全文获取类型
收费全文 | 14249篇 |
免费 | 796篇 |
国内免费 | 240篇 |
专业分类
耳鼻咽喉 | 287篇 |
儿科学 | 264篇 |
妇产科学 | 339篇 |
基础医学 | 2055篇 |
口腔科学 | 397篇 |
临床医学 | 1274篇 |
内科学 | 2882篇 |
皮肤病学 | 275篇 |
神经病学 | 1076篇 |
特种医学 | 732篇 |
外科学 | 1890篇 |
综合类 | 202篇 |
一般理论 | 1篇 |
预防医学 | 781篇 |
眼科学 | 445篇 |
药学 | 1251篇 |
中国医学 | 173篇 |
肿瘤学 | 961篇 |
出版年
2023年 | 98篇 |
2022年 | 246篇 |
2021年 | 467篇 |
2020年 | 208篇 |
2019年 | 334篇 |
2018年 | 441篇 |
2017年 | 308篇 |
2016年 | 396篇 |
2015年 | 591篇 |
2014年 | 656篇 |
2013年 | 894篇 |
2012年 | 1294篇 |
2011年 | 1219篇 |
2010年 | 695篇 |
2009年 | 594篇 |
2008年 | 803篇 |
2007年 | 802篇 |
2006年 | 742篇 |
2005年 | 635篇 |
2004年 | 560篇 |
2003年 | 461篇 |
2002年 | 416篇 |
2001年 | 379篇 |
2000年 | 329篇 |
1999年 | 247篇 |
1998年 | 123篇 |
1997年 | 80篇 |
1996年 | 67篇 |
1995年 | 70篇 |
1994年 | 66篇 |
1993年 | 57篇 |
1992年 | 123篇 |
1991年 | 98篇 |
1990年 | 98篇 |
1989年 | 105篇 |
1988年 | 95篇 |
1987年 | 72篇 |
1986年 | 54篇 |
1985年 | 57篇 |
1984年 | 32篇 |
1983年 | 30篇 |
1982年 | 25篇 |
1981年 | 17篇 |
1980年 | 21篇 |
1978年 | 19篇 |
1977年 | 17篇 |
1976年 | 16篇 |
1975年 | 19篇 |
1974年 | 17篇 |
1958年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Becker-Catania SG Chen G Hwang MJ Wang Z Sun X Sanal O Bernatowska-Matuszkiewicz E Chessa L Lee EY Gatti RA 《Molecular genetics and metabolism》2000,70(2):122-133
Previous studies on a limited number of ataxia-telangiectasia (A-T) patients with detectable levels of intracellular ATM protein have suggested a genotype/phenotype correlation. We sought to elucidate this possible correlation by comparing ATM protein levels with mutation types, radiosensitivity, and clinical phenotype. In this study, Western blot analysis was used to measure ATM protein in lysates of lymphoblastoid cell lines (LCLs) from 123 unrelated A-T patients, 10 A-T heterozygotes, and 10 patients with phenotypes similar to A-T. Our Western blot protocol can detect the presence of ATM protein in as little as 1 microg of total protein; at least 25 microg of protein was tested for each individual. ATM protein was absent in 105 of the 123 patients (85%); most of these patients had truncating mutations. The remaining subset of 18 patients (15%) had reduced levels of normal-sized ATM protein; missense mutations were more common in this subset. We used a colony survival assay to characterize the phenotypic response of the LCLs to radiation exposure; patients with or without detectable ATM protein were typically radiosensitive. Nine of 10 A-T heterozygotes also had reduced expression of ATM, indicating that both alleles contribute to ATM protein production. These data suggest that although ATM-specific mRNA is abundant in A-T cells, the abnormal ATM protein is unstable and is quickly targeted for degradation. We found little correlation between level of ATM protein and the type of underlying mutation, the clinical phenotype, or the radiophenotype. 相似文献
82.
Kim SN Rhee JH Song YH Park DY Hwang M Lee SL Kim JE Gim BS Yoon JH Kim YJ Kim-Ha J 《Neurobiology of aging》2005,26(7):1083-1091
Previous gene expression profiling studies in Drosophila have provided clues for understanding the aging process at the gene expression level. For a detailed understanding, studies of specific regions of the body are necessary. We therefore employed microarray analysis to examine gene expression changes in the Drosophila head during aging. Six hundred and eighty-four of the 5405 genes present in the microarray showed significant age-dependent changes as determined by significance analysis of microarray (SAM) (q < 0.05). The biological significance of the changes was analyzed using the gene annotations provided by the Gene Ontology Consortium. Major changes involved genes affecting energy metabolism (proton transport, energy pathways, oxidative phosphorylation) and neuronal function, especially responses to light. Genes involved in protein catabolism and several other metabolic processes also showed age-dependent changes. Most of the changes were reductions in gene expression and occurred before day 13 of adult life. After day 13, the age-dependent gene expression changes were relatively smaller than earlier life. Interestingly, the two biological processes of major gene expression changes are related to the two known environmental changes that increase life span in Drosophila: caloric restriction and light reduction. Our findings suggest that light signaling and energy metabolism may be important biological processes affected by aging and be interesting targets for the further investigation related to the longevity in Drosophila. 相似文献
83.
