全文获取类型
收费全文 | 217922篇 |
免费 | 28984篇 |
国内免费 | 7640篇 |
专业分类
耳鼻咽喉 | 1710篇 |
儿科学 | 1698篇 |
妇产科学 | 5169篇 |
基础医学 | 15706篇 |
口腔科学 | 2187篇 |
临床医学 | 17554篇 |
内科学 | 22650篇 |
皮肤病学 | 1378篇 |
神经病学 | 1228篇 |
特种医学 | 6254篇 |
外国民族医学 | 270篇 |
外科学 | 30790篇 |
综合类 | 28661篇 |
现状与发展 | 39篇 |
一般理论 | 3篇 |
预防医学 | 10478篇 |
眼科学 | 122篇 |
药学 | 15497篇 |
147篇 | |
中国医学 | 5703篇 |
肿瘤学 | 87302篇 |
出版年
2024年 | 725篇 |
2023年 | 4581篇 |
2022年 | 8940篇 |
2021年 | 11618篇 |
2020年 | 10846篇 |
2019年 | 9726篇 |
2018年 | 9326篇 |
2017年 | 9822篇 |
2016年 | 10561篇 |
2015年 | 12235篇 |
2014年 | 17562篇 |
2013年 | 17592篇 |
2012年 | 14065篇 |
2011年 | 14322篇 |
2010年 | 10445篇 |
2009年 | 10621篇 |
2008年 | 10968篇 |
2007年 | 10419篇 |
2006年 | 9119篇 |
2005年 | 7536篇 |
2004年 | 6238篇 |
2003年 | 5197篇 |
2002年 | 4444篇 |
2001年 | 4117篇 |
2000年 | 3501篇 |
1999年 | 2925篇 |
1998年 | 2465篇 |
1997年 | 2174篇 |
1996年 | 1806篇 |
1995年 | 1727篇 |
1994年 | 1437篇 |
1993年 | 1090篇 |
1992年 | 947篇 |
1991年 | 886篇 |
1990年 | 670篇 |
1989年 | 616篇 |
1988年 | 522篇 |
1987年 | 434篇 |
1986年 | 311篇 |
1985年 | 401篇 |
1984年 | 343篇 |
1983年 | 220篇 |
1982年 | 227篇 |
1981年 | 206篇 |
1980年 | 186篇 |
1979年 | 123篇 |
1978年 | 82篇 |
1977年 | 74篇 |
1976年 | 65篇 |
1975年 | 41篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
IL—6转基因表达诱导大肠癌细胞凋亡 总被引:4,自引:0,他引:4
通过分子克隆技术将IL-6基因导入大肠癌细胞HT-29,建立了目的基因转导株HT-29IL-6细胞,该转导株接种子裸鼠皮下后,与非转导株相比,长出肿瘤的时间延后,最终瘤径明显较小,而且移植瘤标本镜下可见大量的核固缩,核染色质加深,核断裂等凋亡细胞,用携带IL-6基因的重组逆转病毒液感染大肠癌细胞Lovo后,仅以1.25μmol/L的VUMON-26(简称VM-26)即可诱导该转染株发生明显凋亡,而 相似文献
942.
肺癌的治疗方案与预后取决于肺癌的病理类型。本文按照概率型的数学模型──最大似然法,建立计算机鉴别肺癌病理类型的数学模型,用BASIC语言编制诊断程序。结果表明该方法的诊断正确率高于临床,为肺癌病理类型的分类提供了一种简便、快捷、实用的方法。 相似文献
943.
肿瘤抗原冲击致敏的IL-2基因修饰的巨噬细胞治疗肾癌的实验研究 总被引:1,自引:0,他引:1
目的 :观察体外肿瘤抗原冲击致敏的白细胞介素 2 (IL 2 )基因修饰的巨噬细胞对肾癌小鼠的治疗效果并探讨其相关的免疫机理。方法 :通过重组腺病毒的介导 ,将IL 2基因转入新鲜分离的小鼠腹腔巨噬细胞 ,经肿瘤抗原冲击致敏后回输治疗原位肾癌小鼠 ,采用 4h5 1 Cr释放法检测脾脏NK和CTL活性。结果 :IL 2基因修饰的巨噬细胞经肿瘤抗原冲击后体内回输可使肾癌小鼠肺转移结节明显减少 ,存活期明显延长 ,40 %肾癌小鼠达到长期存活。治疗后荷瘤小鼠脾脏NK和CTL活性显著提高。结论 :IL 2基因修饰的巨噬细胞经肿瘤抗原冲击后自体回输是治疗肾癌的有效方法。 相似文献
944.
945.
Dahlquist Lynnda M.; Czyzewski Danita I.; Jones Cheri L. 《Journal of pediatric psychology》1996,21(4):541-554
Evaluated emotional distress, coping style, and marital adjustmentin 84 parents (42 couples) of children with cancer 2 monthsafter diagnosis and again about 20 months after diagnosis. Asexpected, mothers' mean state anxiety and trait anxiety scoresdecreased to near normal levels over time. Fathers' scores werelower initially and did not change. Neither mothers' nor fathers'mean marital adjustment scores changed over time. Marital adjustmentat treatment follow-up was predicted by depression and the spouse'smarital satisfaction in mothers, and depression, child healthstatus, and spouse's marital satisfaction in fathers. In contrastto findings obtained 2 months after diagnosis, coping stylewas not related to marital adjustment at follow-up. Resultsare discussed in terms of possible gender differences in therole of social support in marital adjustment and the stabilityversus situational specificity of coping styles. 相似文献
946.
