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991.
目的:探讨应用时间-温度阈值控制肝脏LITT的可行性.方法:16只实验兔,分成2组,均在介入性MRI引导下行LITT.组1和组2分别加热到60℃和时间-温度阈值.测量光导纤维尖端至测温针尖的距离(D1),以及光导纤维尖端至凝固性坏死最外缘的距离(D2).结果:阈值温度54℃最为多见.组1D1与D2的差异有显著性统计学意义.组1达到时间-温度阈值平均节约时间(或能量)26.63%.结论:时间-温度阈值控制肝脏LITT能完全消融肝组织,节约消融时间和能量,减少正常组织损伤.  相似文献   
992.
BACKGROUND: Language barriers among some Latinos may contribute to the lower rates of colorectal cancer (CRC) screening between Latinos and non-Latino Whites. The purpose of this study was to examine the relationship between language and receipt of CRC screening tests among Latinos and non-Latinos using a geographically diverse, population-based sample of adults. METHODS: Cross-sectional analysis of the Behavioral Risk Factor Surveillance System (BRFSS) survey. Analysis included adults age 50 years and older, who completed the 2006 BRFSS in a state that recorded data from English- and Spanish-speaking participants. RESULTS: The primary outcome measure was receipt of colorectal screening tests (fecal occult blood testing within prior 12 months and/or lower endoscopy within 10 years). Of the 99,895 respondents included in the study populations, 33% of Latinos responding-in-Spanish reported having had CRC testing, whereas 51% of Latinos responding-in-English and 62% of English-speaking non-Latinos reported test receipt. In multivariable analysis, compared with non-Latinos, Latinos responding-in-English were 16% less likely to have received CRC testing [odds ratio (OR), 0.84; 95% confidence interval (95% CI), 0.73-0.98], and Latinos responding-in-Spanish were 43% less likely to have received CRC testing (OR, 0.57; 95% CI, 0.44-0.74). Additionally, compared with Latinos responding-in-English, Latinos responding-in-Spanish were 36% less likely to have received CRC testing (OR, 0.64; 95% CI, 0.48-0.84). CONCLUSION: Latinos responding to the 2006 BRFSS survey in Spanish had a significantly lower likelihood of receiving CRC screening tests compared with non-Latinos and to Latinos responding-in-English. Based on this analysis, Spanish language use is negatively associated with CRC screening and may contribute to disparities in CRC screening.  相似文献   
993.
目的:探讨团注(Bolus)技术在多层螺旋CT血管成像(multi—slice spiral CT angiography,MSCTA)最佳延迟时间设定中的作用和意义。材料和方法:随机选取患者326例分三组进行比较,第一组87例采取经验值设定延迟时间;第二组109例运用智能跟踪技术启动扫描;第三组130例采取Test Bolus技术,根据测得目标血管的时间一密度曲线设定延迟时间。结果:第一组图像质量优22例、良38例、差27例;第二组图像质量优62例、良44例、差3例;第三组图像质量优120例、良8例、差2例;Test Bolus技术组图像质量明显优于经验值组,有显著差异(P〈0.05);而与智能组,腹主A组无显著差异(P〉0.05),优于其余各组(P〈0.05)。结论:用Test团注测试扫描技术设定延迟时间能得到优质的CTA原始图像,有利于多层螺旋CT取得更好的三维血管重建图像。  相似文献   
994.
This study evaluated endometrial histology in women using the once-a-month injectable contraceptive Cyclofem for one year or more. The study received IRB approval. Seventeen Cyclofem users accepted to be submitted to an endometrial biopsy. All the samples were collected with an endometrial suction curette (Z-Sampler, ZSI Gynecological Product, Chasworth, CA, USA) in an outpatient clinic, 27–33 days after the last injection. The material was fixed immediately in Bouin solution prior to wax embedding and screened as a routine histological examination by a senior pathologist. The pathologist did not know the bleeding status of each woman or the number of injections each woman had received before the biopsy. All women recorded bleeding and spotting for the last 60 days prior to the biopsy. The mean age of volunteers was 25.9 years (range 21–32) and the mean number of injections received was 24.8 (range 14–47). The results were: 4 out of 17 biopsies were found to be inadequate for diagnosis because they consisted of only blood and mucus. Two of these women were bleeding regularly and the other 2 had amenorrhea. Eight endometrial samples presented a proliferative pattern and, in this group, 3 women had amenorrhea and 5 were bleeding regularly. The other 5 biopsies were reported as secretory endometrium, and 4 of them showed pseudodecidual reaction compatible with the administration of progestin. All of these women were bleeding regularly. The results of the biopsies were not related to the number of injections received nor to the age of the women. In conclusion, long-term administration of the injectable contraceptive Cyclofem did not produce adverse alterations in the endometrium as hyperplasia.  相似文献   
995.
Congenital gallbladder duplication, an uncommon but potentially complicating malformation, is rarely diagnosed preoperatively. A case in which the diagnosis was achieved by real-time ultrasonography is presented and correlated with hepatobiliary scintigraphy. The efficacy of these diagnostic modalities is discussed, and the available literature is reviewed.  相似文献   
996.
