全文获取类型
收费全文 | 1623篇 |
免费 | 57篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 75篇 |
儿科学 | 80篇 |
妇产科学 | 65篇 |
基础医学 | 207篇 |
口腔科学 | 12篇 |
临床医学 | 85篇 |
内科学 | 340篇 |
皮肤病学 | 18篇 |
神经病学 | 193篇 |
特种医学 | 8篇 |
外科学 | 90篇 |
综合类 | 11篇 |
预防医学 | 141篇 |
眼科学 | 56篇 |
药学 | 194篇 |
肿瘤学 | 123篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 9篇 |
2021年 | 26篇 |
2020年 | 10篇 |
2019年 | 16篇 |
2018年 | 21篇 |
2017年 | 9篇 |
2016年 | 25篇 |
2015年 | 20篇 |
2014年 | 26篇 |
2013年 | 34篇 |
2012年 | 88篇 |
2011年 | 106篇 |
2010年 | 57篇 |
2009年 | 40篇 |
2008年 | 123篇 |
2007年 | 158篇 |
2006年 | 166篇 |
2005年 | 168篇 |
2004年 | 187篇 |
2003年 | 182篇 |
2002年 | 134篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 9篇 |
1997年 | 10篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1967年 | 1篇 |
1965年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有1698条查询结果,搜索用时 15 毫秒
101.
102.
Karczewicz D Pieńkowska-Machoy E Modrzejewska M Gronkowska J Sylwestrzak Z 《Klinika oczna》2004,106(1-2):19-22
PURPOSE: The aim of the study was to evaluate factors possibly effecting the posterior capsule opacification (PCO), after extra-capsular cataract extraction with the posterior chamber intra-ocular lens (IOL) implantation. Age of patients, refractive errors, technique of cataract extraction, intra- and postoperative complications and coexisting diseases were taken into consideration. In 1992-98 posterior laser Nd:YAG capsulotomy was performed in 222 eyes of 222 patients (134 women and 88 men) previously operated in 1st and IInd Eye Clinic. PCO occurred in 5.8% patients, who underwent cataract extraction in this period, in 5.7% patients operated with phacoemulsification method and in 5.8% patients where extra-capsular cataract extraction with nucleus expulsion was performed. PCO was diagnosed in 12.7% patients at the age below 30, in 17% aged 31-40, in 7.8% aged 41-55 and in 5.1% patients older than 55 years. Among the patients, who developed PCO, in 6.3% myopia was present, in 8% primary open angle glaucoma, 16.6% were treated for diabetes mellitus. In 7.6% eyes the intra-operative cortical clean up was not efficient. CONCLUSION: PCO occurred in young patients (under 40) twice as often as in the other groups of age. Technique of cataract extraction had an influence on the incidence of PCO as well. 相似文献
103.
Garhöfer G Kopf A Polska E Malec M Dorner GT Wolzt M Schmetterer L 《Current eye research》2004,28(5):351-358
PURPOSE: Short term hyperglycemia has previously been shown to induce a blood flow increase in the retina. The mechanism behind this effect is poorly understood. We set out to investigate whether exercise-induced hyperlactatemia may alter the response of retinal blood flow to hyperglycemia. METHODS: We performed a randomized, controlled two-way cross over study comprising 12 healthy subjects, performed a 6-minutes period of dynamic exercise during an euglcaemic or hyperglycaemic insulin clamp. Retinal blood flow was assessed by combined vessel size measurement with the Zeiss retinal vessel analyzer and measurement of red blood cell velocities using bi-directional laser Doppler velocimetry. Retinal and systemic hemodynamic parameters were measured before, immediately after and 10 and 20 minutes after isometric exercise. RESULTS: On the euglycemic study day retinal blood flow increased after dynamic exercise. The maximum increase in retinal blood flow was observed 10 minutes after the end of exercise when lactate plasma concentration peaked. Hyperglycemia increased retinal blood flow under basal conditions, but had no incremental effect during exercise induced hyperlactatemia. CONCLUSIONS: Our results indicate that both lactate and glucose induce an increase in retinal blood flow in healthy humans. This may indicate a common pathway between glucose and lactate induced blood flow changes in the human retina. 相似文献
104.
105.
