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91.
同型半胱氨酸对大鼠血管平滑肌细胞增殖的作用 总被引:11,自引:0,他引:11
血中同型半胱氨酸(homocysteine,HCY)浓度的升高已成为动脉粥样硬化发生的一个独立危险因子.为进一步阐明HCY促进血管平滑肌细胞(vascularsmoothmusclecels,VSMCs)增殖,从而引起动脉粥样硬化发生的机理.本实验采用细胞计数、3H-TdR参入、细胞周期分析、Northern杂交方法证明,一定剂量的HCY可促进离体培养的WKY大鼠血管平滑肌细胞增殖,使其DNA合成增加,细胞周期中S期细胞所占比例增加43%,并促进c-myc与c-fos原癌基因mRNA表达增加.提示HCY可能通过促进VSMCs增殖而诱发动脉粥样硬化 相似文献
92.
免疫毒素Luffin B-Ng76对人黑色素瘤细胞的体外抑制作用 总被引:7,自引:0,他引:7
用BlueSepharoseCL-6B凝胶亲和层析法从丝瓜籽中分离纯化了单链致核糖体失活蛋白(ribosomeinac-tivatingprotein,RIP)——lufinB。并将lufinB与抗人黑色素瘤细胞单抗Ng76制成了免疫毒素,命名为lufinB-Ng76,它对体外培养的黑色素瘤细胞M21有很强的抑制作用,IC50为2.5×10-11mol/L,毒性比游离的lufinB提高4000倍,而它对非靶的HeLa细胞的毒性较M21细胞低1200倍。结果提示lufinB用于制备免疫毒素具有良好的应用前景。 相似文献
93.
You‐Min Ying Cui‐Yu Li Yan Chen Jia‐Gui Xiang Ling Fang Jian‐Biao Yao Fa‐Song Wang Ru‐Wei Wang Wei‐Guang Shan Zha‐Jun Zhan 《化学与生物多样性》2015,12(8):1222-1228
Two new triterpenoids, 30‐hydroxylup‐20(29)‐ene 3β‐caffeate ( 1 ) and 24‐nor‐friedelan‐6α,10‐dihydroxy‐1,2‐dioxo‐4,7‐dien‐29‐oic acid ( 2 ), together with eight known compounds 3 – 10 , were isolated from the roots of Celastrus stylosus. The structures of these compounds were elucidated on the basis of spectroscopic analyses. To the best of our knowledge, this represents the first study on the chemical constituents of C. stylosus. The antiproliferative activities of the triterpenoids against six human cancer cell lines (PANC‐1, A549, PC‐3, HepG2, SGC‐7901, and HCCLM3) were evaluated. Compounds 3, 4 , and 10 exhibited comparable activities against PC‐3 and HCCLM3 cell lines as the positive control taxol. 相似文献
94.
Ting Hu Xiong Li Qinghua Zhang Kecheng Huang Yao Jia Ru Yang Fangxu Tang Qiang Tian Ding Ma Shuang Li 《PloS one》2015,10(4)
Background
The effect of neoadjuvant chemotherapy (NACT) on topographical distribution patterns of lymph node metastasis in cervical cancer was unknown.Methods
Patients with FIGO stage IB1-IIB who underwent radical surgery with or without NACT were enrolled (3527 patients). A matched-case comparison design was used to compare the effects of NACT on lymph node metastasis.Results
We analyzed groups of 167 and 140 patients who were diagnosed with lymph node metastasis in the matched primary surgery group and NACT group, respectively, and no significant difference was observed (p = 0.081). The incidence of lymph node metastasis was significantly decreased in the NACT-responsive group compared to the non-responsive group (18.4% vs. 38.6%, P<0.001). The metastatic rates for every lymph node group also declined in the NACT-responsive group except for the deep inguinal and the para-aortic lymph node groups. Clinical response, deep stromal, parametrial and lymph vascular invasions were independent risk factors for lymph node metastasis in the NACT group. Furthermore, deep stromal invasion and lymph vascular invasion, but not the response to NACT, were independently associated with upper LNM. The number of lymph nodes involved, response to NACT, tumor histology and a positive vaginal margin were independent prognostic factors affecting DFS or OS rates in node-positive patients treated with NACT plus radical surgery.Conclusion
The frequency and topographic distribution of LNM are not modified by NACT, and clinical non-responders showed more involved LNs. A systemic and extensive lymphadenectomy should be performed in patients treated with NACT plus surgery regardless of the response to NACT. 相似文献95.
