全文获取类型
收费全文 | 354篇 |
免费 | 10篇 |
国内免费 | 37篇 |
专业分类
儿科学 | 13篇 |
妇产科学 | 3篇 |
基础医学 | 23篇 |
口腔科学 | 14篇 |
临床医学 | 52篇 |
内科学 | 81篇 |
皮肤病学 | 7篇 |
神经病学 | 6篇 |
特种医学 | 98篇 |
外科学 | 22篇 |
综合类 | 23篇 |
预防医学 | 2篇 |
眼科学 | 4篇 |
药学 | 17篇 |
肿瘤学 | 36篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 2篇 |
2015年 | 6篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 11篇 |
2011年 | 9篇 |
2010年 | 5篇 |
2009年 | 10篇 |
2008年 | 12篇 |
2007年 | 19篇 |
2006年 | 13篇 |
2005年 | 26篇 |
2004年 | 9篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 10篇 |
2000年 | 4篇 |
1999年 | 10篇 |
1998年 | 16篇 |
1997年 | 18篇 |
1996年 | 25篇 |
1995年 | 13篇 |
1994年 | 11篇 |
1993年 | 24篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 14篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 7篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 3篇 |
排序方式: 共有401条查询结果,搜索用时 31 毫秒
61.
62.
Molecular mechanisms of hepatocarcinogenesis in transgenic mouse models of liver cancer 总被引:4,自引:0,他引:4
Overexpression of c-myc and transforming growth factor-alpha (TGF-alpha) has been frequently observed in human hepatocellular carcinoma (HCC),suggesting a pivotal role played by these protooncogenes in liver oncogenesis. In order to investigate the molecular events underlying human hepatic malignant transformation, we have generated c-myc and c-myc/ TGF-alpha transgenic mice that are prone to liver cancer. These transgenic mice develop HCCs with different incidence, kinetics and histopathological features. Indeed, co-expression of c-myc and TGF-alpha transgenes results in a dramatic synergistic effect on liver tumor development when compared with respective single transgenic lines, including a shorter latency period and a more aggressive phenotype. The more malignant histopathological features characteristic of c-myc/ TGF-alpha HCCs are the result of the increased proliferation and reduced apoptosis in this model of liver cancer when compared with single parental lines. Accordingly, c-myc and c-myc/l TGF-alpha transgenic mice display a different molecular pathogenesis of HCC. Importantly, the genetic and molecular mechanisms that are involved in c-myc and c-myc/ TGF-alpha liver cancer development are major oncogenic events in human hepatocarcinogenesis, indicating that these mouse models represent a useful tool to dissect and elucidate the molecular basis of human HCC. 相似文献
63.
Simile MM Pagnan G Pastorino F Brignole C De Miglio MR Muroni MR Asara G Frau M Seddaiu MA Calvisi DF Feo F Ponzoni M Pascale RM 《Carcinogenesis》2005,26(2):417-427
Cell-cycle deregulation is an early event of hepatocarcinogenesis. We evaluated the role of changes in activity of nuclear factor kappaB (NF-kappaB) and some related pathways in this alteration, and the interference of N-(4-hydroxyphenyl)retinamide (HPR), a retinoid chemopreventive for various cancer types, with these molecular mechanisms and the evolution of preneoplastic liver to cancer. Male F344 rats, initiated according to the 'resistant hepatocyte' model of liver carcinogenesis, received weekly 840 nmol of liposomal HPR (SL-HPR)/100 g body wt or empty liposomes, between 5 and 25 weeks after initiation. Inhibition of DNA synthesis and induction of apoptosis occurred in pre-cancerous lesions, 7-147 days after starting SL-HPR, and a decrease in carcinoma incidence and multiplicity was observed 25 weeks after arresting treatment. An increase in NF-kappaB expression and binding activity, and under-expression of the inhibitor kappaB-alpha (IkappaB-alpha) were found in preneoplastic liver and neoplastic nodules, 5 and 25 weeks after initiation, respectively. These lesions also showed low expression of Mat1A and low activity of methionine adenosyltransferase I/III, whose reaction product, S-adenosyl-l-methionine, enhances IkappaB-alpha expression. SL-HPR prevented these changes and induced a decrease in expression of iNos, c-myc, cyclin D1 and Vegf-A genes, that were over-expressed in preneoplastic liver and nodules, and a decrease in Bcl-2/Bax, Bcl-2/Bad and Bcl-xL/Bax mRNA ratios with respect to the lesions of control rats. Liposomes alone did not influence the parameters tested. These results indicate that signal transduction pathways controlled by NF-kappaB, nitric oxide and S-adenosyl-l-methionine are deregulated in pre-cancerous lesions. Recovery from these alterations by SL-HPR is associated with chemoprevention of hepatocarcinogenesis. Overall, these studies elucidate some molecular changes, in early stages of hepatocarcinogenesis, and underline their pathogenetic role. Moreover, they demonstrate a partially new mechanism of HPR chemopreventive effect and indicate the potential clinical relevance of this compound for prevention of hepatocellular carcinoma. 相似文献
64.
