全文获取类型
收费全文 | 10247篇 |
免费 | 736篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 293篇 |
妇产科学 | 293篇 |
基础医学 | 1380篇 |
口腔科学 | 233篇 |
临床医学 | 1274篇 |
内科学 | 2036篇 |
皮肤病学 | 259篇 |
神经病学 | 1080篇 |
特种医学 | 184篇 |
外科学 | 893篇 |
综合类 | 64篇 |
一般理论 | 16篇 |
预防医学 | 1306篇 |
眼科学 | 181篇 |
药学 | 682篇 |
中国医学 | 32篇 |
肿瘤学 | 737篇 |
出版年
2024年 | 16篇 |
2023年 | 132篇 |
2022年 | 225篇 |
2021年 | 462篇 |
2020年 | 263篇 |
2019年 | 359篇 |
2018年 | 375篇 |
2017年 | 273篇 |
2016年 | 314篇 |
2015年 | 316篇 |
2014年 | 393篇 |
2013年 | 579篇 |
2012年 | 829篇 |
2011年 | 821篇 |
2010年 | 472篇 |
2009年 | 372篇 |
2008年 | 632篇 |
2007年 | 620篇 |
2006年 | 569篇 |
2005年 | 540篇 |
2004年 | 455篇 |
2003年 | 438篇 |
2002年 | 389篇 |
2001年 | 42篇 |
2000年 | 34篇 |
1999年 | 39篇 |
1998年 | 68篇 |
1997年 | 68篇 |
1996年 | 60篇 |
1995年 | 51篇 |
1994年 | 40篇 |
1993年 | 45篇 |
1992年 | 32篇 |
1991年 | 31篇 |
1990年 | 26篇 |
1989年 | 24篇 |
1988年 | 27篇 |
1987年 | 28篇 |
1986年 | 25篇 |
1985年 | 26篇 |
1984年 | 33篇 |
1983年 | 39篇 |
1982年 | 35篇 |
1981年 | 35篇 |
1980年 | 41篇 |
1979年 | 13篇 |
1978年 | 17篇 |
1977年 | 18篇 |
1975年 | 14篇 |
1973年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Alice T. Sawyer Gabrielle I. Liverant Janie J. Jun Daniel J. Lee Andrew L. Cohen Sunny J. Dutra Diego A. Pizzagalli Denise M. Sloan 《Journal of traumatic stress》2016,29(4):374-378
Learning processes have been implicated in the development and course of posttraumatic stress disorder (PTSD); however, little is currently known about punishment‐based learning in PTSD. The current study investigated impairments in punishment‐based learning in U.S. veterans. We expected that veterans with PTSD would demonstrate greater punishment‐based learning compared to a non‐PTSD control group. We compared a PTSD group with and without co‐occurring depression (n = 27) to a control group (with and without trauma exposure) without PTSD or depression (n = 29). Participants completed a computerized probabilistic punishment‐based learning task. Compared to the non‐PTSD control group, veterans with PTSD showed significantly greater punishment‐based learning. Specifically, there was a significant Block × Group interaction, F(1, 54) = 4.12, p = .047, η2 = .07. Veterans with PTSD demonstrated greater change in response bias for responding toward a less frequently punished stimulus across blocks. The observed hypersensitivity to punishment in individuals with PTSD may contribute to avoidant responses that are not specific to trauma cues. 相似文献
72.
