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排序方式: 共有480条查询结果,搜索用时 15 毫秒
1.
胶原酶诱导不同部位脑出血大鼠模型的神经功能比较 总被引:1,自引:1,他引:0
目的 观察胶原酶诱导纹状体和内囊部位脑出血模型的行为学和神经纤维损伤差异.方法 利用立体定向技术,将一定量的Ⅳ型胶原酶用微量进样器分别精确注入大鼠纹状体和内囊诱导脑出血模型,观察两组大鼠的运动功能差异,并进行大体形态学和神经纤维受损程度的比较.结果 内囊组大鼠的运动功能受损程度明显重于纹状体组大鼠,前者的神经纤维破坏程度显著重于后者.结论 不同部位的脑出血模型的神经损害程度存在差异,内囊区脑出血模型更适合于研究神经纤维的损伤机制及神经纤维的再生和修复. 相似文献
2.
3.
介绍一种大鼠肝细胞的分离和培养方法 总被引:2,自引:0,他引:2
介绍分离、纯化大鼠肝细胞(用胶元酶二步灌流和PercoⅡ不连续密度离心)及分离后的培养。此方法可靠易行,可制备出质量合格的肝细胞(实质细胞)。讨论了保证分离和纯化成功的一些关键步骤、条件和原理.提出分离肝细胞应首选胶元酶Ⅳ,PereoⅡ的渗透压和pH也是影响肝细胞的漂浮密度和存活能力的因素。 相似文献
4.
Kakinuma C Suda K Shibutani Y 《Virchows Archiv : an international journal of pathology》1999,434(1):83-89
We investigated the time-course of changes in pancreatic fibrosis accompanied with pancreatitis in WBN/Kob rats. The areas
of fibrosis and fatty replacement were analysed morphometrically, and biochemical measurements of pancreatic and plasma prolyl
hydroxylase and of pancreatic collagenase were assessed. Male rats showed acute pancreatitis at 2–3 months of age, lesions
that later underwent a transition to widespread fibrosis. The fibrosis then decreased, and the fibrotic tissue was replaced
with adipose tissue. Morphometrically, the fibrotic area reached its maximal size when the rats were 4 months old, diminishing
thereafter. The fibrosis occurred mainly in the intralobular space, and was principally attributable to type-III collagen.
Type-I collagen scarcely appeared throughout the experimental period. α-Smooth muscle actin appeared in and around myofibroblasts
that developed in an early stage and diminished later in accordance with the progressive manner of fibrosis. The plasma prolyl
hydroxylase level was higher in males than in females from 4 through 10 months of age. Pancreatic collagenase activity in
the males also increased during the same period. These findings suggest that pancreatic fibrosis in male WBN/Kob rats is affected
by the balance between prolyl hydroxylase and collagenase.
Received: 1 October 1998 / Accepted: 2 October 1998 相似文献
5.
Distribution of matrix metalloproteinases and their inhibitor, TIMP-1, in developing human osteophytic bone 总被引:3,自引:0,他引:3
SHARYN BORD ALAN HORNER ROSALIND M. HEMBRY JOHN J. REYNOLDS JULIET E. COMPSTON 《Journal of anatomy》1997,191(1):39-48
Connective tissues synthesise and secrete a family of matrix metalloproteinases (MMPs) which are capable of degrading most components of the extracellular matrix. Animal studies suggest that the MMPs play a role in bone turnover. Using specific polyclonal antisera, immunohistochemistry was used to determine the patterns of synthesis and distribution of collagenase (MMP-1), stromelysin (MMP-3), gelatinase A (MMP-2) and gelatinase B (MMP-9) and of the tissue inhibitor of metalloproteinases-1 (TIMP-1) within developing human osteophytic bone. The different MMPs and TIMP showed distinct patterns of localisation. Collagenase expression was seen at sites of vascular invasion, in osteoblasts synthesising new matrix and in some osteoclasts at sites of resorption. Chondrocytes demonstrated variable levels of collagenase and stromelysin expression throughout the proliferative and hypertrophic regions, stromelysin showing both cell-associated and strong matrix staining. Intense gelatinase B expression was observed at sites of bone resorption in osteoclasts and mononuclear cells. Gelatinase A was only weakly expressed in the fibrocartilage adjacent to areas of endochondral ossification. There was widespread but variable expression of TIMP-1 throughout the fibrous tissue, cartilage and bone. These results indicate that MMPs play a role in the development of human bone from cartilage and fibrous tissue and are likely to have multiple functions. 相似文献
6.
