全文获取类型
收费全文 | 1376篇 |
免费 | 128篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 39篇 |
妇产科学 | 24篇 |
基础医学 | 214篇 |
口腔科学 | 50篇 |
临床医学 | 135篇 |
内科学 | 243篇 |
皮肤病学 | 43篇 |
神经病学 | 54篇 |
特种医学 | 17篇 |
外科学 | 168篇 |
综合类 | 32篇 |
一般理论 | 2篇 |
预防医学 | 63篇 |
眼科学 | 30篇 |
药学 | 118篇 |
中国医学 | 7篇 |
肿瘤学 | 247篇 |
出版年
2023年 | 23篇 |
2022年 | 25篇 |
2021年 | 63篇 |
2020年 | 30篇 |
2019年 | 51篇 |
2018年 | 68篇 |
2017年 | 54篇 |
2016年 | 55篇 |
2015年 | 63篇 |
2014年 | 86篇 |
2013年 | 75篇 |
2012年 | 131篇 |
2011年 | 123篇 |
2010年 | 65篇 |
2009年 | 49篇 |
2008年 | 94篇 |
2007年 | 64篇 |
2006年 | 60篇 |
2005年 | 64篇 |
2004年 | 54篇 |
2003年 | 52篇 |
2002年 | 47篇 |
2001年 | 9篇 |
2000年 | 16篇 |
1999年 | 14篇 |
1998年 | 8篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1983年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 3篇 |
1971年 | 4篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有1505条查询结果,搜索用时 625 毫秒
81.
Though a century old hypothesis, infection as a cause for atherosclerosis is still a debatable issue. Epidemiological and clinical studies had shown a possible association but inhomogeneity in the study population and study methods along with potential confounders have yielded conflicting results. Infection triggers a chronic inflammatory state which along with other mechanisms such as dyslipidemia, hyper-homocysteinemia, hypercoagulability, impaired glucose metabolism and endothelial dysfunction, contribute in pathogenesis of atherosclerosis. Studies have shown a positive relations between Cytotoxic associated gene-A positive strains of Helicobacter pylori and vascular diseases such as coronary artery disease and stroke. Infection mediated genetic modulation is a new emerging theory in this regard. Further large scale studies on infection and atherosclerosis focusing on multiple pathogenetic mechanisms may help in refining our knowledge in this aspect. 相似文献
82.
Hiroko Morisaki Gretchen MacCarrick Mark Lindsay David Liang Sarju G. Mehta Jennifer Hague Judith Verhagen Ingrid van de Laar Marja Wessels Yvonne Detisch Mieke van Haelst Annette Baas Klaske Lichtenbelt Kees Braun Denise van der Linde Jolien Roos‐Hesselink George McGillivray Josephina Meester Isabelle Maystadt Paul Coucke Elie El‐Khoury Sandhya Parkash Birgitte Diness Lotte Risom Ingrid Scurr Yvonne Hilhorst‐Hofstee Takayuki Morisaki Julie Richer Julie Désir Marlies Kempers Andrea L. Rideout Gabrielle Horne Chris Bennett Elisa Rahikkala Geert Vandeweyer Maaike Alaerts Aline Verstraeten Hal Dietz Lut Van Laer Bart Loeys 《Human mutation》2018,39(5):621-634
The Loeys–Dietz syndrome (LDS) is a connective tissue disorder affecting the cardiovascular, skeletal, and ocular system. Most typically, LDS patients present with aortic aneurysms and arterial tortuosity, hypertelorism, and bifid/broad uvula or cleft palate. Initially, mutations in transforming growth factor‐β (TGF‐β) receptors (TGFBR1 and TGFBR2) were described to cause LDS, hereby leading to impaired TGF‐β signaling. More recently, TGF‐β ligands, TGFB2 and TGFB3, as well as intracellular downstream effectors of the TGF‐β pathway, SMAD2 and SMAD3, were shown to be involved in LDS. This emphasizes the role of disturbed TGF‐β signaling in LDS pathogenesis. Since most literature so far has focused on TGFBR1/2, we provide a comprehensive review on the known and some novel TGFB2/3 and SMAD2/3 mutations. For TGFB2 and SMAD3, the clinical manifestations, both of the patients previously described in the literature and our newly reported patients, are summarized in detail. This clearly indicates that LDS concerns a disorder with a broad phenotypical spectrum that is still emerging as more patients will be identified. All mutations described here are present in the corresponding Leiden Open Variant Database. 相似文献
83.
