全文获取类型
收费全文 | 3089篇 |
免费 | 223篇 |
国内免费 | 111篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 62篇 |
妇产科学 | 31篇 |
基础医学 | 321篇 |
口腔科学 | 76篇 |
临床医学 | 375篇 |
内科学 | 455篇 |
皮肤病学 | 35篇 |
神经病学 | 111篇 |
特种医学 | 121篇 |
外国民族医学 | 2篇 |
外科学 | 325篇 |
综合类 | 601篇 |
预防医学 | 205篇 |
眼科学 | 45篇 |
药学 | 253篇 |
1篇 | |
中国医学 | 143篇 |
肿瘤学 | 244篇 |
出版年
2023年 | 38篇 |
2022年 | 46篇 |
2021年 | 86篇 |
2020年 | 120篇 |
2019年 | 95篇 |
2018年 | 79篇 |
2017年 | 104篇 |
2016年 | 87篇 |
2015年 | 89篇 |
2014年 | 176篇 |
2013年 | 203篇 |
2012年 | 152篇 |
2011年 | 226篇 |
2010年 | 145篇 |
2009年 | 143篇 |
2008年 | 142篇 |
2007年 | 152篇 |
2006年 | 114篇 |
2005年 | 110篇 |
2004年 | 101篇 |
2003年 | 91篇 |
2002年 | 90篇 |
2001年 | 81篇 |
2000年 | 104篇 |
1999年 | 91篇 |
1998年 | 56篇 |
1997年 | 57篇 |
1996年 | 45篇 |
1995年 | 35篇 |
1994年 | 39篇 |
1993年 | 25篇 |
1992年 | 25篇 |
1991年 | 27篇 |
1990年 | 22篇 |
1989年 | 16篇 |
1988年 | 13篇 |
1987年 | 15篇 |
1986年 | 14篇 |
1985年 | 40篇 |
1984年 | 16篇 |
1983年 | 15篇 |
1982年 | 23篇 |
1981年 | 19篇 |
1980年 | 19篇 |
1979年 | 10篇 |
1978年 | 11篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1975年 | 2篇 |
1973年 | 2篇 |
排序方式: 共有3423条查询结果,搜索用时 17 毫秒
1.
Plant protection products may affect the behavior of organisms which are not a target of control. The effect of Karate Zeon 050 CS (λ-Cyhalothrin -based insecticide; λ-CBI) and Amistar 250 SC (Azoxystrobin-based fungicide; ABF) was determined on Apis mellifera worker attraction towards their own colony odour, along with temperature preferences. Bees exposed to pesticides prefer the environment with the odour of their nest less often than the control group, and that insecticide-treated bees chose warmer environments than the control insects. The observed differences in the bees, especially with attraction towards their own colony, were dependent on the time of day. Chromatographic analyses indicated that λ-Cyhalothrin elimination was half that of Azoxystrobin in bee organisms, and both agents retarded each other’s clearance. Mathematical modeling estimated that despite a relatively high disappearance rate, both compounds might have been bio-accumulated at relatively high level. 相似文献
2.
《Gait & posture》2022
BackgroundHigh injury rates following anterior cruciate ligament reconstruction (ACLR) motivate the need to better understand lingering movement deficiencies following return to sport. Athletic competition involves various types of sensory, motor, and cognitive challenges; however, postural control deficiencies during this spectrum of conditions are not well understood following ACLR.Research questionTo what extent is postural control altered following ACLR in the presence of sensory, motor, and cognitive challenges, and does postural control correlate with patient-reported symptoms?MethodsFourteen individuals following ACLR (4 m/10 f, 21.2 ± 2.4 yr, 76.9 ± 19.1 kg, 1.70 ± 0.14 m) and fourteen matched healthy controls (4 m/10 f, 21.2 ± 1.4 yr, 75.4 ± 15.3 kg, 1.70 ± 0.15 m) participated in the study. Participants completed single-leg balance, ACLR limb or matched side for controls, under four conditions: 1) eyes open, 2) eyes closed, 3) visual-cognitive dual task (i.e., reverse digit span), and 4) motor dual task (i.e., catching a ball). Sample entropy (SEn) was calculated for each balance condition to characterize regularity of center of pressure control. Participants also completed patient-reported outcomes to characterize self-reported knee function, symptoms, and fear. A mixed effects model tested for differences in SEn between balance conditions, and Spearman correlations tested for relationships between SEn and patient-reported outcomes.ResultsA significant Group-by-Condition interaction was detected (P = 0.043). While the motor dual task and eyes closed balance conditions were associated with the lowest SEn for both groups, only the visual-cognitive dual task condition demonstrated a significant difference between groups, with the ACLR group having lower SEn [95% confidence interval for ΔSEn: (0.03, 0.35)]. Lower KOOS-Sport scores were associated with decreased SEn for the ACLR group (ρ = 0.81, P < 0.001).SignificanceThese findings are consistent with ACLR individuals using a less automatic approach to postural control compared to controls, particularly when presented with a visual-cognitive challenge. Altered neuromuscular control persists well after ACLR surgery and can be related to patient-reported outcomes. 相似文献
3.
