全文获取类型
收费全文 | 22455篇 |
免费 | 1501篇 |
国内免费 | 256篇 |
专业分类
耳鼻咽喉 | 379篇 |
儿科学 | 322篇 |
妇产科学 | 298篇 |
基础医学 | 3846篇 |
口腔科学 | 395篇 |
临床医学 | 1887篇 |
内科学 | 4395篇 |
皮肤病学 | 741篇 |
神经病学 | 1934篇 |
特种医学 | 1188篇 |
外科学 | 3056篇 |
综合类 | 89篇 |
一般理论 | 4篇 |
预防医学 | 831篇 |
眼科学 | 490篇 |
药学 | 2137篇 |
中国医学 | 296篇 |
肿瘤学 | 1924篇 |
出版年
2023年 | 142篇 |
2022年 | 296篇 |
2021年 | 826篇 |
2020年 | 423篇 |
2019年 | 593篇 |
2018年 | 688篇 |
2017年 | 523篇 |
2016年 | 791篇 |
2015年 | 1009篇 |
2014年 | 1153篇 |
2013年 | 1369篇 |
2012年 | 2029篇 |
2011年 | 1943篇 |
2010年 | 1121篇 |
2009年 | 915篇 |
2008年 | 1407篇 |
2007年 | 1330篇 |
2006年 | 1214篇 |
2005年 | 1099篇 |
2004年 | 953篇 |
2003年 | 825篇 |
2002年 | 723篇 |
2001年 | 426篇 |
2000年 | 402篇 |
1999年 | 339篇 |
1998年 | 169篇 |
1997年 | 131篇 |
1996年 | 116篇 |
1995年 | 104篇 |
1994年 | 80篇 |
1993年 | 74篇 |
1992年 | 102篇 |
1991年 | 101篇 |
1990年 | 83篇 |
1989年 | 76篇 |
1988年 | 83篇 |
1987年 | 67篇 |
1986年 | 52篇 |
1985年 | 55篇 |
1984年 | 37篇 |
1983年 | 44篇 |
1982年 | 27篇 |
1981年 | 20篇 |
1980年 | 24篇 |
1979年 | 38篇 |
1978年 | 19篇 |
1977年 | 15篇 |
1976年 | 16篇 |
1972年 | 15篇 |
1969年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Haesung Yoon Yong Seung Lee Beom Jin Lim Kyunghwa Han Hyun Joo Shin Myung-Joon Kim Mi-Jung Lee 《European radiology》2020,30(4):1986-1996
To evaluate elasticity and perfusion change associated with fibrosis in a rabbit model of unilateral ureter obstruction using shear wave elastography (SWE) and contrast-enhanced ultrasonography (CEUS). Complete unilateral ureter obstruction by ligation was performed in the left kidney of 15 rabbits. Renal elasticity on SWE and perfusion change on CEUS at the renal cortex were measured before and after the operation. Histopathological renal fibrosis was quantified by the stained area ratio with Masson trichrome and Picrosirius red using ImageJ analysis. Renal elasticity and perfusion values were compared by the Mann-Whitney U test and Proc Mixed as a function of time. Spearman’s correlation was used to analyze differences between imaging values and fibrosis. The duration of imaging follow-up was up to 49 days, with interval imaging performed 1–3 times. Renal elasticity values were higher in obstructed kidneys compared to contralateral kidneys (31.0 kPa vs 16.4 kPa, p < 0.001) and increased according to postoperative time (0.46 kPa/day). With respect to renal fibrosis, SWE values were positively correlated with Masson trichrome (ρ = 0.651, p < 0.001) and Picrosirius red (ρ = 0.514, p = 0.007). Among CEUS parameters, mean transit time was negatively correlated with renal fibrosis by Masson trichrome (ρ = − 0.639, p = 0.001) and Picrosirius red (ρ = − 0.625, p = 0.001). Rise time and time to peak were positively correlated with renal fibrosis. Obstructive uropathy resulted in changes to both renal elasticity and perfusion. Renal fibrosis was moderately associated with increased renal cortical stiffness and both delayed and decreased cortical perfusion. • Obstructive uropathy causes changes in elasticity and perfusion in a rabbit model. • Renal fibrosis from obstructive uropathy increases renal cortical stiffness, and both delay and decrease cortical perfusion. 相似文献
992.
