全文获取类型
收费全文 | 19471篇 |
免费 | 1543篇 |
国内免费 | 572篇 |
专业分类
耳鼻咽喉 | 172篇 |
儿科学 | 306篇 |
妇产科学 | 558篇 |
基础医学 | 2528篇 |
口腔科学 | 405篇 |
临床医学 | 2144篇 |
内科学 | 4067篇 |
皮肤病学 | 234篇 |
神经病学 | 1193篇 |
特种医学 | 467篇 |
外国民族医学 | 3篇 |
外科学 | 2638篇 |
综合类 | 1484篇 |
现状与发展 | 3篇 |
一般理论 | 5篇 |
预防医学 | 1080篇 |
眼科学 | 745篇 |
药学 | 1586篇 |
6篇 | |
中国医学 | 574篇 |
肿瘤学 | 1388篇 |
出版年
2024年 | 35篇 |
2023年 | 229篇 |
2022年 | 461篇 |
2021年 | 696篇 |
2020年 | 455篇 |
2019年 | 494篇 |
2018年 | 568篇 |
2017年 | 506篇 |
2016年 | 492篇 |
2015年 | 665篇 |
2014年 | 803篇 |
2013年 | 924篇 |
2012年 | 1389篇 |
2011年 | 1493篇 |
2010年 | 884篇 |
2009年 | 717篇 |
2008年 | 1089篇 |
2007年 | 1095篇 |
2006年 | 1140篇 |
2005年 | 1116篇 |
2004年 | 918篇 |
2003年 | 785篇 |
2002年 | 771篇 |
2001年 | 538篇 |
2000年 | 530篇 |
1999年 | 481篇 |
1998年 | 187篇 |
1997年 | 192篇 |
1996年 | 159篇 |
1995年 | 113篇 |
1994年 | 110篇 |
1993年 | 76篇 |
1992年 | 206篇 |
1991年 | 188篇 |
1990年 | 165篇 |
1989年 | 146篇 |
1988年 | 117篇 |
1987年 | 112篇 |
1986年 | 91篇 |
1985年 | 62篇 |
1984年 | 43篇 |
1983年 | 31篇 |
1982年 | 45篇 |
1981年 | 39篇 |
1980年 | 35篇 |
1979年 | 36篇 |
1978年 | 32篇 |
1977年 | 19篇 |
1975年 | 20篇 |
1973年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Influence of age on the mortality from acute pancreatitis 总被引:6,自引:0,他引:6
The influence of age on the mortality rate of 268 patients with acute pancreatitis was studied. The hospital mortality rate for patients aged below 50 years was 5.9 per cent. The figure increased to 21.3 per cent in patients aged over 75; the high mortality was accounted for by a higher incidence of deaths related to concomitant medical or surgical diseases in the same hospital admission rather than to complications resulting directly from the pathological process of acute pancreatitis. When only deaths due to complications of acute pancreatitis were analysed, the mortality rate was not significantly different between the young and elderly groups. Moreover, the complication rate and the proportion of patients having severe disease (judged by the number of prognostic signs) were not higher in the elderly. Thus acute pancreatitis was intrinsically not more serious were it not for the presence of concomitant diseases with advanced age. 相似文献
13.
This study evaluated the role of insulin, glucagon and the epidermal growth factor (EGF) on liver regeneration after partial hepatectomy. Male Wistar rats, weighing approximately 200 g, were used. A partial hepatectomy, with resection of the medial and left lateral lobes (67.31%), was performed on the control group and seven hormone-treated groups: insulin, glucagon, EGF, insulin plus glucagon, insulin plus EGF, glucagon plus EGF, and a combination of the three hormones. The hormones were administered subcutaneously two days prior to the partial hepatectomy. The groups administered insulin were allowed to drink 20% glucose in water. Another group of rats received simulated operations, i.e., only a laparotomy was performed. The rats were killed at six, 24, 48 and 72 hours after the operation. Remnant liver weight, deoxyribonucleic acid (DNA) content, rate of DNA synthesis, mitotic index, blood glucose and serum insulin levels were measured. The results showed that: 1) the effects of single hormone administration on posthepatectomy liver regeneration were not obvious; 2) combined administration of insulin and glucagon increased the weight of the remnant liver, the DNA content, and the rate of DNA synthesis; 3) the combined administration of insulin, glucagon, and EGF increased the regeneration based on the remnant liver weight and mitotic index; and 4) there was no concordance between the change in blood glucose levels and the effect of hormones during liver regeneration. 相似文献
14.
Toddlers who ingest the drug of abuse 3,4-methylenedioxymethamphetamine (MDMA; 'Ecstasy') are at particularly high risk of serious neurological and cardiovascular side effects. We report of a 20-month-old male toddler who accidentally ingested Ecstasy. He presented with fever and seizures, tachycardia, hypertension, and hyperthermia. Urine amphetamine level was 2111 ng/mL. Treatment included rapid cooling, hydration, and support measures. Vital signs were regularly monitored. His condition became stable on day 2 and urine amphetamine level returned to normal on day 3 of hospitalization. His behavior, activity, and appetite had returned to their usual levels upon follow-up at our outpatient clinic. The incidence of drug abuse with MDMA has increased dramatically over the last decade in developed countries. It can be expected that accidental Ecstasy poisoning in children will increase as well. This case illustrates the need to consider the possibility of accidental Ecstasy ingestion in the differential diagnosis of a child suffering from convulsions with fever. 相似文献
15.
16.
Identifying potential indicators of the quality of end-of-life cancer care from administrative data.
