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991.
桡神经及其深支的血供 总被引:1,自引:0,他引:1
在25具成人尸体(50例)上,观测了桡神经及其深支的血供。桡神经的营养动脉平均为4.36±0.26支,营养动脉和来源动脉的外径平均为0.38±0.08mm和1.65±0.05mm。桡神经深支的营养动脉平均为1.72±0.16支,营养动脉和来源动脉的外径平均为0.29±0.01mm和1.91±0.07mm。 相似文献
992.
National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training. 相似文献
993.
994.
目的 赤芝 (Ganoderma lucidum) 在民间被用于糖尿病治疗,但缺乏数据支撑,需探索其化学成分及其是否具有抗糖尿病作用以利于临床推广。方法 采用多种分离技术,如 MCI gel CHP 20P、RP-18、Sephadex LH-20、硅胶柱色谱、 制备薄层色谱 (Preparative Thin-Layer Chromatography,PTLC) 和高效液相色谱 (High Performance Liquid Chromatography, HPLC) 等,对云南产赤芝的低极性成分进行研究,利用一维 (One Dimensional,1D) 和二维 (Two Dimensional,2D) 核磁共振波谱 (Nuclear Magnetic Resonance Spectroscopy,NMR) 等方法鉴定化合物结构,在C2C12细胞胰岛素抵抗体外模型中研究其活性。结果 从云南2个产地赤芝中分离鉴定8个杂萜-三萜杂聚体类新化合物,ganolucinins D-K (1-8),其中化合物7和8可上调胰岛素受体底物1 (Insulin Receptor Substrate 1,IRS1) 和蛋白激酶B (Protein Kinase B,PKB/Akt) 磷酸化, 8可促进C2C12细胞葡萄糖摄取。结论 赤芝中可能存在一系列杂萜-三萜杂聚体类化合物,其中化合物8具有改善胰岛素抵抗潜力,可能是灵芝抗糖尿病的药效物质之一。 相似文献
995.
Galactosylated PVDF membrane promotes hepatocyte attachment and functional maintenance 总被引:2,自引:0,他引:2
Lu HF Lim WS Wang J Tang ZQ Zhang PC Leong KW Chia SM Yu H Mao HQ 《Biomaterials》2003,24(27):4893-4903
One of the major challenges in BLAD design is to develop functional substrates suitable for hepatocyte attachment and functional maintenance. In the present study, we designed a poly(vinylidene difluoride) (PVDF) surface coated with galactose-tethered Pluronic polymer. The galactose-derived Pluronic F68 (F68-Gal) was adsorbed on PVDF membrane through hydrophobic-hydrophobic interaction between PVDF and the polypropylene oxide segment in Pluronic. The galactose density on the modified PVDF surface increased with the concentration of the F68-Gal solution, reaching 15.4 nmol galactosyl groups per cm2 when a 1 mg/ml of F68-Gal solution was used. The adsorbed F68-Gal remained relatively stable in culture medium. Rat hepatocytes attachment efficiency on F68-Gal modified PVDF membrane was similar to that on collagen-coated surface. The attached hepatocytes on PVDF/F68-Gal membrane self-assembled into multi-cellular spheroids after 1 day of culture. These attached hepatocytes in spheroids exhibited higher cell functions such as albumin synthesis and P450 1A1 detoxification function compared to unmodified PVDF membrane and collagen-coated surface. These results suggest the potential of this galactose-immobilized PVDF membrane as a suitable substrate for hepatocyte culture. 相似文献
996.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
997.
Han Lü Sixun Zheng Bing Zhang Xiaozhen Tang 《Macromolecular chemistry and physics.》2004,205(6):834-842
Summary: The blends of poly(hydroxyether sulfone) (PHES) with poly(N‐vinylpyrrolidone) (PVPy) were investigated by means of differential scanning calorimetry (DSC) and FTIR spectroscopy. The miscibility of the blend system was established on the basis of the thermal analysis results. DSC showed that the PHES/PVPy blends prepared by casting from N,N‐dimethylformamide (DMF) possessed single, composition‐dependent glass transition temperatures, indicating that the blends are miscible in the entire composition. The experimental glass transition temperatures have higher values than those calculated on the basis of additive behavior; the variation of the glass transition temperatures of the blends was accounted for by the Kwei equation. FTIR studies indicate that competitive hydrogen bonding interactions exist upon addition of PVPy to the system, which were involved in the self‐ and cross‐association, i.e., ? OH···O?S, ? OH···OH of PHES and ? OH···O?C< of PVPy. The FTIR spectra in the range of the sulfonyl stretching vibrations showed that the hydroxyl‐associated sulfonyl groups are partially “set free” upon addition of PVPy to the system. The IR spectroscopic investigation of both the model compounds and the PHES/PVPy blends suggests that the strength of the hydrogen bonding interactions in the blend system increases in the following order: ? OH···O?S, ? OH···OH and ? OH···O?C<.