Park Chae Jung Han Kyunghwa Shin Haesol Ahn Sung Soo Choi Yoon Seong Park Yae Won Chang Jong Hee Kim Se Hoon Jain Rajan Lee Seung-Koo 《European radiology》2020,30(6):3035-3045
European Radiology - To identify significant prognostic magnetic resonance imaging (MRI) features and their prognostic value when added to clinical features in patients with isocitrate... 相似文献
993.
Jongha Park Soe Hee Ann Hyun Chul Chung Jong Soo Lee Shin-Jae Kim Scot Garg Eun-Seok Shin 《Heart and vessels》2014,29(1):58-64
Hemodialysis (HD)-induced myocardial ischemia is associated with an elevated cardiac troponin T, and is common in asymptomatic patients undergoing conventional HD. Remote ischemic preconditioning (RIPC) has a protective effect against myocardial ischemia–reperfusion injury. We hypothesized that RIPC also has a protective effect on HD-induced myocardial injury. Chronic HD patients were randomized to the control group or the RIPC group. RIPC was induced by transient occlusion of blood flow to the arm with a blood-pressure cuff for 5 min, followed by 5 min of deflation. Three cycles of inflation and deflation were undertaken before every HD session for 1 month (total 12 times). The primary outcome was the change in cardiac troponin T (cTnT) level at day 28 from baseline. Demographic and baseline laboratory values were not different between the control (n = 17) and the RIPC groups (n = 17). cTnT levels tended to decrease from day 2 in the RIPC group through to 28 days, in contrast to no change in the control group. There were significant differences in the change of cTnT level at day 28 from baseline [Control, median; ?0.002 ng/ml (interquartile range ?0.008 to 0.018) versus RIPC, median; ?0.015 ng/ml (interquartile range ?0.055 to 0.004), P = 0.012]. RIPC reduced cTnT release in chronic conventional HD patients, suggesting that this simple, cheap, safe, and well-tolerated procedure has a protective effect against HD-induced ischemia. 相似文献
994.
Sukjoong Oh Dong Hoe Koo Min-Jung Kwon Kihyun Kim Cheolwon Suh Chang-Ki Min Sung-Soo Yoon Ho-Jin Shin Deog-Yeon Jo Jae-Yong Kwak Jin Seok Kim Sang Kyun Sohn Young-Don Joo Hyeon-Seok Eom Sung-Hyun Kim Yang Soo Kim ChulSoo Kim Yeung-Chul Mun Hawk Kim Dong Soon Lee Jae Hoon Lee 《Annals of hematology》2014,93(8):1353-1361
This study was designed to evaluate the prevalence of chromosomal abnormalities and to identify the specific abnormalities associated with poor prognosis. A total of 2,474 patients whose conventional cytogenetics were available at the time of diagnosis were evaluated via a nationwide registry. Normal metaphase cytogenetics was observed in 2,012 patients (81.3%). Among the 462 patients with chromosomal abnormalities, there were 161 (34.8%) patients with hyperdiploidy, 197 (42.6%) with pseudodiploidy, 79 (17.1%) with hypodiploidy, and 25 (5.5%) with near-tetraploidy. Deletion 13 (Δ13) in metaphase was observed in 167 patients (6.8%). Fluorescent in situ hybridization (FISH) was carried out in 967 patients (39.1%), and 66 (13.7%) out of 482 and 63 (10.3%) out of 611 patients were positive for t(4;14) and del(17p), respectively. With a median follow-up duration of 25.1 months, the median overall survival (OS) was 51.2 months (95% confidence interval, 46.5–55.9 months). In univariate analysis, the following four chromosomal abnormalities were significantly associated with a poor survival outcome: Δ13, hypodiploidy, del(13q) in FISH, and del(17p) in FISH. In the subsequent multivariate analysis, in which del(13q) and del(17p) in FISH were excluded due to a relatively low number of patients, Δ13 and hypodiploid status were independently associated with a poor survival outcome after adjusting for important clinical factors, including age, sex, performance, beta2-microglobulin, albumin, and lactate dehydrogenase (LDH). Using conventional metaphase cytogenetics, we confirmed that both Δ13 and hypodiploid status were robust poor prognostic factors. The metaphase karyotyping should remain the primary cytogenetic tool and an essential investigation for risk stratification in newly diagnosed multiple myeloma patients. 相似文献
995.
