全文获取类型
收费全文 | 251篇 |
免费 | 20篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 4篇 |
妇产科学 | 6篇 |
基础医学 | 29篇 |
临床医学 | 20篇 |
内科学 | 62篇 |
神经病学 | 24篇 |
特种医学 | 8篇 |
外科学 | 42篇 |
综合类 | 2篇 |
预防医学 | 47篇 |
药学 | 11篇 |
中国医学 | 2篇 |
肿瘤学 | 13篇 |
出版年
2022年 | 7篇 |
2021年 | 11篇 |
2020年 | 3篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 9篇 |
2015年 | 6篇 |
2014年 | 4篇 |
2013年 | 9篇 |
2012年 | 14篇 |
2011年 | 12篇 |
2010年 | 8篇 |
2009年 | 10篇 |
2008年 | 19篇 |
2007年 | 13篇 |
2006年 | 17篇 |
2005年 | 6篇 |
2004年 | 15篇 |
2003年 | 9篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 5篇 |
1997年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 7篇 |
1990年 | 7篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 7篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1968年 | 2篇 |
1966年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有271条查询结果,搜索用时 15 毫秒
1.
Moh H Malek Dale E Berger William D Marelich Jared W Coburn Travis W Beck Terry J Housh 《European journal of cardio-thoracic surgery》2006,30(4):637-643
The purpose of this study was to use a meta-analytical technique to examine the efficacy of surgical repair of pectus excavatum on pulmonary function. Studies were retrieved via computerized literature searches, cross-referencing from original and review articles. Inclusion criteria were as follows: (1) reporting quantitative measures of preoperative and postoperative pulmonary function; (2) published in the English language; (3) indexed between January 1960 and September 2005; (4) reporting the duration between which preoperative and postoperative assessments were conducted; and (5) describing the pulmonary assessment procedures. The titles and abstracts of potentially relevant articles were reviewed to determine whether they met the criteria for inclusion. Twelve studies representing 313 pectus excavatum patients met the inclusion criteria and were used for the meta-analysis. Random-effects modeling yielded a mean weighted effect size (ES) for pulmonary function which was statistically nonsignificant (ES=0.08, 95% CI=-0.20 to 0.35; P=0.58). The findings of the present study indicated that surgical repair of pectus excavatum does not significantly improve pulmonary function. These findings, however, may be a result of testing pulmonary function under conditions in which pectus excavatum does not manifest itself. 相似文献
2.
IgG lambda type of monoclonal gammopathy and thin basement membrane nephropathy were established in a middle-aged man examined because of persistent haematuria, lambda light-chain proteinuria and moderately diminished renal function. A 10% level of plasmocytosis was verified by bone-marrow aspiration. The more than 6-year follow-up showed the gammopathy to be benign. The thin basement membrane nephropathy was verified by electronmicroscopic analysis of renal tissue obtained by percutaneous renal biopsy: lamina densa of the glomerular capillaries thinned to 30-100 nm. In spite of the usually good outcome of thin basement membrane nephropathy, in this case it was accompanied by glomerular sclerosis, subsequent destruction of nephrons, hypertensive vascular alterations and a clinical deterioration of the renal function after 4 years. A rebiopsy excluded the possible complications (amyloidosis, non-amyloid immunoglobulin nephropathy, cylinder nephropathy, etc) of light-chain proteinuria. 相似文献
3.
P Hercz P Siklos L Ungár R G Farquharson K Mohári L Kocsár 《European journal of obstetrics, gynecology, and reproductive biology》1987,24(3):189-193
The authors examined the possible role of HPL in the onset of labour. The HPL level of the maternal vein, the umbilical cord vein and artery was compared in vaginal mature (n = 16) and premature (n = 52) deliveries. The HPL concentration was also examined in mature (n = 18) and premature (n = 18) deliveries performed by caesarean section prior to the onset of labour. The results showed that: the serum HPL level in the maternal vein, the umbilical cord vein and artery was lower during the 33rd-36th and the 40th weeks in cases of vaginal delivery compared to elective caesarean section; The artery/vein ratio decreases during labour (A/V X 100 value), indicating that HPL metabolism in the fetus decreases during regular labour pains; The onset of premature labour and delivery was associated with lower HPL levels compared to normal pregnancy. The authors assume that the lower HPL level found in cases of vaginal delivery may be due to reduced placental perfusion, but they do not exclude the possible association of lower HPL concentrations in cases of premature delivery. 相似文献
4.