Patrick L. Wagner MD Frances Austin MD Magesh Sathaiah MD Deepa Magge MD Ugwuji Maduekwe MD Lekshmi Ramalingam MD Heather L. Jones MPA-C Matthew P. Holtzman MD Steven A. Ahrendt MD Amer H. Zureikat MD James F. Pingpank MD Herbert J. Zeh III MD David L. Bartlett MD Haroon A. Choudry MD 《Annals of surgical oncology》2013,20(2):506-514
Background
The significance of tumor markers in patients with appendiceal carcinomatosis is poorly defined. We determined preoperative and postoperative tumor marker levels in patients undergoing cytoreductive surgery (CRS) and heated intraperitoneal chemoperfusion (HIPEC) and examined their association with clinicopathologic features and survival.Methods
A total of 176 patients undergoing attempted CRS/HIPEC for appendiceal carcinomatosis had at least 1 tumor marker measured. Marker levels were correlated with tumor characteristics and oncologic outcomes. Kaplan–Meier curves and multivariate Cox regression models were used to identify prognostic factors affecting progression and survival.Results
At least 1 marker was elevated prior to CRS/HIPEC in 70 % of patients (CEA, 54.1 %; CA19-9, 47.7 %; CA-125, 47.2 %). Among patients with elevated preoperative marker levels, normalization occurred postoperatively in 79.4 % for CEA, 92.3 % for CA19-9, and 60 % for CA-125. Absolute preoperative tumor marker levels correlated with peritoneal carcinomatosis index (PCI) (p < .0002), and the number of elevated markers was associated with PCI and progression-free survival (PFS). Elevated postoperative CEA level was associated with decreased PFS (median, 13 vs 36 months, p = .0008). On multivariate Cox regression analysis, elevated preoperative CA19-9 was associated with shorter PFS (hazard ratio [HR] 2.9, 95 % confidence interval [95 % CI] 1.5–5.3, p = .0008), whereas elevated CA-125 was associated with shorter overall survival (HR 2.6, 95 % CI 1.3–5.4, p = .01).Conclusions
Most patients with appendiceal carcinomatosis will have at least 1 elevated tumor marker and will normalize following CRS/HIPEC, allowing for ongoing surveillance. CA19-9 is a promising biomarker for early progression following CRS/HIPEC, whereas CA-125 is associated with shorter survival. 相似文献84.
Ivana T. Croghan PhD Sandhya Pruthi MD J. Taylor Hays MD Stephen Cha MS Ruth E. Johnson MD Marianne Kosel AA Richard Morris BA Richard D. Hurt MD 《The breast journal》2009,15(5):489-495
Abstract: The purpose of this study was to assess the predictive value of smoking history on breast cancer diagnosis in a referral clinic population. We conducted a case–control study using clinical data collected on 8,097 female patients (1,225 breast cancer cases and 6,872 controls) seen in the Mayo Clinic Breast Clinic between August 1, 1993 and November 31, 2003. Breast cancer patients and noncancer patients significantly differed with respect to age at time of the index visit (p < 0.001), number of pregnancies (p = 0.006), number of live births (p = 0.002), vital status at last known follow-up (p < 0.001), current menstruation (p < 0.001), age at menopause (p < 0.001), history of hysterectomy (p < 0.001), use of oral contraception (p = 0.05), duration of oral contraception use (p = 0.001), use of other exogenous hormones (p < 0.001), duration of exogenous hormone use (p = 0.05), breast pain at time of index visit (p = 0.002), smoking status (p < 0.001), and use of five or more alcoholic beverages per week (p = 0.002). After adjustment for these baseline characteristics, having a personal history of smoking was found to be predictive of breast cancer diagnosis (odds ratios [OR] = 1.25, p = 0.004). Other positive predictors for breast cancer diagnosis were: age (OR = 1.02, p < 0.001), history of hysterectomy (OR = 0.66, p < 0.001), prior use of oral contraception for more than 11 years (OR = 2.10, p < 0.001), and prior use of other exogenous hormones/estrogen (OR = 1.81, p < 0.001). In this referral practice having a personal history of smoking is predictive of breast cancer diagnosis. Further studies are needed to further explore this relationship. 相似文献
85.
Background Bisphosphonate use in adult patients has been linked to osteonecrosis of the jaw (ONJ). This complication has not been systematically assessed in a paediatric population receiving bisphosphonates.
Objective To assess our cohort of paediatric patients treated with intravenous bisphosphonate for occurrence of ONJ.
Design Observational study at a tertiary children's hospital.
Patients A total of 42 paediatric patients with osteoporosis who received bisphosphonate infusions for a mean of 6·5 years (SD 2·7 years) were assessed clinically and radiographically for possible ONJ. Among 42, 37 patients had received disodium pamidronate 1 mg/kg/dose at a mean cumulative dose of 19·8 mg/kg and zoledronic acid (ZA) 0·05 mg/kg/dose at a mean cumulative dose of 0·49 mg/kg; four had received ZA and one received pamidronate alone. Invasive dental treatment during bisphosphonate treatment, a known risk factor for osteonecrosis, was specifically assessed.