María F. Garcés Elizabeth Sanchez Luisa F. Cardona Elkin L. Simanca Iván González Luis G. Leal José A. Mora Andrés Bedoya Juan P. Alzate ángel Y. Sánchez Javier H. Eslava-Schmalbach Roberto Franco-Vega Mario O. Parra Ariel I. Ruíz—Parra Carlos Diéguez Rubén Nogueiras Jorge E. Caminos 《PloS one》2015,10(6)
Background
Meteorin (METRN) is a recently described neutrophic factor with angiogenic properties. This is a nested case-control study in a longitudinal cohort study that describes the serum profile of METRN during different periods of gestation in healthy and preeclamptic pregnant women. Moreover, we explore the possible application of METRN as a biomarker.Methods and Findings
Serum METRN was measured by ELISA in a longitudinal prospective cohort study in 37 healthy pregnant women, 16 mild preeclamptic women, and 20 healthy non-pregnant women during the menstrual cycle with the aim of assessing serum METRN levels and its correlations with other metabolic parameters. Immunostaining for METRN protein was performed in placenta. A multivariate logistic regression model was proposed and a classifier model was formulated for predicting preeclampsia in early and middle pregnancy. The performance in classification was evaluated using measures such as sensitivity, specificity, and the receiver operating characteristic (ROC) curve. In healthy pregnant women, serum METRN levels were significantly elevated in early pregnancy compared to middle and late pregnancy. METRN levels are significantly lower only in early pregnancy in preeclamptic women when compared to healthy pregnant women. Decision trees that did not include METRN levels in the first trimester had a reduced sensitivity of 56% in the detection of preeclamptic women, compared to a sensitivity of 69% when METRN was included.Conclusions
The joint measurements of circulating METRN levels in the first trimester and systolic blood pressure and weight in the second trimester significantly increase the probabilities of predicting preeclampsia. 相似文献96.
Xiao-meng Xu Guang-yan Cai Ru Bu Wen-juan Wang Xue-yuan Bai Xue-feng Sun Xiang-mei Chen 《PloS one》2015,10(12)
Background
Numerous studies have demonstrated the life-extending effect of caloric restriction. It is generally accepted that caloric restriction has health benefits, such as prolonging lifespan and delaying the onset and progression of CKD in various species, especially in rodent models. Although many studies have tested the efficacy of caloric restriction, no complete quantitative analysis of the potential beneficial effects of reducing caloric intake on the development and progression of CKD has been published.Methods
All studies regarding the relationship between caloric restriction and chronic kidney diseases were searched in electronic databases, including PubMed/MEDLINE, EMBASE, Science Citation Index (SCI), OVID evidence-based medicine, Chinese Bio-medical Literature and Chinese science and technology periodicals (CNKI, VIP, and Wan Fang). The pooled odds ratios (OR) and 95% confidence intervals (95% CI) were calculated by using fixed- or random-effects models.Results
The data from 27 of all the studies mentioned above was used in the Meta analysis. Through the meta-analysis, we found that the parameter of blood urea nitrogen, serum creatinine and urinary protein levels of the AL group was significant higher than that of the CR group, which are 4.11 mg/dl, 0.08mg/dl and 33.20mg/kg/24h, respectively. The incidence of the nephropathy in the caloric restriction (CR) group was significantly lower than that in the ad libitum—fed (AL) group. We further introduced the subgroup analysis and found that the effect of caloric restriction on the occurrence of kidney disease was only significant with prolonged intervention; the beneficial effects of CR on the 60%-caloric-restriction group were greater than on the less-than-60%-caloric-restriction group, and caloric restriction did not show obvious protective effects in genetically modified strains. Moreover, survival rate of the caloric restriction group is much higher than that of the ad libitum—fed (AL) group.Conclusions
Our findings demonstrate for the first time that compared with the AL group, the caloric restriction indeed decreased urea nitrogen, creatinine, urine protein, incidence of kidney diseases and increased the survival rate on 700~800 days. 相似文献97.