《HPB : the official journal of the International Hepato Pancreato Biliary Association》2022,24(10):1780-1788
BackgroundWe assessed whether or not covalently closed circular DNA (cccDNA) levels in the background liver influence the recurrence of hepatocellular carcinoma (HCC) in patients with resolved hepatitis B virus (HBV) infection.MethodsAmong 425 patients who underwent initial hepatectomy for HCC between 2010 and 2018, a retrospective review was performed in 44 with resolved HBV infection. The clinicopathologic characteristics were analyzed for correlation with tumor recurrence. The HBV cccDNA levels were tested via a droplet digital polymerase chain reaction assay.ResultsHBV cccDNA was detected in 27 of 44 patients (61%), and the median level was 1.0 copies/1000 ng (range, 0-931.3 copies/1000 ng). Anti-HBc ≥8.9 S/CO was associated with cccDNA detection (odds ratio, 11.08; 95% confidence interval [95% CI], 2.48-49.46; P = 0.002). Twenty-eight patients (64%) developed HCC recurrence after hepatectomy. The overall 3- and 5-year recurrence-free survival rates were 45.7% and 34.3%, respectively.19 HBV cccDNA levels was not significantly associated with HCC recurrence, while the presence of multiple tumors was an independent risk fact or (hazard ratio, 6.53; 95% CI, 2.48-17.19; P < 0.001.ConclusionHBV cccDNA levels did not influence HCC recurrence after hepatectomy. Anti-HBc levels may be used as a surrogate marker for cccDNA. 相似文献
4.
Bartosz Slomka Witold Rongies Janusz Sierdzinski Wlodzimierz Dolecki Marta Worwag Ewa Trzepla 《Acta orthopaedica et traumatologica turcica》2019,53(1)
Objective
The aim of the study was to assessment the impact of hip osteoarthritis on postural stability.Methods
One hundred and twenty-five randomly selected women 20–85 years old (mean age of 49 ± 24.4 years) were assigned to three groups based on age, health status and activity level. Group 1 (cases) – elderly women with diagnosed hip osteoarthritis, group 2 (control) - women without hip osteoarthritis, and group 3 (control) - healthy young women. Assessment of postural stability were measured using a WIN-POD Pel 38 electronic podometer. Statistica 10 software was used to perform t-test resulting in significance level of p < 0.05.Results
Significant differences in pedobarographic balance measurements were observed between the study groups with eyes opened or closed (deviation length eyes open: group 1–3 and 2–3 p < 0.0001; eyes closed group 1–2 p = 0.19; 1–3 and 2–3 p < 0.0001; deviation area eyes open: group 1-3 and 2–3 p < 0.0001; eyes closed group 1–3 and 2–3 p < 0.0001; deviation velocity eyes open: group1-3 and 2–3 p < 0.0001; eyes closed group 1–2 p < 0.010, 1–3 and 2–3 p < 0.0001). The poorest postural stability was observed in patients with hip osteoarthritis (deviation length eyes open vs eyes closed 180.8/201.7 p = 0.028, deviation area 128.7/145.7 p = 0.771, deviation velocity 5.1/6.1 p < 0.0001), and the best postural stability was observed in young women (deviation length 111.3/137.5 p < 0.0001, deviation area 57/76.9 p = 0.003, deviation velocity 3.4/4.2 p < 0.0001).Conclusion
(1) Osteoarthritic degeneration of the hip joint results in a significant disturbance in proprioception. This finding was reflected by the inferior stability parameters collected from subjects with hip osteoarthritis when asked to stand with their eyes closed. These finding were not observed in the other groups. (2) The disorder of the body stability of people with osteoarthritis may be a relative indication for the implantation of hip arthroplasty. 相似文献5.
6.
Meenakshi Bamnia 《Toxin reviews》2015,34(3):119-124
Emetic and diarrheal toxins produced by endospore-forming Bacillus cereus causes a huge loss to dairy industry. Milk is the suitable medium for the growth of B. cereus. The pathogen is of particular concern in the dairy industry because in spite of aggressive cleaning practices performed by the dairy industry, it is impossible to destroy these hydrophobic spores which adhere to the pipelines of the dairy-processing plant and further these spores may also form biofilms in the milk. The reporting rate of illness caused by B. cereus is vague, usually due to the short duration of (<24?h) the diarrheal and emetic syndromes. The study of toxins production by B. cereus isolates is essential to better determine the methods of controlling these toxins in dairy industry. 相似文献
7.
《Indian journal of medical microbiology》2020,38(2):216-218
Staphylococcus aureus and other Gram negative bacteria produce small colony variants (SCV) which usually emerge after exposure to antimicrobials. They cause repeated infections, treatment failures and often pass unnoticed during cultures due to unusual appearance and incomplete incubation. This infectious disease grand round highlights a similar clinical case with atypical history and appearance of a SCV of S. aureus and why prolonged incubation is necessary for aspirates from patients with recurrent infections like abscesses. 相似文献
8.
《Anaesthesia and Intensive Care Medicine》2022,23(9):553-560
Neuropathic pain is a well-recognized chronic pain condition. This can have a significant impact on patients' quality of life. Neuromodulation is defined by the International Neuromodulation Society as ‘the therapeutic alteration of activity in the central or peripheral nervous system either electrically or pharmacologically’. Electrical stimulation can be performed at the motor cortex, deep brain, spinal cord, dorsal root ganglion, peripheral nerve and peripheral nerve field. Pharmacological modulation is achieved by directly infusing drugs to the central nervous system. Although neuromodulation has become increasing popular, it is still currently believed to be underused in treating neuropathic pain. This modality has provided us with a non-pharmacological approach to manage patients with neuropathic pain. Patients should have been assessed by a multidisciplinary team before undergoing neuromodulation. This review highlights the present and future management of patients with chronic intractable pain using neuromodulation. 相似文献
9.
10.