Kazunari Tominaga Mototsugu Kato Hiroshi Takeda Yasuyuki Shimoyama Eiji Umegaki Ryuichi Iwakiri Kenji Furuta Koichi Sakurai Takeo Odaka Hiroaki Kusunoki Akihito Nagahara Katsuhiko Iwakiri Takahisa Furuta Kazunari Murakami Hiroto Miwa Yoshikazu Kinoshita Ken Haruma Shin’ichi Takahashi Sumio Watanabe Kazuhide Higuchi Motoyasu Kusano Kazuma Fujimoto Tetsuo Arakawa G-PRIDE Study Group 《Journal of gastroenterology》2014,49(10):1392-1405
Background
The aim of this study was to investigate the efficacy of rikkunshito (RKT), a traditional Japanese medicine, combined with proton pump inhibitor (PPI) in patients with PPI-refractory non-erosive reflux disease (NERD).Methods
Patients with PPI-refractory NERD (n = 242) were randomly assigned to the RKT group [rabeprazole (10 mg/day) + RKT (7.5 g/t.i.d.) for 8 weeks] or the placebo group (rabeprazole + placebo). After the 4- and 8-week treatments, we assessed symptoms and quality of life (QOL) using the Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease (FSSG), Gastrointestinal Symptom Rating Scale (GSRS), and Short-Form Health Survey-8 (SF-8).Results
There were no significant differences in FSSG and GSRS score improvement between these groups after the 4- and 8-week treatments. The mental component summary (MCS) scores of the SF-8 improved more in the RKT group (from 45.8 ± 8.1 to 48.5 ± 7.4) than in the placebo group (from 47.7 ± 7.1 to 48.4 ± 7.5) after the 4-week treatment (P < 0.05). The 8-week treatment with RKT was more effective for improvement of the degree of MCS score in patients with a low body mass index (<22) (P < 0.05) and significantly improved the acid-related dysmotility symptoms of FSSG in female and elderly patients (≥65 years).Conclusion
There were no significant differences in improvement of GERD symptoms in patients with PPI-refractory NERD between these groups. However, RKT may be useful for improving mental QOL in non-obese patients and acid-related dyspeptic symptoms, especially in women and the elderly. 相似文献996.
997.
998.
Min-Ho Shin Jin-Su Choi Jung-Ae Rhee Young-Hoon Lee Hae-Sung Nam Seul-Ki Jeong Kyeong-Soo Park Hye-Yeon Kim So-Yeon Ryu Seong-Woo Choi Hee Nam Kim Hye-Rim Song Jane A. Cauley Sun-Seog Kweon 《Atherosclerosis》2014
Objective
We evaluated the association between APOE polymorphism and carotid atherosclerosis in two large independent cohorts from South Korea.Methods
The datasets were from the Dong-gu Study (N = 9056) and the Namwon Study (N = 10,158). Carotid ultrasonography was performed to measure carotid intima-media thickness (IMT) and the presence of carotid plaques. The APOE polymorphism was determined by PCR-RFLP. We performed combined and separate analyses for the two datasets.Results
In the combined analysis, individuals with E2E2 or E2E3 genotype had a lower common carotid IMT compared with individuals with E3E3 genotype (0.684 mm vs. 0.736 mm, p = 0.007; 0.718 mm vs. 0.736 mm, p < 0.001, respectively). This association was very slightly attenuated but remained statistically significant after adjustment for blood lipids (0.690 mm vs. 0.736 mm, p = 0.033; 0.725 mm vs. 0.736 mm, p = 0.005, respectively). Compared with individuals with E3E3 genotype, individuals with E2E3 genotype had lower risk for carotid plaque (odds ratio (OR) = 0.83, 95% confidence interval (CI) = 0.75–0.93), while individuals with E3E4 genotype had a higher risk for carotid plaque (OR = 1.09, 95% CI = 1.00–1.20). After adjustment for blood lipids, ORs of E2E3 genotype for carotid plaque was slightly attenuated but remained significant (OR = 0.87 95% CI = 0.78–0.97), while OR of E3E4 genotype were slightly attenuated and not significant (OR = 1.08, 95% CI, 0.99–1.18).Conclusions
We found that APOE polymorphism is associated with carotid atherosclerosis and this association was partly mediated through blood lipid. Our results suggest that APOE polymorphism may influence atherosclerosis through non-lipid pathways. 相似文献999.