Objective
This study aimed to determine the optimal Foley catheter balloon volume (30-mL vs. 80-mL) and the maximum time for cervical ripening (12 hours vs. 24 hours) to improve vaginal delivery rate within 24 hours of induction.Methods
We conducted an open-label, randomized controlled trial in a teaching hospital in China. Women with a term singleton pregnancy, cephalic presentation, intact membrane and an unfavorable cervix (Bishop score <6) were randomly allocated, in 1:1:1:1 ratio, to receive either one of the four treatments: (1) 30-mL balloon for a maximum of 12 hours, (2) 30-mL balloon for a maximum of 24 hours, (3) 80-mL balloon for a maximum of 12 hours, and (4) 80-mL balloon for a maximum of 24 hours. The primary outcome was vaginal delivery within 24 hours. Secondary outcomes included cesarean section rate and maternal/neonatal morbidity. Data were analyzed on a per-protocol basis.Results
Five hundred and four women were recruited and randomized (126 women in each group); nine women did not receive the assigned intervention. More women achieved vaginal delivery within 24 hours in 12-hour Foley catheter groups than in the 24-hour Foley catheter groups (30-mL/12 hours: 54.5%, 30-mL/24 hours: 33.1%, 80-mL/12 hours: 46.4%, 80-mL/24 hours: 24.0%, p < 0.001). Cesarean section rates and the incidence of chorioaminonitis were comparable among four groups. After adjustment for confounding factors, both ripening time and balloon size did not affect the proportion of women delivered vaginally within 24 hours of induction.Conclusion
For women with an unfavorable cervix at term, induction of labor with a Foley catheter is safe and effective. Higher balloon volume (80-mL vs. 30-mL) and longer ripening time (24 hours vs. 12 hours) would not shorten induction to delivery interval or reduce cesarean section rate.Trial Registration
Chinese Clinical trial registry (ChiCTR-TRC-13003044) 相似文献98.
99.
Zhang Yong Xia Qin Jian Sun Hua Yang Ming Xia Zhang Ru Ban Ge Lin Xu Ya Ping Wu Le Xin Wang Yi Feng Du 《PloS one》2015,10(6)
Background and Objectives
Carotid artery stenting (CAS) is an important therapeutic strategy for patients with carotid artery stenosis. However, the potential influence of CAS on cognitive function in patients with carotid artery stenosis and cerebral lacunar infarction has not been determined. This study investigated changes in cognitive function associated with CAS and the factors related to these changes.Methods
This prospective cohort study comprised 579 Chinese patients with cerebral lacunar infarction and carotid artery stenosis for whom CAS was indicated, and a matched control group of 552 healthy individuals. Cognitive function before CAS and at scheduled intervals from 6 months to 3 years was assessed with instruments that included the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scale. Potential factors that might affect cognitive function were analyzed via logistic regression.Results
The MMSE and MoCA scores of the patients before CAS were significantly lower than that of the control subjects. These scores were significantly higher 6 months after CAS and sustained or increased throughout the 3-year follow-up. Also significantly improved after CAS from baseline were scores for an alternating trail test, cube copying, clock-drawing, attention, and delayed recall in an auditory-verbal learning test. Logistic regression analyses showed that age greater than 65 y, little education, diabetes, and hypertension were independent risk factors for deteriorated MoCA scores 3 years after CAS.Conclusion
CAS was associated with significantly improved cognitive function in cerebral lacunar infarction patients with severe stenosis. 相似文献100.
In our screening program for new agrochemicals from local wild plants, essential oil of Artemisia vestita Wall (Asteraceae) was found to possess strong insecticidal activity against maize weevil, Sitophilus zeamais Motsch. Essential oil of aerial parts of A. vestita was obtained from hydrodistillation and was investigated by GC and GC–MS. The main components of essential oil were grandisol (40.29%), 1,8-cineol (14.88%) and camphor (11.37%). The essential oil of A. vestita possessed strong fumigant toxicity against S. zeamais adults with a LC50 value of 13.42 mg/L air. The essential oil of A. vestita also showed contact toxicity against S. zeamais adults with a LD50 value of 50.62 mg/adult. 相似文献