全文获取类型
收费全文 | 1814篇 |
免费 | 125篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 54篇 |
妇产科学 | 56篇 |
基础医学 | 208篇 |
口腔科学 | 31篇 |
临床医学 | 230篇 |
内科学 | 330篇 |
皮肤病学 | 26篇 |
神经病学 | 188篇 |
特种医学 | 81篇 |
外科学 | 247篇 |
综合类 | 37篇 |
一般理论 | 3篇 |
预防医学 | 207篇 |
眼科学 | 53篇 |
药学 | 110篇 |
中国医学 | 3篇 |
肿瘤学 | 66篇 |
出版年
2021年 | 21篇 |
2019年 | 15篇 |
2018年 | 29篇 |
2017年 | 17篇 |
2016年 | 20篇 |
2015年 | 27篇 |
2014年 | 45篇 |
2013年 | 50篇 |
2012年 | 59篇 |
2011年 | 70篇 |
2010年 | 25篇 |
2009年 | 56篇 |
2008年 | 79篇 |
2007年 | 93篇 |
2006年 | 78篇 |
2005年 | 78篇 |
2004年 | 70篇 |
2003年 | 57篇 |
2002年 | 59篇 |
2001年 | 61篇 |
2000年 | 54篇 |
1999年 | 46篇 |
1998年 | 31篇 |
1997年 | 20篇 |
1996年 | 28篇 |
1995年 | 15篇 |
1994年 | 21篇 |
1993年 | 17篇 |
1992年 | 46篇 |
1991年 | 40篇 |
1990年 | 41篇 |
1989年 | 31篇 |
1988年 | 34篇 |
1987年 | 48篇 |
1986年 | 41篇 |
1985年 | 36篇 |
1984年 | 28篇 |
1983年 | 20篇 |
1982年 | 25篇 |
1979年 | 27篇 |
1978年 | 23篇 |
1977年 | 12篇 |
1974年 | 17篇 |
1973年 | 13篇 |
1971年 | 10篇 |
1970年 | 17篇 |
1969年 | 15篇 |
1968年 | 17篇 |
1967年 | 18篇 |
1966年 | 16篇 |
排序方式: 共有1943条查询结果,搜索用时 15 毫秒
981.
Mary Lee Barron 《The Journal for Nurse Practitioners》2013,9(3):161-165
The Centers for Disease Control and Prevention published recommendations to improve health and health care for women before and between pregnancies. However, reproductive health is also sensitive to behaviors and conditions that are associated with chronic disease later in life. Fertility literacy, as a part of health literacy, is important for improving reproductive health, pregnancy outcomes, and chronic disease prevention. The key elements to educating women about modifiable risk factors and their effects on fertility are outlined. These topics are easily addressed as a part of health promotion at a primary care visit. 相似文献
982.
Monica Da Silva MD Jessica Porembka MD Ali A. Mokdad MD MS Stephen Seiler MD James Huth MD Aeisha Rivers MD Rachel Wooldridge MD Amanda Chu MD Emily Brown MD Jean Bao MD Deborah Farr MD Meghan Hansen MD Alison Unzeitig‐Barron MD Marilyn Leitch MD Roshni Rao MD 《The breast journal》2018,24(2):161-166
Multiple localizers placed in a bracketed fashion facilitates excision of radiographically extensive breast lesions. In this study, bracketed radioactive seed localization (bRSL) was compared to bracketed wire localization (bWL). We hypothesized that bRSL would achieve adequate margins and decrease re‐operation rates with similar or less specimen volumes (SV) than bWL. Retrospective review identified patients who underwent bracketed breast procedures at an academic medical center. Data collected included patient demographics, tumor features, treatment variables, and surgical outcomes. Wilcoxon rank‐sum test and chi‐square test were used to compare continuous and categorical data, respectively. A multivariable logistic regression model was used to evaluate the association between re‐excision and localization technique after adjusting for clinically relevant variables. Patients who underwent bWL were 3.9 times more likely to undergo re‐excision compared to patients in bRSL group (OR=3.9, 95% CI: 2.0‐7.4). Initial and total SV did not significantly differ between the two groups (P=.4). Patients were significantly more likely to undergo a mastectomy in the bWL group than in the bRSL group (24% vs 7%; P<.01). For patients undergoing excision of radiologically extensive breast lesions, bRSL serves as an alternative to bWL. In this retrospective study, bRSL was associated with a decreased re‐excision rate with similar SV and a lower rate of mastectomy when compared to bWL. 相似文献
983.
984.