Erzsébet Lizanecz Eniko T Pásztor Attila Mohácsi Zoltán Papp István Edes Attila Tóth 《Hypertension research》2006,29(3):197-201
Conflicting results are to be found in the literature on the relationship between the M235T polymorphism of the angiotensinogen (AGT) gene and hypertension. The controversy may be due to insufficient numbers of subjects, the variability of the inclusion criteria and the different genotype analysis methods used. We have experienced that the most frequently used, original polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method involves significant uncertainties when the TT genotype is determined, independently of the restriction digestion. To make the determination more accurate, we improved the PCR by designing a new antisense primer containing only one mismatch instead of the two in the original protocol and also by adding DMSO to the PCR reaction mixture. The original and our improved methods were compared by using DNA from 123 patients: parallel determinations resulted in values of 33 MM, 90 MT and 0 TT with the original method and of 33 MM, 56 MT and 34 TT with the improved RFLP protocol. In summary, a plausible explanation for some of the conflicting data published on AGT M235T polymorphism may be that inaccuracies arose during the determination of the genotype. 相似文献
5.
Eva Magyar A. Talerman W. C. de Bruijn Judith Mohácsy H. W. Wouters 《Virchows Archiv : an international journal of pathology》1979,382(2):191-200
Summary Ultrastructural features of muscle spindles were studied in biopsy material from 100 patients suffering from classical rheumatoid arthritis. Thickening of the outer capsule, increased amount of extracellular ground substance within the inner capsule, and marked thickening of the basement membrane of capillary blood vessels supplying the muscle spindles were observed. Chronic inflammatory cells and macrophages were present within the spindles. Changes affecting the intrafusal muscle fibres were also seen. They were manifest as atrophy and degeneration of the intrafusal muscle fibres, absence of the specialised junctional complexes, and of the intercellular bridges, microladders and satellite cells. It is suggested that the changes affecting the intrafusal muscle fibres are probably secondary. Damage to the myelinated nerves was present, while the sensory and motor nerve endings were well preserved.Temporary Research Fellow the Rotterdam Centre for Rheumatic Disease
Present address: Division of Pathology, Department of Obstetrics and Gynaecology, University of Chicago, Chicago, Illinois 60637, USA 相似文献
6.
Cigarette smoke-induced alterations in endothelial nitric oxide synthase phosphorylation: role of protein kinase C. 总被引:1,自引:0,他引:1
L Wagner B Laczy M Tamaskó I Mazák L Markó G A Molnár Z Wagner M Mohás J Cseh A Fekete I Wittmann 《Endothelium》2007,14(4-5):245-255
Endothelial nitric oxide synthase (eNOS) is regulated by phosphorylation of Ser(1177) and Thr(495), which affects NO bioavailability. Cigarette smoke disturbs the eNOS-cGMP-NO pathway and causes decreased NO production. Here the authors investigated the acute effects of cigarette smoke on eNOS phosphorylation, focusing on protein kinases (PKs). Endothelial cell culture was concentration- and time-dependently treated first with cigarette smoke buffer (CSB), then with reduced glutathione (GSH) or various PK inhibitors (H-89, LY-294002, Ro-318425, and ruboxistaurin). eNOS, phospho-Ser(1177)-eNOS, phospho-Thr(495)-eNOS, Akt(PKB), and phospho-Akt protein levels were determined by Western blot. CSB increased the phosphorylation of eNOS at Ser(1177) and more at Thr(495) in a concentration- and time-dependent manner (p < .01, p < .05 versus control, respectively) and resulted in the dissociation of the active dimeric form of eNOS (p < .05). GSH decreased the phosphorylation of eNOS at both sites (p < .05 versus CSB without GSH) and prevented the decrease of dimer eNOS level. CSB treatment also decreased the level of phospho-Ser(473)-Akt (p < .05 versus control). Inhibition of PKA by H-89 did not affect CSB-induced phosphorylation, whereas the PKB inhibitor LY-294002 enhanced it at Ser(1117). The PKC blockers Ro-318425 and ruboxistaurin augmented the CSB-induced phosphorylation at Ser(1177) but decreased phosphorylation at Thr(495) (p < .05 versus CSB). Cigarette smoke causes a disruption of the enzymatically active eNOS dimers and shifts the eNOS phosphorylation to an inhibitory state. Both effects might lead to reduced NO bioavailability. The shift of the eNOS phosphorylation pattern to an inhibitory state seems to be independent of the PKA and phosphoinositol 3-kinase (PI3-K)/Akt pathways, whereas PKC appears to play a key role. 相似文献
7.
The authors analyse the histopathological features and clinical behaviour of 325 superficial (Ta, T1) tumours of 232 patients with bladder cancer. Each of the tumours was treated by TUR using differentiating resection technique and multiple cold biopsy was performed in 197 patients. The recurrence and progression of superficial tumours are examined during the 3-192 months follow up time. It is stressed the role of incomplete TUR in the "recurrence" (tumour persistence). The opinion of the authors is, that superficial bladder tumours can not be considered a homogen group, there are significant differences between Ta and T1 stage in recurrence, neoplastic progression and histopathological features as well. 相似文献
8.
