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11.
12.
本实验就复方硅橡胶栓堵剂(CSR)对家兔输卵管上皮细胞趋微结构的影响进行了观察分析,并测定了上皮细胞内铜元素的含量变化,电镜观察表明:家充输卵管经复方硅橡胶栓堵后,其上皮细胞表面结构、细胞连接、细胞核等超微结构均未发生明显的形态改变:注药侧(右侧〕和对照侧(左侧)输卵管上皮细胞内虽有少数线粒体膨胀,但两组间无论在线粒体数目,膨胀线粒体百分率以及线粒体外膜比表面等方面均无差异(P>0.1),电镜X—时线能谱分析表明:注药侧输卵管上皮细胞内铜元素的相对含量咯高于对照组,而且铜元素多畜集于线粒体内。 相似文献
13.
Therapeutic and management challenges in Wilson's disease 总被引:1,自引:0,他引:1
ASHISH BAVDEKAR 《Journal of gastroenterology and hepatology》2004,19(S7):S391-S395
Abstract Wilson's disease, an inborn error of copper metabolism, is an important cause of liver disease in India. A high index of suspicion is necessary for diagnosis as it can have a varied clinical presentation (e.g. all forms of acute and chronic liver disease, minimal to severe neurological disease, bony deformities, hemolytic anemia). Hepatic copper estimation is the most reliable diagnostic test, but is not easily available in India. In the absence of hepatic copper, a low ceruloplasmin, high 24 h urinary copper and presence of KF rings aid in making the diagnosis (at least two of these). Life-long therapy is necessary with D-Penicillamine, Trientine or zinc. Though response to therapy may be unpredictable, acute and early presentations such as fulminant hepatic failure have a poor outcome without liver transplantation. The siblings of all cases must be screened, as early diagnosis and treatment results in a good outcome. The identification of the Wilson's disease gene on chromosome 13 has led to the possible use of molecular genetics (haplotype and mutational analyses) in the diagnosis of the disease. 相似文献
14.
Kristen E. Stevens Julienne E. Price Jamie Marko Stephen G. Kaler 《American journal of medical genetics. Part A》2020,182(6):1364-1377
Classic Menkes disease is a rare X‐linked recessive disorder of copper metabolism caused by pathogenic variants in the copper transporter gene, ATP7A. Untreated affected individuals suffer failure to thrive and neurodevelopmental delays that begin at 6–8 weeks of age and progress inexorably to death, often within 3 years. Subcutaneous injections of Copper Histidinate (US Food and Drug Administration IND #34,166, Orphan product designation #12‐3663) are associated with improved survival and neurological outcomes, especially when commenced within a month of birth. We previously identified internal jugular vein phlebectasia (IJP) in four Menkes disease subjects. This feature and other connective tissue abnormalities appear to be consequences of deficient activity of lysyl oxidase, a copper‐dependent enzyme. Here, we report results from a prospective study of IJP based on 178 neck ultrasounds in 66 Menkes subjects obtained between November 2007 and March 2018. Nine patients met the criterion for IJP (one or more cross‐sectional area measurements exceeding 2.2 cm2) and five subjects had clinically apparent neck masses that enlarged over time. Our prospective results suggest that IJP occurs in approximately 14% (9/66) of Menkes disease patients and appears to be clinically benign with no specific medical or surgical actionability. We surveyed the medical literature for prior reports of IJP in pediatric subjects and identified 85 individuals and reviewed the distribution of this abnormality by gender, sidedness, and underlying etiology. Taken together, Menkes disease accounts for 16% (15/94) of all reported IJP individuals. Neck masses from IJP represent underappreciated abnormalities in Menkes disease. 相似文献
15.