Matrix metalloproteinase expression in basal cell carcinoma: relationship between enzyme profile and collagen fragmentation pattern 总被引:2,自引:0,他引:2
Yucel T Mutnal A Fay K Fligiel SE Wang T Johnson T Baker SR Varani J 《Experimental and molecular pathology》2005,79(2):151-160
Matrix metalloproteinases (MMPs) with collagenolytic and gelatinolytic activities are up-regulated in basal cell carcinoma. In the present study we demonstrate that the major collagenolytic enzyme detected is MMP-1 (interstitial collagenase) while gelatinolytic enzymes include both MMP-2 (72-kDa gelatinase A) and MMP-9 (92-kDa gelatinase B). Significant fractions of all three enzymes are present as active forms. In spite of the fact that high levels of gelatinolytic enzymes are present, the major fragmentation products resulting from digestion of intact type I collagen are the 1/4 and 3/4 fragments (products of MMP-1-mediated digestion). Thus, it appears that the gelatinolytic enzymes are not capable of degrading the collagen fragments as rapidly as they are produced. Since previous studies have demonstrated that interaction of interstitial fibroblasts with high molecular weight fragments of type I collagen leads to increased MMP production, the present results suggest a mechanism underlying altered function of stromal elements in the connective tissue adjacent to the growing neoplasm. 相似文献
7.
目的:通过鞘内注射不同剂量的胶原酶,观察其对脊髓及周围组织的损伤作用。方法:把40只兔分成A、B、C、D、E5组,分别在鞘内注射0.3mL的生理盐水和24、50、100、250U的胶原酶,通过形态学、脊髓诱发电位和组织病理学的检查以观察胶原酶对上述组织的损伤。结果:鞘内注射胶原酶的4组兔中都有不同程度的瘫痪,没有瘫痪的兔其SCEP也有改变,病检发现脊髓、神经根和血管都有不同程度的损伤,胶原酶剂量越大,损伤越重。结论:胶原酶鞘内注射对兔脊髓及其周围组织有严重的损伤作用。 相似文献
8.
Separation of previously uncharacterised Echis ocellatus venom by phenyl-Superose FPLC (Fast Liquid Protein Chromatography) yielded eight protein fractions. Three of these displayed high proteolytic activity when assayed by in vivo and in vitro assays (including enzyme linked immunosorbant assay), and were further separated using Superdex 75 and Mono-Q FPLC. This resulted in the purification of a non-haemorrhagic 24 kDa metalloproteinase (EoVMP1, pI 7.0), and a haemorrhagic 56 kDa metalloproteinase (EoVMP2, pI 5.5). Following tryptic digest, short amino acid sequences of EoVMP1 and EoVMP2 were obtained using Edman degradation. Both sequences displayed homology when aligned with existing snake venom metalloproteinases (SVMPs). The strong homology observed among previously well-characterised SVMPs suggests that principles governing the interaction of substrates and inhibitors are likely to be similar for EoVMP1, EoVMP2 and all members of the reprolysin family. 相似文献
9.
F. Timár J. Botyánszki H. Süli-Vargha I. Babó J. Oláh G. Pogány A. Jeney 《Cancer chemotherapy and pharmacology》1998,41(4):292-298
Purpose: The objective of the present study was to examine the relevance of collagenase in the antitumor action of a melphalan peptide
(MHP) with a collagenase-cleavable sequence. The question was addressed as to whether collagenase may act as an activator
or a target in the antiproliferative mechanism of MHP. Methods: Melphalan was inserted into peptides representing the sequence Pro-Gln-Gly-Ile-Ala.Gly of the collagenase-cleavable site
in collagens. Changes in growth and collagenase IV activities of HT-1080, HT-29, HT-168, and MCF-7 cell cultures were investigated.
Results: The present investigations provide data indicating that Pro-Gln-Gly-Ile-Mel-Gly (melphalan hexapeptide, MHP) is a substrate
for both bacterial and 72-kDa type IV collagenases and that in this way it can generate Ile-Mel-Gly (melphalan tripeptide,
MTP) of higher cytotoxic potency. Indeed, the formation of MTP was detected in the conditioned medium of HT-1080, a collagenase
IV-producing human fibrosarcoma. In a comparison of equimolar concentrations of melphalan and its two peptide derivatives
(MHP and MTP), superior antiproliferative action of MTP was seen in HT-29, HT-1080, and HT-168 tumor cell cultures. However,
the relatively modest cytostatic actions of MHP were increased when bacterial collagenase was added to the cell cultures.
After melphalan treatment, reduced levels of both 92 and 72-kDa type IV collagenases were seen in the HT-1080 cell cultures.
However, the reduction of collagenase activity and the cell counts did not run parallel in the MTP- or MHP-treated cultures;
indeed, collagenase activity related to cell numbers showed an elevated level. Conclusions: As the conversion of MHP to the more toxic MTP was detected in the presence of collagenases, it is possible that collagenase-directed
activation of prodrugs may be a promising approach for the development of more selective cytostatic drugs against malignant
tumors with high collagenase activities.
Received: 6 October 1996 / Accepted: 22 July 1997 相似文献
10.