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1.
目的 探讨脂联素对高脂饮食诱导裸鼠胰岛素抵抗子宫内膜癌移植瘤生长的影响。方法 40只裸鼠随机分成高脂组和普食组,每组20只,分别喂养高脂饲料(high-fat diet,HFD)和普通饲料(normal diet,ND),10周后测定裸鼠空腹血糖(fasting blood glucose,FBG)和空腹血胰岛素(fasting serum insulin,FINS)水平,计算胰岛素抵抗指数(HOMA-IR),建立胰岛素抵抗裸鼠模型。第11周接种子宫内膜癌HEC-1B细胞,待瘤体长至0.5 cm时,两组随机选取10只裸鼠腹腔注射脂联素(adiponectin,APN)分为HFD+APN组、ND+APN组;其余裸鼠分别注射0.9%氯化钠分为HFD组、ND组;14周后,测定各组血糖和血脂的代谢情况。结果 高脂组裸鼠10周后的平均体重、体长、FBG、FINS、HOMA-IR均大于普食组,糖耐量试验和胰岛素耐量试验结果显示血糖水平亦高于普食组(均P<0.05);接种子宫内膜癌HEC-1B细胞后均成瘤,建模成功。HFD+APN组和ND+APN组移植瘤平均重量和体积增长速度均分别低于HFD组和ND组(均P<0.05)。HFD组和HFD+APN组14周后的FINS、HOMA-IR、TC和TG均较ND组和ND+APN明显升高(均P<0.01),且HFD组明显高于HFD+APN组(均P<0.01);HFD+APN组的血脂联素水平低于ND+APN组(P<0.01),HFD组则低于ND组(P<0.05)。结论 脂联素可改善高脂饮食导致的胰岛素抵抗,抑制子宫内膜癌移植瘤生长。  相似文献   
2.
目的 建立裸鼠鼻咽癌转移模型并探讨 E-选择素(ELAM-1)与鼻咽癌转移的相关性。方法 将鼻咽癌5-8F细胞悬液注射于裸鼠左后肢爪垫,观察裸鼠状态、成瘤情况并测量裸鼠体重及移植瘤长短径;采用连续病理切片苏木精-伊红染色观察移植瘤及转移情况,将16只人鼻咽癌荷瘤裸鼠分为转移组和非转移组;采用免疫组织化学法检测两组移植瘤组织中ELAM-1的表达。 结果 16只裸鼠均成瘤,成瘤率为100.0%,其中10只裸鼠出现转移瘤,转移率为62.5%。建模前,两组裸鼠体重差异无统计学意义[(13.83±0.56)g vs (14.62±0.30) g,t=1.026,P=0.071]。建模后4~7周,裸鼠瘤体体积呈指数增长,且转移组移植瘤增长速度较非转移组快,非转移组裸鼠瘤体体积小于转移组[(198.91 ± 163.29) mm3 vs (268.76 ±174.31) mm3t=4.376,P=0.005]。ELAM-1在鼻咽癌裸鼠移植瘤、淋巴结转移灶及远处转移灶中的表达均为阳性,主要表达于细胞膜。转移组移植瘤光密度值高于非转移组(0.4497±0.0705 vs 0.0435±0.0082,t=4.388,P=0.001)。结论 本研究成功构建稳定性好、移率高的鼻咽癌裸鼠移植瘤转移模型,且ELAM-1在裸鼠移植瘤中高表达,可促进鼻咽癌裸鼠移植瘤生长和转移。  相似文献   
3.
The association of MTHFR and CBS variants with the doubling time and responsiveness to several chemodrugs was analyzed in 26 human cancer xenografts. The tumors homozygous for the absence of insertion (NN) for the CBS 844ins68bp were more chemosensitive than those with insertion (NI) to TS-1 (P=0.0048), suggesting a potential effect of this variant on fluoropyrimidine efficacy. Furthermore, the doubling time of tumors with a variant C allele (AC or CC) in MTHFR-A1298C was significantly longer than that of tumors with a normal allele (AA) (P=0.0008). Twenty-nine cellular proliferation-related genes were associated with MTHFR-A1298C genotyping and with the doubling time.  相似文献   
4.