BACKGROUND: The skin of patients with atopic dermatitis (AD) exhibits a striking susceptibility to colonization and infection by Staphylococcus aureus. The exotoxins secreted by S. aureus can act as superantigens and classic allergens, inducing the production of functionally relevant specific IgE antibodies. The aim of this study was to compare the levels and positive rates of serum staphylococcal enterotoxin A (SEA)- and staphylococcal enterotoxin B (SEB)-specific IgE between atopic children with and without AD. METHODS: Sixty children with AD, 55 children with respiratory allergy without AD, and 24 nonatopic healthy children were studied. The levels and positive rates of serum SEA- and SEB-specific IgE were compared among three groups. The correlation between the levels or positive rates of serum SEA/SEB-specific IgE and the severity of AD or the presence of previous skin infections was studied. RESULTS: The children with AD had significantly higher levels and positive rates of serum SEA- and SEB-specific IgE than the atopic children without AD (P < 0.001) and the nonatopic children (P < 0.001). There was no significant difference in the levels and positive rates of serum SEA- and SEB-specific IgE between the atopic children without AD and the nonatopic children. With or without adjustment for the potential confounding effect of total serum IgE levels, the levels and positive rates of serum SEA- and SEB-specific IgE were significantly correlated with severity of AD (P <0.005), but they were not significantly different between AD children with and without previous skin infections. CONCLUSIONS: SEA and SEB may contribute to chronic inflammation and exacerbation of AD through the IgE-mediated immune response. 相似文献
84.
Yu Seong Hyeon Hur Young Hoe Hwang Eu Chang Kim Myung Soo Chung Ho Seok Lee Byung Chan Heo Suk Hee Choi Chan Hwang Jun Eul Bae Woo Kyun Jung Seung Il Kwon Dong Deuk 《International urology and nephrology》2021,53(1):69-75
International Urology and Nephrology - Multidetector computed tomographic urography (MDCTU) is not yet sufficient to be used in the clinical staging of upper tract urothelial carcinoma (UTUC). This... 相似文献
85.
Weranja Ranasinghe Daniel D. Shapiro Hyunsoo Hwang Xuemei Wang Chad A. Reichard Mohamed Elsheshtawi Mary F. Achim Tharakeswara Bathala Chad Tang Ana Aparicio Shi-Ming Tu Nora Navone Timothy C. Thompson Louis Pisters Patricia Troncoso John W. Davis Brian F. Chapin 《European urology》2021,79(2):298-306
BackgroundDuctal prostate adenocarcinoma (DAC) is a rare, aggressive, histologic variant of prostate cancer that is treated with conventional therapies, similar to high-risk prostate adenocarcinoma (PAC).ObjectiveTo assess the outcomes of men undergoing definitive therapy for DAC or high-risk PAC and to explore the effects of androgen deprivation therapy (ADT) in improving the outcomes of DAC.Design, setting, and participantsA single-center retrospective review of all patients with cT1–4/N0–1 DAC from 2005 to 2018 was performed. Those undergoing radical prostatectomy (RP) or radiotherapy (RTx) for DAC were compared with cohorts of high-risk PAC patients.Outcome measurements and statistical analysisMetastasis-free survival (MFS) and overall survival (OS) rates were analyzed using Kaplan-Meier and Cox regression models.Results and limitationsA total of 228 men with DAC were identified; 163 underwent RP, 34 underwent RTx, and 31 had neoadjuvant therapy prior to RP. In this study, 163 DAC patients and 155 PAC patients undergoing RP were compared. Similarly, 34 DAC patients and 74 PAC patients undergoing RTx were compared. DAC patients undergoing RP or RTx had worse 5-yr MFS (75% vs 95% and 62% vs 93%, respectively, p < 0.001) and 5-yr OS (88% vs 97% and 82% vs 100%, respectively, p < 0.05) compared with PAC patients. In the 76 men who received adjuvant/salvage ADT after RP, DAC also had worse MFS and OS than PAC (p < 0.01). A genomic analysis revealed that 10/11 (91%) DACs treated with ADT had intrinsic upregulation of androgen-resistant pathways. Further, none of the DAC patients (0/15) who received only neoadjuvant ADT prior to RP had any pathologic downgrading. The retrospective nature was a limitation.ConclusionsMen undergoing RP or RTx for DAC had worse outcomes than PAC patients, regardless of the treatment modality. Upregulation of several intrinsic resistance pathways in DAC rendered ADT less effective. Further evaluation of the underlying biology of DAC with clinical trials is needed.Patient summaryThis study demonstrated worse outcomes among patients with ductal adenocarcinoma of the prostate than among high-grade prostate adenocarcinoma patients, regardless of the treatment modality. 相似文献
86.
