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41.
Anne Hansen Ree Kristin Bjørnland Nils Brünner Harald Thidemann Johansen Kjetil Boye Pedersen Ansgar O. Aasen Øystein Fodstad 《Clinical & experimental metastasis》1998,16(3):205-215
Hormone-independent growth and invasiveness represent phenotypic properties acquired during early progression of breast cancer. We compared human mammary adenocarcinoma cells, MCF-7, which are estrogen-dependent and poorly metastatic, with the estrogen-independent and highly metastatic subline, MCF7/LCC1, with regard to expression of tissue-degrading factors of the matrix metalloproteinase (MMP)-and urokinase (uPA)-dependent degradative pathways, as well as for their in vitro invasive properties. Both cell lines showed low constitutive mRNA expression of the MMP inhibitor TIMP-1. Baseline expression of TIMP-2 mRNA was also very low in MCF-7 cells, whereas the MCF7/LCC1 level was much higher (~10- fold). Furthermore, both cell lines revealed low constitutive capacity to migrate in an in vitro invasion assay. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 nM) induced the mRNAs for TIMP-1 as well as for MMP-1, MMP-9, the uPA receptor, and the uPA inhibitor PAI-1, am ongst which only the responses of MMP-9 and PAI-1 were cell-specific. The mRNA levels of MMP-9 and PAI-1 were ~10-fold and ~15-fold higher in MCF7/LCC1 cells compared to MCF-7 cells. The secretion of immuno-reactive PAI-1 was considerably elevated (. 20-fold) in TPA-treated MCF7/LCC1 cells, whereas the TPA-dependent level of 92-kDa MMP-9 was only ~2-fold higher in MCF7/LCC1 cells than in MCF-7 cells. In both cell lines treatment with TPA was associated with an increase (~10-fold) in in vitro migration, which in the MCF7/LCC1 cells was significantly attenuated by a reconstituted basement membrane extract (Matrigel). These data suggest that TPA-responsive in vitro invasive properties that are probably associ-ated with PAI-1 expression may co-vary with progression from hormone-dependent to -independent breast cancer. © Rapid Science 1998 相似文献
42.
A new pseudo-peptide of Arg-Gly-Asp (RGD) with inhibitory effect on tumor metastasis and enzymatic degradation of extracellular matrix 总被引:2,自引:0,他引:2
Hideki Fujii Naoyuki Nishikawa Hiroyuki Komazawa Makoto Suzuki Masayoshi Kojima Isamu Itoh Aya Obata Koichi Ayukawa Ichiro Azuma Ikuo Saiki 《Clinical & experimental metastasis》1998,16(1):94-104
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998 相似文献
43.
Conversion of highly malignant colon cancer from an aggressive to a controlled disease by oral administration of a metalloproteinase inhibitor 总被引:3,自引:0,他引:3
Zili An Xiaoen Wang Neville Willmott Surinder K. Chander Simon Tickle Andrew J. P. Docherty Andrew Mountain Andrew T. Millican Richard Morphy John R. Porter R. Ola Epemolu Tetsuro Kubota A. R. Moossa Robert M. Hoffman 《Clinical & experimental metastasis》1997,15(2):184-195
In this study, we describe the activity of CT1746, an orally-active synthetic MMP inhibitor that has a greater specificity for gelatinase A, gelatinase B and stromelysin than for interstitial collagenase and matrilysin, in a nude mouse model that better mimics the clinical development of human colon cancer. The model is constructed by surgical orthotopic implantation (SOI) of histologically-intact tissue of the metastatic human colon tumor cell line Co-3. Animals were gavaged with CT1746 twice a day at 100 mg/kg for 5 days after the SOI of Co-3 for 43 days. In this model CT1746 significantly prolonged the median survival time of the tumor-bearing animals from 51 to 78 days. Significant efficacy of CT1746 was observed on primary tumor growth (32% reduction in mean tumor area at day 36), total spread and metastasis (6/20 treated animals had no detectable spread and metastasis at autopsy compared to 100% incidence of secondaries in control groups). Efficacy of CT1746 could also be seen on reducing tumor spread and metastasis to individual organ sites such as the abdominal wall, cecum and lymph nodes compared to vehicle and untreated controls. We conclude that chronic administration of a peptidomimetic MMP inhibitor via the oral route is feasible and results in inhibition of solid tumor growth, spread and metastasis with increase in survival in this model of human cancer, thus converting aggressive cancer to a more controlled indolent disease. 相似文献
44.
