全文获取类型
收费全文 | 1759篇 |
免费 | 67篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 8篇 |
妇产科学 | 15篇 |
基础医学 | 315篇 |
口腔科学 | 52篇 |
临床医学 | 82篇 |
内科学 | 430篇 |
皮肤病学 | 24篇 |
神经病学 | 179篇 |
特种医学 | 120篇 |
外科学 | 168篇 |
综合类 | 9篇 |
预防医学 | 98篇 |
眼科学 | 44篇 |
药学 | 108篇 |
中国医学 | 2篇 |
肿瘤学 | 192篇 |
出版年
2023年 | 13篇 |
2022年 | 22篇 |
2021年 | 42篇 |
2020年 | 21篇 |
2019年 | 25篇 |
2018年 | 35篇 |
2017年 | 32篇 |
2016年 | 38篇 |
2015年 | 62篇 |
2014年 | 76篇 |
2013年 | 79篇 |
2012年 | 153篇 |
2011年 | 136篇 |
2010年 | 96篇 |
2009年 | 51篇 |
2008年 | 105篇 |
2007年 | 98篇 |
2006年 | 125篇 |
2005年 | 102篇 |
2004年 | 110篇 |
2003年 | 71篇 |
2002年 | 47篇 |
2001年 | 61篇 |
2000年 | 44篇 |
1999年 | 39篇 |
1998年 | 17篇 |
1997年 | 12篇 |
1996年 | 4篇 |
1995年 | 8篇 |
1994年 | 12篇 |
1993年 | 3篇 |
1992年 | 15篇 |
1991年 | 10篇 |
1990年 | 5篇 |
1989年 | 13篇 |
1988年 | 8篇 |
1987年 | 6篇 |
1986年 | 10篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1972年 | 6篇 |
1971年 | 3篇 |
1970年 | 3篇 |
排序方式: 共有1860条查询结果,搜索用时 15 毫秒
11.
Sun Jung Rhee Sang Hyun Paik Hwa Kyoon Shin Jai Soung Park Eun Hye Lee 《Korean journal of radiology》2012,13(3):342-344
We report on a 41-year-old woman with a chest wall desmoid tumour who was successfully treated with a computed tomography (CT)-guided steroid injection. She presented with a palpable mass in the right upper chest wall and was treated by surgical excision and postoperative radiation therapy due to recurrence of the mass at the surgical site. At 20 months after the second operation, a recurrent mass was again detected in the anterosuperior portion of the previous surgical site on CT. We performed a CT-guided steroid injection weekly for 4 weeks by applying a mixture of 3 mL of triamcinolone acetonide (40 mg/mL) and 3 mL of 1% Lidocaine, administering 4-6 mL of the mixture, to the lesion. Six months later, CT showed a marked decrease in the size of the mass. 相似文献
12.
13.
J I Yu J S Kim H C Park D H Lim Y Y Han H C Lim S W Paik 《The British journal of radiology》2013,86(1021):20120221
Objective
To measure the accuracy of position differences in anatomical landmarks in gated MRI and four-dimensional CT (4D-CT) fusion planning for radiation therapy in patients with hepatocellular carcinoma (HCC).Methods
From April to December 2009, gated MR and planning 4D-CT images were obtained from 53 inoperable HCC patients accrued to this study. Gated MRI and planning 4D-CT were conducted on the same day. Manual image fusions were performed by matching the vertebral bodies. Liver volumes and three specific anatomical landmarks (portal vein conjunction, superior mesenteric artery bifurcation, and other noticeable points) were contoured from each modality. The points chosen nearest the centre of the four landmark points were compared to measure the accuracy of fusion.Results
The average distance differences (±standard deviation) of four validation points were 5.1 mm (±4.6 mm), 5.6 mm (±6.2 mm), 5.4 mm (±4.5 mm) and 5.1 mm (±4.8 mm). Patients who had ascites or pulmonary disease showed larger discrepancies. MRI–CT fusion discrepancy was significantly correlated with positive radiation response (p<0.05).Conclusions
Approximately 5-mm anatomical landmark positional differences in all directions were found between gated MRI and 4D-CT fusion planning for HCC patients; the gap was larger in patients with ascites or pulmonary disease.Advances in knowledge
There were discrepancies of approximately 5 mm in gated MRI–CT fusion planning for HCC patients.Many studies have reported that the treatment response and survival of hepatocellular carcinoma (HCC) patients are related to the delivered radiation dose [1-3]. Recently, detailed information on HCC and liver motion gained from the use of advanced techniques, such as a fiducial marker combined with four-dimensional (4D) planning CT, has enabled the delivery of higher doses of radiation therapy (RT) with reduced normal liver toxicity [3-5].Although triphasic CT can provide much information about HCC, the lesion/liver contrast is higher in MRI than in CT [6,7]. To take advantage of these benefits, there have been many efforts to incorporate liver MRI in the RT planning process [8,9]. Moreover, several groups have demonstrated the feasibility of using cine-MRI and 4D-MRI to measure liver tumour motion for RT planning [10-12]. However, a consensus has not yet been reached on the best strategies to compensate for liver motion and adapt RT planning and delivery using planning 4D-CT combined with liver MRI.The primary goal of this prospective study was to evaluate the accuracy of gated MRI and 4D-CT fusion planning by measuring the discrepancies in the specific anatomical landmark points of the liver between exhale-phase images of gated liver MRI and 4D-CT. We also evaluated possible factors affecting gated liver MRI and 4D-CT fusion discrepancy and RT response. 相似文献14.
