全文获取类型
收费全文 | 934篇 |
免费 | 74篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 50篇 |
妇产科学 | 16篇 |
基础医学 | 93篇 |
口腔科学 | 16篇 |
临床医学 | 60篇 |
内科学 | 247篇 |
皮肤病学 | 14篇 |
神经病学 | 58篇 |
特种医学 | 37篇 |
外科学 | 308篇 |
综合类 | 10篇 |
预防医学 | 7篇 |
眼科学 | 15篇 |
药学 | 20篇 |
肿瘤学 | 20篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 11篇 |
2021年 | 25篇 |
2020年 | 16篇 |
2019年 | 27篇 |
2018年 | 27篇 |
2017年 | 29篇 |
2016年 | 35篇 |
2015年 | 49篇 |
2014年 | 49篇 |
2013年 | 73篇 |
2012年 | 69篇 |
2011年 | 65篇 |
2010年 | 44篇 |
2009年 | 51篇 |
2008年 | 60篇 |
2007年 | 62篇 |
2006年 | 63篇 |
2005年 | 59篇 |
2004年 | 58篇 |
2003年 | 36篇 |
2002年 | 60篇 |
2001年 | 14篇 |
2000年 | 9篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有1010条查询结果,搜索用时 15 毫秒
1.
2.
Orbital hydatid cyst is rare. We present a case with CT and MRI, emphasizing the superiority of the latter.
Received: 19 August 1996 Accepted: 9 September 1996 相似文献
3.
Undar A Zapanta CM Reibson JD Souba M Lukic B Weiss WJ Snyder AJ Kunselman AR Pierce WS Rosenberg G Myers JL 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2005,51(1):56-59
Unreliable quantification of flow pulsatility has hampered many efforts to assess the importance of pulsatile perfusion. Generation of pulsatile flow depends upon an energy gradient. It is necessary to quantify pressure flow waveforms in terms of hemodynamic energy levels to make a valid comparison between perfusion modes during chronic support. The objective of this study was to quantify pressure flow waveforms in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE) levels in an adult mock loop using a pulsatile ventricle assist system (VAD). A 70 cc Pierce-Donachy pneumatic pulsatile VAD was used with a Penn State adult mock loop. The pump flow rate was kept constant at 5 L/min with pump rates of 70 and 80 bpm and mean aortic pressures (MAP) of 80, 90, and 100 mm Hg, respectively. Pump flows were adjusted by varying the systolic pressure, systolic duration, and the diastolic vacuum of the pneumatic drive unit. The aortic pressure was adjusted by varying the systemic resistance of the mock loop EEP (mm Hg) = (integral of fpdf)/(integral of fdt) SHE (ergs/cm3) = 1,332 [((integral of fpdt)/(integral of fdt))--MAP] were calculated at each experimental stage. The difference between the EEP and the MAP is the extra energy generated by this device. This difference is approximately 10% in a normal human heart. The EEP levels were 88.3 +/- 0.9 mm Hg, 98.1 +/- 1.3 mm Hg, and 107.4 +/- 1.0 mm Hg with a pump rate of 70 bpm and an aortic pressure of 80 mm Hg, 90 mm Hg, and 100 mm Hg, respectively. Surplus hemodynamic energy in terms of ergs/cm3 was 11,039 +/- 1,236 ergs/cm3, 10,839 +/- 1,659 ergs/cm3, and 9,857 +/- 1,289 ergs/cm3, respectively. The percentage change from the mean aortic pressure to EEP was 10.4 +/- 1.2%, 9.0 +/- 1.4%, and 7.4 +/- 1.0% at the same experimental stages. Similar results were obtained when the pump rate was changed from 70 bpm to 80 bpm. The EEP and SHE formulas are adequate to quantify different levels of pulsatility for direct and meaningful comparisons. This particular pulsatile VAD system produces near physiologic hemodynamic energy levels at each experimental stage. 相似文献
4.
Yaylim I Isbir T Oztürk O Turna A Işitmangil T Zonüzi F Camlica H 《Cancer Genetics and Cytogenetics》2002,134(2):118-122
A potential molecular marker associated with cancer susceptibility as well as metastasis, prognosis and adverse survival, is the L-myc gene. The studies of lung cancer patients from different populations have yielded controversial results. We studied 64 nonsmall cell lung cancer (NSCLC) patients and 37 healthy controls of Turkish origin for L-myc gene polymorphism. Our aim was to test the hypothesis that there was association between L-myc S allele in NSCLC and predisposition to the disease and TNM stage indicating tumor size, node classification and metastasis. Polymerase chain reaction restriction fragment length polymorphism and agarose gel electrophoresis were used to determine the L-myc oncogene genotypes. We found no significant difference, both in the distribution of the LL, LS and SS genotypes and in the allelic frequencies, between the patient group and the control group; that is, the frequencies of L-myc alleles were, L and S, 0.59 and 0.41, 0.60 and 0.40, respectively. Our data between the patient group and the control group; that is, the frequencies of L-myc alleles were, L and S, 0.59 and 0.41, 0.60 and 0.40, respectively. Our data concerning age, sex, size of tumors, histological type of tumors showed no significant association with L-myc genotype. However, a higher frequency of L-myc S allele in the squamous cell carcinoma compared to other histological groups was found, although this difference was not statistically significant. No association was found between the L-myc RFLP and increased risk of metastasis either to the lymph nodes or to other organs. Our results suggested that L-myc gene polymorphism was not a suitable prognostic marker of metastatic development in Turkish NSCLC patients. 相似文献
5.
Perforation of the uterus is rare but potentially fatal. During puerperium when the uterus is small and its wall is thin, the risk of perforation increases. We report a rare complication from an intrauterine contraceptive device (IUD) which caused deviation of the right ureter in a 31-year-old woman who presented with complaints of insomnia and abdominal pain. Our case shows that perforation of the uterus by an IUD can cause a silent urological complication. The possibility of ureteral involvement and displacement should be kept in mind in a woman in whom a missing IUD is encountered. 相似文献
6.
7.
Rodrigues Alfredo M. V. Özak Argun Akif Silva Luis M. H. Boxshall Geoffrey Allan 《Parasitology research》2018,117(12):3843-3850
Parasitology Research - A new species of caligid copepod, Caligus mulli n. sp., is described based on specimens collected from surmullet Mullus surmuletus Linnaeus from Atlantic waters off the... 相似文献
8.
9.
Yasar Kucukardali Oral Oncul Saban Cavuslu Mehmet Danaci Semra Calangu Hakan Erdem Ayse Willke Topcu Zuhal Adibelli Murat Akova Emel Azak Karaali Ahmet Melih Ozel Zahit Bolaman Bulent Caka Birsen Cetin Erkan Coban Oguz Karabay Cagla Karakoc Mehmet Akif Karan Selda Korkmaz Gulsen Ozkaya Sahin Alaaddin Pahsa Fatma Sirmatel Emrullah Solmazgul Namik Ozmen Ilyas Tokatli Cengiz Uzun Gulsen Yakupoglu Bulent Ahmet Besirbellioglu Hanefi Cem Gul 《International journal of infectious diseases》2008,12(1):71-79
OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies. 相似文献
10.