重度联合免疫缺陷小鼠的繁育及其应用初报   总被引:4,自引:1,他引:3  
应用带过滤罩的透明鼠在层流柜内繁育T和B淋巴细胞缺失的重度联合免疫缺陷(scid)小鼠获得成功,1993年5月至1994年4月,共繁育scid小鼠221只,寿命均超过12个月。平均每窝产仔数为5.5只,显著低于对照组BALB/c小鼠,不育率为14.9%,离乳率为88.2%,与BALB/c小鼠相比均无明显差异。scid小鼠4~10周龄的体重与同龄BALB/c小鼠相比无明显差异,微生物学检测均符合SP  相似文献   
5.
6.
Summary The ganglioside patterns of medulloblastomas have never been established; in this study we report the ganglioside profile of the human medulloblastoma cell line TE-671 grown as a xenograft in nude mice. Gangliosides were isolated and structurally analyzed by fast atom bombardment mass spectometry following permethylation. Identification of individual gangliosides was also performed by immunostaining of high-performance thin-layer chromatography-separated bands. Total ganglioside levels of 0.20 mol/g of tissue were obtained, consistent with those reported for human glioma cell lines grown as xenografts; predominant monosialogangliosides of TE-671 xenografts were II3--NeuAc-LacCer (GM3) and II3--NeuAc-GgOse3 Cer (GM2) but there were also relatively large proportions of IV3--NeuAc-LcOse4Cer (3-isoLM1), IV3--NeuAc-nLcOse4Cer (3-LM1) and a further ganglioside of the neolactoseries with an extra lactosamine moiety. The only oligosialoganglioside detected was IV3, II3--NeuAc2-GgOse4Cer (GD1a).Abbreviations: The gangliosides have been designated according to Svenerholm [18] GM3 II3--NeuAc-LacCer - GM2 II3--NeuAc-GgOse3Cer - GM1 II3--NeuAc-GgOse4Cer - 3-LM1 IV3--NeuAc-nLcOse4Cer - 3-isoLMI IV3--NeuAc-LcOse4Cer - Fuc-3-isoLMI IV3--NeuAc, III4-Fuc-LcOse4Cer - GD1a IV3, II3--NeuAc2-GgOse4Cer - FAB-MS Fast atom bombardment-mass spectometry - GC-MS gas chromatography-mass spectometry Supported by NC1 RO1 CA11898 to Dr. Bigner and B8803X-00627-24B from the Swedish Medical Research Council to Dr. L. Svennerholm  相似文献   
7.
Summary A suspension of cells from embryonic day 21 fetal pig ventral mesencephalon was transplanted into the striatum of 20 immunosuppressed rats with 6-hydroxydopamine-induced lesions of the nigrostriatal dopamine pathway. Of these rats, 15 showed reduction of amphetamine-induced ipsilateral rotation by 9 weeks and complete reversal of rotation by 14–17 weeks. Animals maintained stable reversal of rotations (contralateral direction) until cessation of Cyclosporin A (CyA) treatment at 15–20 weeks. Within 4–9 weeks after CyA removal, these rats showed exclusively ipsilateral rotations during behavioral testing which were comparable to pre-transplant levels, suggesting that the grafts were rejected upon cessation of CyA treatment. Rats were sacrificed and tyrosine hydroxylase (TH) immunohistochemistry was performed at several time points, both on and off CyA, to examine a possible correlation between the degree of rotational behavior and the number of TH- positive surviving grafted cells. Staining showed large numbers (230–12,329) of TH-positive surviving cells in animals displaying a high degree of rotational correction (1.6 to -9.6 net ipsilateral rotations/min) after cessation of CyA treatment. Two control groups, those transplanted with nonneuronal cells from the pig ventral mesencephalon (n=5) and those receiving only daily CyA injections (n=4) showed no significant reduction of net ipsilateral rotations throughout the experiment. No TH-positive surviving cells were seen in the one non-neuronal transplant analyzed. This data demonstrates long-term retention of xenografted tissue with immunosuppression and its concomitant restoration of normal motor behavior in the rat model of Parkinson's disease.  相似文献   
8.
