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排序方式: 共有675条查询结果,搜索用时 15 毫秒
1.
E. Waris M. Pakkanen K. Lassila P. Törmälä Y. T. Konttinen R. Suuronen N. Ashammakhi 《European journal of plastic surgery》2003,26(7):350-355
A wide variety of biological and alloplastic injectable biomaterials are available for soft tissue augmentation, but the ideal material has not yet been discovered. Biological materials such as collagen and hyaluronan yield temporary results, while injectable alloplasts are apt to cause varying degrees of foreign body reactions that may result in lumps and chronic inflammation.We present two cases (one is the first filed case in the world) of migratory subcutaneous inflammatory masses secondary to injection of acrylic hydrogel (DermaLive), which is an alloplastic biomaterial recently introduced into the market in Europe. Histology revealed foreign body reaction to acrylic hydrogel with granuloma formation containing multinucleated giant cells. Following this, further reports on complications have been reported elsewhere in Europe. The use and development of injectable materials, as well as alternative methods and future directions are reviewed. 相似文献
2.
Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols 总被引:47,自引:7,他引:47
In order to study the biological activities of tea preparations and
purified tea polyphenols, their growth inhibitory effects were investigated
using four human cancer cell lines. Growth inhibition was measured by
[3H]thymidine incorporation after 48 h of treatment. The green tea
catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin
(EGC) displayed strong growth inhibitory effects against lung tumor cell
lines H661 and H1299, with estimated IC50 values of 22 microM, but were
less effective against lung cancer cell line H441 and colon cancer cell
line HT-29 with IC50 values 2- to 3- fold higher.
(-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was
even less effective. Preparations of green tea polyphenols and theaflavins
had higher activities than extracts of green tea and decaffeinated green
tea. The results suggest that the growth inhibitory activity of tea
extracts is caused by the activities of different tea polyphenols. Exposure
of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the
induction of apoptosis as determined by an annexin V apoptosis assay,
showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM
of these compounds, the apoptosis indices were 82, 76 and 78%,
respectively. Incubation of H661 cells with EGCG also induced a
dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused
apoptosis in a manner similar to that caused by EGCG. The EGCG-induced
apoptosis in H661 cells was completely inhibited by exogenously added
catalase (50 units/ml). These results suggest that tea polyphenol-induced
production of H2O2 may mediate apoptosis and that this may contribute to
the growth inhibitory activities of tea polyphenols in vitro.
相似文献
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Acute appendicitis: CT and US correlation in 100 patients 总被引:18,自引:1,他引:18
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DA O'Sullivan VE Torres PA Gabow SN Thibodeau BF King EJ Bergstralh 《American journal of kidney diseases》1998,32(6):976-983
Recent experiments in cultured cyst epithelial cells from kidneys of patients with autosomal dominant polycystic kidney disease (ADPKD) have shown that the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is present in the apical surface of these cells and mediates chloride (Cl-) and fluid secretion in vitro. To determine whether the presence of CF with the expression of mutated CFTR proteins modifies cyst formation in ADPKD, we studied a large family with both inherited diseases. ADPKD in this family is linked to PKD1. The family is composed of 26 members; 11 members with ADPKD, 4 members with CF, and 2 members with both diseases. Renal volumes measured by computerized tomography (CT), calculated creatinine clearances, and other clinical parameters in the family members with ADPKD and CF were compared with those in the family members with ADPKD alone, as well as to a large population of patients with ADPKD. The patients with CF and ADPKD, but not the CF heterozygote carriers with ADPKD, had less severe polycystic kidney and liver disease, as indicated by normal renal function; smaller renal volume, even when corrected for height and body surface area; and the absence of hypertension and liver cysts. These observations suggest that the coexistence of CF may reduce the severity of ADPKD. 相似文献
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9.
目的 通过凝血酶对成骨细胞的增殖及分化作用的研究来探讨受体介导的凝血酶的功能.方法 原代成骨细胞分别取自于蛋白酶激活受体(protease-activated receptor,PAR)-1敲除鼠和野生对照鼠的头颅骨.并利用凝血酶,人工合成的PAR-1或PAR-4特异性激活短肽对细胞进行处理,通过对5.溴-2-脱氧尿嘧啶的嵌入及细胞碱性磷酸酶活性的测定探讨PAR-1或PAR-4激活对细胞增殖和分化的影响.结果 在野生鼠成骨细胞,凝血酶及PAR-1激活肽均能促进的细胞增殖和降低碱性磷酸酶的活性,但PAR-4激活肽却无这些作用.然而在PAR-1 敲除鼠的成骨细胞无论是凝血酶还是PAR-4激活肽均不能改变细胞的增殖及碱性磷酸酶的活性.结论 本研究结果 表明凝血酶促进成骨细胞增殖及抑制其分化是通过PAR-1介导的.其他凝血酶受体并不具有此作用. 相似文献
10.
Improving cell engraftment with tissue engineering 总被引:3,自引:0,他引:3
Cardiac cell therapy has not yet resulted in long-term clinical benefits or major recovery of myocardial function in humans. To date, most of the cardiac effects of cell-based therapy are believed to be mediated by a local angiogenic response rather than by the formation of neosyncytial contractile units such as had initially been hoped for. Therefore, repopulation of the ischemic or infarcted heart with progenitor cells that have vasculogenic potential may be an important mechanism to improve contractile function, both in the presence of viable and nonviable myocardium. This constitutes a focus within scientific reach; however, the low engraftment and viability of progenitor cells after transplantation necessitate the exploration of novel delivery techniques. Because biomaterials have the capacity to improve cell retention, survival, and differentiation, tissue engineering is now being explored as an approach to support cell-based therapies and enhance their efficacy. In this article, we address current progress made in tissue engineering to support cell therapy for the heart, and summarize our work in the development of biomaterials toward improving cell delivery and vascularization of ischemic tissue. 相似文献