DAA‐based antiviral treatment of patients with chronic hepatitis C in the pre‐ and postkidney transplantation setting 下载免费PDF全文
Sandra Beinhardt Ramona Al Zoairy Peter Ferenci Karin Kozbial Clarissa Freissmuth Rafael Stern Albert Friedrich Stättermayer Rudolf Stauber Michael Strasser Heinz Zoller Bruno Watschinger Alice Schmidt Michael Trauner Harald Hofer Andreas Maieron 《Transplant international》2016,29(9):999-1007
DAA‐based regimens for chronic hepatitis C infection encourage treatment of “difficult‐to‐treat” cohorts. This study investigated efficacy and safety of DAA‐based regimens in HCV patients on dialysis or postkidney or liver/kidney transplantation. Twenty‐five patients treated with DAA combinations were evaluated: 10 were on dialysis (eight: hemodialysis, two: peritoneal dialysis), eight were kidney transplant recipients, and seven were liver/kidney transplant recipients. Except for one patient treated with daclatasvir ([DCV]/60 mg/QD)/simeprevir ([SMV]/150 mg/QD), the others received sofosbuvir‐based regimens ([SOF];400 mg/QD) combined with SMV:eight, DCV:13 or either ledipasvir ([LDV]90 mg/QD), ribavirin ([RBV];weight based) or pegylated interferon/RBV. HCV‐RNA was determined by Abbott RealTime (LLOQ]:12 IU/ml) or Roche AmpliPrep/COBAS TaqMan assay (LLOQ:15 IU/ml); treatment response evaluated every 4 weeks, at the end of treatment, and 4 and 12 weeks thereafter. Twenty‐four (96%) patients achieved SVR 12/24 (ITT‐analysis). Mean treatment duration was 15.1 ± 5.1 weeks (±SD), and two patients terminated prematurely – both reached SVR12. Six patients were hospitalized due to complications of underlying disease. One patient achieved SVR24 but was re‐infected (week 27). Kidney function remained stable; serum creatinine increased in only one patient – SOF was reduced to 400 mg/48 h. Treatment with DAA combinations in renally impaired HCV patients is highly effective and well tolerated. These findings call for further controlled trials and data from real‐life cohorts. 相似文献
73.
Amer K. Karam MD Meier Hsu MS Sujata Patil PhD Michelle Stempel MS Tiffany A. Traina MD Alice Y. Ho MD Hiram S. Cody MD Elisa R. Port MD Monica Morrow MD Mary L. Gemignani MD MPH 《Annals of surgical oncology》2009,16(7):1952-1958
Background Completion axillary lymph node dissection (CALND) is routinely performed in breast cancer patients with positive sentinel
lymph nodes (SLN). We sought to determine the sociodemographic, pathologic, and therapeutic variables that were associated
with CALND.
Methods From 7/1997 to 7/2003, 1,470 patients with invasive breast cancer were SLN positive by intraoperative frozen section or final
pathologic exam by hematoxylin–eosin and/or immunohistochemistry (IHC). A comorbidity score was assigned using Adult Comorbidity
Evaluation-27 system. Fisher’s exact, Wilcoxon tests, and multivariate logistic regression analysis were used.
Results CALND was performed less often in patients with age ≥ 70 years compared with age < 70 years, moderate or severe comorbidities
compared with no or mild, IHC-only positive SLN and breast conservation therapy (BCT compared with mastectomy. Patients who
did not undergo CALND were less likely than CALND patients to have grade III disease, lymphovascular invasion multifocal disease,
tumor size > 2 cm or to receive adjuvant chemotherapy. However, they were more likely to undergo axillary radiotherapy (RT).
On multivariate analysis, age ≥ 70 years [odds ratio (OR) 0.4, 95% confidence interval (CI) 0.26–0.63], IHC-only positive
SLN (OR 0.13, 95%CI 0.09–0.19), presence of moderate to severe comorbidities (OR 0.64, 95%CI 0.41–0.99), tumor size ≤ 2 cm
(OR 0.44, 95%CI 0.29–0.66), axillary RT (OR 0.39, 95%CI 0.20–0.78), and BCT (OR 0.54, 95%CI 0.37–0.79) were all independently
associated with lower odds of CALND.
Conclusions The decision to perform CALND following positive SLN biopsy was multifactorial. Patient factors were a primary determinant
for the use of CALND in our study. The decreased use of CALND in the BCT patients probably reflects reliance on the radiotherapy
tangents to maintain local control in the axilla. 相似文献
74.
Wright H Listinsky J Rim A Chellman-Jeffers M Patrick R Rybicki L Kim J Crowe J 《American journal of surgery》2005,190(4):572-575
BACKGROUND: Screening mammography has led to earlier diagnosis of breast cancer; however, the increased tissue density of young women can complicate mammographic interpretation. We hypothesized that magnetic resonance imaging (MRI) has value in detection of mammographically occult breast cancers, particularly in premenopausal women for whom the sensitivity of mammography is compromised. METHODS: Data were available for 89 women with biopsy-proven breast cancer who had undergone both mammography and breast MRI. Variables evaluated included menopausal status and radiographic findings. Data were analyzed using Fisher's Exact test; P < .05 was considered significant. RESULTS: Of the 89 women in our study, 69 were perimenopausal or postmenopausal and 20 were premenopausal at the time of diagnosis. The malignant lesion was identified on mammography and MRI for a majority of patients. One third of premenopausal women had negative mammography but positive MRI findings. CONCLUSIONS: Our findings support a role for breast MRI in supplementing conventional mammography for early detection of breast cancer in premenopausal women. 相似文献
75.
