全文获取类型
收费全文 | 58505篇 |
免费 | 5433篇 |
国内免费 | 4212篇 |
专业分类
耳鼻咽喉 | 646篇 |
儿科学 | 599篇 |
妇产科学 | 564篇 |
基础医学 | 6000篇 |
口腔科学 | 872篇 |
临床医学 | 7461篇 |
内科学 | 7943篇 |
皮肤病学 | 569篇 |
神经病学 | 2778篇 |
特种医学 | 2279篇 |
外国民族医学 | 36篇 |
外科学 | 6350篇 |
综合类 | 10803篇 |
现状与发展 | 13篇 |
一般理论 | 3篇 |
预防医学 | 4148篇 |
眼科学 | 1623篇 |
药学 | 6401篇 |
53篇 | |
中国医学 | 4130篇 |
肿瘤学 | 4879篇 |
出版年
2024年 | 251篇 |
2023年 | 854篇 |
2022年 | 2309篇 |
2021年 | 2931篇 |
2020年 | 2391篇 |
2019年 | 1859篇 |
2018年 | 2007篇 |
2017年 | 1993篇 |
2016年 | 1796篇 |
2015年 | 2879篇 |
2014年 | 3611篇 |
2013年 | 3325篇 |
2012年 | 4835篇 |
2011年 | 5179篇 |
2010年 | 3591篇 |
2009年 | 2910篇 |
2008年 | 3370篇 |
2007年 | 3167篇 |
2006年 | 3045篇 |
2005年 | 2813篇 |
2004年 | 1834篇 |
2003年 | 1736篇 |
2002年 | 1439篇 |
2001年 | 1192篇 |
2000年 | 1118篇 |
1999年 | 1055篇 |
1998年 | 657篇 |
1997年 | 596篇 |
1996年 | 492篇 |
1995年 | 456篇 |
1994年 | 347篇 |
1993年 | 266篇 |
1992年 | 319篇 |
1991年 | 313篇 |
1990年 | 214篇 |
1989年 | 169篇 |
1988年 | 196篇 |
1987年 | 154篇 |
1986年 | 101篇 |
1985年 | 80篇 |
1984年 | 60篇 |
1983年 | 32篇 |
1982年 | 29篇 |
1981年 | 31篇 |
1980年 | 23篇 |
1979年 | 38篇 |
1978年 | 13篇 |
1977年 | 11篇 |
1975年 | 11篇 |
1973年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
目的 总结冠状动脉旁路移植术治疗冠心病的体会。 方法 回顾性分析 3 0 6例冠状动脉旁路移植术。男 2 49例 ,女 5 7例。应用体外循环 2 3 4例 ,非体外循环 72例。搭桥数 1~ 6支 人 ,平均 (3 .45± 1.2 5 )支 人。对手术方法、主要并发症和术后处理进行分析总结。结果 二次开胸 5例 (1.6% ) ,低心排综合征 10例 (3 .3 % ) ,应用IABP4例 (1.3 % ) ,肝功能不全 6例 (2 .0 % )。肾功能不全 7例 (2 .3 % ) ,反复发作房颤 2 3例 (7.5 % ) ,肺功能不全 6例(2 .0 % ) ,脑合并症 3例 (1.0 % ) ,胸腔积液 41例 (13 .4% )。死亡 7例 (2 .3 % ) ,其余病人康复出院。结论 合理的选择病人 ,成熟的手术技术 ,良好的心肌保护及术后处理的加强是提高冠状动脉旁路移植术疗效的重要措施。 相似文献
102.
第一极体不能精确定位人卵母细胞纺锤体 总被引:4,自引:0,他引:4
目的 观测人卵母细胞纺锤体的确切位置,从而指导今后的生殖医学临床工作。方法 应用纺锤体成像系统观测体外成熟及体内成熟组人卵母细胞纺锤体,测量卵子中心、纺锤体与第一极体之间形成的角度。比较两组结果的差异。结果 体外成熟组纺锤体与第一极体形成角度和体内成熟组存在显著差异(P=0.006)。结论 人卵母细胞的位置并不能准确定位卵母细胞纺锤体的位置。体外成熟组纺锤体与第一极体形成的角度要明显小于体内成熟组。应用纺锤体成像系统可以安全、有效地观察人卵母细胞纺锤体。 相似文献
103.