87.
Weiss Anna Campbell Jordan Ballman Karla V. Sikov William M. Carey Lisa A. Hwang E. Shelley Poppe Matthew M. Partridge Ann H. Ollila David W. Golshan Mehra 《Annals of surgical oncology》2021,28(11):5960-5971
Annals of Surgical Oncology - De-escalation of axillary surgery after neoadjuvant chemotherapy (NAC) requires careful patient selection. We seek to determine predictors of nodal pathologic complete... 相似文献
88.
Hae Sang Lee Jung Gi Rho Chang Dae Kum Jung Sub Lim Jin Soon Hwang 《Journal of clinical densitometry》2021,24(2):275-280
Previous studies have reported reduced bone mineral density (BMD) in patients with hyperthyroidism. We assessed the association of BMD in children and adolescents with Graves’ disease (GD) after correcting for potential confounders affecting BMD such as age, sex, and pubertal status. Forty-four children and adolescents with GD and 172 age- and sex-matched healthy controls were enrolled in this study. We analyzed auxological features, BMD, and levels of thyroid hormone, thyroid-stimulating hormone, and thyroid autoantibodies. We measured BMD by dual-energy X-ray absorptiometry at the time of diagnosis in all patients. The mean age of all patients with GD (9 boys and 32 girls) was 12.1 ± 2.2 years (range, 7.0–16.0). Their initial mean free T4 and thyroid-stimulating hormone levels were 3.51 ± 1.56 ng/dL and 0.04 ± 0.03 IU/L, respectively. The mean BMD Z-scores of the lumbar spine (LS), femoral neck, and total body less head of patients with GD were significantly lower than those of control subjects. Eleven patients (26.8%) had low bone density (LS BMD Z-scores < ?2.0). To identify correlations of patient characteristics with BMD Z-scores at each site, alkaline phosphatase had a significant negative correlation with BMD Z-scores at LS and femoral neck, but not total body less head (r = ?0.441; p = 0.004 and r = ?0.351; p = 0.025, respectively). Children and adolescents with newly diagnosed GD had lower bone mass than their healthy peers. These results suggest that BMD measurement at initial evaluation may be necessary in this population. 相似文献
89.
Kou H.-W. Yeh C.-N. Tsai C.-Y. Hsu J.-T. Wang S.-Y. Lee C.-W. Yu M.-C. Hwang T.-L. 《Hernia》2021,25(5):1317-1324
Hernia - Occult inguinal hernias (IH) predispose peritoneal dialysis (PD) patients to the symptomatic IH formation after starting PD, which may cause complications. We conducted a retrospective... 相似文献
90.
Soo Kyung Cho Myung Soo Kim Ho Seok Chung Eu Chang Hwang Seung Il Jung Dongdeuk Kwon Kwangsung Park 《Translational andrology and urology》2021,10(3):1347
Indwelling urethral catheter placement is a common and comparatively safe procedure. Misplacement of a urethral catheter into the upper urinary tract is unusual, and only a few cases have been reported. We describe the case of a 43-year-old man who presented with oliguria and had a history of chemotherapy for known metastatic lung cancer. As he had no history of urological disease, urethral catheterization was expected to be uneventful. The catheter was unable to be pulled back to the bladder neck once the balloon was inflated, and the patient expressed discomfort. Subsequent computed tomography revealed that the tip of the catheter was placed in the middle of the right ureter. Unbeknownst to the physicians before urethral catheterization, the patient had severe lower urinary tract symptoms and urinary bladder dysfunction with hydronephrosis, likely due to chemotherapy. Based on the patient’s symptoms and imaging results, we judged the possibility of severe ureteral injury to be low. The malpositioned catheter was removed uneventfully after complete balloon deflation and then reinserted properly. He was admitted to the medical department but died as a result of an exacerbation of the underlying disease unrelated to the incident. If urethral catheter placement seems abnormal, physicians should aspirate and irrigate to confirm correct positioning before balloon inflation; then, they should carefully pull the inflated balloon near the neck of the bladder while monitoring the patient’s symptoms. Although urethral catheter placement is comparatively safe, physicians must keep in mind that patients who have undergone chemotherapy might be at a risk for this rare complication. 相似文献