原发性肝癌患者手术前后血清SICAM-1、VEGF水平检测的临床意义 总被引:1,自引:0,他引:1
目的:分析了31例原发性肝癌患者手术前后血清SICAM-1、VEGF水平的变化。方法:采用双抗 体夹心法测定了31例原发性肝癌患者手术前后血清SICAM-1、VEGF含量,并与35名正常人作比较。结果: 手术前血清SICAM-1、VEGF水平非常显著地高于正常人组(P<0.01),手术后6个月,复发者SICAM-1、 VEGF水平持续异常,未复发者SICAM-1、VEGF水平恢复正常。结论:观察原发性肝癌患者血清SICAM-1 和VEGF水平的变化与原发性肝癌患者的病情和预后密切相关。 相似文献
947.
The Perception of Procedures Questionnaire: Psychometric Properties of a Brief Parent Report Measure of Procedural Distress 总被引:1,自引:3,他引:1
Kazak Anne E.; Penati Biancamaria; Waibel Mary Katherine; Blackall George F. 《Journal of pediatric psychology》1996,21(2):195-207
Reported the reliability and validity of the Perception of ProceduresQuestionnaire (PPQ), a 19-item parent-report measure developedto assess child and parent distress related to lumbar puncturesand bone marrow aspirates in the diagnosis and treatment ofchildhood cancer. PPQ data from 140 mothers and 96 fathers ofchildren and adolescents with leukemia in a first remissionwere analyzed separately. Factor analyses yielded five factorsfor mothers and fathers: Parent Satisfaction; Child Distress:During; Child Distress: Before; Parent Distress; and ParentInvolvement. Internal consistency (Cronbach's alpha) was highfor the total score and the five factor scores as were interraterreliabilities between mothers and fathers. Validity was determinedusing the Parenting Stress Index-Short Form, the Pediatric OncologyQuality of Life Scale, and parent and nurse ratings during procedures.Factors 2 and 3, assessing child distress, show strong associationswith the validation measures and support the distinction betweendistress before and during procedures. This developing scaleis recommended for use in the assessment and evaluation of childand parent procedure-related distress in pediatric oncology. 相似文献
948.
949.
pathological prognostic factors in breast cancer. I. The value of histological grade in breast cancer: experience from a large study with long-term follow-up 总被引:45,自引:0,他引:45
Morphological assessment of the degree of differentiation has been shown in numerous studies to provide useful prognostic information in breast cancer, but until recently histological grading has not been accepted as a routine procedure, mainly because of perceived problems with reproducibility and consistency. In the Nottingham/Tenovus Primary Breast Cancer Study the most commonly used method, described by Bloom & Richardson, has been modified in order to make the criteria more objective. The revised technique involves semiquantitative evaluation of three morphological features--the percentage of tubule formation, the degree of nuclear pleomorphism and an accurate mitotic count using a defined field area. A numerical scoring system is used and the overall grade is derived from a summation of individual scores for the three variables: three grades of differentiation are used. Since 1973, over 2200 patients with primary operable breast cancer have been entered into a study of multiple prognostic factors. Histological grade, assessed in 1831 patients, shows a very strong correlation with prognosis; patients with grade I tumours have a significantly better survival than those with grade II and III tumours (P less than 0.0001). These results demonstrate that this method for histological grading provides important prognostic information and, if the grading protocol is followed consistently, reproducible results can be obtained. Histological grade forms part of the multifactorial Nottingham prognostic index, together with tumour size and lymph node stage, which is used to stratify individual patients for appropriate therapy. 相似文献
950.
Antoine C Liebens F Carly B Pastijn A Rozenberg S;Women's Health Initiative 《Human reproduction (Oxford, England)》2004,19(3):741-756
INTRODUCTION: Mortality due to breast cancer has been reported to be the same or even lower in HRT users than in non-users. This has been attributed to earlier diagnosis and to better prognosis. Nevertheless, more advanced disease in HRT users was reported recently by the Women's Health Initiative (WHI) study. The objective of this study was to assess, using a systematic review of current literature, whether the data of the WHI study are in contradiction to observational data. METHODS: We selected 25 studies, for which we evaluated the methodology, the characteristics of the studied populations, confounding breast cancer risk factors and prognostic indicators. RESULTS: The WHI study, showing a worsening of some prognostic parameters, is in contradiction to most published observational studies. Most observational studies are retrospective, not well matched and did not consider most confounding factors. Their methodology and selection criteria varied considerably and the number of patients was often small. No differences in the distributions of histology, grade or steroid receptors were observed in the WHI trial, while this was the case in some of the observational studies. Other parameters (S phase, protein Neu, Bcl-2 gene, protein p53 and E-cadherin, cathepsin D) were not reported in the WHI trial. CONCLUSIONS: In view of these data, the current clinical message to patients should be changed: one can no longer declare that breast cancers developed while using HRT are of better prognosis. 相似文献