Massimo Griselli Simon P. McGuirk Victor Ofoe Oliver Stümper John G.C. Wright Joseph V. de Giovanni David J. Barron William J. Brawn 《European journal of cardio-thoracic surgery》2006,30(6):930-935
Objective: This study evaluated the requirement for surgical reoperation and catheter-based reintervention to central pulmonary arteries (CPAs) following Norwood Procedure (NP). We sought to identify the influence of various surgical techniques employed during NP on subsequent interventions. Methods: Between 1993 and 2004, 226 patients underwent Stage II following NP. Ninety-eight patients (43%) had completion of Fontan circulation (Stage III) and a further 107 (47%) are on course for Fontan completion with 21 (9%) inter-stage deaths. During NP, the aortic arch was reconstructed without additional material (n = 91, 40%) or with a pulmonary homograft patch (n = 135, 60%). Pulmonary blood flow was supplied by modified Blalock–Taussig shunt (n = 177, 78%) or right ventricle to pulmonary artery conduit (RV-PA; n = 49, 22%). The CPAs defect was closed directly (n = 69, 31%) or with a patch (n = 157, 69%). Complete resection of coarctation was performed in 126 patients (56%). Results: Ninety-seven patients (43%) required surgical reoperation to CPAs during Stage II. Actuarial freedom from reoperation was 60 ± 3%, 52 ± 4% and 50 ± 4% at 1, 5 and 10 years, respectively. On multivariable analysis, NP with RV-PA increased risk of reoperation (LR 8.3, 5.3–13.2; p < 0.001). Forty-one patients (18%) required catheter-based reintervention on CPAs. Actuarial freedom from reintervention was 98 ± 1%, 72 ± 4% and 58 ± 6% at 1, 5 and 10 years, respectively. CPA problems were almost exclusively limited to the proximal Left pulmonary artery. On multivariable analysis, catheter-based reintervention became more common with time. Complete resection of coarctation increased risk of reintervention (LR 3.9, 1.6–9.6; p < 0.005). Arch reconstruction and CPAs repair techniques did not affect risk of reoperation or reintervention on CPAs. Conclusions: CPA stenoses and hypoplasia need surgical attention in approximately half of all patients undergoing the NP. The need for reoperation is increased when using the RV-PA conduit technique (although the majority of these are performed as part of the Stage II procedure). Catheter reinterventions are almost exclusively confined to the left CPA and are increased when the arch is shortened by resection of the coarctation tissue at time of NP. 相似文献
985.
D. H. Solomon E. M. Brown D. Chandler A. Bower R. Barron H. Mogun J. M. Franklin 《Osteoporosis international》2014,25(9):2255-2262
Summary
Among 125,954 new users of osteoporosis (OP) medications, 77 % of subjects stopped OP medications, and 23 % of subjects added or started a new OP medication during follow-up, with the first addition or start of a new OP medication occurring in a mean of 739 days after original OP treatment.Introduction
We described patterns and predictors of OP medication use, focusing on treatment changes over time.Methods
We analyzed health and pharmacy insurance claims for a large cohort of low-income Medicare beneficiaries with a drug benefit for the years 1998–2008. Study subjects had documented Medicare claims and no receipt of OP medications (i.e., bisphosphonate, raloxifene, calcitonin, teriparatide, or hormonal therapy) during a baseline of 180 days. Subjects were then required to start an OP medication. Baseline patient and prescriber characteristics were assessed in multivariable Cox regression models to identify correlates of adding or starting a new OP medication. Fractures, bone mineral density testing, and visits with endocrinologists or rheumatologists occurring after baseline were also examined as correlates.Results
We included 125,954 new users of OP medications with a mean age of 78 years, 97 % female, and 92 % white. OP medication prescribers included specialists (i.e., endocrinologists or rheumatologists) (6.2 %), orthopedic surgeons (1.0 %), primary care providers (64.9 %), other physicians (3.7 %), and missing (24.1 %). Seventy-seven percent of subjects stopped OP medications, and 23 % of subjects added or started a new OP medication during follow-up, with the first addition or start of a new OP medication occurring in a mean of 739 days after original OP treatment; 4 % added or started a new OP medication more than once. In fully adjusted models, many baseline variables correlated with starting a second OP medication. Post-baseline fractures [hazard ratio (HR) 1.76, 95 % confidence interval (CI) 1.71–1.82] and bone mineral density testing (HR 2.94, 95 % CI 2.86–3.03) were strong predictors.Conclusion
Approximately one quarter of patients starting an OP medication added or started a new OP medication during follow-up. Long-term sequential treatment strategy trials would inform optimal medication treatment for OP. 相似文献986.
987.
