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21.
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization.  相似文献   
22.
23.
《Radiography》2020,26(4):e195-e200
IntroductionAdverse events in radiology are quite rare, but they do occur. Radiation safety regulations and the law obligate organizations to report certain adverse events, harm and near misses, especially events related to patients' health and safety. The aim of this study was to describe and analyse incidents related to radiation safety issues reported in Finland.MethodsThe data were collected from incident reports documented by radiology personnel concerning notifications of abnormal events in medical imaging made to the Radiation and Nuclear Safety Authority between 2010 and 2017. During these eight years, 312 reports were submitted. Only events reported from radiology departments were included; nuclear medicine, radiotherapy and animal radiology cases were excluded. The final number of reports was 293 (94%).ResultsThe majority of the 293 approved reports were related to computed tomography (CT, 68.3%) and to X-ray examinations (27.6%). Altogether 82.9% of those irradiated were adults, most of whom were exposed to unnecessary radiation through CT (86.5%), 5.5% were children, and 4.4% pregnant women. The most common effective dose of unnecessary radiation was 1 mSv or less (89.7% of all examinations). The highest effective doses were reported in CT (from under 1 mSv–20 mSv and above). The reasons for the adverse events were incorrect identification (32%), incorrect procedure, site or side (30%); and human errors or errors of knowledge (20%).ConclusionAdverse events occurred especially in CT examinations. It is important to collect and analyse incident data, assess the harmful events, learn from them and aim to reduce adverse events.Implications for practiceThis study emphasizes the need for radiological personnel to obtain evidence-based information on adverse events and focus on training to improve patient safety.  相似文献   
24.
当利用放射线对胸部恶性肿瘤进行治疗时,位于纵隔的心脏会不可幸免受到照射,从而诱发放射性心脏损伤(radiation-induced heart disease, RIHD)。随着手术以及放化疗技术的提升,肿瘤患者生存时间得到延长,使得RIHD这一放疗远期并发症被越来越多的报道。因此,学者们对于RIHD的研究逐渐升温。目前国内外学者关于该疾病尚未形成统一的认识,临床上缺乏有效阻止其发生的方法。动物模型研究可为临床该疾病治疗及预防提供可靠证据,为此本文回顾分析近年来放射性心脏损伤动物模型实验研究情况,旨在为后续实验开展及临床应用提供参考。  相似文献   
25.
同步放化疗是不可手术局部晚期食管癌的标准治疗模式,国际推荐根治性放疗剂量为50.0~50.4Gy,但中国食管癌与西方国家在病理类型、生物学行为等方面大有不同,行根治性放疗剂量仍倾向于60Gy。增加放疗剂量能否带来生存获益成为临床亟待解决的问题。有研究认为高剂量放疗可提高局控率、改善生存,但也有研究认为提高剂量未能带来生存获益,且可增加不良反应事件发生率。因此,本文就食管癌根治性放疗剂量对预后的影响进行探讨,并通过放化疗后疗效评估对放疗剂量做出适当调整,以期达个体化放疗。  相似文献   
26.
PurposePhysician burnout is reported in more than one out of every 2 practicing clinicians and is just as prevalent in training physicians. Burnout severity is also associated with increasing levels of financial debt. Medical professionals are notable for their high and increasing levels of debt; despite this, financial literacy is poor among physicians, and financial education is largely absent from medical education. Radiation oncologists (ROs) are no different in this regard, with 33% of residents reporting high levels of burnout symptoms, 33% carrying >$200,000 of educational debt, and 75% reporting being unprepared to handle future financial decisions. To fill this gap, we reviewed the basic tenets of personal financial health for the early career RO.Methods and materialsThe core concept of financial independence (FI) is introduced, and we review 4 basic tenets of personal financial health for the young medical professional: debt, behavior, investment, and asset protection strategies.ResultsFI is achieved by saving until the desired quality of life can be maintained, independent of employment income. Debt strategy involves minimizing debt accrual, understanding student loans, and having a debt management plan. Behavioral strategy involves setting financial goals, calculating worth and a savings rate, budgeting, and frugal living. The basics of investing include asset allocation, diversification, rebalancing, and minimizing expenses. Finally, asset protection includes insuring against catastrophic events with disability, life, health, liability, and property insurance.ConclusionsHealthy financial practices can lead to FI and may facilitate professional and personal freedoms with the goal of mitigating burnout-associated stressors. The tenets of strong financial health for ROs in the early stages of their career include sound debt, behavioral, investment, and asset protection strategies. Furthermore, initial and continuing financial education is an overlooked but important curriculum component. ROs with their financial houses in order can devote more resources to learning and practicing good medicine while living healthy, rewarding lives.  相似文献   
27.
