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81.
This study was conducted to estimate the risk of human cancer from the inhalation of formaldehyde in different indoor environments in Guiyang City in China. Offices had the highest mean formaldehyde concentration (0.11 mg/m(3)) and classrooms had the lowest mean formaldehyde concentration (0.04 mg/m(3)). The cancer risk levels in different indoor environments ranged from 6.96 x 10(-6 )to 2.48 x 10(-4) and were greater than the acceptable cancer risk 1 x 10(-6). High human formaldehyde risks imply a critical influence on human health in Guiyang City. The highest cancer risk values occurred in bedrooms (ranging from 1.87 in 10,000 to 2.48 in 10,000). For office workers, offices were the highest risk environment after bedrooms where formaldehyde concentration levels were identified. Students were the most sensitive population, and the highest priority should be given to protecting their health in indoor environments. Regulations and standards for low emission materials and public education in relation to indoor pollution are highly recommended in China to protect human health.  相似文献   
82.
Thymic epithelial tumors (TETs) are one of the rarest adult malignancies in the anterior mediastinum. Thymic carcinomas (TCs) are less prevalent among TETs, but they are more clinically aggressive. Immunotherapy has emerged as a promising therapeutic approach for refractory TETs, even though chemotherapy remains the conventional treatment for the advanced disease. However, limited attention has been paid to the features of the tumor microenvironment (TME) which might provide clinically relevant information and guide treatment regimen design. Especially, to date, there have been only a few studies focusing on the differences between the TME and genomic features preserved by TETs and TCs. We analyzed the TME and genomic characteristics of TETs using RNA sequencing and whole-exome sequencing, finding that distinct characteristics of TME in different pathogenic subtypes of TETs. According to those findings, we found that thymic carcinomas had significantly lower expression of HMGB1, a pro-inflammatory cytokine-related gene, than thymomas, and low HMGB1 expression was linked to a poor prognosis. Additionally, higher mutation burdens were significantly associated with the later stage and more advanced pathological types. Thymoma patients with lower mutation burdens tended to relapse within 3 years. In summary, different characteristics of TME and genomic features between thymoma and thymic carcinoma were associated with clinical outcomes of TETs and presented promisingly predictive value for efficacy and toxicity of immunotherapy.  相似文献   
83.
本文探讨了化妆品生产过程中细菌污染的主要原因,并对提高化妆品生产的卫生质量管理提出了针对性建议。  相似文献   
84.
Multi-stage heat treatment is an important method to improve the mechanical properties of Al-Si-Cu-Mg aluminum alloys. In this paper, the multi-stage heat treatment was carried out for the Cd-free and Cd-containing alloys. The experimental results show that the addition of Cd promoted the precipitation of Q″ and θ″, which led to the formation of a large number of fine, dispersed precipitates and a higher yield strength (YS) and ultimate tensile strength (UTS) for the Cd-containing alloys. The addition of Cd also altered the optimal heat treatment parameters. For the Cd-free alloys, the Cu-rich phase fully dissolved after three-stage heat treatment, and the YS and UTS of the three-stage heat-treated alloys were higher than their two-stage heat-treated counterparts. For the Cd-containing alloys, the three-stage heat treatment led to the precipitation of Cd-rich low melting point phases, caused defects, and reduced the mechanical properties of the alloy. The size and volume fractions of the precipitates were significantly less than those of the alloys after two-stage heat treatment and the strength of the alloys decreased. Therefore, the solution time should be strictly controlled for Cd-containing Al-Si-Cu-Mg alloys.  相似文献   
85.
Electrocatalytic conversion of carbon dioxide (CO2) into specific renewable fuels is an attractive way to mitigate the greenhouse effect and solve the energy crisis. AunCu100-n/C alloy nanoparticles (AunCu100−n/C NPs) with tunable compositions, a highly active crystal plane and a strained lattice were synthesized by the thermal solvent co-reduction method. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) results show that AunCu100−n/C catalysts display a subtle lattice strain and dominant (111) crystal plane, which can be adjusted by the alloy composition. Electrochemical results show that AunCu100−n/C alloy catalysts for CO2 reduction display high catalytic activity; in particular, the Faradaic efficiency of Au75Cu25/C is up to 92.6% for CO at −0.7 V (vs. the reversible hydrogen electrode), which is related to lattice shrinkage and the active facet. This research provides a new strategy with which to design strong and active nanoalloy catalysts with lattice mismatch and main active surfaces for CO2 reduction reaction.  相似文献   
86.
87.