Won-Suk Lee Hye-Youn Kim Jae Yeon Seok Ho Hee Jang Yeon Ho Park So-Young Kim Dong Bok Shin Suntaek Hong 《Medicine》2014,93(28)
Recent evidence suggests that patient derived xenograft (PDX) models can maintain certain pathological and molecular features of the original disease. However, these characterizations are limited to immunohistochemistry or by tissue microarray analysis. We conducted a high-throughput sequencing of primary colon tumor and PDX has not been reported yet.Fresh primary colon cancer tissues that originate from surgery were implanted into the subcutaneous space of 6- to 8-week-old female BALB/c nu/nu or NOD/SCID mice and serially passaged in vivo. Ion AmpliSeq Cancer Hotspot Panel v2 (Ion Torrent) was used to detect frequent somatic mutations and similarity of molecular characteristics between the 10 patient tumors and matched PDX.Histologic and immunohistochemical analyses revealed a high degree of pathologic similarity including histologic architecture and expression of CEA, CK7, and CD20 between the patient and xenograft tumors. In 80% cases, all of the somatic mutations detected in primary tumor were concordantly detected in PDX models. However, 2 PDX models showed gained mutations such as PIK3CA or FBWX7 mutation.Ten patient-derived advanced colon cancer xenograft models were established. These models maintained the key characteristic features of the original tumors, suggesting useful tool for preclinical personalized medicine platform. 相似文献
1000.
Jong Bong Lee Tae Hwan Kim Wanshan Feng Hyeon Gwan Choi Atheer Zgair Soyoung Shin Sun Dong Yoo Pavel Gershkovich Beom Soo Shin 《Journal of pharmaceutical sciences》2019,108(2):1047-1052
For performance assessment of the lipid-based drug delivery systems (LBDDSs), in vitro lipolysis is commonly applied because traditional dissolution tests do not reflect the complicated in vivo micellar formation and solubilization processes. Much of previous research on in vitro lipolysis has mostly focused on rank-ordering formulations for their predicted performances. In this study, we have incorporated in vitro lipolysis with microsomal stability to quantitatively predict the oral bioavailability of a lipophilic antineoplastic drug bexarotene (BEX) administered in LBDDS. Two types of LBDDS were applied: lipid solution and lipid suspension. The predicted oral bioavailability values of BEX from linking in vitro lipolysis with microsomal stability for lipid solution and lipid suspension were 34.2 ± 1.6% and 36.2 ± 2.6%, respectively, whereas the in vivo oral bioavailability of BEX was tested as 31.5 ± 13.4% and 31.4 ± 5.2%, respectively. The predicted oral bioavailability corresponded well with the oral bioavailability for both formulations, demonstrating that the combination of in vitro lipolysis and microsomal stability can quantitatively predict oral bioavailability of BEX. In vivo intestinal lymphatic uptake was also assessed for the formulations and resulted in <1% of the dose, which confirmed that liver microsomal stability was necessary for correct prediction of the bioavailability. 相似文献