全文获取类型
收费全文 | 1007篇 |
免费 | 59篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 111篇 |
妇产科学 | 50篇 |
基础医学 | 137篇 |
口腔科学 | 21篇 |
临床医学 | 57篇 |
内科学 | 235篇 |
皮肤病学 | 6篇 |
神经病学 | 77篇 |
特种医学 | 46篇 |
外科学 | 73篇 |
综合类 | 12篇 |
预防医学 | 79篇 |
眼科学 | 8篇 |
药学 | 64篇 |
中国医学 | 3篇 |
肿瘤学 | 85篇 |
出版年
2024年 | 2篇 |
2023年 | 16篇 |
2022年 | 32篇 |
2021年 | 36篇 |
2020年 | 25篇 |
2019年 | 34篇 |
2018年 | 43篇 |
2017年 | 23篇 |
2016年 | 45篇 |
2015年 | 47篇 |
2014年 | 60篇 |
2013年 | 62篇 |
2012年 | 102篇 |
2011年 | 72篇 |
2010年 | 42篇 |
2009年 | 36篇 |
2008年 | 57篇 |
2007年 | 73篇 |
2006年 | 46篇 |
2005年 | 52篇 |
2004年 | 42篇 |
2003年 | 33篇 |
2002年 | 38篇 |
2001年 | 10篇 |
2000年 | 1篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有1068条查询结果,搜索用时 15 毫秒
71.
72.
73.
Kim CJ Kaplan LE Perwad F Huang N Sharma A Choi Y Miller WL Portale AA 《The Journal of clinical endocrinology and metabolism》2007,92(8):3177-3182
CONTEXT: Vitamin D 1alpha-hydroxylase deficiency, also known as vitamin D-dependent rickets type 1, is an autosomal recessive disorder characterized by the early onset of rickets with hypocalcemia and is caused by mutations of the 25-hydroxyvitamin D 1alpha-hydroxylase (1alpha-hydroxylase, CYP27B1) gene. The human gene encoding the 1alpha-hydroxylase is 5 kb in length, located on chromosome 12, and comprises nine exons and eight introns. We previously isolated the human 1alpha-hydroxylase cDNA and gene and identified 19 different mutations in 25 patients with 1alpha-hydroxylase deficiency. OBJECTIVES, PATIENTS, AND METHODS: We analyzed the 1alpha-hydroxylase gene of 10 patients, five from Korea, two from the United States, and one each from Argentina, Denmark, and Morocco, all from nonconsanguineous families. Each had clinical and radiographic features of rickets, hypocalcemia, and low serum concentrations of 1,25-dihydroxyvitamin D(3). RESULTS: Direct sequencing identified the responsible 1alpha-hydroxylase gene mutations in 19 of 20 alleles. Four novel and four known mutations were identified. The new mutations included a nonsense mutation in exon 6, substitution of adenine for guanine (2561G-->A) creating a stop signal at codon 328; deletion of adenine in exon 9 (3922delA) causing a frameshift; substitution of thymine for cytosine in exon 2 (1031C-->T) causing the amino acid change P112L; and a splice site mutation, substitution of adenine for guanine in the first nucleotide of intron 7 (IVS7+1 G-->A) causing a frameshift. CONCLUSIONS: Mutations in the 1alpha-hydroxylase gene previously were identified in 44 patients, to which we add 10 more. The studies show a strong correlation between 1alpha-hydroxylase mutations and the clinical findings of 1alpha-hydroxylase deficiency. 相似文献
74.
Abikoff HB Vitiello B Riddle MA Cunningham C Greenhill LL Swanson JM Chuang SZ Davies M Kastelic E Wigal SB Evans L Ghuman JK Kollins SH McCracken JT McGough JJ Murray DW Posner K Skrobala AM Wigal T 《Journal of child and adolescent psychopharmacology》2007,17(5):581-592
OBJECTIVE: The purpose of this study was to examine the effects of methylphenidate (MPH) on functional outcomes, including children's social skills, classroom behavior, emotional status, and parenting stress, during the 4-week, double-blind placebo controlled phase of the Preschoolers with Attention Deficit/Hyperactivity Disorder (ADHD) Treatment Study (PATS). METHODS: A total of 114 preschoolers who had improved with acute MPH treatment, were randomized to their best MPH dose (M = 14.22 mg/day; n = 63) or placebo (PL; n = 51). Assessments included the Clinical Global Impression-Severity (CGI-S), parent and teacher versions of the Strengths and Weaknesses of ADHD-Symptoms and Normal Behaviors (SWAN), Social Competence Scale (SCS), Social Skills Rating System (SSRS), and Early Childhood Inventory (ECI), and Parenting Stress Index (PSI). RESULTS: Medication effects varied by informant and outcome measure. Parent measures and teacher SWAN scores did not differentially improve with MPH. Parent-rated depression (p < 0.02) and dysthymia (p < 0.001) on the ECI worsened with MPH, but scores were not in the clinical range. Significant medication effects were found on clinician CGI-S (p < 0.0001) and teacher social competence ratings (SCS, p < 0.03). CONCLUSIONS: Preschoolers with ADHD treated with MPH for 4 weeks improve in some aspects of functioning. Additional improvements might require longer treatment, higher doses, and/or intensive behavioral treatment in combination with medication. 相似文献
75.
Murray DW Kollins SH Hardy KK Abikoff HB Swanson JM Cunningham C Vitiello B Riddle MA Davies M Greenhill LL McCracken JT McGough JJ Posner K Skrobala AM Wigal T Wigal SB Ghuman JK Chuang SZ 《Journal of child and adolescent psychopharmacology》2007,17(5):605-620
OBJECTIVE: To assess parent-teacher concordance on ratings of DSM-IV symptoms of attention-deficit/hyperactivity disorder (ADHD) in a sample of preschool children referred for an ADHD treatment study. METHODS: Parent and teacher symptom ratings were compared for 452 children aged 3-5 years. Agreement was calculated using Pearson correlations, Cohen's kappa, and conditional probabilities. RESULTS: The correlations between parent and teacher ratings were low for both Inattentive (r = .24) and Hyperactive-Impulsive (r = .26) symptom domains, with individual symptoms ranging from .01-.28. Kappa values for specific symptoms were even lower. Conditional probabilities suggest that teachers are only moderately likely to agree with parents on the presence or absence of symptoms. Parents were quite likely to agree with teachers' endorsement of symptoms, but much less likely to agree when teachers indicated that a symptom was not present. CONCLUSIONS: Results provide important data regarding base rates and concordance rates in this age group and support the hypothesis that preschool-aged children at risk for ADHD exhibit significant differences in behavior patterns across settings. Obtaining ratings from multiple informants is therefore considered critical for obtaining a full picture of young children's functioning. 相似文献
76.
77.
78.
Rare cases of intracranial chondromas have been documented in the literature, often after complete surgical excision. We describe a case of giant intracranial tumor at post‐mortem examination of a man who had survived 48 years after a partial debulking. Histological examination revealed a chondroid tumor with no significant pleomorphism and central cystic degeneration. Our case illustrates the benignity of the intracranial chondroma and to our knowledge, is one of the longest surviving and largest cases found after incomplete removal. 相似文献
79.
80.