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991.
992.
Binhao Zhang Bixiang Zhang Zhiwei Zhang Zhiyong Huang Yifa Chen Minshan Chen Ping Bie Baogang Peng Liqun Wu Zhiming Wang Bo Li Jia Fan Lunxiu Qin Ping Chen Jingfeng Liu Zhe Tang Jun Niu Xinmin Yin Deyu Li Songqing He Bin Jiang Yilei Mao Weiping Zhou Xiaoping Chen 《中国科学:生命科学英文版》2018,(6)
Hepatectomy is currently routinely performed in most hospitals in China. China owns the largest population of liver diseases and the biggest number of liver resection cases. A nationwide multicenter retrospective investigation involving 112 hospitals was performed, and focused on liver resection for patients with hepatocellular carcinoma(HCC). 42,573 cases of hepatectomy were enrolled, and 18,275 valid cases of liver resection for HCC patients were selected for statistical analysis. The epidemiology of HCC, distribution of hepatectomy, postoperative complications and prognosis were finally analyzed. In the 18,275 HCC patients,81% had hepatitis B virus infection and 10% had hepatitis C virus infection. 38% of the HCC patients had normal Alphafetoprotein(AFP) level, and other 35% had an AFP level lower than 400 ng mL~(-1). In the study period, 97% of the hepatectomy for HCC were treated with open surgery, and 23.81% had vascular exclusion techniques. The operation time was(191.7±105.6) min,the blood loss was(546.0±562.8) m L, and blood transfusion was(543.0±1,035.2) m L. The median survival for HCC patients was 631 days, with 1-, 3-, and 5-year overall survival of 73.2%, 28.8% and 19.6%, respectively. Liver cirrhosis, multiple nodules,tumor thrombosis and high AFP level were risk factors that affect postoperative survival. 相似文献
993.
Whole‐field macro‐ and micro‐deformation characteristic of unbound water‐loss in dentin hard tissue 下载免费PDF全文
Zhenning Chen Bobby Nadeau Kevin Yu Xinxing Shao Xiaoyuan He M. Cynthia Goh Anil Kishen 《Journal of biophotonics》2018,11(9)
High‐resolution deformation measurements in a functionally graded hard tissue such as human dentin are essential to understand the unbound water‐loss mediated changes and their role in its mechanical integrity. Yet a whole‐field, 3‐dimensional (3D) measurement and characterization of fully hydrated dentin in both macro‐ and micro‐scales remain to be a challenge. This study was conducted in 2 stages. In stage‐1, a stereo‐digital image correlation approach was utilized to determine the water‐loss and load‐induced 3D deformations of teeth in a sagittal section over consecutively acquired frames, from a fully hydrated state to nonhydrated conditions for a period up to 2 hours. The macroscale analysis revealed concentrated residual deformations at the dentin‐enamel‐junction and the apical regions of root in the direction perpendicular to the dentinal tubules. Significant difference in the localized deformation characteristics was observed between the inner and outer aspects of the root dentin. During quasi‐static loadings, further increase in the residual deformation was observed in the dentin. In stage‐2, dentin microstructural variations induced by dynamic water‐loss were assessed with environmental scanning electron microscopy and atomic force microscopy (AFM), showing that the dynamic water‐loss induced distention of dentinal tubules with concave tubular edges, and concurrent contraction of intertubular dentin with convex profile. The findings from the current macro‐ and micro‐scale analysis provided insight on the free‐water‐loss induced regional deformations and ultrastructural changes in human dentin. 相似文献
994.
Regulation of fibroblast growth factor 8 (FGF8) in chicken embryonic stem cells differentiation into spermatogonial stem cells 下载免费PDF全文
995.
Occurrences of harmful algal blooms (HABs) associated with ocean environments in the South China Sea 总被引:2,自引:0,他引:2
SuFen Wang DanLing Tang FangLiang He Yasuwo Fukuyo Rhodora V. Azanza 《Hydrobiologia》2008,596(1):79-93
Harmful algal blooms (HABs) occur frequently in the South China Sea (SCS), causing enormous economic losses in aquaculture.
We analyzed historical HAB records during the period from 1980 to 2003 in SCS. We found that HABs-affected areas have expanded
and the frequency of HABs varied during this period. The seasonal and annual variations, as well as causative algal species
of HABs are different among the four regions. Areas with frequent HABs include the Pearl River Estuary (China), the Manila
Bay (the Philippines), the Masinloc Bay (the Philippines), and the western coast of Sabah (Malaysia). HABs occurred frequently
during March–May in the northern region of SCS, May–July in the eastern region, July in the western region, and year-round
in the southern region. Among the species that cause HABs, Noctiluca scintillans dominated in the northern region, and Pyrodinium bahamense in the southern and eastern regions. Causative species also varied in different years for the entire SCS. Both P. bahamense and N. scintillans were the dominant species during 1980–2003. Some species not previously recorded formed blooms during 1991–2003, including
Phaeocystis globosa, Scrippsiella trochoidea, Heterosigma akashiwo, and Mesodinium rubrum. Variations in HABs are related to various regional conditions, such as a reversed monsoon wind in the entire SCS, river
discharges in the northern area, upwelling in Vietnam coastal waters during southwest winds and near Malaysia coastal waters
during northeast winds, and eutrophication from coastal aquaculture in the Pearl River estuary, Manila Bay, and Masinloc Bay.