998.
Xiao Y Zhang Wing Y Chan Bruce M Whitney Dai M Fan John H S Chow Yong Liu Enders K W Ng Sheung C S Chung 《Diagnostic molecular pathology》2002,11(3):135-139
Helicobacter pylori (HP) infection induces expression of IL-8 and IL-10 in benign gastric epithelium. This study compared the expression of cytokines in CD4+ and CD8+ lymphocyte subsets of peripheral blood lymphocytes (PBL), benign mucosal lymphocytes (ML), and tumor infiltrative lymphocytes (TIL) as well as in the benign and malignant epithelial cells of the same patient, with respect to the presence of HP infection, lymph node metastases, and tumor histologic type. The mRNA of the cytokines was measured by a semiquantitative RT-PCR method. The levels were ranked and compared using the Wilcoxon sign-ranked test. Compared with CD8+ ML, the CD8+ TIL expresses higher levels of IL-6 and IL-8 but lower level of IL-4 in patients with lymph node metastases. In patients with HP infection, expression of IL-8 and IL-10 was higher in the gastric carcinoma cells than in the benign epithelial cells while expression of IL-6 and IL-8 were higher in CD8+ TIL than CD8+ ML. Overexpression of IL-8 in HP associated gastric carcinomas suggested that they might have arisen from HP-infected epithelial cells. 相似文献
999.
Mengshu Zhang Likui Lu Bin Wei Yingying Zhang Xiang Li Yajun Shi Wei Ge Miao Sun 《American journal of medical genetics. Part A》2020,182(10):2432-2436
Brachydactyly type A (BDA) is defined as short middle phalanges of the affected digits and is subdivided into four types (BDA1‐4). To date, the molecular cause is unknown. However, there is some evidence that pathogenic variants of HOXD13 could be associated with BDA3 and BDA4. Here, we report a Chinese autosomal dominant BDA3 pedigree with a novel HOXD13 mutation. The affected individuals presented with an obviously shorter fifth middle phalanx. The radial side of the middle phalanx was shorter than the ulnar side, and the terminal phalanx of the fifth finger inclined radially and formed classical clinodactyly. Interestingly, the index finger was normal. The initial diagnosis was BDA3. However, the distal third and fourth middle phalanges were also slightly affected, resulting in mild radial clinodactyly. Both feet showed shortening of the middle phalanges, which were fused to the distal phalanges of the second to the fifth toes, as reported in BDA4. Therefore, this pedigree had combined BDA3 and atypical BDA4. By direct sequencing, a 13 bp deletion within exon 1 of HOXD13 (NM_000523.4: c.708_720del13; NP_000514.2: p.Gly237fs) was identified. The 13 bp deletion resulted in a frameshift and premature termination of HOXD13. This study provides further evidences that variants in HOXD13 cause BDA3‐BDA4 phenotypes. 相似文献
1000.
Zhang C Cohen JM Cangiarella JF Waisman J McKenna BJ Chhieng DC 《American journal of clinical pathology》2000,113(1):21-28
Metastases or secondary deposits account for 16% of the malignant neoplasms involving the major salivary glands. A correct diagnosis of a secondary neoplasm is important to avoid unnecessary radical surgery and to guide further therapy. Fine-needle aspiration biopsy (FNAB) is an excellent noninvasive diagnostic tool for evaluating salivary gland lesions. We reviewed 36 secondary malignant salivary gland neoplasms evaluated by FNAB. Ancillary studies were performed in selected cases. Follow-up included clinical correlation and review of histologic material. For 4 adenocarcinomas, 4 squamous cell carcinomas, 1 undifferentiated carcinoma, 1 cutaneous basal cell carcinoma, 10 cutaneous melanomas including 1 desmoplastic variant, 3 osteosarcomas, 11 non-Hodgkin lymphomas, and 2 multiple myelomas, there was 1 false-negative FNAB result. The desmoplastic melanoma was interpreted as reactive lymphoid hyperplasia. A malignant diagnosis was given in all remaining cases except the secondary basal cell carcinoma, which was diagnosed as a neoplasm with basal cell features. FNAB is a reliable tool to differentiate hematologic malignant neoplasms and melanomas from other salivary gland neoplasms. A complete knowledge of the clinical history, review of previous pathologic materials, and, in some instances, the use of ancillary studies are crucial for recognizing solid malignant neoplasms secondarily involving the salivary glands. 相似文献