Results In all patients assessed, including 11 who had invasive dental treatment, there were no cases of osteonecrosis.
Conclusion ONJ has so far not been demonstrated in this patient group. 相似文献
Objective To assess our cohort of paediatric patients treated with intravenous bisphosphonate for occurrence of ONJ.
Design Observational study at a tertiary children's hospital.
Patients A total of 42 paediatric patients with osteoporosis who received bisphosphonate infusions for a mean of 6·5 years (SD 2·7 years) were assessed clinically and radiographically for possible ONJ. Among 42, 37 patients had received disodium pamidronate 1 mg/kg/dose at a mean cumulative dose of 19·8 mg/kg and zoledronic acid (ZA) 0·05 mg/kg/dose at a mean cumulative dose of 0·49 mg/kg; four had received ZA and one received pamidronate alone. Invasive dental treatment during bisphosphonate treatment, a known risk factor for osteonecrosis, was specifically assessed.
Results In all patients assessed, including 11 who had invasive dental treatment, there were no cases of osteonecrosis.
Conclusion ONJ has so far not been demonstrated in this patient group. 相似文献
86.
87.
88.
The incidence of systemic fungal infections that has risen dramatically over the past three decades has propelled a continuous need for more potent antifungal drugs. The purpose of this research was to evaluate the chemotherapeutic activity of a new heptaene polyene macrolide antibiotic (SJA-95) and liposomal incorporated SJA-95 (lip. SJA-95) in a mouse model of aspergillosis and cryptococcosis respectively. Lip. SJA-95 was prepared in our laboratory by the proliposome method involving incorporation of the antifungal into the proliposome mixture and its subsequent conversion into a liposomal dispersion by a simple dilution step. Treatment with free SJA-95 and lip. SJA-95, both in aspergillosis and cryptococcosis, progressively prolonged the survival time and decreased the fungal loads in vital organs respectively. A higher LD50 value of lip. SJA as compared to that of free SJA-95 was indicative of reduced toxicity of lip. SJA-95. Our findings suggest lip. SJA-95 treatment results in prolonged survival time, effective microbiological clearance and reduced toxicity that might help to establish its usefulness as a chemotherapeutic agent in systemic fungal infections with fewer adverse reactions. 相似文献
89.
90.
Lauren A. Wirtzfeld PhD Goutam Ghoshal PhD Zachary T. Hafez MS Kibo Nam MS Yassin Labyed MS Janelle J. Anderson MS Maria-Teresa Herd PhD Alexander Haak MS Zhi He MS Rita J. Miller DVM Sandhya Sarwate MD Douglas G. Simpson PhD James A. Zagzebski PhD Timothy A. Bigelow PhD Michael L. Oelze PhD Timothy J. Hall PhD William D. O'Brien Jr PhD 《Journal of ultrasound in medicine》2010,29(7):1117-1123
Objective. To translate quantitative ultrasound (QUS) from the laboratory into the clinic, it is necessary to demonstrate that the measurements are platform independent. Because the backscatter coefficient (BSC) is the fundamental estimate from which additional QUS estimates are calculated, agreement between BSC results using different systems must be demonstrated. This study was an intercomparison of BSCs from in vivo spontaneous rat mammary tumors acquired by different groups using 3 clinical array systems and a single‐element laboratory scanner system. Methods. Radio frequency data spanning the 1‐ to 14‐MHz frequency range were acquired in 3 dimensions from all animals using each system. Each group processed their radio frequency data independently, and the resulting BSCs were compared. The rat tumors were diagnosed as either carcinoma or fibroadenoma. Results. Carcinoma BSC results exhibited small variations between the multiple slices acquired with each transducer, with similar slopes of BSC versus frequency for all systems. Somewhat larger variations were observed in fibroadenomas, although BSC variations between slices of the same tumor were of comparable magnitude to variations between transducers and systems. The root mean squared (RMS) errors between different transducers and imaging platforms were highly variable. The lowest RMS errors were observed for the fibroadenomas between 4 and 5 MHz, with an average RMS error of 4 × 10?5 cm?1Sr?1 and an average BSC value of 7.1 × 10?4 cm?1Sr?1, or approximately 5% error. The highest errors were observed for the carcinoma between 7 and 8 MHz, with an RMS error of 1.1 × 10?1 cm?1Sr?1 and an average BSC value of 3.5 × 10?2 cm?1Sr?1, or approximately 300% error. Conclusions. This technical advance shows the potential for QUS technology to function with different imaging platforms. 相似文献