全文获取类型
收费全文 | 1438篇 |
免费 | 104篇 |
国内免费 | 9篇 |
学科分类
医药卫生 | 1551篇 |
出版年
2023年 | 12篇 |
2022年 | 18篇 |
2021年 | 69篇 |
2020年 | 36篇 |
2019年 | 40篇 |
2018年 | 29篇 |
2017年 | 35篇 |
2016年 | 32篇 |
2015年 | 35篇 |
2014年 | 72篇 |
2013年 | 76篇 |
2012年 | 91篇 |
2011年 | 90篇 |
2010年 | 68篇 |
2009年 | 60篇 |
2008年 | 99篇 |
2007年 | 106篇 |
2006年 | 66篇 |
2005年 | 79篇 |
2004年 | 57篇 |
2003年 | 65篇 |
2002年 | 37篇 |
2001年 | 27篇 |
2000年 | 30篇 |
1999年 | 32篇 |
1998年 | 14篇 |
1997年 | 8篇 |
1996年 | 13篇 |
1993年 | 4篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 8篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1972年 | 3篇 |
1969年 | 6篇 |
1968年 | 3篇 |
排序方式: 共有1551条查询结果,搜索用时 78 毫秒
31.
Kasper C Sayer HG Mügge LO Schilling K Scholl S Issa MC Höffken K 《Bone marrow transplantation》2004,33(1):65-69
In this open single-centre phase II study, MMF was added on day +10 after allogeneic transplantation to standard immunosuppressive prophylaxis consisting of cyclosporine and methotrexate to decrease the incidence of GvHD. In all, 30 patients aged 20-59 years with advanced haematological malignancies received an unmanipulated blood-stem-cell graft (median of 8.5 x 10(6) CD34(+) and 349 x 10(6) CD3(+) cells per bodyweight) from matched unrelated (n=26), or mismatched donors (n=4). Prior to transplantation, 13 patients underwent fractionated total body irradiation and cyclophosphamide, one patient additional etoposide. In all, 16 patients received reduced conditioning of fludarabin, busulfan, and antithymocyte globulin. All patients engrafted in a median of 12 days, and 19 developed acute GvHD>/=II, including two patients with GvHD III and three with GvHD IV. Subsequently, nine patients developed limited and two patients extensive chronic GvHD. With a median follow-up of 28 months, the overall survival is 53.3% and disease-free survival 50%, respectively. Only two deaths were due to GvHD IV. Out of 13 patients, 10 being CMV IgG positive became positive for pp65. In conclusion, this MMF schedule seems to be safe and feasible in the prophylaxis of severe acute GvHD for high-risk patients, restricted by an increased risk for reactivating CMV in seropositive patients. 相似文献
32.
Ziad F. Issa 《Journal of interventional cardiac electrophysiology》2008,22(1):71-74
We report the case of a 65-year-old man with chronic atrial fibrillation (AF) and severe ischemic cardiomyopathy who underwent implantation of a prophylactic single-chamber implantable cardioverter-defibrillator (ICD). The patient experienced inappropriate ICD therapies due to oversensing of pectoral muscle myopotential secondary to reversal of the defibrillator coil terminal pins in the ICD header. Recognizing this possibility is important to avoid misinterpretation of spontaneous oversensing as hardware failure (e.g., lead fracture or insulation breech) and potentially unnecessary ICD system surgical intervention, including lead extraction. 相似文献
33.
34.
35.
Veldtman Gruschen Possner Mathias Mohty Dania Issa Ziyad Alsaleh Monerah AlMarzoog AlJuhara Thaar Emmanual Shisamma Salam Yezan AlHabdan Mohammed Saleh Alsaied Tarek Rathod Rahul H. Siblini Ghassan Vriz Olga 《The international journal of cardiovascular imaging》2021,37(9):2651-2660
The International Journal of Cardiovascular Imaging - Abnormal atrial mechanics in biventricular circulations have been associated with elevated left heart filling pressures. Similar associations... 相似文献
36.
Expression of an exogenous eukaryotic DNA methyltransferase gene induces transformation of NIH 3T3 cells. 总被引:13,自引:4,他引:13 下载免费PDF全文
J Wu J P Issa J Herman D E Bassett Jr B D Nelkin S B Baylin 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(19):8891-8895
Abnormal regional increases in DNA methylation, which have potential for causing gene inactivation and chromosomal instability, are consistently found in immortalized and tumorigenic cells. Increased DNA methyltransferase activity, which is also a characteristic of such cells, is a candidate to mediate these abnormal DNA methylation patterns. We now show that, in NIH 3T3 mouse fibroblasts, constitutive overexpression of an exogenous mouse DNA methyltransferase gene results in a marked increase in overall DNA methylation which is accompanied by tumorigenic transformation. These transformation changes can also be elicited by dexamethasone-inducible expression of an exogenous DNA methyltransferase gene. Our findings provide strong evidence that the increase in DNA methyltransferase activity associated with tumor progression could be a key step in carcinogenesis and provide a model system that can be used to further study this possibility. 相似文献
37.
38.
