全文获取类型
收费全文 | 139682篇 |
免费 | 12000篇 |
国内免费 | 6708篇 |
专业分类
耳鼻咽喉 | 1316篇 |
儿科学 | 2117篇 |
妇产科学 | 3072篇 |
基础医学 | 15211篇 |
口腔科学 | 2880篇 |
临床医学 | 16987篇 |
内科学 | 22492篇 |
皮肤病学 | 1759篇 |
神经病学 | 7475篇 |
特种医学 | 4636篇 |
外国民族医学 | 40篇 |
外科学 | 14976篇 |
综合类 | 19440篇 |
现状与发展 | 21篇 |
一般理论 | 23篇 |
预防医学 | 10058篇 |
眼科学 | 3761篇 |
药学 | 14232篇 |
115篇 | |
中国医学 | 6590篇 |
肿瘤学 | 11189篇 |
出版年
2024年 | 352篇 |
2023年 | 1795篇 |
2022年 | 4291篇 |
2021年 | 5896篇 |
2020年 | 4276篇 |
2019年 | 3944篇 |
2018年 | 4285篇 |
2017年 | 3924篇 |
2016年 | 3577篇 |
2015年 | 5582篇 |
2014年 | 7159篇 |
2013年 | 7476篇 |
2012年 | 10921篇 |
2011年 | 11762篇 |
2010年 | 7949篇 |
2009年 | 6588篇 |
2008年 | 8482篇 |
2007年 | 8408篇 |
2006年 | 7955篇 |
2005年 | 7334篇 |
2004年 | 5395篇 |
2003年 | 4926篇 |
2002年 | 4134篇 |
2001年 | 3159篇 |
2000年 | 2898篇 |
1999年 | 2715篇 |
1998年 | 1405篇 |
1997年 | 1305篇 |
1996年 | 1045篇 |
1995年 | 1001篇 |
1994年 | 945篇 |
1993年 | 553篇 |
1992年 | 919篇 |
1991年 | 835篇 |
1990年 | 699篇 |
1989年 | 596篇 |
1988年 | 553篇 |
1987年 | 472篇 |
1986年 | 380篇 |
1985年 | 310篇 |
1984年 | 217篇 |
1983年 | 203篇 |
1982年 | 141篇 |
1981年 | 136篇 |
1980年 | 116篇 |
1979年 | 175篇 |
1978年 | 144篇 |
1977年 | 116篇 |
1974年 | 119篇 |
1972年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Eighteen healthy adult volunteers completed an open-label, four-way crossover study designed to determine the bioequivalency of 160-mg cibenzoline [2-(2,2-diphenylcyclopropyl)-4,5-dihydro-1H-imidazole] capsules and tablets, their relative bioavailability compared with an oral solution of the drug, as well as the absolute bioavailability of these dosage forms compared with an intravenous infusion of the drug. Blood samples obtained at specified times after drug administration were assayed for cibenzoline by HPLC, and pharmacokinetic parameters were estimated from the resulting plasma concentration-time profiles. Comparisons were made between the tablet and capsule to assess bioequivalency, between the solid dosage forms and a solution to assess relative bioavailability, and between the oral forms and an intravenous infusion to assess absolute bioavailability. The pharmacokinetic parameters for each oral dosage form were similar and ratios of mean parameters indicated that the solid dosage forms were bioequivalent and completely bioavailable relative to an oral solution. The ratios of the area under the plasma concentration-time profiles (AUC) for the capsule, tablet, and oral solution to that of the intravenous infusion were 0.85, 0.83, and 0.86, respectively, indicating that orally administered cibenzoline has an absolute bioavailability of approximately 85%. 相似文献
92.
Metastatic septic endophthalmitis in pyogenic liver abscess 总被引:4,自引:0,他引:4
In a consecutive series of 180 patients with pyogenic liver abscess, three patients (two men and one woman, between 46 and 75 years of age) had metastatic Klebsiella endophthalmitis. The incidence of metastatic endophthalmitis was 1.7% in patients with pyogenic liver abscess, 5.2% in patients with Klebsiella liver abscess, and 7.8% in patients with Klebsiella liver abscess having Klebsiella bacteremia. Despite aggressive therapeutic measures, the men permanently lost their vision and the woman eventually required an evisceration of her right eye. Delayed recognition and/or treatment as well as the nature of bacteria probably contributed to the tragic outcome. The findings suggest that a high index of suspicion is critical and a combined effort of the internist and ophthalmologist is mandatory. 相似文献
93.
Brian F Perry Ivan S Login Stilianos E Kountakis 《Otolaryngology--head and neck surgery》2004,130(4):449-452
OBJECTIVE: Our goal was to determine the etiology of headache in patients who were referred for sinus evaluation but were found to have no evidence of rhinosinusitis on computed tomography (CT) of the sinuses and on endoscopic examination. METHODS: Data were collected prospectively from 100 patients with headache but with normal sinus CT and endoscopic examination. Headache and 20-Item Sino-Nasal Outcomes Test (SNOT-20) scores of patients with the chief complaint of headache and who requested further neurologic evaluation (group I) were compared with the scores of patients who did not list headache as a significant symptom (group II) and with the scores of patients without headache (group III). RESULTS: The most common neurologic diagnosis for group I patients (n = 36) was migraine headaches (58%). These patients also had higher mean SNOT-20 scores (24 +/- 3.3) compared to group II patients with mild headache (14.6 +/- 2.3) or group III patients without headache (12.4 +/- 2.1). CONCLUSION: Migraine was the most common type of headache in patients with normal sinus CT treated for presumed rhinosinusitis as the cause of the headache. Patients with headache as their chief complaint that required further neurologic evaluation had overall higher SNOT-20 scores than nonheadache patients, indicating greater disability of their overall quality of life index. 相似文献
94.
