收费全文 | 1411篇 |
免费 | 116篇 |
国内免费 | 10篇 |
耳鼻咽喉 | 12篇 |
儿科学 | 45篇 |
妇产科学 | 57篇 |
基础医学 | 189篇 |
口腔科学 | 9篇 |
临床医学 | 127篇 |
内科学 | 297篇 |
皮肤病学 | 69篇 |
神经病学 | 181篇 |
特种医学 | 73篇 |
外科学 | 125篇 |
综合类 | 4篇 |
一般理论 | 2篇 |
预防医学 | 105篇 |
眼科学 | 7篇 |
药学 | 111篇 |
中国医学 | 2篇 |
肿瘤学 | 122篇 |
2024年 | 1篇 |
2023年 | 19篇 |
2022年 | 45篇 |
2021年 | 74篇 |
2020年 | 48篇 |
2019年 | 57篇 |
2018年 | 55篇 |
2017年 | 36篇 |
2016年 | 50篇 |
2015年 | 72篇 |
2014年 | 56篇 |
2013年 | 84篇 |
2012年 | 115篇 |
2011年 | 128篇 |
2010年 | 69篇 |
2009年 | 64篇 |
2008年 | 91篇 |
2007年 | 92篇 |
2006年 | 82篇 |
2005年 | 67篇 |
2004年 | 58篇 |
2003年 | 47篇 |
2002年 | 53篇 |
2001年 | 6篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 7篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
Purpose
Nuclear cardiology is widely used to diagnose coronary artery disease and to guide patient management, but data on current practices, radiation dose-related best practices, and radiation doses are scarce. To address these issues, the IAEA conducted a worldwide study of nuclear cardiology practice. We present the European subanalysis.Methods
In March 2013, the IAEA invited laboratories across the world to document all SPECT and PET studies performed in one week. The data included age, gender, weight, radiopharmaceuticals, injected activities, camera type, positioning, hardware and software. Radiation effective dose was calculated for each patient. A quality score was defined for each laboratory as the number followed of eight predefined best practices with a bearing on radiation exposure (range of quality score 0 – 8). The participating European countries were assigned to regions (North, East, South, and West). Comparisons were performed between the four European regions and between Europe and the rest-of-the-world (RoW).Results
Data on 2,381 European patients undergoing nuclear cardiology procedures in 102 laboratories in 27 countries were collected. A cardiac SPECT study was performed in 97.9 % of the patients, and a PET study in 2.1 %. The average effective dose of SPECT was 8.0?±?3.4 mSv (RoW 11.4?±?4.3 mSv; P?<?0.001) and of PET was 2.6?±?1.5 mSv (RoW 3.8?±?2.5 mSv; P?<?0.001). The mean effective doses of SPECT and PET differed between European regions (P?<?0.001 and P?=?0.002, respectively). The mean quality score was 6.2?±?1.2, which was higher than the RoW score (5.0?±?1.1; P?<?0.001). Adherence to best practices did not differ significantly among the European regions (range 6 to 6.4; P?=?0.73). Of the best practices, stress-only imaging and weight-adjusted dosing were the least commonly used.Conclusion
In Europe, the mean effective dose from nuclear cardiology is lower and the average quality score is higher than in the RoW. There is regional variation in effective dose in relation to the best practice quality score. A possible reason for the differences between Europe and the RoW could be the safety culture fostered by actions under the Euratom directives and the implementation of diagnostic reference levels. Stress-only imaging and weight-adjusted activity might be targets for optimization of European nuclear cardiology practice.Background
Bisphosphonates are the most widely used treatment for osteoporosis. They accumulate in the bone for years, and therefore, their inhibitory effects on osteoclasts may persist after drug discontinuation. The ideal duration of therapy remains controversial.Questions/Purposes
The purpose of this study is to review the literature to determine the (1) indications for drug holiday, (2) the duration of drug holiday, (3) the evaluation during drug holiday, and (4) the proper treatment and maintenance after drug holiday.Methods
A review of two electronic databases (PubMed/MEDLINE and EMBASE) was conducted using the term “(Drug holiday),” in January 29, 2015. Inclusion criteria were as follows: (1) clinical trials and case control, (2) human studies, (3) published in a peer-review journal, and (4) written in English. Exclusion criteria were as follows: (1) case reports, (2) case series, and (3) in vitro studies.Results
The literature supports a therapeutic pause after 3–5 years of bisphosphonate treatment in patients with minor bone deficiencies and no recent fragility fracture (low risk) and in patients with moderate bone deficiencies and/or recent fragility fracture (moderate risk). In these patients, a bone health reevaluation is recommended every 1–3 years. Patients with high fracture risk should be maintained on bisphosphonate therapy without drug holiday.Conclusion
The duration and length of drug holiday should be individualized for each patient. Evaluation should be based on serial bone mass measurements, bone turnover rates, and fracture history evaluation. If after drug therapy, assessments show an increased risk of fracture, the patient may benefit from initiating another treatment. Raloxifene, teriparatide, or denosumab are available options.Background