BackgroundThe purpose of this study is to introduce and review the clinical outcomes of a new technique for harvesting autogenous cancellous bone grafts in association with tibial intramedullary (IM) nailing.Materials and methodsWe retrospectively reviewed 21 patients who received autogenous cancellous bone grafts obtained from the entry portal of a tibial IM nail for fracture gaps, malalignment or nonunion in the lower extremities. All patients were scheduled to receive IM nailing or had already received IM nailing for the fixation of an ipsilateral tibia shaft fracture. A total of 33 patients who received only tibial IM nailing were selected as a control group. Through the follow-up, postoperative complications related to the bone harvest were monitored. Further by taking serial X-rays, radiographic changes of the donor site and the knee joint were closely observed. Knee pain (visual analogue scale (VAS)) and function (Lysholm knee score) were compared between the study group and the control group.ResultsAt the last follow-up, the average VAS in the study group was 1.28 (0–5), which was not significantly different from the control group (VAS: 1.36, range 0–7) (P = 0.985). The range of motion of the knee joint was similar in both groups, averaging 130.23° (range: 115–135°) and 131.36° (range: 115–135°), respectively. There was no significant difference in the Lysholm knee score between the study and control groups (P = 0.610). All patients exhibited complete fracture healing at an average of 6 months and no complications associated with the bone donor site were observed.ConclusionsBy using the new technique, autogenous cancellous bone grafting can be performed conveniently and safely to treat fracture gaps, malalignment or nonunion in the lower extremities without additional morbidity at the donor site. 相似文献
15.
Summary
Many determinants of parathyroid hormone (PTH) are unknown. In the National Health and Nutrition Examination Survey (NHANES), numerous factors not classically associated with calcium–phosphorus homeostasis, such as uric acid and smoking, are independently associated with PTH in adults without chronic kidney disease. Associations between serum phosphorus and PTH may vary by race.Introduction
Although PTH may be an important biomarker for osteoporosis and cardiovascular disease, many determinants of PTH are unknown. We investigated associations between demographic, dietary, and serum factors and PTH level.Methods
We studied 4,026 white, 1,792 black, and 1,834 Mexican-American adult participants without chronic kidney disease from the 2003–2004 and 2005–2006 NHANES.Results
The mean serum PTH level was 38.3?pg/ml for whites, 42.6?pg/ml for blacks, and 41.3?pg/ml for Mexican-Americans. After adjusting for diet, body mass index, serum levels of calcium, phosphorus, 25-hydroxyvitamin D, creatinine, and other factors, smokers compared to non-smokers had lower PTH, ranging from ?4.2?pg/ml (95% confidence interval (CI) ?7.3 to ?1.1) in Mexican-Americans to ?6.1?pg/ml (95% CI ?8.7 to ?3.5) in blacks. After multivariate adjustment, PTH was higher in females compared to males, ranging from 1.1?pg/ml (95% CI ?1.2 to 3.4) in Mexican-Americans to 4.5?pg/ml (95% CI 1.9 to 7.0) in blacks, and in older (>60?years) compared to younger participants (<30?years), ranging from 3.7?pg/ml (95% CI 1.3 to 6.1) in Mexican-Americans to 8.0?pg/ml (95% CI 5.4 to 10.7) in blacks. Higher uric acid was associated with higher PTH. In whites only, lower serum phosphorus and lower serum retinol were associated with higher PTH.Conclusions
Numerous factors not classically associated with calcium–phosphorus homeostasis are independently associated with PTH and should be considered in future studies of PTH and chronic disease. Additional research is needed to elucidate mechanisms underlying identified associations with PTH and to explore possible racial differences in phosphorus handling. 相似文献16.