Chih-Ming Lin Pei-Chen Lee Sen-Wen Teng Tsung-Hsueh Lu I-Fang Mao Chung-Yi Li 《台湾医志》2004,103(4):297-301
BACKGROUND AND PURPOSE: Birth certificates are a major source of population-based data often used in maternal and child health research, but their value depends upon the level of accuracy of the data. The purpose of this study was to assess the validity of the birth registry data in Taiwan. METHODS: Obstetric records of a total of 2779 infants born at a municipal hospital in Taipei between 1995 and 1997 were abstracted and linked to the Taiwan Birth Registry (TBR). Concordance was presented by agreement percentages for various birth characteristics including gender, birth order, birth weight, and gestational age. Concordance was further assessed using Cohen's k and sensitivity/specificity for both birth weight and gestational age, with both variables categorized according to their customary definitions. RESULTS: Missing data for specific items in the TBR ranged from 0% (gender) to 1.6% (birth order). The birth registry accurately reported all 4 selected items, with the highest and lowest concordance percentage noted for gender (99.0%) and gestational age (88.3%), respectively. The level of agreement indicated by the Cohen's k statistic ranged from 0.92 to 0.96 for birth weight and gestational age when both variables were treated as categorical variables. CONCLUSIONS: The TBR showed a low rate of missing information and high levels of validity for the elements frequently used in maternal and child health research in Taiwan. 相似文献
95.
异氟醚控制性降压对颅内动脉瘤夹闭术血中S100B含量的影响 总被引:3,自引:1,他引:2
目的 测定颅内动脉瘤夹闭前后血中S1 0 0B蛋白含量 ,研究异氟醚控制性降压对脑功能的影响。方法 择期颅内动脉瘤夹闭术病人 30例 ,ASAⅠ~Ⅱ级 ,随机分为两组 :异氟醚降压组 (n=1 5 )和异氟醚非降压组 (n =1 5 )。非降压组术中吸入 1MAC异氟醚维持麻醉。降压组行异氟醚控制性降压 ,平均动脉压下降幅度 30 %~ 4 0 % ,夹闭动脉瘤后降低异氟醚吸入浓度 ,终止降压。分别于切皮前、动脉瘤夹闭后即刻、2、4h、术后第 1、2天取血测定S1 0 0B蛋白含量 ,并于术后 1周随访病人 ,记录有无术后神经系统并发症。结果 (1 )异氟醚降压后 30min平均动脉压由诱导前的 (95 2± 1 2 3)mmHg降至 (5 8 8± 5 4 )mmHg ,停止降压后 30min血压回升至 (75 1± 8 3)mmHg。降压后外周血管阻力及心肌收缩加速度下降 ,但心率及心输出量均无显著性变化 ;(2 )异氟醚降压组与非降压组间同一时间点血中S1 0 0B蛋白浓度无明显差异。降压组术后第 1天及第 2天血中S1 0 0B蛋白浓度均显著升高 (F =2 94 4 ,P =0 0 1 8)。结论 在颅内动脉瘤夹闭术中应用异氟醚控制性降压可能加重了术后脑损伤 ,不利于病人围麻醉期脑功能的保护 相似文献
96.
Dr. Yen-Chun Lin MD Jiahn-Shing Lee MD Shiu-Chen Wu MD Ling-Yuh Kao MD Chia-Yun Li MD Ken-Kuo Lin MD 《Annals of Ophthalmology》2003,35(1):19-24
This study analyzed the feasibility of fitting keratoconus-affected corneas with nonkeratoconus rigid gas-permeable (RGP)
contact lenses. We retrospectively studied patients with a diagnosis of keratoconus in the past 10 years who were fitted successfully
with nonkeratoconus RGP lenses by the same physician. Results confirmed nonkeratoconus RGP lenses as the first-line correction
tool. Additionally, we found a simple equation to speed the choice of the base curves of the lenses.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. 相似文献
97.
目的 探讨Y染色体无精症因子C区(azoospermia factor C,AZFe)无精症缺失基因(deleted-in-azoospermia,DAZ)家族基因拷贝缺失与中国男性原发不育之间的关系。方法 运用多重PCR与PCR-RFLP检测技术,对210例已生育男性、216例原发无精症与189例严重少精症患者Y染色体AzFc区域DAZ基因家族的基因拷贝数进行分析。结果 在所有已生育男性中未检出DAZ基因拷贝的完全或部分缺失,而在原发无精症与严重少精症患者中DAZ基因拷贝完全缺失率分别为8.8%和12.2%,DAZ1/DAZ2共缺失率分别为8.3%和5.3%。结论 在中国男性原发无精症与严重少精症患者中存在较高频率的DAZ基因拷贝缺失现象,提示Y染色体AZFc区域DAZ基因家族基因拷贝的完全与部分缺失是中国男性原发不育的遗传高风险因子。 相似文献
98.
99.
C Ambrose M James G Barnes C Lin G Bates M Altherr M Duyao N Groot D Church J J Wasmuth 《Human molecular genetics》1992,1(9):697-703
Within the Huntington's disease (HD) candidate region of 4p16.3, the D4S127 locus displays strong linkage disequilibrium with the defect and anchors a conserved haplotype found on many HD chromosomes. To isolate genes from this region we have applied the exon amplification technique to overlapping cosmids spanning D4S127. Here, we report the discovery of a new gene encoding a novel member of a family of protein kinases that specifically phosphorylate the activated forms of G protein-coupled receptors. Such kinases are thought to participate in desensitization of specific receptors, thereby blocking further signal transduction. This gene must now be carefully scrutinized to determine whether it might be involved in HD. 相似文献