Schweigert N Acero JL von Gunten U Canonica S Zehnder AJ Eggen RI 《Environmental and molecular mutagenesis》2000,36(1):5-12
Free hydroxyl radicals (free (.)OH), singlet oxygen ((1)O(2)), or (. )OH produced by DNA-copper-hydroperoxo complexes are possible DNA-damaging reactive oxygen species (ROS) in the reaction system containing copper, catechol, and DNA. para-Chlorobenzoic acid (pCBA) degradation studies revealed that CuCl(2) mixed with catechol produced free (.)OH. In the presence of DNA, however, inhibition of the pCBA degradation suggested that another ROS is responsible for the DNA degradation. Of a series of ROS scavengers investigated, only KI, NaN(3), and Na-formate-all of the salts tested-strongly inhibited the DNA degradation, suggesting that the ionic strength rather than the reactivity of the individual scavengers could be responsible for the observed inhibition. The ionic strength effect was confirmed by increasing the concentration of phosphate buffer, which is a poor (.)OH scavenger, and was interpreted as the result of destabilization of DNA-copper-hydroperoxo complexes. Piperidine-labile site patterns in DNA degraded by copper and catechol showed that the mixture of Cu(II) and catechol degrades DNA via the intermediate formation of a DNA-copper-hydroperoxo complex. Replacement of guanine by 7-deazaguanine did not retard the DNA degradation, suggesting that the DNA-copper-hydroperoxo complexes do not bind to the guanine N-7 as proposed in the literature. 相似文献
16.
Yuxiang Ma Daxian Zhang Teruyuki Kawabata Takahiro Kiriu Shinya Toyokuni Koji Uchida Shigeru Okada 《Pathology international》1997,47(4):203-208
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls 相似文献
17.
Mzhel'skaya TI 《Bulletin of experimental biology and medicine》2000,130(8):719-727
Ceruloplasmin, a multicopper ferroxidase, is involved in iron and copper homeostasis and integrates these metabolic pathways.
Impaired biosynthesis of ceruloplasmin caused by gene mutations disturbs iron metabolism with iron deposition in different
organs, especially in the basal ganglia, and severe neuronal damage. Dysfunction of ATP7B, a copper-transporting ATPase leads
to the development of Wilson’s disease,i.e., multiple abnormalities in copper metabolism associated with reduced synthesis of holoceruloplasmin and biliary copper excretion
controlled by both proteins. The lowest content of serum ceruloplasmin is observed in the most grave early neurological form
of Wilson’s disease (according to N. V. Konovalov’s classification), which confirms the important role of ceruloplasmin in
the striatal metabolism of catecholamines.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 124–133, August, 2000 相似文献
18.
作者从研究中发现:用Roberts铜盐法测定蔗汁样本葡聚糖含量时,所得结果与蔗汁的受热有关,受热蔗汁的测定值高于真实值,作者将这种现象暂称为Roberts铜盐法测定蔗汁样本葡聚糖含量的热效应。研究表明:蔗汁中的淀粉是引起热效应的重要因素。本文最后提出了一种由淀粉引起的热效应的可行校正方法。 相似文献
19.
Katarzyna Socha Katarzyna Klimiuk Sylwia K. Naliwajko Jolanta Soroczyska Anna Pucion-Jakubik Renata Markiewicz-ukowska Jan Kochanowicz 《Nutrients》2021,13(2)
Oxidative stress plays a crucial role in the neurodegenerative process and can impair cognitive functions. In the prevention of Alzheimer’s disease (AD), an adequate consumption of dietary antioxidants may be a major factor. The objective of the study was to estimate selenium (Se), copper (Cu), zinc (Zn), and total antioxidant status (TAS) in the serum of patients with AD in relation to their cognitive functions and dietary habits. A total of 110 patients (aged 54–93 years) with early or moderate AD, as well as 60 healthy people (aged 52–83 years) were studied. The severity of the disease was assessed using the mini-mental state examination (MMSE) scale. Food-frequency questionnaires were implemented to collect the dietary data. The concentrations of Se, Cu and Zn in the sera were determined by the atomic absorption spectrometry method. TAS was estimated spectrophotometrically using ready-made kits (Randox). Significantly lower concentrations of Se, Zn and TAS, and higher Cu:Zn ratio in the serum of patients with AD, compared to healthy people, were observed. A low correlation between the MMSE score and TAS in the serum of AD patients and significantly higher MMSE values in patients with TAS above the reference range were also noted. In patients with serum Cu concentration above the norm, significantly lower MMSE values were found. Selected dietary habits such as the frequency of consumption of various food products had a significant impact on the concentration of the assessed parameters in the serum of people with AD. 相似文献
20.
SD雄性大鼠45只,随机分为对照组,运动组和运动补锌组,运动各组进行跑台跑步,各按不同的运动小组,分别在第4,6,8,10天跑步至力竭后,立即处死,按要求取骨骼肌,血清以测定微量元素铜含量,结果显示铜含量在对照组的骨骼肌,血清中与各运动,运动补锌小组没有明显差异,表明力竭跑10天对铜含量无明显影响。 相似文献