Ko BH Paik JY Jung KH Bae JS Lee EJ Choe YS Kim BT Lee KH 《European journal of nuclear medicine and molecular imaging》2008,35(3):554-561
Objectives Small animal imaging with meta-iodobenzylguanidine (MIBG) allows characterization of animal models, optimization of tumor
treatment strategies, and monitoring of gene expression. Anesthetic agents, however, can affect norepinephrine (NE) transport
and systemic sympathetic activity. We thus elucidated the effects of anesthetic agents on MIBG transport and biodistribution.
Methods SK-N-SH neuroblastoma and PC-12 pheochromocytoma cells were measured for 123I-MIBG uptake after treatment with ketamine (Ke), xylazine (Xy), Ke/Xy, or pentobarbital (Pb). NE transporters were assessed
by Western blots. Normal ICR mice and PC-12 tumor-bearing mice were injected with 123I-MIBG 10 min after anesthesia with Ke/Xy, Ke, Xy, or Pb. Plasma NE levels and MIBG biodistribution were assessed.
Results Cellular 123I-MIBG uptake was dose-dependently inhibited by Ke and Xy but not by Pb. Treatment for 2 h with 300 μM Ke, Xy, and Ke/Xy decreased
uptake to 46.0 ± 1.6, 24.8 ± 1.5, and 18.3 ± 1.6% of controls. This effect was completely reversed by fresh media, and there
was no change in NE transporter levels. In contrast, mice anesthetized with Ke/Xy showed no decrease of MIBG uptake in target
organs. Instead, uptakes and organ-to-blood ratios were increased in the heart, lung, liver, and adrenals. Plasma NE was notably
reduced in the animals with corresponding decreases in blood MIBG, which partly contributed to the increase in target organ
uptake.
Conclusion In spite of their inhibitory effect at the transporter level, Ke/Xy anesthesia is a satisfactory method for MIBG imaging that
allows favorable target tissue uptake and contrast by reducing circulating NE and MIBG.
Bong-Ho Ko and Jin-Young Paik equally contributed to this work.
This work was supported by the Korea Research Foundation Grant KRF-2005-202-E00116.
Presented in part at the fifth Annual Meeting of the Society for Molecular Imaging, Hawaii, August 30–September 2, 2006. 相似文献
17.
Nam Chull Paik 《The spine journal》2010,10(11):e10-e13
Background context
Cervical spondylolysis, which is defined as a cleft between the superior and inferior articular facets of the articular pillar, is a rare condition. The sixth cervical vertebra (C6) is the level most commonly affected. Cases involving C2, C3, C4, or C5 have also been reported. However, to date, no case of C7 spondylolysis has been reported.Purpose
To present a rare case of bilateral spondylolysis of the seventh cervical vertebra (C7) in a 58-year-old man.Study design
A case report.Methods
A 58-year-old man visited our hospital with chronic posterior neck pain radiating to the left upper extremity. Magnetic resonance imaging (MRI) study revealed left foraminal disc herniations at C5–C6 and C6–C7. Cervical spondylolysis involving C7 was discovered incidentally during computed tomography (CT)–guided transforaminal steroid injection. Plain radiographs, CT images, and MRIs were reviewed thoroughly once again.Results
The patient’s symptoms were relieved after he received CT-guided transforaminal steroid injections. Plain radiographs revealed a radiolucent defect in the articular pillar and cleft at the spinous process of C7. Computed tomography confirmed bilateral spondylolysis and spina bifida occulta of the C7 vertebra. Magnetic resonance imaging revealed absence of edema, which was suggestive of a chronic lesion.Conclusion
Involvement of C7 is not exceptional in a case of cervical spondylolysis. 相似文献18.