53例涎腺腺样囊性癌MMP—2和MMP—9表达与神经浸润和淋巴结转移的关系 总被引:4,自引:0,他引:4
目的研究涎腺腺样囊性癌MMP-2和MMP-9表达情况,评估其与涎腺腺样囊性癌神经浸润和淋巴
结转移的关系。方法选取53例涎腺腺样囊性癌,以抗MMP-2和MMP-9单克隆抗体用Envision法进行免疫
组织化学染色和半定量分析。结果MMP-2和MMP-9在涎腺腺样囊性癌中的表达率分别为67.92%和
79.25%;有神经浸润的腺样囊性癌其MMP-2和MMP-9的表达水平远高于无浸润者(P<0.05,P<0.05);随
着MMP-2和MMP-9的表达水平增高,淋巴结转移率也增高(P<0.05,P<0.05)。结论提示MMP-2和
MMP-9的高表达与涎腺腺样囊性癌易侵犯神经的特性及发生淋巴结转移密切相关。 相似文献
45.
正、反义组织金属蛋白酶抑制剂1基因转染对肾小球系膜细胞凋亡及相关基因表达的影响 总被引:5,自引:0,他引:5
目的 探讨正、反义组织金属蛋白酶抑制剂1(TIMP-1)对肾小球系膜细胞凋亡的影响。方法 利用前期工作中克隆出的人TIMP-1全长cDNA,分别构建出表达正义及反义TIMP-1的重组真核表达载体pcDNA3-TIMP-1(PTs),pcDNA3-ATIMP-1(PTas),并将上述重组质粒转染至大鼠的肾小球系膜细胞中,Northern杂交检测正、反义TIMP-1的表达。无血清诱导大鼠系膜细胞凋亡,利用DNA缺口末端标记(TUNEL)分析、DNA电泳技术在无血清后的不同时间点检测细胞凋亡,RT-PCR的方法检测凋亡相关基因的表达。结果 转染PTas的大鼠系膜细胞可以高效表达反义TIMP-1,无于血清诱导12h开始发生凋亡;无外源基因转染及空载体转染的大鼠系膜细胞在无血清48h发生凋亡;而转染正义TIMP-1的大鼠系膜细胞可高效表达正义TIMP-1,在无血清4d时才发生凋亡。TIMP-1的高表达或低表达可引起大鼠系膜细胞bax的下调或上调,但并不影响bcl-2的表达。结论 TIMP-1可以抑制无血清诱导的大鼠系膜细胞的凋亡,反义TIMP-1对之则有促进作用。这提示TIMP-1在肾脏除了抑制细胞外基质的作用外还具有新的功能。 相似文献
46.
肝癌组织中TIMP-1和TIMP-2的表达意义 总被引:7,自引:1,他引:6
目的 了解TIMP-1和TIMP-2在肝癌组织中的表达状态,探讨TIMP-1和TIMP-2在肝癌组织生长、侵润及转移中所起的作用。方法 以抗TIMP-1和TIMP-2单克隆抗体(mAb)为试剂,采用免疫组织化学法检测原发性肝癌、肝高分化腺癌的肝组织中TIMP-1和TIMP-2的表达,并与10例正常肝组织做对照。结果 10例原发性肝癌患的肝组织中TIMP-1和TIMP-2蛋白表达的阳性率为100%,在癌组织及非癌组织中均有表达。癌组织中的TIMP-1和TIMP-2蛋白表达的强度比较为6例高于、4例低于周围的非癌组织(慢性肝炎及肝硬化组织),癌组织中TIMP-1和TIMP-2蛋白的表达呈散在性分布,但TIMP-1比TIMP-2表达强。9例肝高分化腺癌的腺癌组织中无TIMP-1和TIMP-2相关抗原的表达,但癌周组织的肝细胞有3例TIMP-1和TIMP-2蛋白表达为阳性。10例正常肝组织中TIMP-1和TIMP-2蛋白表达均为阴性。结论 TIMP-1和TIMP-2存在于原发性肝癌的癌组织中,其表达的部位与强度可能与癌的生长、浸润及转移有关。 相似文献
47.
基质金属蛋白酶-2与喉癌的相关性研究 总被引:3,自引:0,他引:3
目的检测喉鳞癌组织中基质金属蛋白酶-2(MMP-2)的表达情况,探讨其表达与喉癌临床病理关系。方法应用免疫组化法,检测43例喉鳞癌组织中MMP-2的表达。结果43例喉鳞癌组织中,29例(67.4%)MMP-2表达阳性,其中颈淋巴结转移组明显高于无淋巴结转移组(P〈0.05),深部浸润的癌巢及基底膜附近的肿瘤细胞染色尤为明显。结论MMP-2能破坏基底膜,与喉癌浸润转移密切相关。 相似文献
48.