Cytomics aims to determine the molecular phenotype of single cells. Within the context of the -omics, cytomics allows the investigation of multiple biochemical features of the heterogeneous cellular systems known as the cytomes. Cytomics can be considered as the science of single cell-based analyses that links genomics and proteomics with the dynamics of cell and tissue function, as modulated by external influences. Inherent to cytomics are the use of sensitive, scarcely invasive, fluorescence-based multiparametric methods and the event-integrating concept of individual cells to understand the complexity and behaviour of tissues and organisms. Among cytomic technologies, flow cytometry, confocal laser scanning microscopy and laser capture microdissection are of great relevance. Other recent technologies based on single cell bioimaging and bioinformatic tools become important in drug discovery and toxicity testing, because of both high-content and high-troughput. The multiparametric capacity of cytomics is very useful for the identification, characterization and isolation of stem cell populations. In our experience, flow cytometry is a powerful and versatile tool that allows quantitative analysis of single molecules, prokaryotic and eukaryotic cells for basic, biotechnological, environmental and clinical studies. The dynamic nature of cytomic assays leads to a real-time kinetic approach based on sequential examination of different single cells from a population undergoing a dynamic process, the in fluxo level. Finally, cytomic technologies may provide in vitro methods alternative to laboratory animals for toxicity assessment.  相似文献   
997.
BACKGROUND AND PURPOSE. Peer norms influence the adoption of behavior changes to reduce risk for HIV (human immunodeficiency virus) infection. By experimentally intervening at a community level to modify risk behavior norms, it may be possible to promote generalized reductions in HIV risk practices within a population. METHODS. We trained persons reliably identified as popular opinion leaders among gay men in a small city to serve as behavior change endorsers to their peers. The opinion leaders acquired social skills for making these endorsements and complied in talking frequently with friends and acquaintances. Before and after intervention, we conducted surveys of men patronizing gay clubs in the intervention city and in two matched comparison cities. RESULTS. In the intervention city, the proportion of men who engaged in any unprotected anal intercourse in a two-month period decreased from 36.9 percent to 27.5 percent (-25 percent from baseline), with a reduction from 27.1 percent to 19.0 percent (-30 percent from baseline) for unprotected receptive anal intercourse. Relative to baseline levels, there was a 16 percent increase in condom use during anal intercourse and an 18 percent decrease in the proportion of men with more than one sexual partner. Little or no change was observed among men in the comparison cities over the same period of time. CONCLUSIONS. Interventions that employ peer leaders to endorse change may produce or accelerate population behavior changes to lessen risk for HIV infection.  相似文献   
998.
The contribution of diet and surgery to the brain weight deficits observed in artificially reared rats was investigated. Four day old Long Evans rat pups were assigned to an artificially reared (AR) or mother reared (MR) group. AR pups were encannulated and fed either rat milk (AR-MOM) or replacement formula (AR-MES). MR pups received a sham encannulation (MR-SHAM) or no surgery (MR-CONT) before being returned to their dam for rearing. On day 7 all the animals were killed. Brain weights and visceral organ weights were obtained. There was no significant difference between the MR groups on any measure except stomach weights. AR-MOM pups had larger visceral organ weights than pups in the other groups. AR-MOM and AR-MES pups had similar whole brain weights, smaller than those of the MR pups. However, the cerebellar weights, and to a lesser extent, brainstem weights, showed improvements in the AR-MOM group, over the AR-MES group. Neither the effect of surgery nor of diet alone can account for the organ weight differences that have been described in AR rats. The possibility that normal growth may be primarily dependent on diet at one stage of development, with other factors gaining importance at later stages is discussed.  相似文献   
999.
目的:揭示环氧合酶2(COX-2)在肾癌细胞中的表达情况,通过COX-2抑制剂NS398作用肾癌细胞探讨非甾体抗炎药(NSAID)对肾癌细胞增殖作用的影响及其可能的作用机制。方法:采用标准的细胞培养方法对人肾癌786-0细胞进行培养,将NS398分别以25,50,100,150及200μmol/L的剂量加入细胞中作用24及48h后,MTT法检测NS398对肾癌细胞增殖的影响;作用24h后,流式细胞仪测定细胞凋亡的情况,EIA法测定细胞中前列腺素E(2PGE2)含量的变化,Western blotting测定COX-2蛋白表达的情况。结果:NS398对肾癌786-0细胞具有较强的抑制作用,且这种抑制作用随浓度和时间的增加而增大,呈浓度依赖关系(P<0.05);NS398作用肾癌786-0细胞24h后,在细胞周期G0/G1期前出现明显的亚二倍体凋亡峰,随着浓度升高,凋亡峰亦越来越增高(P<0.05);NS398可抑制PGE2释放,并且这种抑制作用呈剂量效应,与对照组相比有统计学意义(P<0.05);不同浓度NS398作用下的肾癌786-0细胞中,COX-2的表达明显减弱,且呈剂量梯度下降。结论:NS398通过诱导凋亡来抑制肾癌786-0细胞的增殖;NS398诱导肾癌786-0细胞的凋亡作用机制可能是通过抑制COX-2的表达,降低肾癌786-0细胞PGE2的合成,减少前列腺素对肿瘤细胞增殖的刺激作用来抑制增殖和促进凋亡的。  相似文献   
1000.
Heterotopic brain in the nasopharynx   总被引:2,自引:0,他引:2  
  相似文献   
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