Seong Jin Jo Hyoseung Shin Seung Hwan Paik Sun Jae Na Yingji Jin Won Seok Park Su Na Kim Oh Sang Kwon 《ANNALS OF DERMATOLOGY》2013,25(2):218-222
Background
Graying of hair-a sign of aging-raises cosmetic concerns. Individuals with gray hair often look older than others their age; therefore, some dye their hair for aesthetic purposes. However, hair colorants can induce many problems including skin irritation, allergic reaction and hair-breakage.Objective
This randomized, double-blind clinical trial was performed in order to examine the effects of APHG-1001, a compound including an extract from Pueraria lobata, on graying hair.Methods
A total of 44 female subjects were randomly treated with either APHG-1001 or placebo twice daily for 24 weeks. Using the phototrichogram analysis, a count of newly developed gray hair was estimated. Investigator assessment and subject self-assessment were also performed in order to evaluate the efficacy of the compound.Results
The mean number of newly developed gray hair at 24 weeks was 6.3/cm2 in the APHG-1001 group and 11.4/cm2 in the placebo group; the difference was statistically significant (p<0.05). However, the investigator assessment and subject self-assessment did not show any significant change in the gross appearance of hair grayness by the end of the study. No severe adverse events in either group were observed. Moreover, the incidence of adverse events did not differ between the groups.Conclusion
This clinical trial revealed that APHG-1001, which contains an extract of P. lobata, could prevent the development of new gray hair without any remarkable adverse effects. Thus, it can be considered as a viable treatment option for the prevention of gray hair. 相似文献19.
Tae Hwan Kim Soyoung Shin Cornelia B. Landersdorfer Yong Ha Chi Soo Heui Paik Jayhyuk Myung Rajbharan Yadav Stefan Horkovics-Kovats Jürgen B. Bulitta Beom Soo Shin 《The AAPS journal》2015,17(5):1210-1223
Enterohepatic recirculation (EHC) can greatly enhance plasma drug exposures and therapeutic effects. This study aimed to develop a population pharmacokinetic model that can simultaneously characterize the extent and time-course of EHC in three species using fimasartan, a novel angiotensin II receptor blocker, as a model drug. All fimasartan plasma concentration profiles in 32 rats (intravenous doses, 0.3–3 mg/kg; oral doses, 1–10 mg/kg), 34 dogs (intravenous doses, 0.3–1 mg/kg; oral doses, 1–10 mg/kg), and 42 healthy volunteers (single or multiple oral doses, 20–480 mg) were determined via liquid chromatography-tandem mass spectrometry (LC-MS/MS) and simultaneously modeled in S-ADAPT. The proposed model quantitatively characterized EHC in three species after oral and intravenous dosing. The median (range) fraction of drug undergoing recirculation was 76.3% (64.9–88.7%) in rats, 33.3% (24.0–45.9%) in dogs, and 65.6% (56.5–72.0%) in humans. In the presence compared with the absence of EHC, the area under the curve in plasma was predicted to be 4.22-fold (2.85–8.85) as high in rats, 1.50-fold (1.32–1.85) in dogs, and 2.91-fold (2.30–3.57) in humans. The modeled oral bioavailability in rats (median (range), 38.7% (20.0–59.8%)) and dogs (median, 7.13% to 15.4%, depending on the formulation) matched the non-compartmental estimates well. In humans, the predicted oral bioavailability was 25.1% (15.1–43.9%) under fasting and 18.2% (12.2–31.0%) under fed conditions. The allometrically scaled area under the curve predicted from rats was 420 ng ⋅ h/mL for 60 mg fimasartan compared with 424 ± 63 ng ⋅ h/mL observed in humans. The developed population pharmacokinetic model can be utilized to characterize the impact of EHC on plasma drug exposure in animals and humans.
Electronic supplementary material
The online version of this article (doi:10.1208/s12248-015-9764-2) contains supplementary material, which is available to authorized users.KEY WORDS: animal to human scaling, enterohepatic recirculation, fimasartan, population pharmacokinetics, S-ADAPT 相似文献20.