收费全文 | 5859篇 |
免费 | 242篇 |
国内免费 | 27篇 |
耳鼻咽喉 | 133篇 |
儿科学 | 231篇 |
妇产科学 | 260篇 |
基础医学 | 789篇 |
口腔科学 | 64篇 |
临床医学 | 433篇 |
内科学 | 1457篇 |
皮肤病学 | 75篇 |
神经病学 | 490篇 |
特种医学 | 75篇 |
外科学 | 392篇 |
综合类 | 37篇 |
一般理论 | 1篇 |
预防医学 | 468篇 |
眼科学 | 184篇 |
药学 | 631篇 |
中国医学 | 11篇 |
肿瘤学 | 397篇 |
2024年 | 7篇 |
2023年 | 46篇 |
2022年 | 154篇 |
2021年 | 240篇 |
2020年 | 94篇 |
2019年 | 120篇 |
2018年 | 141篇 |
2017年 | 136篇 |
2016年 | 157篇 |
2015年 | 155篇 |
2014年 | 219篇 |
2013年 | 267篇 |
2012年 | 435篇 |
2011年 | 478篇 |
2010年 | 256篇 |
2009年 | 203篇 |
2008年 | 339篇 |
2007年 | 425篇 |
2006年 | 400篇 |
2005年 | 391篇 |
2004年 | 400篇 |
2003年 | 368篇 |
2002年 | 329篇 |
2001年 | 23篇 |
2000年 | 19篇 |
1999年 | 24篇 |
1998年 | 32篇 |
1997年 | 31篇 |
1996年 | 20篇 |
1995年 | 25篇 |
1994年 | 10篇 |
1993年 | 8篇 |
1992年 | 13篇 |
1991年 | 11篇 |
1990年 | 6篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 8篇 |
1984年 | 11篇 |
1983年 | 12篇 |
1982年 | 12篇 |
1981年 | 11篇 |
1980年 | 7篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1975年 | 9篇 |
1974年 | 8篇 |
1972年 | 4篇 |
Objective
The need for public health laboratories (PHLs) to prioritize resources has led to increased interest in sharing diagnostic services. To address this concept for tuberculosis (TB) testing, the New York State Department of Health Wadsworth Center and the Rhode Island State Health Laboratories assessed the feasibility of shared services for the detection and characterization of Mycobacterium tuberculosis complex (MTBC).Methods
We assessed multiple aspects of shared services including shipping, testing, reporting, and cost. Rhode Island State Health Laboratories shipped MTBC-positive specimens and isolates to Wadsworth Center. Average turnaround times were calculated and cost analysis was performed.Results
Testing turnaround times were similar at both PHLs; however, the availability of conventional drug susceptibility testing (DST) results for Rhode Island primary specimens and isolates were extended by approximately four days of shipping time. An extended molecular testing panel was performed on every specimen submitted from Rhode Island State Health Laboratories to Wadsworth Center, and the total cost per specimen at Wadsworth Center was $177.12 less than at Rhode Island State Health Laboratories, plus shipping. Following a mid-study review, Wadsworth Center provided testing turnaround times for detection (same day), species determination of MTBC (same day), and molecular DST (2.5 days).Conclusion
The collaboration between Wadsworth Center and Rhode Island State Health Laboratories to assess shared services of TB testing highlighted a successful model that may serve as a guideline for other PHLs. The provision of additional rapid testing at a lower cost demonstrated in this study could potentially improve patient management and result in significant cost and resource savings if used in similar models across the country.Public health laboratories (PHLs) are essential for disease prevention and control. They serve as a first line of defense by rapidly recognizing and averting the spread of communicable diseases. In addition, they play a critical role in providing specialized tests for low-incidence, high-risk diseases, such as tuberculosis (TB), rabies, and botulism.1 Due to recent economic constraints, many PHLs have suffered financial pressures, including budget and staffing cuts. In some cases, PHLs have reduced or eliminated certain tests, creating a potential risk to the public''s health. As an alternative to the discontinuation of services, one suggested approach was the investigation of shared services with other PHLs in different jurisdictions through testing directories and pilot projects with assistance and support from the Centers for Disease Control and Prevention (CDC) and the Association of Public Health Laboratories (APHL).2,3TB, which is caused by the bacteria Mycobacterium tuberculosis, is a disease for which PHLs play an important role by providing diagnostics that contribute to prevention. Despite an overall decline in cases, TB continues to be a significant burden on social, public health, and economic systems in the United States.4 Maintaining a comprehensive and efficient laboratory system is critical to the continued decline of TB rates and overall prevention and control of TB in the United