Handling editor: D. Hamilton 相似文献
996.
Molecular mechanism of feedback regulation of 17β‐estradiol on two kiss genes in the protogynous orange‐spotted grouper (Epinephelus coioides) 下载免费PDF全文
997.
998.
Xiaobing Liu Jianhua Piao Yu Zhang Yuna He Weidong Li Lichen Yang Xiaoguang Yang 《Biological trace element research》2017,178(2):194-200
Zinc is an essential trace element for growth and development in children, but zinc deficiency is a serious nutritional problem worldwide. Our study aimed to assess the zinc status of school-age children living in rural areas of China and to examine the change of zinc status based on the China Nutrition and Health Survey 2002 and 2012. We used the probability proportional to size sampling method for subject selection, and a total of 3407 school-age children were included in this study. Zinc status was assessed by three items of indicators recommended by the World Health Organization (WHO), the United Nations Children’s Fund (UNICEF), the International Atomic Energy Agency (IAEA), and the International Zinc Nutrition Consultative Group (IZiNCG). The concentration of serum zinc was 718.2 μg/L, and 44.4% of children being zinc deficiency in 2002, while 846.8 μg/L and 10.4% in 2012. Zinc intake was 7.8 mg/day with a 7.6% inadequate zinc intake in 2002, together with 6.9 mg/day and 38.2% in 2012. Height-for-age Z score was ?1.06 and 19.1% of children being stunting in 2002, as well as ?0.15 and 6.8% in 2012. In conclusion, the zinc status of school-age children living in rural areas of China has been significantly improved in addition to zinc intake over the past 10 years. However, the zinc deficiency still observed in poor rural areas of China in 2012. In addition, we suggested that the zinc bioavailability should be taken into account when assessing zinc status in population. 相似文献
999.
Iodine and iron are essential elements for healthy thyroid function. However, little is known about the association of iron and iodine with thyroid function in the general US population. We investigated iron and iodine status in relation to concentrations of thyroid hormones. We included 7672 participants aged 20 and older from three surveys (2007–2008, 2009–2010, and 2011–2012) of the National Health and Nutrition Examination Survey. Serum thyroid measures (including free and total T3 and T4, and TSH), serum iron concentration, and urinary iodine concentrations were measured. Multivariate linear regression models were conducted with serum thyroid measures as dependent variables and combinations of serum iron concentration and urinary iodine concentration as predictors with covariate adjustment. Logistic regression models were performed with TSH levels (low, normal, and high) and combinations of serum iron concentration and urinary iodine concentration. Overall, 10.9% of the study population had low iron; 32.2 and 18.8% had low or high iodine levels, respectively. Compared with normal levels of iron and iodine, normal iron and high iodine were associated with reduced free T3 and increased risk of abnormal high TSH. Combined low iron and low iodine was associated with reduced free T3 and increased TSH. In addition, high iodine was associated with increased risk of abnormal high TSH in females but not in males. Thyroid function may be disrupted by low levels of iron or abnormal iodine, and relationships are complex and sex-specific. Large prospective studies are needed to understand the mechanisms by which iron interacts with iodine on thyroid function. 相似文献
1000.
Luhong Zhou He Li Haihua Shen Yunping Xu Yinghui Wang Aijun Xing Jingyun Fang 《Biogeochemistry》2017,136(3):311-324
Shrub encroachment frequently occurs in arid and semi-arid grasslands worldwide and affects the regional carbon balance. Many previous studies have revealed the effects of shrub encroachment on bulk carbon content of grasslands, but molecular evidence is surprisingly lacking. In this study, we examined the chemical composition of plant tissues and soil organic carbon (SOC), and soil microbial communities to identify the effects of shrub (Caragana microphylla) encroachment on SOC storage in the top layer (0–10 cm) along a gradient of natural shrub cover in the grasslands of Inner Mongolia. We found that SOC in the shrub patches was derived mainly from leaves, whereas SOC in the grassy matrix was composed of a mixture of fresh root- and leaf-derived compounds. Compared with pure grassland, the SOC decreased by 29% in the shrub-encroached grasslands (SEGs), and this decrease was enhanced by increasing shrub cover. We also found that free lipids and lignin-derived phenols increased while the ratios of ω-C18/∑C18 and suberin/cutin decreased with increasing shrub cover. In addition, the ratios of fungal to bacterial phospholipid fatty acids (PLFAs) and gram-negative to gram-positive bacterial PLFAs decreased with increasing shrub cover. These results indicate that the encroachment of nitrogen-rich legume shrubs can lead to carbon loss by altering the chemical composition of plant inputs as well as the soil microbial community in grassland ecosystems. 相似文献