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31.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts. 相似文献
32.
Amphiphilic amino acid copolymers as stabilizers for the preparation of nanocrystal dispersion 总被引:2,自引:0,他引:2
Jonghwi Lee Soo-Jeong Lee Ji-Yeun Choi Ji Youn Yoo Cheol-Hee Ahn 《European journal of pharmaceutical sciences》2005,24(5):441-449
The recent advance of particle size engineering in nanometer ranges has widened the formulation opportunities of relatively water-insoluble drugs. However, the ‘nanoformulation’ suffers from a lack of systematic understanding about the requirements of polymeric stabilizers. Furthermore, the polymers that can be used for the preparation of nanocrystals are so limited that finding a proper stabilizer for a given formulation is often difficult. In this study, amino acid copolymers whose properties can systematically be tailored are developed, and their morphological and compositional effects are investigated. Copolymers containing lysine (K) as their hydrophilic segments, and phenylalanine (F) or leucine (L) as their hydrophobic segments successfully produce stable nanocrystals (200–300 nm) in water, while copolymers of K and alanine (A) could not generate nanosized particles. Not the morphology but the hydrophobicity of copolymers seems to be a critical parameter in the preparation of drug nanocrystals by wet comminution. The effective stabilization performance of copolymers requires the hydrophobic moiety content to be higher than 15 mol%. Comminution for only 5 min is long enough for nanocrystal preparation, and the crystallinity of drug is found intact after the processing. 相似文献
33.
Ye Won Jung Soo Youn Song Won Kyo Shin Su Min Chung Ji Won Park Heon Jong Yoo 《Medicine》2022,101(43)
The COVID 19 pandemic is far from over, and vaccines remain important tool for fighting the disease. As the preventive effects of the COVID-19 vaccine emerges, it is likely that the perception of importance and safety of vaccines have a positive effect on the acceptance of other vaccines. However, it is still unclear how COVID-19 pandemic has affected the general vaccination perception and acceptance. Therefore, the objective of this study was to investigate the impact of the COVID-19 pandemic on the perception of HPV vaccination. This study involved an offline survey of 161 women aged between 20 and 49 years who visited the gynecologic clinic at Chung-nam National University Sejong Hospital from January 2021 to June 2021. The questionnaire consists of items related to experience and knowledge of COVID-19 and HPV viruses, as well as attitudes toward HPV vaccination. Knowledge about COVID-19 virus and HPV correlated positively with their experiences (P = .011 and P = .045, respectively). Positive attitude was increased, and negative attitude was reduced toward HPV vaccination in the COVID-19 pandemic era. Participants stated that accurate information and cost reduction about HPV vaccine was needed to increase the HPV vaccination rate. During the COVID-19 pandemic era, positive attitudes towards HPV vaccination have tended to increase. To increase the HPV vaccination rate, public efforts are needed for further information and cost reduction. 相似文献
34.
Namhee Kim Kwang Hyuk Seok Soyoun Shin Boram Kim Hyunwoong Park Eun Youn Roh Jong Hyun Yoon Sue Shin 《Journal of Korean medical science》2022,37(46)
BackgroundWhole genome sequencing (WGS) is an increasingly useful tool for tuberculosis (TB) diagnosis and disease management. In this study, we evaluated the utility of user-friendly WGS tools in reporting resistance profiles and identifying lineages of clinical TB isolates from South Korea.MethodsForty clinical samples from TB patients showing discrepancies between their rapid molecular and conventional drug susceptibility tests were used in this study. Among these clinical isolates, 37 strains were successfully evaluated via WGS software, using the GenTB, TB Profiler, PhyResSE, CASTB, and Mykrobe.ResultsMore accurate and faster susceptibility results could be obtained with isoniazid than with rifampin. Using the phenotypic test as the gold standard, the isoniazid concordance rate between phenotypic drug susceptibility test (DST) and WGS (GenTB: 45.9%, TB profiler: 40.5%, PhyResSE: 40.5%, CASTB: 48.6%, and Mykrobe: 43.2%) was much higher than between phenotypic DST and rapid molecular genotypic DST (18.9%) among the 37 strains. In contrast, the rifampin concordance rate between phenotypic DST and WGS and that between phenotypic DST and rapid molecular genotypic DST was similar (81.1–89.2%). We also found novel mutations associated with INH in katG and ahpC gene region, not covered by the line probe assay. In addition, lineage analysis identified 81.1% of these samples as L2 East Asian lineage strains, and 18.9% as L4 Euro-American lineage strains.ConclusionWGS may play a pivotal role in TB diagnosis and the detection of drug resistance, genetic diversity, and transmission dynamics in the near future because of its accuracy, speed, and extensibility. 相似文献
35.