O-charoenrat P Rhys-Evans P Court WJ Box GM Eccles SA 《Clinical & experimental metastasis》1999,17(7):631-639
Evidence suggests that there is an association between the abnormal expression of members of the c-erbB receptor tyrosine kinase family and poor prognosis in head and neck squamous cell carcinomas (HNSCC). Until now, the relative
contributions of different c-erbB ligands to HNSCC progression have not been clearly defined. In this paper we examined the effects of ligands with different
c-erbB receptor specificities in terms of their stimulation of HNSCC proliferation, expression of matrix metalloproteinases (MMPs)
and invasion. Heregulin-beta1 (HRG-β1; selective c-erbB3/B4 ligand) was found to stimulate proliferation in the majority of cell lines, whereas epidermal growth factor (EGF; EGFR
ligand) and betacellulin (BTC; EGFR/B4 ligand) induced variable responses. All three ligands up-regulated multiple MMPs including
collagenases, stromelysins, matrilysin and gelatinase B (MMP-9) but had minimal or no effects on gelatinase A (MMP-2), MT1-MMP
and tissue inhibitors of MMPs (TIMPs). MMP-9 mRNA was induced to a higher level than other MMPs, although with slower kinetics.
HRG-β1 was less active than EGF and BTC at the optimal concentration (relative potency of EGF:BTC:HRG = 3:4:1). In vitro invasion through Matrigel was also increased by all three ligands in proportion to their MMP up-regulation. A specific anti-EGFR
monoclonal antibody (mAb ICR62) inhibited MMP up-regulation, migration and invasion induced by all three ligands, whereas
an anti-c-erbB-2 mAb ICR12 inhibited mitogenic and motogenic responses following ligand stimulation but had no effect on MMP expression.
These results suggest that c-erbB ligands may differentially potentiate the invasive phenotype of HNSCC via co-operative induction of cell proliferation,
migration and proteolysis. The EGFR signalling pathway appears to be the dominant component controlling the proteolytic and
invasive phenotype in HNSCC, whereas the c-erbB-2 signalling pathway is responsible, in part, for the mitogenic and motogenic effects of ligands.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
49.
Thomas Kelly 《Clinical & experimental metastasis》1999,17(1):67-72
Seprase is a serine protease that is integral to the plasma membrane and is overexpressed by invasive tumor cells (Piñeiro-Sánchez et al., J Biol Chem 1997; 272: 7595–601; Monsky et al., Cancer Res 1994; 54: 5702–10). Seprase activity is most often assessed by zymography, which is not a quantitative assay. This study establishes a relatively simple and quantitative method for determining seprase activity. The degradation of a 3H-gelatin substrate is measured in the presence of 5 mM EDTA which inhibits matrix metalloproteinases but not seprase. The quantitative character of the assay was demonstrated using partially purified seprase from chicken embryos, a preparation that lacks detectable matrix metalloproteinase activity. In this assay, release of 3H-gelatin fragments is linear over time for 1.5 g/assay seprase concentration as well as for preparations concentrated or diluted by five fold (7.5 g/assay and 0.3 g/assay respectively). Additional experiments were performed to validate the quantification of seprase activity using the radiographic assay by comparing the results to zymography. Exposure to 22 or 37°C results in maximal seprase activity while exposure to 80 or 100°C completely abolishes seprase activity in both zymography and the radiographic assay. Exposure to 60°C abolished seprase activity as judged by zymography, but about 50% gelatinase activity was observed using the 3H-gelatin substrate. Immunopreciptiation with seprase-specific antibody specifically removed seprase and lowered the seprase activity remaining in the extracts as judged by both assays. Investigation of the seprase that was partially purified from human breast cancer tissue revealed that its specific activity (cpm gelatin fragments released/ {mg protein×h}) is five times greater than that of seprase purified from chicken embryos. This assay will be useful for determining the seprase activity in extracts of tumor tissues and cells as well as for identifying inhibitors of seprase. 相似文献
50.
Infiltrative capacity was found to distinguish separate T leukemia cell lines. Of seven T-cell lines four exhibited capacity
to infiltrate Matrigel. Analysis of infiltration was performed at the single-cell level throughout the Matrigel using a depth
meter. Further, we examined differences in migration capacity and metalloproteinase production between infiltrating and non-infiltrating
T-cell lines. The capacity to infiltrate was not directly correlated to the capacity to adhere to the Matrigel or to migrate
on/to extracellular matrix components. It is concluded that infiltration capacity does not simply reflect capacity to migrate
but represents a distinct functional property. The production of metalloproteinases and their inhibitors by the separate T-cell
lines was analyzed using rt PCR, biosynthetic labelling, zymography, immunoprecipitation and ELISA. All T-cell lines with
capacity to infiltrate produced matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) while
non-infiltrating cell lines did not express MMP-9. Expression of MMP-1, 2, 3, 10, 14 and 17 showed no correlation to capacity
to infiltrate. Analysis of infiltration in the presence of a metalloprotease inhibitor showed an increased number of cells
within the gel. This enhancement of infiltration suggests that the function of MMPs and/or their inhibitors in lymphocyte
infiltration is more complex than previously thought.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献