全文获取类型
收费全文 | 7971篇 |
免费 | 433篇 |
国内免费 | 73篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 179篇 |
妇产科学 | 644篇 |
基础医学 | 913篇 |
口腔科学 | 123篇 |
临床医学 | 905篇 |
内科学 | 1639篇 |
皮肤病学 | 79篇 |
神经病学 | 524篇 |
特种医学 | 240篇 |
外科学 | 1061篇 |
综合类 | 176篇 |
预防医学 | 404篇 |
眼科学 | 72篇 |
药学 | 585篇 |
中国医学 | 114篇 |
肿瘤学 | 766篇 |
出版年
2023年 | 38篇 |
2022年 | 96篇 |
2021年 | 176篇 |
2020年 | 92篇 |
2019年 | 147篇 |
2018年 | 249篇 |
2017年 | 167篇 |
2016年 | 155篇 |
2015年 | 209篇 |
2014年 | 247篇 |
2013年 | 381篇 |
2012年 | 574篇 |
2011年 | 588篇 |
2010年 | 375篇 |
2009年 | 311篇 |
2008年 | 494篇 |
2007年 | 541篇 |
2006年 | 538篇 |
2005年 | 437篇 |
2004年 | 379篇 |
2003年 | 318篇 |
2002年 | 313篇 |
2001年 | 262篇 |
2000年 | 271篇 |
1999年 | 201篇 |
1998年 | 54篇 |
1997年 | 55篇 |
1996年 | 57篇 |
1995年 | 31篇 |
1994年 | 44篇 |
1993年 | 25篇 |
1992年 | 128篇 |
1991年 | 91篇 |
1990年 | 67篇 |
1989年 | 42篇 |
1988年 | 46篇 |
1987年 | 44篇 |
1986年 | 44篇 |
1985年 | 27篇 |
1984年 | 34篇 |
1983年 | 11篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 6篇 |
1979年 | 15篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1973年 | 7篇 |
1972年 | 7篇 |
1971年 | 10篇 |
排序方式: 共有8477条查询结果,搜索用时 15 毫秒
121.
Clonal evolution and lack of cytogenetic response are adverse prognostic factors for hematologic relapse of chronic phase CML patients treated with imatinib mesylate 总被引:2,自引:3,他引:2 下载免费PDF全文
O'Dwyer ME Mauro MJ Blasdel C Farnsworth M Kurilik G Hsieh YC Mori M Druker BJ 《Blood》2004,103(2):451-455
We followed 141 patients treated with imatinib mesylate (> 300 mg) for chronicphase chronic myelogenous leukemia (CML) following failure of treatment with interferon. During 12 months from the start of imatinib mesylate treatment, 96.5% achieved a complete hematologic response, 47.0% achieved a major cytogenetic response, and 32.4% achieved a complete cytogenetic response. The proportion of patients with hematologic relapse was 10.9% at 12 months and 14.6% at 18 months. In a univariate Cox regression analysis, the only pretreatment characteristics that correlated with an increased risk of hematologic relapse were hemoglobin level less than 120 g/L (12 g/dL) (P =.02), increased bands in the peripheral blood (P =.01), and clonal evolution (P <.0001). In a multivariate analysis, an elevated platelet count (P =.03) and clonal evolution (P <.0001) were the only significant factors for hematologic relapse. During treatment, the absence of a major cytogenetic response within the first 6 months also significantly correlated with relapse (P =.03). Notably, patients failing to achieve a major cytogenetic response by 6 months had a significantly higher rate of hematologic relapse (27%) compared with those who achieved a major cytogenetic response by 6 months (3%), and patients with clonal evolution had a significantly higher risk of hematologic relapse (50%) than those without clonal evolution (9%). 相似文献
122.