Kordek A Giedrys-Kalemba S Nikodemski T Bartkowiak E Torbé A Czajka R 《Ginekologia polska》2002,73(8):727-731
Intrauterine and intrapartum infections in newborn infants are still difficult to recognise. The newborn does not manifest the classic clinical signs of infection usually observed in children and adults and up to now there is no good laboratory marker. In the last few years, procalcitonin (PCT) has been found to increase during different inflammatory processes, especially bacterial ones. In this study we analysed the clinical value of PTC in parturient, umbilical cord and newborn blood for predicting perinatal infection. MATERIAL AND METHODS: Thirty parturients with symptoms of intrauterine infection were classified for this study. Blood samples were obtained from the mother, the umbilical cord and the newborn on the second day of life. Serum was stored at -70 degrees C and thawed at the time of analysis. Among the newborns there were 21 infants without and 9 with symptoms and signs of infection. PCT concentration was measured by immunoluminometric assay--LUMI test PCT (BRAHMS). RESULTS: Statistically significant results were found on the second day of life: 5.83 (4.70) ng/ml in ill, 1.41 (0.68) ng/ml in healthy (p < 0.0005). We observed a significant correlation between PCT concentration in mother and umbilical cord blood (y = 0.40x + 1.06; p < 0.05), as well as between umbilical cord blood and venous blood on the second day of life in newborns (y = 0.16x 1.21; p < 0.01). CONCLUSIONS: Measurement of PCT concentration in perinatal period in the mother and in umbilical cord blood of the newborn may be useful for early diagnosis and monitoring of infectious complications in neonates. We need more data on reference ranges of PCT concentration in pregnant women, parturients and umbilical cord blood. 相似文献
106.
Nowak K Waśniewska E Szyfter W 《Otolaryngologia polska. The Polish otolaryngology》2002,56(6):721-725
Three cases of laryngocoele operated in ENT Department University of Medical Sciences in Poznań by an external approach are presented. Role of larynx tomography in diagnosis procedure and surgical technique is emphasised. Origin, classification, diagnosis and treatment methods are discussed. 相似文献
107.
Fritsch C Swietlicki EA Lefebvre O Kedinger M Iordanov H Levin MS Rubin DC 《The Journal of clinical investigation》2002,110(11):1629-1641
The formation of the crypt-villus axis during gut ontogeny requires continued reciprocal interactions between the endoderm and mesenchyme. Epimorphin/syntaxin 2 (epimorphin) is a mesenchymal protein expressed in the fetal gastrointestinal tract during villus morphogenesis. To elucidate its role in gut ontogeny, the epimorphin cDNA was transfected, in sense and antisense orientations, into a rat intestinal myofibroblast cell line, MIC 216. To determine the effects of epimorphin on the epithelium, myofibroblasts were cocultured with the Caco2 cell line. Caco2 cells spread in a simple monolayer over antisense-transfected cells lacking epimorphin. In contrast, sense-transfected myofibroblasts induced Caco2 cells to form compact, round clusters with small lumens. These morphologic differences were preserved in Transwell cocultures in which cell-cell contact was prevented, suggesting that epimorphin's effects were mediated by secreted factor(s). To determine the effects of epimorphin on crypt-villus axis formation in an in vivo model, rat gut endoderm was combined with epimorphin-transfected myofibroblasts and implanted into the chick intracoelomic cavity. The grafts in which epimorphin was overexpressed revealed multiple well-formed villi with crypt-like units, whereas those in which epimorphin expression was inhibited developed into round cystic structures without crypts or villi. Of several potential secreted morphogens, only the expression of bone morphogenetic protein 4 (Bmp4) was increased in the epimorphin-transfected cells. Incubation with noggin partially blocked the transfected myofibroblasts' effects on Caco2 colony morphology. These results indicate that mesenchymal epimorphin has profound effects on crypt-villus morphogenesis, mediated in part by secreted factor(s) including the Bmp's. 相似文献
108.
Potential therapeutic role of cationic peptides in three experimental models of septic shock 总被引:4,自引:0,他引:4 下载免费PDF全文
Giacometti A Cirioni O Ghiselli R Mocchegiani F Del Prete MS Viticchi C Kamysz W ŁEmpicka E Saba V Scalise G 《Antimicrobial agents and chemotherapy》2002,46(7):2132-2136
The therapeutic efficacies of buforin II, indolicidin, and KFFKFFKFF were investigated in three rat models of septic shock: (i) rats injected intraperitoneally with 10 microg of Escherichia coli O111:B4 lipopolysaccharide, (ii) rats given an intraperitoneal injection of 2 x 10(10) CFU of Escherichia coli ATCC 25922, and (iii) rats in which intra-abdominal sepsis was induced via cecal ligation and single puncture. All animals were randomized to receive parenterally isotonic sodium chloride solution, 1 mg of buforin II per kg of body weight, 1 mg of indolicidin per kg, 1 mg of KFFKFFKFF per kg, and 20 mg of imipenem per kg. The main outcome measures were bacterial growth in abdominal exudate and plasma, endotoxin and tumor necrosis factor alpha (TNF-alpha) concentrations in plasma, and lethality. Treatment with all peptides resulted in significant reductions in plasma endotoxin and TNF-alpha concentrations compared with those resulting from the imipenem and saline treatments. On the other hand, imipenem treatment significantly reduced the levels of bacterial growth compared with the reductions achieved with the peptide and saline treatments. All compounds reduced the rates of death compared to that for the controls. Although the peptides demonstrated lower levels of antimicrobial activity than imipenem, they exhibited the dual properties of antimicrobial and antiendotoxin agents. 相似文献
109.
110.