Craig C Earle Elyse R Park Bonnie Lai Jane C Weeks John Z Ayanian Susan Block 《Journal of clinical oncology》2003,21(6):1133-1138
PURPOSE: To explore potential indicators of the quality of end-of-life services for cancer patients that could be monitored using existing administrative data. METHODS: Quality indicators were identified and assessed by literature review for proposed indicators, focus groups with cancer patients and family members to assess candidate indicators and generate new ideas, and an expert panel ranking the meaningfulness and importance of each potential indicator using a modified Delphi approach. RESULTS: There were three major concepts of poor quality of end-of-life cancer care that could be examined using currently-available administrative data (such as Medicare claims): institution of new anticancer therapies or continuation of ongoing treatments very near death; a high number of emergency room visits, inpatient hospital admissions, or intensive care unit days near the end of life; and a high proportion of patients never enrolled in hospice, only admitted in the last few days of life, or dying in an acute-care setting. Concepts such as access to psychosocial and other multidisciplinary services and pain and symptom control are important and may eventually be feasible, but they cannot currently be applied in most data systems. Indicators based on limiting the use of treatments with low probability of benefit or indicators based on economic efficiency were not acceptable to patients, family members, or physicians. CONCLUSION: Several promising claims-based quality indicators were identified that, if found to be valid and reliable within data systems, could be useful in identifying health-care systems in need of improving end-of-life services. 相似文献
17.
Ming-Shian Tsai Wen-Hsi Lin Wen-Ming Hsu Hong-Shiee Lai Po-Huang Lee Wei-Jao Chen 《Journal of gastrointestinal surgery》2008,12(12):2191-2195
Background/aims Surgical resection of choledochal cysts (CC) has become standard treatment. However, surgery is not universally recommended
in early infancy and/or asymptomatic patients. In order to investigate the optimal timing of CC excision, we analyzed clinicopathological
data and surgical results from different age groups.
Material and methods This retrospective review included 107 patients (77 females, 30 males) who underwent CC resection at the National Taiwan University
Hospital between January 1988 and December 2005. Patient demographic, clinical, and surgical data were collected and analyzed.
Results The patients were divided into three groups according to age at the time of surgery: <1 year old (group I, n = 26), 1−16 years old (group II, n = 48), and >16 years old (group III, n = 33). About two thirds of the patients in group I had jaundice, while abdominal pain related to inflammation was the commonest
symptom in groups II and III. Group I suffered significantly fewer surgical complications and less severe liver fibrosis than
groups II or III.
Conclusion CC surgery in infancy and in asymptomatic patients is safe and may prevent the complications of this condition. The results
support a recommendation for early excision. 相似文献
18.
光照疗法对新生儿红细胞谷胱甘肽还原酶活性的影响 总被引:3,自引:0,他引:3
作者对光照疗法(光疗)前及光疗后于口服维生素B_2(43例)和不予口服维生素B_2(17例)的黄疸新生儿的红细胞谷胱甘肽还原酶(GR)的活性进行了动态观察。结果显示,接受短期光疗的黄疸新生儿其红细胞GR活性较光疗前的GR活性有显著下降,光疗后予口服维生素B_2可使下降的红细胞GR活性回升,而不予补充维生素B_2者的红细胞GR活性继续下降。光疗的时间越长,红细胞GR活性的下降越明显,补充维生素B_2使红细胞GR活性回复到正常水平所需的时间也越长。短期光疗也可引起体内维生素B_2的降解,导致红细胞GR活性的下降,为避免因红细胞GR活性下降引起的红细胞额外破坏,对接受光疗的黄疸新生儿常规补充维生素B_2的是必要的。 相似文献
19.
The use of item banks and computerized adaptive testing (CAT) begins with clear definitions of important outcomes, and references those definitions to specific questions gathered into large and well-studied pools, or “banks” of items. Items can be selected from the bank to form customized short scales, or can be administered in a sequence and length determined by a computer programmed for precision and clinical relevance. Although far from perfect, such item banks can form a common definition and understanding of human symptoms and functional problems such as fatigue, pain, depression, mobility, social function, sensory function, and many other health concepts that we can only measure by asking people directly. The support of the National Institutes of Health (NIH), as witnessed by its cooperative agreement with measurement experts through the NIH Roadmap Initiative known as PROMIS (www.nihpromis.org), is a big step in that direction. Our approach to item banking and CAT is practical; as focused on application as it is on science or theory. From a practical perspective, we frequently must decide whether to re-write and retest an item, add more items to fill gaps (often at the ceiling of the measure), re-test a bank after some modifications, or split up a bank into units that are more unidimensional, yet less clinically relevant or complete. These decisions are not easy, and yet they are rarely unforgiving. We encourage people to build practical tools that are capable of producing multiple short form measures and CAT administrations from common banks, and to further our understanding of these banks with various clinical populations and ages, so that with time the scores that emerge from these many activities begin to have not only a common metric and range, but a shared meaning and understanding across users. In this paper, we provide an overview of item banking and CAT, discuss our approach to item banking and its byproducts, describe testing options, discuss an example of CAT for fatigue, and discuss models for long term sustainability of an entity such as PROMIS. Some barriers to success include limitations in the methods themselves, controversies and disagreements across approaches, and end-user reluctance to move away from the familiar. 相似文献
20.
Interleukin-5 has a specific role in various eosinophilic activities. It is the predominant cytokine produces by activated T-lymphocytes isolated from patients with idiopathic hypereosinophilic syndrome. We studied a young patient suffering from idiopathic hypereosinophilic syndrome who presented with Horner's syndrome, peripheral neuropathy and skin ulcers. The IL-5 gene expression by CD4+ T-lymphocytes and the peripheral eosinophil count were raised. The skin ulcers continued to deteriorate despite a swift reduction of the IL-5 gene expression and peripheral eosinophil count following systemic corticosteroid treatment. We suggest that peripheral eosinophilia may not be responsible for the damage in skin lesions and more aggressive treatment may be required. 相似文献