OBJECTIVE: In utero hematopoietic cell transplantation (IUHCT) typically achieves low-level mixed hematopoietic chimerism. However, the goal of IUHCT is to achieve therapeutic levels of chimerism. We hypothesized that prenatal adoptive immunotherapy might achieve high-level donor chimerism after IUHCT. MATERIALS AND METHODS: BALB/CE15 fetal mice were transplanted with a mixture of C57BL/6 (B6) T-cell-depleted bone marrow (TCD BM) cells and splenocytes from B6 mice presensitized to BALB/C alloantigen. The splenocytes were preincubated in L-leucyl-L-leucine methyl ester (LLME), to minimize graft vs host disease (GVHD). Recipients were followed after birth for donor cell chimerism and GVHD. RESULTS: Full donor hematopoietic chimerism following a single prenatal transplant was achieved in seven transplanted animals. Fully chimeric animals were healthy, without evidence of GVHD, and maintained their engraftment for the duration of the study (48 weeks). However, the addition of presensitized LLME-treated cells decreased survival until weaning relative to TCD BM alone, suggesting that some animals were lost to acute GVHD. Surviving chimeric animals demonstrated increased frequencies of T-regulatory cell populations in their spleen and BM, suggesting that they had successfully suppressed GVHD, allowing survival. CONCLUSIONS: This study represents "proof in principle" that prenatal immunotherapeutic strategies may achieve complete hematopoietic engraftment across full MHC barriers when combined with IUHCT. However, strategies with greater hematopoietic specificity must be developed prior to consideration of clinical application. 相似文献
123.
Phosphatidylinositol 3-kinase is required for insulin-like growth factor-I-induced vascular smooth muscle cell proliferation and migration 总被引:12,自引:0,他引:12
Insulin-like growth factor-I (IGF-I) plays an important role in regulating vascular smooth muscle cell (VSMC) proliferation and directed migration. The mitogenic and chemotactic actions of IGF-I are mediated through the IGF-I receptor, but how the activation of the IGF-I receptor leads to these biological responses is poorly understood. In this study, we examined the role of phosphatidylinositol 3-kinase (PI3 kinase) in mediating the mitogenic and chemotactic signals of IGF-I. IGF-I treatment resulted in a significant increase in phosphotyrosine-associated PI3 kinase activity in cultured primary VSMCs. To determine whether insulin receptor substrate (IRS)-1, -2, or both are involved in IGF-I signaling in VSMCs, cell lysates were immunoprecipitated with either an anti-IRS-1 or an anti-IRS-2 antibody, and the associated PI3 kinase activity was determined. IGF-I stimulation resulted in a significant increase in IRS-1- but not IRS-2-associated PI3 kinase activity, suggesting that IGF-I primarily utilizes IRS-1 to transmit its signal in VSMCs. The IGF-I-induced increase in IRS-I-associated PI3 kinase activity was concentration dependent. At the maximum concentration (50 ng/mL), IGF-I induced a 60-fold increase. This activation occurred within 5 minutes and was sustained at high levels for at least 6 hours. IGF-I also caused a concentration-dependent and long-lasting activation of protein kinase B (PKB/Akt). Inhibition of PI3 kinase activation by LY294002 or wortmannin abolished IGF-I-stimulated VSMC proliferation and reduced IGF-I-directed VSMC migration by approximately 60%. These results indicate that activation of PI3 kinase is required for both IGF-I-induced VSMC proliferation and migration. 相似文献
124.
Rong‐Kuo Lyu Wei‐Hung Chen Sung‐Tsang Hsieh 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2002,6(2):163-166
Abstract: Previous studies have shown that both plasma exchange (PE) and double filtration plasmapheresis (DFPP) are effective treatments in Guillain‐Barré syndrome (GBS). Whether PE and DFPP have similar effects in GBS is not clear. This report compares the therapeutic effectiveness of PE and DFPP in GBS patients treated in 3 major hospitals in northern Taiwan. A total of 102 patients were included in this survey, including 39 with PE (hereafter PE group) and 63 with DFPP (hereafter DFPP group). Both groups showed significant improvement of disability scores after treatment. However, time to onset of effect was shorter (5.6 ± 3.5 versus 7 ± 3.4 days, p < 0.05), and changes of disability scores were more prominent (1.3 ± 0.8 versus 0.8 ± 0.8, p < 0.05) in the PE group than the DFPP group. Mortality and outcome after 6 months were not different between the 2 groups. In conclusion, both PE and DFPP are effective treatments in GBS. PE was superior to DFPP in short‐term effectiveness. The long‐term effectiveness was not different. 相似文献
125.
126.
127.
128.