Giuseppe Filardo Henning Madry Mislav Jelic Alice Roffi Magali Cucchiarini Elizaveta Kon 《Knee surgery, sports traumatology, arthroscopy》2013,21(8):1717-1729
Purpose
The aim of this systematic review is to examine the available clinical evidence in the literature to support mesenchymal stem cell (MSC) treatment strategies in orthopaedics for cartilage defect regeneration.Methods
The research was performed on the PubMed database considering the English literature from 2002 and using the following key words: cartilage, cartilage repair, mesenchymal stem cells, MSCs, bone marrow concentrate (BMC), bone marrow-derived mesenchymal stem cells, bone marrow stromal cells, adipose-derived mesenchymal stem cells, and synovial-derived mesenchymal stem cells.Results
The systematic research showed an increasing number of published studies on this topic over time and identified 72 preclinical papers and 18 clinical trials. Among the 18 clinical trials identified focusing on cartilage regeneration, none were randomized, five were comparative, six were case series, and seven were case reports; two concerned the use of adipose-derived MSCs, five the use of BMC, and 11 the use of bone marrow-derived MSCs, with preliminary interesting findings ranging from focal chondral defects to articular osteoarthritis degeneration.Conclusions
Despite the growing interest in this biological approach for cartilage regeneration, knowledge on this topic is still preliminary, as shown by the prevalence of preclinical studies and the presence of low-quality clinical studies. Many aspects have to be optimized, and randomized controlled trials are needed to support the potential of this biological treatment for cartilage repair and to evaluate advantages and disadvantages with respect to the available treatments.Level of evidence
IV. 相似文献76.
Chylotamponade: an unusual presentation of Gorham's syndrome 总被引:2,自引:0,他引:2
Swelstad MR Frumiento C Garry-McCoy A Agni R Weigel TL 《The Annals of thoracic surgery》2003,75(5):1650-1652
Gorham's Syndrome, also known as massive osteolysis or "vanishing bone disease" results from lymphangiomatosis with adjacent bone resorption. Chylothorax is a common complication in cases of mediastinal involvement. We report a case of Gorham's Syndrome presenting as chylotamponade successfully treated with pericardial drainage, early parenteral nutritional support, bilateral pleurodesis for chylous effusions, and adjuvant external beam radiation. 相似文献
77.
Dixon B. Kaufman George W. Burke III David S. Bruce Christopher P. Johnson A. Osama Gaber David E. R. Sutherland Robert M. Merion Scott A. Gruber Eugene Schweitzer John P. Leone Christopher L. Marsh Edward Alfrey Waldo Concepcion Mark D. Stegall James A. Schulak Paul F. Gores Enrico Benedetti Craig Smith Alice K. Henning Fernando Kuehnel Sarah King William E. Fitzsimmons 《American journal of transplantation》2003,3(7):855-864
A randomized, multicenter, prospective study was conducted at 18 pancreas transplant centers in the United States to determine the role of induction therapy in simultaneous pancreas-kidney (SPK) transplantation. One hundred and 74 recipients were enrolled: 87 recipients each in the induction and noninduction treatment arms. Maintenance immunosuppression consisted of tacrolimus, mycophenolate mofetil, and corticosteroids. There were no statistically significant differences between treatment groups for patient, kidney, and pancreas graft survival at 1-year. The 1-year cumulative incidence of any treated biopsy-confirmed or presumptive rejection episodes (kidney or pancreas) in the induction and noninduction treatment arms was 24.6% and 31.2% (p = 0.28), respectively. The 1-year cumulative incidence of biopsy-confirmed, treated, acute kidney allograft rejection in the induction and noninduction treatment arms was 13.1% and 23.0% (p = 0.08), respectively. Biopsy-confirmed kidney allograft rejection occurred later post-transplant and appeared to be less severe among recipients that received induction therapy. The highest rate of Cytomegalovirus (CMV) viremia/syndrome was observed in the subgroup of recipients who received T-cell depleting antibody induction and received organs from CMV serologically positive donors. Decisions regarding the routine use of induction therapy in SPK transplantation must take into consideration its differential effects on risk of rejection and infection. 相似文献
78.