Kashif B. Naeem Mahmood Y. Hachim Ibrahim Y. Hachim Ayman Chkhis Rajesh Quadros Haifa Hannawi Issa Al Salmi Fahdah Alokaily Suad Hannawi 《Saudi medical journal》2020,41(11):1204
Objectives:To evaluate acute cardiac injury in COVID-19 patients and its association with adverse outcomes including mortality in the United Arab Emirates (UAE) population.Methods:A retrospective study conducted between February and June 2020 in Dubai, UAE, for all laboratory-confirmed Coronavirus disease-19 patients. Demographic, clinical, laboratory, radiological, and clinical outcomes were compared between patients with and without acute cardiac injury.Results:During the study period, 203 patients were included, of which, 44 (21.7%) had evidence of acute cardiac injury. Compared with patients without acute cardiac injury, patients with acute cardiac injury were: older, had more shortness of breath, diabetes, hypertension, and more bilateral airspace shadowing on admission chest radiography. These patients also had a higher neutrophil count, C-reactive protein, procalcitonin, ferritin, D-dimers and lactate dehydrogenase but lower lymphocyte count. Regarding outcomes, these patients had higher intensive care admissions; a higher rate of complications including acute kidney and liver injury, acidosis, septic shock, acute respiratory distress syndrome, needed more mechanical ventilation, and had a significantly higher risk of death.Conclusion:Acute cardiac injury is common among Coronavirus disease-19 patients. These patients present with higher comorbidities, have high inflammatory markers and have greater risk for in-hospital multi-organ damage, need for mechanical ventilation, and death. Prompt full assessment and intervention are recommended. 相似文献
39.
Lamoussa Paul Ouattara Souleymane Sanon Valérie Mahiou-Leddet Adama Gansané Béatrice Baghdikian Abdoulaye Traoré Issa Nébié Alfred S. Traoré Nadine Azas Evelyne Ollivier Sodiomon Bienvenu Sirima 《Parasitology research》2014,113(1):405-416
Malaria remains a major public health problem due to the emergence and spread of Plasmodium falciparum drug resistance. There is an urgent need to investigate new sources of antimalarial drugs which are more effective against Plasmodium falciparum. One of the potential sources of antimalarial drugs is traditional medicinal plants. In this work, we studied the in vitro antiplasmodial activity of chloromethylenic, methanolic, and MeOH/H2O (1/1) crude extracts and decoction obtained from eight medicinal plants collected in Burkina Faso and of total alkaloids for five plants. Extracts were evaluated in vitro for efficacy against Plasmodium falciparum strain K1, which is resistant to chloroquine, pyrimethamine and proguanil using the fluorescence-based SYBR Green I assay. The antiproliferative activity on human-derived hepatoma cell line HepG2 and Chinese hamster ovary (CHO) cells was evaluated using the 3-[4,5-dimethylthyazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test in order to determine the selectivity index. Among the plant extracts tested for in vitro antiplasmodial activity, 16 were considered to be inactive (with IC50?>?10 μg/ml), six showed a moderate activity (5?<?IC50?≤?10 μg/ml), and six were found to have a good in vitro activity with IC50 value?≤?5 μg/ml. The highest antiplasmodial activity was found for extracts from: the alkaloid leaf extract and the chloromethylenic extracts of Combretum fragrans (IC50?=?3 μg/ml, IC50?=?5 μg/ml), the total alkaloids and the chloromethylenic leaf extracts of Combretum collinum (IC50?=?4 μg/ml), the MeOH/H2O leaf extract of Terminalia avicennioides (IC50?=?3.5 μg/ml), and the alkaloid leaf extract of Pavetta crassipes (IC50?=?5 μg/ml). Three other extracts showed moderate antiplasmodial activity (5?<?IC50?≤?10 μg/ml): Terminalia avicennioides and Combretum fragrans methanolic extracts and Acacia kirkii alkaloid leaf extract (IC50?=?6.5, 9 and 10 μg/ml respectively). The Terminalia avicennioides crude MeOH/H2O (80:20 v/v) extract of the leaves was submitted to a successive liquid/liquid extraction with ethylacetate and n-butanol respectively. The extracts were investigated for in vitro antiplasmodial activity and antioxidant properties using DPPH●, ABTS+ and FRAP methods. The ethylacetate extract showed the best antiplasmodial activity (7 μg/ml) and the active constituent was isolated as ellagic acid by bioguided fractionation with an IC50?=?0.2 μM on Plasmodium falciparum and SI?=?152. Besides, Terminalia avicennioides leaf extract and ellagic acid showed a good antioxidant activity. Our finding confirms the importance of investigating the antimalarial activity of plant species used in traditional medicine. Overall, two plants belonging to the Combretaceae family, Combretum fragrans and Combretum collinum appeared to be the best candidates and will be further investigated for their antiplasmodial properties, in order to isolate the molecules responsible for the antiplasmodial activity. 相似文献
40.
Thiago Ninck Valette Silvia Moreira Ayub-Ferreira Luiz Alberto Benvenuti Victor Sarli Issa Fernando Bacal Paulo Roberto Chizzola Germano Emilio Concei??o Souza Alfredo Inácio Fiorelli Ronaldo Honorato Barros dos Santos Edimar Alcides Bocchi 《Arquivos brasileiros de cardiologia》2014,102(5):505-509