Treatment for osteonecrosis of the femoral head (ONFH) remains controversial. Current reviews include low-level evidence studies evaluating the treatment of both pre-collapse and collapse stages of the disease.Questions/Purposes
The purpose of the current study is to systematically review the literature evaluating core decompression (CD) with bone marrow mesenchymal cells (BMMCs), CD alone, and bisphosphonate treatment in pre-collapse ONFH by focusing just on randomized clinical trials (RCTs) reporting functional and radiologic outcomes. We aim to determine if the literature provides evidence supporting any single approach.Methods
Using PubMed and EMBASE databases, we reviewed the clinical evidence of treatments for pre-collapse ONFH following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Twelve RCTs met the inclusion criteria.Results
Results showed that CD with BMMCs has lower risk of femoral head collapse when compared to the CD alone excluding hips lost to follow-up (relative risk (RR) [95% CI]:0.25 [0.11, 0.60]; p?=?0.002) and when assumed that hips lost to follow-up experienced collapse (RR [95% CI]: 0.11 [0.03, 0.47]; p?=?0.003). Neither CD nor bisphosphonate treatments showed lower risk to femoral head collapse when compared to control treatments (p?=?0.46 and 0.31, respectively)Conclusion
Current literature shows that there is a lower risk of femoral head collapse in patients with ONFH treated with CD combined with BMMCs when compared to CD alone; however, there is no robust evidence to determine the effect on functional outcomes. More RCTs assessing new combination therapies and using standardized outcome measures are required.Purpose
The purpose of the present study was to analyze clinicopathologic features and long-term prognosis of gastric stump cancer (GSC) arising in the remnant stomach 5 years or later after partial gastrectomy for benign disease.Methods
We reviewed the results of 176 patients resected with curative intent for GSC at 8 Italian centers belonging to the Italian Research Group for Gastric Cancer (GIRCG). The median (range) follow-up time for surviving patients was 71.2 (6–207) months.Results
One hundred forty-six patients were men, the mean age at the time of diagnosis was 69.2 years, and the great majority (167 cases) underwent Billroth II reconstruction. R0 resection was achieved in 158 (90 %) patients, and in 94 (53 %) lymph node dissection was ≥D2. Postoperative mortality and complication rates were 6.2 and 43.2 %, respectively. T1 tumor was diagnosed in 45 (25 %) cases. Lymph node metastases were evident in 86 patients (49 %). Thirteen patients had involvement of the jejunal mesentery nodes (pJN+); five cases were T2–T3 and eight cases were T4. Overall 5-year survival rate was 53.1 %. Five-year survival rates were 68.1, 37.8, and 33.1 % for pT1, pT2-3, and pT4 tumors, respectively (P = 0.001). Five-year survival rate was 56.5 % for node-negative tumors (pN0), 32.3 % for tumors with nodal metastases without involvement of jejunal mesentery nodes (pN+), and 17.1 % for tumors with involvement of jejunal mesentery nodes (pJN+) (P = 0.002).Conclusions
Our study suggests that an aggressive surgical approach can achieve a satisfactory outcome in GSC. 相似文献Sellar/parasellar tumors (SPTs) very rarely become symptomatic during pregnancy. No specific guidelines exist for their management, that is extremely challenging as mother and fetus health can be jeopardized.
Materials and methodsData of patients with SPTs becoming symptomatic during pregnancy treated at two Italian referral Centers were retrospectively collected. Systematic literature review was also performed.
ResultsOur series consisted of 6 cases, 3 meningiomas, 1 ACTH-secreting adenoma, 1 pituicytoma and 1 craniopharyngioma. Mean age at presentation was 33.6?±?6.0 years. Five patients complained of visual disturbances, associated with headache in one case, that occurred between gestation week (GW) 22 and 34. In 5 cases, pregnancy was uneventful with the delivery of a healthy baby between GW 33 and 35, followed by endoscopic surgical tumor exeresis (n?=?4) or proton bean therapy (n?=?1). Another patient presented with stigmata typical of Cushing’s syndrome and rapidly worsening pre-eclampsia, that required pregnancy interruption and adenomectomy. Based on personal and literature cases, a practical algorithm was proposed to help clinicians dealing with these patients.
ConclusionsSPTs becoming symptomatic in pregnancy deserve careful monitoring and multidisciplinary management. Overall, wait-and-see approach is suggested, reserving surgery to patients with rapidly progressive/life-threatening situations, significant risk of permanent neurological impairment or malignant lesions.
相似文献