Dysregulation of DNA repair pathways in a transforming growth factor alpha/c-myc transgenic mouse model of accelerated hepatocarcinogenesis 总被引:4,自引:0,他引:4
Hironaka K Factor VM Calvisi DF Conner EA Thorgeirsson SS 《Laboratory investigation; a journal of technical methods and pathology》2003,83(5):643-654
Previous work from our laboratory has implicated oxidative DNA damage and genetic instability in the etiology of transforming growth factor-alpha (TGFalpha)/c-myc-associated hepatocarcinogenesis. In contrast, oxidative DNA damage was lower in c-myc single-transgenic mice, consistent with less chromosomal damage and with later and more benign tumor formation. We examined whether defects in the DNA repair pathways contribute to the acceleration of liver cancer in TGFalpha/c-myc mice. A cDNA expression array containing 140 known genes and multiplex RT-PCR were used to compare the basal levels of expression of DNA repair genes at the dysplastic stage. Thirty-five percent (8/23) and 43% (10/23) of DNA repair genes were constitutively up-regulated in 10-week-old TGFalpha/c-myc and c-myc transgenic livers, respectively, compared with wild-type controls. The commonly up-regulated genes were OGG1 and NTH1 of base excision repair; ERCC5, RAD23A, and RAD23B of nucleotide excision repair; and RAD50, RAD52, and RAD54 involved in DNA strand break repair. Additional treatment with a peroxisome proliferator, Wy-14,643, known to increase the level of oxidants in the liver, failed to induce a further increase in the expression level of DNA repair enzymes in TGFalpha/c-myc but not in c-myc or wild-type livers. Moreover, expression of several genes, including Ku80, PMS2, and ATM, was decreased in TGFalpha/c-myc livers, suggesting a fault or inefficient activation of the DNA repair pathway upon induction of oxidative stress. Together, the results show that DNA damage response is attenuated in TGFalpha/c-myc mice, creating a condition that may contribute to acceleration of liver cancer in this model. 相似文献
65.
66.
Lip cancer (140 ICD-9) is a form of oral cancer that has a distinctive global epidemiology. This review summarises global incidence rates for male and female lip cancer with the aid of cancer atlases. High male lip cancer rates are reported for regions of North America (12.7 per 100 000 per annum), Europe (12.0 per 100 000 per annum) and Oceania (13.5 per 100 000 per annum), while it is virtually unknown in parts of Asia. Factors commonly cited as important in the aetiology of lip cancer include solar radiation, tobacco smoking and viruses. An attempt is made to summarise the evidence for factors that may be important in lip carcinogenesis. While incidence rates are generally stable or falling among males worldwide, they are rising in many female populations. The aetiology of the disease is far from established and much information regarding its pathogenesis is based on anecdotal rather than case-controlled epidemiological evidence. The epidemiology of lip cancer supports the proposal that the lip should be considered as a distinct cancer site, rather than being included with other forms of intraoral cancer. 相似文献
67.
Raffaele Garofalo Enrico Ceccarelli Alessandro Castagna Vittorio Calvisi Brody Flanagin Marco Conti Sumant G. Krishnan 《Knee surgery, sports traumatology, arthroscopy》2017,25(7):1989-1994
Purpose
Appropriate surgical management for type V complete acromioclavicular (AC) joint dislocation remains controversial. The purpose of this paper is to retrospectively report the clinical and radiographic outcomes of an open surgical technique consisting for AC joint ligamentous and capsular reconstruction using autologous hamstring tendon grafts and semi-permanent sutures.Methods
Between January 2005 and December 2011, 32 consecutive patients with symptomatic type V complete AC joint dislocation underwent surgical treatment using the same technique. The median time from injury to surgery was 45 days (range 24–90). The average median postoperative clinical and radiographic follow-up time was 30 months (range 24–33). Clinical outcomes measures included the ASES score, the visual analog score (VAS), and subjective patient satisfaction score. Minimum follow-up was 2 years.Results
ASES score increased from a median of 38.2?±?6.2 preoperative to 92.1?±?4.7 postoperatively (p?≤?0.05). The median VAS score improved from 62 mm (range 45–100 mm) preoperatively to 8 mm (range 0–20 mm) at final follow-up (p?≤?0.05). No patient experienced pain or discomfort with either direct palpation of the AC joint or with cross-body adduction. Final radiographs demonstrated symmetric AC joint contour in 25/32 (78%) patients. Seven patients (22%) radiographically demonstrated superior translation of the distal clavicle relative to the superior margin of the acromion but less than 50% of the clavicular width. 30/32 patients (93%) were able to return to their pre-injury level of work and sports activities.Conclusions
This novel surgical technique using a free graft and braided suture for simultaneous coracoclavicular ligament and AC joint capsular reconstruction successfully controls superior and posterior translations after type V AC joint dislocation and minimizes the incidence of persistent postoperative AC joint subluxation.Level of evidence
Retrospective case series, Level IV.68.
69.
Ranjani Ramachandran R Lakshmi Kumar D Ravi K Devika Fathima Rahman DF Wares 《亚太热带病杂志(英文版)》2011,1(1):47-49
ObjectiveTo combine isoniazid (INH) and rifampicin (RIF) in a single media to detect and evaluate multi-drug resistant Mycobacterium tuberculosis (MDR-TB) strains using clinical specimens by direct and indirect drug susceptibility testing (DST).MethodsDrug susceptibility testing for INH and RIF using individual and combined drug media was performed by minimum inhibitory concentration (MIC) method on direct clinical specimens.ResultsThe combined drug media showed complete concordance with individual drug media in the detection of MDR-TB by direct DST method and 89% efficiency with indirect DST method. Susceptibility results were available by 3 weeks after the receipt of clinical specimen using direct DST on combined drug media.ConclusionsCombined drug media can be used as a fast track method in large scale studies warranting detection of MDR-TB. 相似文献
70.
A. Barile G. Lanni L. Conti S. Mariani V. Calvisi A. Castagna F. Rossi C. Masciocchi 《La Radiologia medica》2013,118(1):112-122