Seung Hyuk Lim Harry Jung Dong Hyuk Youn Tae Yeon Kim Sung Woo Han Bong Jun Kim Jae Jun Lee Jin Pyeong Jeon 《Journal of Korean Neurosurgical Society》2022,65(5):680
ObjectiveThe influence of moderate-to-severe traumatic brain injury (TBI) on acute pulmonary injury is well established, but the association between acute pulmonary injury and mild TBI has not been well studied. Here, we evaluated the histological changes and fluctuations in inflammatory markers in the lungs to determine whether an acute pulmonary inflammatory response occurred after mild TBI. MethodsMouse models of mild TBI (n=24) were induced via open-head injuries using a stereotaxic impactor. The brain and lungs were examined 6, 24, and 72 hours after injury and compared to sham-operated controls (n=24). Fluoro-Jade B staining and Astra blue and hematoxylin staining were performed to assess cerebral neuronal degeneration and pulmonary histological architecture. Quantitative real-time polymerase chain reaction analysis was done to measure inflammatory cytokines. ResultsIncreased neuronal degeneration and the mRNA expression of interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-10, and transforming growth factor (TGF)-β were observed after mild TBI. The IL-6, TNF-α, and TGF-β levels in mice with mild TBI were significantly different compared to those of sham-operated mice 24 hours after injury, and this was more pronounced at 72 hours. Mild TBI induced acute pulmonary interstitial edema with cell infiltration and alveolar morphological changes. In particular, a significant infiltration of mast cells was observed. Among the inflammatory cytokines, TNF-α was significantly increased in the lungs at 6 hours, but there was no significant difference 24 and 72 hours after injury. ConclusionMild TBI induced acute pulmonary interstitial inflammation and alveolar structural changes, which are likely to worsen the patient’s prognosis. 相似文献
36.
Tomohisa Okada Thai Akasaka Dinh HD Thuy Tadashi Isa 《Magnetic resonance in medical sciences》2022,21(4):531
After introduction of the first human 7 tesla (7T) system in 1999, 7T MR systems have been employed as one of the most advanced platforms for human MR research for more than 20 years. Currently, two 7T MR models are approved for clinical use in the U.S.A. The approval facilitated introduction of the 7T system, summing up to around 100 worldwide. The approval in Japan is much awaited. As a clinical MR scanner, the 7T MR system is drawing attention in terms of safety.Several large-sized studies on bioeffects have been reported for vertigo, dizziness, motion disturbances, nausea, and others. Such effects might also be found in MR workers and researchers. Frequency and severity of reported bioeffects will be presented and discussed, including their variances. The high resonance frequency and shorter RF wavelength of 7T increase the concern about the safety. Homogeneous RF pulse excitation is difficult even for the brain, and a multi-channel parallel transmit (pTx) system is considered mandatory. However, pTx may create a hot spot, which makes the estimation of specific absorption rate (SAR) to be difficult. The stronger magnetic field of 7T causes a large force of displacement and heating on metallic implants or devices, and the scan of patients with them should not be conducted at 7T. However, there are some opinions that such patients might be scanned even at 7T, if certain criteria are met. This article provides a brief review on the effect of the static magnetic field on humans (MR subjects, workers, and researchers) and neurons, in addition to scan sound, SAR, and metal implants and devices. Understanding and avoiding adverse effects will contribute to the reduction in safety risks and the prevention of incidents. 相似文献
37.
Sohyun Park Youn Woo Lee Jaeseong Oh Su Jin Kim Sukmook Lee HoYoung Lee 《CTS Clinical and Translational Science》2022,15(12):2938
Anti‐angiogenic antibodies are widely used in the treatment of neovascular macular degeneration. Human antibody targeting C‐type lectin domain family 14 member A (CLEC14a) is potential therapeutic agents owing to its antiangiogenic activity. In the present study, we aimed to predict the human intraocular pharmacokinetic (PK) properties of an anti‐CLEC14a antibody. I‐125 labeled aflibercept and anti‐CLEC14a antibody were intravitreally injected into mice, rats, and rabbits. Single photon emission computed tomography/computed tomography imaging was performed, and the intraocular radioactivity concentration (%ID/ml) was obtained. The PK parameters in those three animal species were obtained by compartmental analysis. The PK parameters in humans were estimated by allometric scaling of the animal PK parameters with consideration of the hydrodynamic radius of the antibody. The mean half‐life values of intraocular I‐125‐labeled aflibercept in mice, rats, and rabbits were 1.13 days, 1.25 days, and 4.91 days, respectively, by analysis with a one‐compartment model. The predicted human half‐life of intraocular aflibercept was 5.75 days based on vitreal volume by allometric scaling. The half‐life values of intraocular I‐125‐labeled anti‐CLEC14a in mice, rats and rabbits were 1.05 days, 1.84 days, and 6.37 days, respectively, by analysis with a one‐compartment model. The predicted human half‐life of intraocular anti‐CLEC14a was 10.29 days based on vitreal volume. According to the hydrodynamic volume of the anti‐CLEC14a, the predicted human half‐life of intraocular anti‐CLEC14a was 9.81 days. The PK characteristics of the intraocular anti‐CLEC14a antibody were evaluated noninvasively in animals using I‐125 labeling, and the intraocular PK characteristics in humans were predicted using these animal data. This methodology can be applied for the development of new antiangiogenic antibodies to treat macular degeneration.Study Highlights
- WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
- WHAT QUESTION DID THIS STUDY ADDRESS?
- WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
- HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
38.
Do Thi Ha Quan Cheng Chen Tran Manh Hung Ui Joung Youn Tran Minh Ngoc Phuong Thien Thuong Hong Jin Kim Yeon Hee Seong Byung Sun Min KiHwan Bae 《Archives of pharmacal research》2009,32(2):177-183
Chromatographic separation of the EtOAc fraction from the leaf and stem of Vitis amurensis led to the isolation of six oligostilbenoids (i.e., r-2-viniferin (1), trans-amurensin B (2), trans-ɛ-viniferin (3), gnetin H (4), amurensin G (5), (+)-ampelopsin A (8)) and four stilbenoids (i.e., trans-resveratrol (6), (+)-ampelopsin F (7), piceatannol (9), and trans-piceid (10)). The structures have been identified on the basis of spectroscopic evidence and physicochemical properties. The isolates
were investigated for cytotoxic activity against three cancer cell lines in vitro using the MTT assay method. Amurensin G (5) and trans-resveratrol (6) showed significant cytotoxic activity against L1210, K562 and HTC116 cancer cell lines with IC50 values ranging from 15.7 ± 2.1 to 30.9 ± 1.8 μM. (+)-Ampelopsin A (8) and trans-piceid (10) exhibited considerable cytotoxic activity against L1210 (IC50 values of 30.6 ± 4.1 and 28.7 ± 2.81 μM, respectively) and K562 (IC50 values of 38.6 ± 0.82 and 24.6 ± 0.76 μM, respectively). Gnetin H (4) showed only weak cytotoxic activity against L1210 with an IC50 value of 40.1 ± 4.23 μM. On the other hand, r-2-viniverin (1), trans-amurensin B (2), trans-ɛ-viniferin (3), (+)-ampelopsin F (7), and piceatannol (9) exhibited no activity on three cancer cell lines. 相似文献
39.
Ui Joung Youn Nighat Fatima Quan Cheng Chen Sungwook Chae Tran Manh Hung Byung‐Sun Min 《Phytotherapy research : PTR》2013,27(9):1419-1422
Two neolignans, 4′‐methoxymagndialdehyde (1) and magnaldehyde B (2), were isolated from the stem bark of Magnolia officinalis (Magnoliaceae), evaluated for apoptosis‐inducing effects in human cervical epitheloid carcinoma HeLa cells. The apoptosis‐inducing activity of compounds 1 and 2 were assessed by DNA content using flow cytometric analysis. In the immunoblotting analysis, the treatment with 1 and 2 resulted in the cleavage of procaspase‐8 and ‐3 and poly(ADP‐ribose)polymerase into active forms. In addition, in vivo, the administration of 2 to Lewis lung carcinoma‐inoculated mice evidenced a significant inhibition of tumor growth (volume) with reduction of 28.7% at concentration of 20 mg/kg, as compared with the control mice. These findings suggest that 2 can inhibit the proliferation of tumor cells, and might be an anti‐tumoric agent. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
40.
Jeong Min Yang Su bin Lee Ye ji Kim Douk young Chon Jong Youn Moon Jae Hyun Kim 《Medicine》2022,101(32)
This empirical study identifies the negative aspects of private health insurance (PHI) by analyzing the association between subjective health conditions, 2 weeks of outpatient care, chronic diseases, and hospitalizations for 1 year. We used frequency analysis, χ2 testing, an analysis of variance, and logistic and multiple logistic regression models to analyze the association between PHI and subjective health conditions, outpatient care, chronic disease status, and hospitalization. The PHI group had good subjective health but had more outpatient care for 2 weeks. There were few chronic diseases in the private insurance group, and there was no significant difference in hospitalizations for 1 year. Hospitalization may occur when essential medical care is required, regardless of health insurance type. This study confirmed that as the PHI lowers the burden of personal medical expenses, the PHI can lead to an increase in the medical resource expenditures on the outpatient medical service and higher public health costs. The government should work to redefine the role of private and national health insurance. Also, the effectiveness of PHI should be reevaluated so that it does not lead to indiscriminate use of medical services by minimizing the burden of private insurance. 相似文献