth》2008,8(1):1-5
Background
Low birth weight (LBW) is considered as a major multifaceted public health concern. Seventy-two percent of LBW infants are born in Asia. An estimation of 8% LBW infants has been reported for Eastern Mediterranean region including Iran. This study investigated contributory factors of LBW in singleton term births in Tehran, Iran. Tehran is a multicultural metropolitan area and a sample from the general population in Tehran could be regarded as a representative sample of urban population in Iran.Methods
This was a retrospective study using data from 15 university maternity hospitals in Tehran, Iran. Data on all singleton term births in these hospitals were extracted from case records during a one calendar year. Study variables included: maternal age, maternal educational level, history of LBW deliveries, history of preterm labor, cigarette smoking during pregnancy, number of parities, chronic diseases and residential area (Tehran versus suburbs of Tehran). In order to examine the relationship between LBW and demographic and reproductive variables the adjusted logistic regression analysis was performed.Results
In all, data for 3734 term pregnancies were extracted. The mean age of women was 25.7 (SD = 5.3) years and 5.2% of term births were LBW. In addition to association between LBW and maternal age, significant risk factors for LBW were: history of LBW deliveries [adjusted odds ratio (OR) = 2.53, 95% confidence interval (CI) = 1.06–6.03], smoking during pregnancy (OR = 4.64, 95% CI = 1.97–10.95) and chronic diseases (OR for hypertension = 3.70, 95% CI = 2.25–6.06, OR for others = 2.04, 95% CI = 1.09–3.83).Conclusion
The findings indicate that in addition to maternal age, history of LBW deliveries; smoking during pregnancy and chronic diseases are significant determinants of LBW in this population. This is consistent with national and international findings indicating that maternal variables and risk behaviors during pregnancy play important roles on LBW. 相似文献60.