目的:通过对颅脑损伤所致器质性人格改变的患者进行量化评估分析,以寻找一种最适合颅脑损伤后人格改变的量化评估方法。方法:全部病例来自2003-01-03/2005-01-31期间到深圳市康宁医院法医精神病司法鉴定所进行工伤鉴定的工伤所致颅脑损伤患者116例,所有病例首先由综合医院神经外科行头颅CT或MRI检查,并对颅脑损伤的部位、性质、严重程度等做出诊断和治疗。治疗终结后,由两名副高级主任医师及以上职称的精神医学鉴定专家对患者的精神状况进行评估,并分别做出有无人格改变的诊断。同时采用慢性脑器质性人格改变评定量表(包括10个条目)及自编脑外伤后人格改变评定量表(包括5个因子17个条目)对患者人格改变的情况进行量化评定。以专家诊断结果为效标,对两种量表对颅脑损伤所致人格改变的判定灵敏度和特异性以及两量表的内部条目进行分析。结果:①颅脑损伤所致人格改变专家评定及量表评定结果:经专家鉴定,116例颅脑损伤患者中诊断为颅脑损伤所致器质性人格改变的患者22例,占所有调查对象的19%,评估者的诊断一致性kappa值为0.86(P<0.01)。以专家诊断为效标,慢性脑器质性人格改变评定量表对本组颅脑损伤患者所致人格改变诊断的假阳性率为0,假阴性率为50%;自编脑外伤后人格改变评定量表的假阳性率为2.4%,假阴性率为4.5%。②两种量表评定颅脑损伤所致人格改变的内部条目分析:慢性脑器质性人格改变评定量表各条目评分结果显示有人格改变与无人格改变的患者在情绪不稳、情感淡漠或不协调、社会功能减退、个性改变、行为障碍5个条目的差异显著(t=2.082~5.921,P<0.01~0.05)。自编脑外伤后人格改变评定量表除认知偏离因子中的所有条目外,情感偏离因子中的情绪不稳,情感脆弱,易激惹,情感平淡、不关心人4个条目,意志行为偏离中的意志缺乏,欲望增强,行为冲动、不计后果,自我中心4个条目,人际关系偏离及原有人格变化及其所有条目上均有显著性差异(t=13.339~2.094,P<0.01~0.05)。结论:自编脑外伤后人格改变评定量表提高了对颅脑损伤所致人格改变诊断的灵敏度,其各条目能更准确地反映颅脑损伤所致人格改变的临床特点,但其信度和效度还需进一步完善。 相似文献
104.
人工食管植入术后影像学检查的实验研究 总被引:5,自引:0,他引:5
目的 探讨影像学检查方法在人工食管实验研究中的应用价值。方法 对10只植入胸段记忆合金组合式人工食管的实验动物模型术后所进行X线平片和食管造影检查结果进行观察分析研究。结果 X线平片清晰显示胸内植入记忆合金组合式人工食管植入的位置原位固定〉9个月3只;2—3月内脱管3只;〉3个月内脱管4只;管体全部滑至胃内,食管造影连续摄片显示重度新生食管狭窄3只;轻度新生食管狭窄4只,同期介入安放食管支架2只.全组仅见1只发生吻合口细小瘘。无发现其它胸内并发症。结论 ①X线检查是进行人工食管动物实验研究简单且实用的检查方法.②食管造影连续摄片检查方法可为已建立植入人工食管的猪实验动物模型术后的观察研究及介入治疗提供多方面的支持帮助。 相似文献
105.
以猪作为动物模型,通过分层抽样,制作各向同性切片,在图像分析仪下对超薄皮瓣的血管密度进行了观察。结果表明:超薄皮瓣血管密度于术后第5天开始出现显著性变化。这种变化首先出现在超薄皮瓣存活部分的远端,之后渐至近端。这种变化在超薄皮瓣血运重建过程中起主要作用。 相似文献
106.
超声引导下肿瘤内注射^90钇玻璃微球的肝癌综合治疗 总被引:12,自引:0,他引:12
超声引导下对28例肝癌病人进行了肿瘤内注射^90钇玻璃微球(Y-90GT MS)为主的综合性治疗(部分病人配合肿块周边注射无水酒精及门静脉穿刺化疗)。随访2~16个月(平均7.9个月),病人全健在。肿瘤缩小率为91%,其中显著缩小达75%;肿块回声呈致密增强,少数呈混合型或等回声型;肿瘤内及周边血流信号显著减少;原甲胎蛋白升高者13例,11例显著下降,其中6例降至正常;病人症状减轻,全身情况改善。 相似文献
107.