Daniel C. Trottier Philip Barron Vijay Moonje Shaheer Tadros 《Canadian journal of surgery》2009,52(3):182-186
Background
Outpatient surgery benefits patients and surgeons alike, as it is convenient, safe and cost-effective. We sought to assess the safety and feasibility of outpatient thyroid surgery (OTS) at an ambulatory site affiliated with a teaching hospital.Methods
We performed a retrospective chart review of patients who underwent hemithyroidectomy, subtotal thyroidectomy, total thyroidectomy or completion thyroidectomy between 2002 and 2004 at the Riverside campus of The Ottawa Hospital. We analyzed patient outcomes based on hospital admission and readmission rates as well as complication rates.Results
Two hundred and thirty-two patients met our inclusion criteria. Most patients were women (84%) with a mean age of 47 years. Of these patients, 43 had total thyroidectomies, 75 had subtotal thyroidectomies, 42 had left hemithyroidectomies, 57 had right hemithyroidectomies and 18 had completion thyroidectomies; 26% of these procedures were performed to treat cancer. Other pathologies included multinodular goitre (37%), adenoma (21%), nodular hyperplasia (12%) and Hashimoto thyroiditis (4%). The mean duration of surgery was 87 (range 50–150) minutes. No patients died or underwent reoperation. Complications included hypocalcaemia in 6 patients, hematoma in 1 patient, vocal cord injury in 1 patient and wound infection in 2 patients. All patients but 1 were discharged within 10 hours of surgery; the hospital admission rate was 0.4%. Four patients were readmitted within 1 week of surgery (2 for hypocalcemia, 1 for wound infection and 1 for pain control).Conclusion
Outpatient thyroid surgery is safe and is associated with a low complication rate. 相似文献988.
Mullani N Herbst R Abbruzzese J Charnsangavej C Kim E Tran H Barron B Lamki L Gould K 《Clinical positron imaging : official journal of the Institute for Clinical P.E.T》2000,3(4):151
Endostatin is a novel antiangiogenic agent currently in phase I trials. In the context of this trial, we are evaluating the use of non-invasive imaging with PET to determine the relationship between tumor blood flow and glucose metabolism in imaged tumors from treated patients.Ten patients have been treated with escalating daily iv Endostatin doses of 30 to 180 mg/m(2). PET images were obtained before the start of therapy and again after 28 days of treatment. Each patient was scanned with Oxygen-15 labeled water for estimation of tumor blood flow and Flourine-18 labeled FDG to estimate tumor metabolic activity. In most cases, two distinct tumor-bearing sites were analyzed in each patient. Thus, a total of 19 tumors were imaged. Regional blood flow and standard uptake values (SUV) were computed at baseline and 28 days post treatment and the percentage change in blood flow and SUV plotted as a function of Endostatin dose.Both blood flow and glucose metabolism in the imaged tumors were observed to increase in patients treated with =60 mg/m(2)/d, but became uncoupled in the tumors imaged from patients treated at the 180 mg/m(2)/d dose level. Thus, in patients receiving Endostatin at a dose of 180 mg/m(2)/d, blood flow decreased but glucose metabolism increased. This relationship is displayed in Figure 1 below. 相似文献
989.
Controversy persists over the efficacy of intercostal nerve block administered through a tunnelled extrapleural catheter. We have undertaken a randomized, prospective double-blind trial of two different local anaesthetic regimes to evaluate the effect of this technique on post-thoracotomy pain relief and pulmonary function. Sixty-eight patients were randomized to receive bupivacaine 0.25% (n = 22), lignocaine 1% (n = 21) or 0.9% NaCl (saline) (n = 20) via an extrapleural catheter, inserted peroperatively. All patients underwent a standard posterolateral thoracotomy. Pain was assessed using a visual analogue pain score and by the requirement for opiate analgesia. Pulmonary function was measured using bedside spirometry. Pain scores were lower in the local anaesthetic groups at 24, 32 and 72 h compared with placebo (P < 0.05) and the total amount of opiate required was less than placebo for both lignocaine and bupivicaine (P < 0.05). Pulmonary function was better in the local anaesthetic groups throughout the post-operative period and was most pronounced at 24 h with a mean improvement of 30% for forced expiratory volume (FEV1), 24% for forced vital capacity (FVC) and 19% for peak expiratory flow rate (PEFR) compared with placebo. There was no significant difference between pain scores, opiate requirement or pulmonary function between lignocaine and bupivicaine. CT scanning demonstrated containment of the local anaesthetic in an extra-pleural tunnel. Extra-pleural infusion of local anaesthetics is a simple technique, with low risk of complications and provides effective pain relief as well as an improvement in post-operative pulmonary function. Lignocaine is equally as effective as bupivacaine and its use would result in some cost-saving. 相似文献
990.
Goetz DD Bremner BR Callaghan JJ Capello WN Johnston RC 《The Journal of bone and joint surgery. American volume》2004,(11):2419-2423
We previously reported the results at a mean of five years following the use of a tripolar constrained acetabular component to treat recurrently dislocating total hip prostheses. In this study, we report the results after longer follow-up, with emphasis on the prevalence of implant loosening, osteolysis, and later recurrent instability. Fifty-five patients treated with a total of fifty-six constrained acetabular components because of recurrent dislocations of a total hip prosthesis (average, six dislocations; range, two to twenty dislocations) were followed for an average of 10.2 years (range, 7.0 to 13.2 years) or until death. Four (7%) of the fifty-six hips had a subsequent dislocation or failure of the device. Three femoral components (5%) and two acetabular components (4%) were revised because of aseptic loosening. One hip was revised because of osteolysis. We concluded that this constrained acetabular component provides durable protection against additional dislocations without substantial deleterious effects on component fixation. We use this device to treat recurrent dislocation when other modalities are unlikely to be effective. 相似文献