9.
Thrombospondin-1 (TSP-1) is a known inhibitor of angiogenesis; however, a skeletal muscle phenotype of TSP-1 null mice has not been investigated. The purposes of this study were to compare and contrast TSP-1 null and wild-type mice by examining the following: (1) capillarity in the skeletal and cardiac muscles; (2) fibre type composition and oxidative enzyme activity in the hindlimb; and (3) the consequences of TSP-1 gene deletion for exercise capacity. In TSP-1 null mice, maximal running speed was 11% greater and time to exhaustion during submaximal endurance running was 67% greater compared with wild-type mice. Morphometric analyses revealed that TSP-1 null mice had higher ( P < 0.05) capillarity in the heart and skeletal muscle than wild-type mice, whereas no differences for fibre type composition or oxidative enzyme activity were present between the two groups. Cardiac function, as measured by transthoracic echocardiography, revealed no difference in myocardial contractility but greater left ventricular end-diastolic and systolic dimensions, corresponding to an elevated heart mass in the TSP-1 null mice. The results of this study indicate that TSP-1 is an important endogenous negative regulator of angiogenesis that prevents excessive capillarization in the heart and skeletal muscles. The increased capillarity alone was sufficient to increase ( P < 0.05) exercise capacity. These data demonstrate that the capillary-to-muscle interface is a critical factor that limits oxygen transport during exercise. 相似文献
10.
Hyperglycemia increases oxidative stress in various tissues and leads to diabetic cardiovascular complication. Dyslipidemia,
such as an increase in oxidized low-density lipoprotein (LDL), is well recognized in diabetic patients with hyperglycemia.
However, the mechanism by which hyperglycemia causes the increased LDL oxidation remains unclear. Albumin is the most abundant
protein in the circulation, and can function as an antioxidant. Therefore, we examined whether glycoxidative modification
inhibits the antioxidant activity of albumin to LDL oxidation and clarified the mechanism by which this modification may suppress
its antioxidant activity. Human serum albumin (HSA) was incubated in phosphate-buffered saline with and without glucose at
37°C for up to 8 weeks under aerobic conditions (referred to as glycoxidation (goHSA) and oxidation (oHSA), respectively).
Metal chelator-treated, nonoxidative HSA (chHSA) and freshly prepared HSA (fHSA) were used as controls. N
ε-(carboxymethyl)lysine (CML), a glycoxidative product, was determined by enzyme-linked immunosorbent assay. Oxidation was
estimated by measuring the thiols of the HSA molecule. Copper-mediated oxidation of LDL was conducted in the presence or absence
of modified HSAs at 37°C for 6 days. Malondialdehyde and negative charge of LDL were measured. To clarify the mechanism of
reduced antioxidant activity of HSA, we examined firstly the binding activity of modified HSAs to copper, and secondly the
effects of free radical scavengers on the formation of malondialdehyde. CML was formed in goHSA in a time- and concentration-dependent
manner. Both goHSA and oHSA significantly decreased the contents of free thiol groups compared to ch- and fHSAs. The antioxidant
activity of goHSA to LDL oxidation was the lowest among various modified HSAs. The oHSA showed a moderate decrease in antioxidant
activity. The binding activity of go- and oHSAs to copper was lower than that of ch- and fHSAs. The formation of MDA from
LDL oxidation in the presence of goHSA was completely inhibited by Tiron (1,2-dihydroxy-3,5-benzenedisulfonic acid) and superoxide
dismutase. In contrast, catalase and mannitol had no effect. Our results indicate that in vitro glycoxidation of HSA induced
a marked loss of antioxidant activity of this molecule to copper-mediated oxidation of LDL, which may be caused by the generation
of superoxide.
Received: December 17, 2001 / Accepted: June 28, 2002
Acknowledgments The authors thank Drs. Ryoji Nagai and Seikoh Horiuchi (Department of Biochemistry, Kumamoto University School of Medicine,
Kumamoto, Japan) and Drs. Hiroyuki Itabe and Tatsuya Takano (Department of Microbiology and Molecular Pathology, Faculty of
Pharmaceutical Sciences, Teikyo University, Sagamiko, Kanagawa, Japan) for kindly supplying antibodies. We also thank Associate
Professor Takeo Yamaguchi (Department of Chemistry, Faculty of Science, Fukuoka University) for the ESR experiment and Miss
Satoko Nagano for her excellent technical assistance. This work was supported by a Grant-in-Aid from the Ministry of Education,
Science, Sports and Culture of Japan (No. 14570171) and in part by funds from the Central Research Institute of Fukuoka University
(No. 016004).
Correspondence to N. Sakata 相似文献