Currently used bioprosthetic valves have several limitations such as calcification and functional deterioration, and revitalization through cellular ingrowth is impossible. To overcome these obstacles, we have developed a minimally immunogenic tissue-engineered valve that consists of an unfixed, decellularized porcine valve scaffold capable of being spontaneously revitalized in vivo after implantation. Porcine aortic root tissue was decellularized using detergents such as sodium lauryl sulfate and Triton X-100. The porcine valve was treated very gently and plenty of time was allowed for constituents to diffuse in and out of the matrix. In a preliminary study, a piece of decellularized porcine valve tissue was implanted into the rat subdermal space for 14 and 60 days and the structural integrity and calcification were evaluated. As an in vivo valve replacement model, the decellularized porcine valve was implanted in the pulmonary valve position in dogs and functional and histological evaluation was performed after 1, 2, and 6 months. Histological examination showed that the newly developed detergent treatment effectively removed cellular debris from the porcine aortic tissue. Decellularized porcine valve tissue implanted subdermally in rats showed minimal inflammatory cell infiltration and calcification. In the valve replacement model, spontaneous reendothelialization and repopulation of the medial cells were observed within 2 months, and good valve function without regurgitation was observed by echocardiography up to 6 months. The minimally immunogenic decellularized porcine valve proved effective in mitigating postimplant calcification and provided a suitable matrix for revitalizing prostheses through in situ recellularization, cellular ingrowth, and tissue remodeling.  相似文献   
9.
目的 探讨不同方法制作的无细胞异种真皮基质(Xeno-ADM)移植物降解吸收与炎症反应之间的关系。方法 猪和兔断层中厚皮片经Trypsin和TritonX-100等脱细胞,分别制成Xe-no-ADM和异体ADM(Allo-ADM),再按不同的预处理因素进行分组:(1)戊二醛交联的Xeno-ADM(A)组;(2)网状交联的Xeno-ADM(B)组;(3)未交联的:Xeno-ADM(C)组,预先被Xeno-ADM蛋白致敏的兔皮下植入;(4)交联的Xeno-ADM(D)组;(5)Allo-ADM(E)组。每组80块ADM分别埋植于兔耳和背部皮下。结果在背部的移植物较耳部炎性反应和降解吸收明显,至术后32wk时,E组以外的其它组移植物解剖学和组织学结构消失,D组和A组炎症反应滞后,可见较多的异物巨细胞,各组ADM炎症反应与降解/吸收的程度依次为:C>B>D>A>E(P相似文献   
10.
Organ-specific acellular matrix for reconstruction of the urinary tract   总被引:5,自引:0,他引:5  
In urology, replacement of organs or organ segments has proved problematic. Current techniques do not replicate complete organ function, and they cause well-known complications. With the acellular organ-specific matrix we have found a way to regenerate tissue components seen in the normal lower urinary tract. The time required for regeneration depends on the matrix size and function. The matrix is covered by urothelium migrating from the host, after which neovascularization occurs, followed by formation of smooth-muscle cells and nerves. In our studies, normal muscle lining and nerves providing functional tissue were demonstrable and no sign of antigenicity was evident, even after heterologous grafting. The regenerated rat bladder was evaluated by organ bath as well as by in vivo functional tests and demonstrated properties and functions similar to those of host tissue. Besides our obtaining encouraging results in the rat bladder, we also studied the organ-specific acellular matrix in other species (dog and rabbit) and other organ segments (ureter and urethra).  相似文献   
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