Zhu Y  Zhou R  Yang R  Zhang Z  Bai Y  Chang F  Li L  Sokabe M  Goltzman D  Miao D  Chen L 《Hippocampus》2012,22(3):421-433
In this study, we employed 1α-hydroxylase knockout (1α-(OH)ase(-/-) ) mice to investigate the influence of 1,25-dihydroxy vitamin D(3) (1,25-(OH)(2) D(3) ) deficiency on the adult neurogenesis in the hippocampal dentate gyrus (DG). The numbers of both 24-hr-old BrdU(+) cells and proliferating cell nuclear antigen positive cells in 8-week-old 1α-(OH)ase(-/-) mice increased approximately twofold compared with wild-type littermates. In contrast, the numbers of 7- and 28-day-old BrdU(+) cells in 1α-(OH)ase(-/-) mice decreased by 50% compared with wild-type mice, while the proportion of BrdU(+) /NeuN(+) cells in BrdU(+) population showed no difference between 1α-(OH)ase(-/-) and wild-type mice. Apoptotic cells in the subgranular zone (SGZ) of DG markedly increased in 1α-(OH)ase(-/-) mice. Replenishment of 1,25-(OH)(2) D(3) , but not correction of serum calcium and phosphorus levels, completely prevented changes in the neurogenesis in 1α-(OH)ase(-/-) mice. The absence of 1,25-(OH)(2) D(3) led to an increase in the expression of L-type voltage-gated calcium channel (L-VGCC) and a decrease in the nerve growth factor (NGF) mRNA level. Treatment with the L-VGCC inhibitor nifedipine blocked the increased cell proliferations by 1,25-(OH)(2) D(3) deficiency. Administration of NGF significantly attenuated the loss of newborn neurons in 1α-(OH)ase(-/-) mice.  相似文献   
88.
脓疱型银屑病15例临床分析   总被引:4,自引:0,他引:4  
通过对15例脓疱型银屑病的临床资料分析,指出在发病诱因中、滥用皮质激素是导致由寻常型转为脓疮型的重要因素。防治方面,严重病例应早期使用皮质类固醇激素,并适时加用MTX(氨甲碟呤)。而对初发病例,病情不甚严重者、则以抗菌素加其他治疗,而不宜以皮质激素为首选药物。  相似文献   
89.
Little is known about esophageal high-grade intraepithelial neoplasia dominated by cytological atypia (HGINc). We aimed to elucidate the endoscopic features of HGINc compared with esophageal high-grade intraepithelial neoplasia dominated by architectural atypia (HGINa). All patients pathologically diagnosed as esophageal high-grade intraepithelial neoplasia after endoscopic submucosal dissection at our center between January 2018 and December 2019 were included in this study. According to the pathological diagnosis, the patients were divided into two groups: HGINa group and HGINc group. Basic characteristics and endoscopic information were collected in detail. Data were analyzed statistically. Binary logistic regression was performed and a predictive model for HGINc was established. Then we evaluated its predictive value and built a nomogram for clinical application. A total of 175 patients were included in this study (126 with HGINa and 49 with HGINc). Among 228 lesions found in all patients, there were 148 HGINa and 80 HGINc. The independent relevant factors for HGINc were tobacco and alcohol usage, color, and gross type. To predict risk of HGINc, a three-factor model (TFM) was established with a highest area under curve (AUC) as 0.869 (95% CI, 0.852, 0.939). When the cut-off value was set as 0.3569184, the diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for HGINc was 81.14%, 88.75%, 77.03%, 67.62%, and 92.68%, respectively. HGINc differs greatly in endoscopic features from HGINa in our study. It’s important to reduce misdiagnosis that our model was established with good predictive value for clinical application.  相似文献   
90.
Nanoliposomal irinotecan (nal-IRI) plus 5-fluorouracil and leucovorin (NalFL) comprises the current standard for gemcitabine-failed metastatic pancreatic ductal adenocarcinoma (PDAC). As liposomes generally accumulate in the spleen, we evaluated the impact of spleen volume on prognosis. We enrolled patients with metastatic PDAC who failed gemcitabine-based therapy and were initiated on NalFL between August 2018 and November 2020. The spleen volume before NalFL administration was evaluated. They were stratified into dose subgroups (i.e. low, < 48 mg/m2; intermediate, 48 - < 64 mg/m2; high, ≥ 64 mg/m2) by the average nal-IRI dose during the entire treatment, and multivariate analysis of overall survival (OS) was performed. We included 547 patients with a median age of 63 years (range, 27-89 years) and a median of 1 (range, 0-7) palliative chemotherapy regimen. The median spleen volume was 245 mL (range, 82-817 mL). Among patients with splenomegaly (≥ 245 mL), the low-dose subgroup had the worst median time to treatment failure (TTF, 1.8 months vs. 2.5 months vs. 2.5 months, P = 0.020) and OS (3.3 months vs. 5.9 months vs. 6.6 months, P = 0.018) as against no prognostic impact in patients without splenomegaly. In the multivariate analysis of patients with splenomegaly, performance status (PS) ≥ 2, body surface area (BSA) < 1.6 m2, prior fluoropyrimidine use, liver metastasis, and low-dose subgroup were independent poor prognostic factors. A low average nal-IRI dose was significantly associated with poor prognosis, especially among patients with splenomegaly. Further pharmacological studies should validate the relevance of spleen volume on the treatment outcomes of nal-IRI.  相似文献   
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