Paul Lombardo   《Radiography》2006,12(4):332-338
The Australian higher education system is in a state of great change. The Federal education minister, Dr Brendan Nelson, has indicated that he intends to continue introducing far-reaching reforms that will impact significantly on how universities conduct teaching and research. The future allocation of government funding for university programs, including those in medical radiation, will have a significant effect on how those programs are delivered and could even determine whether programs remain viable. There will be a financial imperative for academic departments to strengthen research activity and to obtain funding from non-government sources, such as full-fee paying students, in order to generate enough income to cover program delivery. Medical radiation education in Australia is also facing many other challenges. Some of these are longstanding, such as the high cost of medical radiation program delivery, poor levels of research activity and difficulty in recruiting and retaining academic staff. Other problems have arisen recently, such as increased competition for students and a critical shortage of available training placements in clinical practice. The aim of this paper is to raise and explore these issues from a university perspective.  相似文献   
28.
目的研究不同剂量60Co γ射线辐照全血在保存期内红细胞CR1分子数目的变化.方法应用酶联法定量测定经15~35GY五个照射剂量辐照全血在保存期内红细胞CR1分子数目.结果照射后1d,15~25GY剂量组红细胞CR1分子数目相互间比较及分别与对照组比较无明显差异(P>0.05);经30、35GY辐照红细胞CR1分子数目分别与其他剂量组和对照组比较有明显差异(P<0.05~0.01).另外,随着保存期的延长,各剂量组和对照组红细胞CR1分子数目呈阶梯式下降,尤其在照射后3d,30和35GY剂量组红细胞CR1分子数目接近于照射后7d水平,二者相互比较无明显差异(P>0.05).结论在一定范围内(15~25GY)60Co γ射线剂量辐照对红细胞CR1分子数目无明显影响.  相似文献   
29.
We present 36 consecutive patients with intrinsic glioma of the pons. Tumors with exophytic expansion were excluded. There were 16 females and 20 males, ranging in age from 2 to 13 years, median 6 years. The most common presenting symptoms were cranial nerve dysfunction. unsteadiness of gait, and hemiparesis. Computed tomography (CT) showed a hypodense (17/21) or isodense (4/21) expansion of the pons. Five tumors had areas of contrast enhancement. Following information about prognosis and possible types of management, parents decided for or against radiation therapy: twentyfour children underwent irradiation and 12 did not. Median survival among children receiving a full course of irradiation was 280 days, compared to 140 days in an equivalent group of non-irradiated children. Hemiparesis presenting without cranial nerve symptoms and contrast enhancement on CT scan were poor prognostic factors, whereas sex, age, and duration of symptoms at diagnosis were unrelated to prognosis.  相似文献   
30.
多层螺旋CT胸部低剂量扫描对气道三维重建的应用研究   总被引:5,自引:1,他引:4  
目的:比较低剂量与常规剂量条件下中央气道三维重建图像的差别,探讨低剂量螺旋CT扫描进行中央气道三维重建的可行性。材料和方法:32例病例行低剂量(50mAs)平扫及常规剂量(195mAs)平扫(1例)及增强扫描(31例),将两组原始数据分别普通算法及高分辨算法重叠重建出4组横断面图像,并进行气道SSD及VR重建,由两名放射科医师分析4组图像的质量、支气管显示情况、支气管病变检出情况,将结果进行统计学分析。结果:①图像质量:两组剂量间SSD图像质量无明显差异,高分辨重建图像质量≥普通算法重建图像质量;VR图像质量两种剂量之间无明显差异,高分辨算法图像质量≥标准算法重建图像质量。②支气管显示:两名医生评价结果均表明对段以上支气管显示方面无论SSD图像还是VR图像,低剂量与常规剂量组以及两种算法图像之间均无明显差异。③病变检出:无论SSD还是VR图像4组图像对支气管病变的检出无差异。④剂量差别:低剂量扫描比常规剂量扫描辐射剂量大大降低(13.6~3.6mGy)。结论:与常规剂量扫描相比,低剂量薄层扫描气道三维重建图像质量、对中央气道显示及病变检出都无明显差异,而病人接受的辐射剂量却大大降低,因此低剂量薄层扫描气道三维重建可以代替常规剂量重建图像应用于临床气道病变显示。  相似文献   
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