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1.
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
2.
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
3.
目的:比较显微内窥镜下椎间盘除术(MED)及MED与胶原酶溶核术(CCNL)联合应用治疗腰椎间盘突出症的临床疗效。方法:120例腰椎间盘突出症患者中,60例单纯行MED治疗(MED组),另60例在行MED的基础上向椎间盘内注射胶原酶600U(MED CCNL组)。术后观察并分析两组的疗效及并发症。结果:两组均顺利完成手术,未发生并发症。术后全部病例随访6~48个月,按照MacNab标准评定,MED组有效率为83.3%,MED CCNL组为95%,后者明显高于前者(P<0.05)。结论:MED与CCNL联合治疗腰椎间盘突出症较单纯MED治疗具有更好的疗效。 相似文献
4.
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
5.
目的分析臭氧髓核消溶术(A组)、后路开窗髓核摘除术(B组)以及胶原酶化学髓核消溶术(C组)治疗椎间盘突出症的方法和后期效果。方法采用统一的病例选择和疗效标准,对185例患者(其中A组60例,B组63例,C组62例)进行分析,比较3组治疗后评分和优良率。结果A组治疗后评分和优良率明显高于B组和C组,有非常显著性差异(P〈0.01),B组高于C组有显著性差异(P〈0.05)。结论椎间盘突出症不同治疗方法中,臭氧髓核消溶术和胶原酶化学髓核消溶术明显优于开窗髓核摘除术,具有基本无创的优点。而开窗髓核摘除术相对而言创伤较大,对脊柱的稳定性有一定的影响。臭氧髓核消溶术是椎间盘突出症治疗方法中最理想的方法。 相似文献
6.
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
7.
目的观察DSA引导下臭氧与胶原酶联合治疗腰椎间盘突出症的临床应用价值。方法56例腰椎间盘突出症患者在DSA监视引导下,经患侧后方穿刺成功后,病变椎间盘注射60μg/mL O3 20~30mL,盘外及神经根周围注入浓度为30μg/mL O3 10-20mL,后经骶管裂孔穿刺置管于硬膜前间隙病变椎间盘处注射600~1200U胶原酶。结果术后随访1个月、3个月,3个月获得最佳疗效,其优、良、中、差率分别为62.3%、32.1%、3.9%、1.7%,优良率94.4%。结论DSA引导下臭氧与胶原酶联合治疗腰椎间盘突出症,在作用机制上优势互补,是一种安全、有效的方法。 相似文献
8.
目的 通过CiteSpace软件分析国内胶原酶治疗腰椎间盘突出症的研究历史和现状。方法 检索1984年至2022年中国知网(CNKI)数据库中关于胶原酶治疗腰椎间盘突出症的文献,应用CiteSpace5.8.R3软件建立可视化科学知识图谱。结果 纳入符合主题的文献1022篇,1994年后发文量逐渐增长,在2005年和2006年年发文量达到最高;发文量排名前3的作者是刘延青、王执民、宋文阁;发文排名前2的省份是山东省和广东省;排名前4的关键词聚类标签是“#0 胶原酶,#1 盘内注射,#2 靶点,#3 臭氧”,关键词突现分析表明“臭氧”具有最大突现强度,“等离子、射频热凝、靶点”突现强度持续至2022年;胶原酶治疗腰椎间盘突出症相关研究经历了持续增长、相对稳定、逐年下降3个阶段;胶原酶的注射方式曾是研究重点,近些年研究热点集中于胶原酶的联合治疗。结论 胶原酶在老年或者难治性腰椎间盘突出症中仍具有研究价值,胶原酶与其他微创介入联合治疗是今后研究热点。 相似文献
9.
Neutral metalloprotease from tendons 总被引:1,自引:0,他引:1
Tendon repair following trauma, rupture, or surgery involves both synthesis and degradation of collagen in order to reweave new collagen bundles in with the old. Using an in situ assay on polyacrylamide gels containing gelatin, we have identified protease activity from tendon tissue and from tendon cells in culture. A population of synovial cells from the epitenon surrounding the tendon as well as the tendon fibroblasts themselves were examined. The cells and the conditioned medium from both cell populations exhibited a major band of gelatin-degrading activity at 70 kdaltons and a minor band of activity at 60 kdaltons. When preparations were reacted with p-aminophenylmercuric acetate (APMA) before electrophoresis, a third band appeared at 63 kdaltons. The main band at 70 kdaltons comigrated with a [35S]methionine-radiolabeled protein band. Inhibitor and pH studies identified the enzymes as neutral metalloproteases requiring disulfide bonds for activity. No proteolytic activity was detected on casein-containing gels, ruling out the presence of stromelysin. Since electrophoresis in the presence of SDS would separate the metalloprotease from the smaller molecular weight inhibitor (TIMP), these in situ assays provide a sensitive screening system for gelatin-degrading enzymes present in tendon without prior removal of TIMP. 相似文献
10.
Summary In order to determine whether interferons (IFNs) play a universal role in terminating the fibrotic response by inhibiting other fibroblast functions in addition to growth and collagen production, we investigated the effect of human recombinant (hu-r) IFN-alpha,-beta, and-gamma on the glycosaminoglycan, fibronectin, and collagenase production of cultured human dermal fibroblasts. Our results show that shortterm (48 h) treatment of confluent fibroblast cultures with hu-r-IFN-alpha2 and hu-r-IFN-beta-ser17 causes a concentration (1 to 1×105 U/ml)-dependent inhibition of glycosaminoglycan production, has no effect on fibronectin production, and markedly increases collagenase production. In contrast, hu-r-IFN-gamma not only causes a concentration-dependent increase in collagenase production but also increases both glycosaminoglycan and fibronectin production. These results demonstrate that IFNs differently regulate fibroblast functions rather than universally inhibit all functions, and show that IFN-alpha and-beta exhibit a broader antifibrotic spectrum that IFN-gamma. 相似文献