Khalil SN Maposa D Ghelber O Rabb MF Matuszczak M Ganesan BA Tabrizi HK Chuang AZ 《Middle East journal of anesthesiology》2008,19(4):885-899
BACKGROUND: Children with obstructive sleep apnea (OSA) have a higher rate of adverse post-extubation respiratory events, such as laryngospasm, upper airway obstruction, apnea, desaturation and/or need for re-intubation. They are overly sensitive to sedatives and narcotics. Although the etiology of OSA is primarily obstruction (mechanical or neuromuscular), a central element may contribute to OSA. Caffeine citrate has been shown to be effective in treating apnea of prematurity. This study evaluated whether the administration of caffeine benzoate to children with OSA decreases the number of children who experience adverse post-extubation respiratory events. METHODS: In a randomized, double-blind and placebo-controlled study, children with OSA scheduled for adenotonsillectomy (T&A) received either caffeine benzoate, 20 mg/kg IV, (caffeine group, n = 36) or saline (placebo group, n = 36). The primary outcome evaluated the number of children who developed adverse post-extubation respiratory events, and the secondary outcome was the incidence of those events. RESULTS: The results demonstrated the two groups differed in the number of children who developed adverse post-extubation respiratory events (p = 0.032). The overall incidence of adverse postoperative respiratory events was less in the caffeine group than the placebo group (p = 0.0196). CONCLUSION: In children with OSA scheduled for T&A, administration of caffeine benzoate, 20 mg/kg IV, decreased the number of children who developed adverse post-extubation respiratory events and decreased the overall incidence of adverse post-extubation respiratory events. PACU duration, hospital discharge time and postoperative delirium did not differ between groups. 相似文献
79.
Li Li Alice C Jiang Pin Dong Yi Wan Zi Wei Yu 《Otolaryngology--head and neck surgery》2007,137(4):659-664
OBJECTIVE: To investigate the characteristics of Hep-2 cell with multidrug resistance (MDR) induced by Taxol. STUDY DESIGN: Hep-2 cells were exposed in stepwise escalating concentration of Taxol to develop the resistant cell line-Hep-2T. Cell cycle distribution, apoptosis, and rhodamine accumulation were studied through flow cytometry. The MDR1 and MRP1 genes were detected through real-time quantitative RT-PCR, and the corresponding proteins were detected through Western blotting. RESULTS: The drug resistance of Hep-2T cells to Taxol, doxorubicin, gemcitabine, 5-FU, and cisplatin all increased. The percentage of G0/G1 phase and the antiapoptosis ability increased significantly compared with Hep-2 cells. Both MDR1 and MRP1 also increased at gene and protein level, though MDR1 was more prominent. CONCLUSION: More emphasis should be laid on MDR1/Pgp, the non-Pgp substrate chemotherapeutic agents, and the changes of cell cycle distribution to prevent MDR induced by Taxol. SIGNIFICANCE: These findings may provide theoretical support for the reverse of MDR. 相似文献
80.
Yuan-Mei Liao Molly C. Dougherty Paul P. Biemer Alice R. Boyington Chin-Tai Liao Mary H. Palmer Mary R. Lynn 《International urogynecology journal》2007,18(10):1151-1161
The aim of this study was to estimate the prevalence of lower urinary tract symptoms (LUTS) among female elementary school
teachers in Taipei. A total of 520 self-administered surveys were distributed to 26 elementary schools in Taipei City. Data
analyses were based on 445 usable surveys. The prevalence rates for different types of LUTS ranged from 9.9 to 44.5%. The
prevalence of urinary incontinence (UI; 26.7%) and nocturia (16.0%) fell within the prevalence estimates of these LUTS in
North American and European women. Employed women in this study were more likely to experience LUTS than women in previous
epidemiological or community studies. This study extended research on UI into other LUTS among employed women in Asia. Study
results suggest that the working environment may affect LUTS in female elementary school teachers. This preliminary study
is important for developing future behavioral interventions for female LUTS in the workplace. 相似文献