Fu YC Chi CS Jan SL Wang TM Chen PY Chang Y Chou G Lin CC Hwang B Hsu SL 《Pediatric pulmonology》2003,35(4):263-268
Epidemics of enterovirus 71 infections caused the rapid death of many children in Malaysia in 1997 and in Taiwan in 1998. Pulmonary edema occurred in most of the fatal cases and was considered to be neurogenic. The role of the heart was rarely investigated before. Between January 1998-January 2001, 34 consecutive patients who were admitted to the intensive care unit due to enterovirus infection were studied prospectively. Patients were divided into two groups: group I with pulmonary edema, and group II without pulmonary edema. Comparisons were made between the two groups based upon demographic, neurological, and cardiovascular manifestations. Group I consisted of 11 patients (5 boys, 6 girls; mean age, 22.8 months), and group II of 23 patients (12 boys, 11 girls; mean age, 28.8 months). There were no significant differences between the two groups in comparing sex, age, body weight, neurological severity, intracranial pressure, cell count, protein and glucose levels in cerebral spinal fluid, and blood pressure. All group I patients had left ventricular dysfunction, and their ejection fractions were significantly lower than those of patients in group II (37 +/- 11% vs. 75 +/- 6%, P < 0.001). Group I heart rates were higher than those of group II (175 +/- 24 vs. 137 +/- 25, P < 0.001). In group I, 9 patients who received conventional treatment died, and the only two survivors received left ventricular assist devices. In conclusion, the pulmonary edema of fulminant enterovirus 71 infection is associated with left ventricular failure. Left ventricular function is the major determinant of outcome. Early recognition of heart failure and aggressive cardiac intervention are life-saving. Pediatr Pulmonol. 2003; 35:263-268. 相似文献
129.
Previous study demonstrated that the percentage of circulating endothelial progenitor cells was reduced in patients with coronary
artery disease. However, the relationship of the percentage of circulating endothelial progenitor cells to the severity of
coronary artery disease has not been investigated. The percentages of circulating endothelial progenitor cells were measured
in 78 consecutive patients with unstable angina, as well as in 32 healthy volunteers. Dual-stained cells expressing CD34 and
vascular endothelial growth factor receptor-2 were judged to be endothelial progenitor cells and were analyzed using flow
cytometry. On stepwise multiple linear regression analysis, the percentages of circulating endothelial progenitor cells were
independently decreased in patients with unstable coronary artery disease compared with those in the healthy volunteers (P < 0.05). Among patients with unstable coronary artery disease, the percentage of patients with at least one occluded vessel
was significantly higher in patients with multi-vessel disease than in patients with single-vessel disease (P < 0.04). On stepwise multiple linear regression analysis, the percentages of circulating endothelial progenitor cells were
independently decreased in patients with multi-vessel coronary artery disease compared with those in patients with single-vessel
coronary artery disease (P < 0.03). Among patients with unstable coronary artery disease, the percentage of circulating endothelial progenitor cells
was significantly related to the severity of coronary artery disease. 相似文献
130.
Lin C Lin MT Hsieh DY Chao YF Yeh SL Wu MS Lin JT Lee PH Chang KJ Chen WJ 《Hepato-gastroenterology》2003,50(54):1821-1824
BACKGROUND/AIMS: Central vein catheters for patients receiving total parenteral nutrition have a high incidence of colonized catheters and catheter-related bloodstream infections. However, the actual incidence and bacterial pattern have not been well studied. This study was undertaken to investigate the difference in bacteriology between colonized catheters and catheter-related bloodstream infections. METHODOLOGY: From January 1997 to March 1998, 354 patients receiving total parenteral nutrition were included in this study. The patients ranged in age from 49 to 80 years, 151 women and 203 men. Colonized catheters and catheter-related bloodstream infections were defined. RESULTS: The culture was performed in 249 catheter tips (249 of 614, 40.6%). Sixty tips were found to have organisms. The organisms cultured from colonized catheters were Gram(+) aerobic bacteria (34, 56.7%), fungi (14, 23.3%), and Gram(-) aerobic bacteria (12, 20%). The organisms cultured from catheter-related bloodstream infections were fungi (16, 64%), Gram(-) aerobic bacteria (5, 20%), and Gram(+) aerobic bacteria (4, 16%). Dermatogenic infection in colonized catheters should be stressed, but systemic fungal infection in catheter-related bloodstream infections should be emphasized. CONCLUSIONS: A striking difference exists in bacterial species between colonized catheters and catheter-related bloodstream infections. Further studies on different treatment strategy for colonized catheters and catheter-related bloodstream infections should be undertaken. The combined approach of a total parenteral nutrition team, sterile protocols, and early diagnosis of fungemia should be advocated for the total parenteral nutrition patients. 相似文献