Kevin M Kernek Matteo Brunelli Thomas M Ulbright John N Eble Guido Martignoni Shaobo Zhang Helen Michael Oscar W Cummings Liang Cheng 《Modern pathology》2004,17(11):1309-1313
The over-representation of chromosome 12p sequences is crucial for the development of invasive testicular germ cell tumors. Testicular cancer patients may have metastatic tumors of diverse histologic types, including adenocarcinoma, undifferentiated carcinoma, sarcoma, or other malignancies that lack features of germ cell tumors. We sought to investigate the possible germ cell origin of such tumors using interphase fluorescence in situ hybridization. In all, 10 metastatic malignant somatic-type tumors from patients with histories of testicular cancer, as well as one malignant somatic-type tumor from a patient with primary mediastinal germ cell tumor were studied and included: adenocarcinoma (five cases), poorly differentiated carcinoma (one), sarcoma (four), and neuroendocrine carcinoma (one). The tumors were analyzed using fluorescence in situ hybridization using 12p spectrum green and 12 centromeric spectrum orange probes in paraffin sections. The patients ranged in age from 27 to 55 years (mean, 43). Colon and lung cancers from patients without germ cell tumors were used as controls. Adequate signals were observed in all tumors. Gain of chromosome 12p was seen in six tumors. None of the control tumors showed 12p amplification. Fluorescence in situ hybridization for 12p amplification in routinely processed surgical specimens is a useful adjuvant diagnostic tool in confirming the germ cell origin of metastatic tumors having the histologic appearance of somatic-type neoplasms. 相似文献
108.
同类药物因原料来源、附加成分和生产厂家不同而商品名称各异,有些名称相似的药物其性能却完全不同。临床实习护生常反映课本讲授的药物知识与临床用药相差甚远,不知如何记住所有的药物。为此,作者在临床教学中培养学生养成阅读药物说明书的习惯,收到良好效果。 相似文献
109.
Tom C Nguyen Allen Cheng Frederick A Tibayan David Liang George T Daughters Neil B Ingels David Craig Miller 《European journal of cardio-thoracic surgery》2007,31(3):423-429
OBJECTIVE: Septal-lateral annular cinching ('SLAC') corrects both acute and chronic ischemic mitral regurgitation in animal experiments, which has led to the development of therapeutic surgical and interventional strategies incorporating this concept (e.g., Edwards GeoForm ring, Myocor Coapsys, Ample Medical PS3). Changes in left ventricular (LV) transmural cardiac and fiber-sheet strains after SLAC, however, remain unknown. METHODS: Eight normal sheep hearts had two triads of transmural radiopaque bead columns inserted adjacent to (anterobasal) and remote from (midlateral equatorial) the mitral annulus. Under acute, open chest conditions, 4D bead coordinates were obtained using videofluoroscopy before and after SLAC. Transmural systolic strains were calculated from bead displacements relative to local circumferential, longitudinal, and radial cardiac axes. Transmural cardiac strains were transformed into fiber-sheet coordinates (X(f), X(s), X(n)) oriented along the fiber (f), sheet (s), and sheet-normal (n) axes using fiber (alpha) and sheet (beta) angle measurements. Results: SLAC markedly reduced (approximately 60%) septal-lateral annular diameter at both end-diastole (ED) (2.5+/-0.3 to 1.0+/-0.3 cm, p=0.001) and end-systole (ES) (2.4+/-0.4 to 1.0+/-0.3 cm, p=0.001). In the LV wall remote from the mitral annulus, transmural systolic strains did not change. In the anterobasal region adjacent to the mitral annulus, ED wall thickness increased (p=0.01) and systolic wall thickening was less in the epicardial (0.28+/-0.12 vs 0.20+/-0.06, p=0.05) and midwall (0.36+/-0.24 vs 0.19+/-0.11, p=0.04) LV layers. This impaired wall thickening was due to decreased systolic sheet thickening (0.20+/-0.8 to 0.12+/-0.07, p=0.01) and sheet shear (-0.15+/-0.07 to -0.11+/-0.04, p=0.02) in the epicardium and sheet extension (0.21+/-0.11 to 0.10+/-0.04, p=0.03) in the midwall. Transmural systolic and remodeling strains in the lateral midwall (remote from the annulus) were unaffected. CONCLUSIONS: Although SLAC is an alluring concept to correct ischemic mitral regurgitation, these data suggest that extreme SLAC adversely effects systolic wall thickening adjacent to the mitral annulus by inhibiting systolic sheet thickening, sheet shear, and sheet extension. Such alterations in LV strains could result in unanticipated deleterious remodeling and warrant further investigation. 相似文献
110.
Shang Wen Chen Ji An Liang Shih Neng Yang Hui Ling Ko Fang Jen Lin 《Radiotherapy and oncology》2003,67(1):69-76
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups. 相似文献