States. However, providing comprehensive TB testing services is becoming increasingly expensive per case identified. Additionally, retaining technical proficiency remains a challenge, especially as many experienced personnel are lost to retirement and are difficult to replace.5In 2013, a total of 9,582 new TB cases were reported in the United States, with an incidence rate of 3.0 cases per 100,000 population. Only four states reported more than 500 cases of TB: California, Texas, New York, and Florida, accounting for half of all TB cases in the United States. The TB incidence rate in New York State (NYS) is 4.4 per 100,000 population.4 The overall number of TB cases in NYS has decreased slightly over time, while the number of drug-resistant TB (DR TB) cases has remained steady during the past five years. Additionally, the percentage of multidrug-resistant TB (MDR TB) cases in NYS has increased from 1.3% to 3.6% during the past five years.6 In contrast, the TB incidence rate in Rhode Island is 2.6 per 100,000 population, and the overall number of TB cases has remained constant; DR TB and MDR TB cases in Rhode Island are rare.4,7 Given the low number of TB-positive specimens received each year in Rhode Island State Health Laboratories, developing an extensive, increasingly molecular-based, testing program for TB may not be cost effective. In contrast, a high proportion of specimens received each year by the NYS Department of Health Wadsworth Center are Mycobacterium tuberculosis complex (MTBC) positive, including DR TB and MDR TB cases, and an extensive testing program has been implemented.We assessed the feasibility of shared services for the detection and characterization of MTBC between Wadsworth Center and Rhode Island State Health Laboratories during a 10-month time period. Multiple aspects critical to the implementation of shared services were examined, including shipping, testing, reporting, and cost. During this project, Wadsworth Center provided services to Rhode Island State Health Laboratories for rapid detection of MTBC, MTBC species identification, rapid detection of mutations associated with rifampin and isoniazid resistance, and conventional drug susceptibility testing (DST). Importantly, this partnership allowed Wadsworth Center to assess its ability to share its extended testing capabilities with another PHL, determine if the additional services provided were beneficial to patient treatment and outcomes, and identify any potential issues with this testing approach. 相似文献The aim of the study was to assess the effectiveness of Superb Micro-vascular Imaging (SMI) as an alternative to Contrast-Enhanced Ultrasound (CEUS) and Computed Tomography Angiography (CTA) for endoleak detection and classification in patients followed up after endovascular abdominal aortic aneurysm repair (EVAR).
Materials and methodsFrom May 2015 to January 2017, 30 patients underwent post-EVAR follow-up with Color Doppler Ultrasound (CDUS), CEUS, SMI, and CTA examinations. Aneurysmal sac diameter and graft patency were evaluated; endoleaks were identified and classified. Sensitivity, specificity, and accuracy values were calculated for each of the four diagnostic methods of endoleak detection. A percentage of agreement and Cohen’s Kappa coefficient were calculated for comparison of methods in terms of endoleak identification.
ResultsCTA revealed fifteen endoleaks (50%): three type Ia, nine type II, and three type III. The sensitivity of CDUS, CEUS, and SMI relative to CTA was 27%, 100%, and 100%, respectively. Specificity was 93%, 93%, and 93%, respectively. Accuracy was 60%, 97%, and 97%, respectively. There were no differences between SMI and CEUS in terms of sensitivity, specificity, or accuracy (100%, 93%, and 97%). We do not observe statistically significant differences between CTA, CEUS, and SMI concerning endoleak identification ability. The weakest method in endoleak identification was CDUS.
ConclusionsThe analysis showed that SMI is effective, repeatable, and comparable with the CEUS modality in identification endoleaks after EVAR; it may be considered as a potential tool to monitor patients after EVAR implantation, especially those with renal insufficiency or with an allergy to any contrast media.
相似文献