全文获取类型
收费全文 | 104818篇 |
免费 | 8737篇 |
国内免费 | 6124篇 |
专业分类
耳鼻咽喉 | 1115篇 |
儿科学 | 1544篇 |
妇产科学 | 2304篇 |
基础医学 | 12414篇 |
口腔科学 | 2006篇 |
临床医学 | 14030篇 |
内科学 | 16588篇 |
皮肤病学 | 895篇 |
神经病学 | 5671篇 |
特种医学 | 3537篇 |
外国民族医学 | 42篇 |
外科学 | 11255篇 |
综合类 | 14821篇 |
现状与发展 | 23篇 |
一般理论 | 20篇 |
预防医学 | 6124篇 |
眼科学 | 2865篇 |
药学 | 10716篇 |
57篇 | |
中国医学 | 4835篇 |
肿瘤学 | 8817篇 |
出版年
2024年 | 281篇 |
2023年 | 1505篇 |
2022年 | 3814篇 |
2021年 | 4984篇 |
2020年 | 3531篇 |
2019年 | 3251篇 |
2018年 | 3548篇 |
2017年 | 2930篇 |
2016年 | 2846篇 |
2015年 | 4414篇 |
2014年 | 5622篇 |
2013年 | 5016篇 |
2012年 | 7537篇 |
2011年 | 8276篇 |
2010年 | 4980篇 |
2009年 | 3820篇 |
2008年 | 5276篇 |
2007年 | 5530篇 |
2006年 | 5412篇 |
2005年 | 5701篇 |
2004年 | 3834篇 |
2003年 | 3399篇 |
2002年 | 3017篇 |
2001年 | 2442篇 |
2000年 | 2654篇 |
1999年 | 2707篇 |
1998年 | 1582篇 |
1997年 | 1485篇 |
1996年 | 1308篇 |
1995年 | 1161篇 |
1994年 | 983篇 |
1993年 | 638篇 |
1992年 | 998篇 |
1991年 | 807篇 |
1990年 | 684篇 |
1989年 | 601篇 |
1988年 | 593篇 |
1987年 | 529篇 |
1986年 | 420篇 |
1985年 | 331篇 |
1984年 | 208篇 |
1983年 | 159篇 |
1982年 | 85篇 |
1981年 | 98篇 |
1980年 | 83篇 |
1979年 | 115篇 |
1978年 | 54篇 |
1977年 | 56篇 |
1975年 | 44篇 |
1974年 | 45篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
R L Chen I J Su K H Lin S H Lee D T Lin W M Chuu K S Lin L M Huang C Y Lee 《American journal of clinical pathology》1991,96(2):171-176
Ten cases of pediatric fulminant hemophagocytic syndrome, encountered between 1986 and 1989, are described. They occurred in the summer, and the patients presented with fever, jaundice, hepatosplenomegaly, pancytopenia, coagulopathy, and abnormal liver function. Bone marrow studies revealed infiltration by atypical T-lymphoid cells, rare B immunoblasts, and mature histiocytes with hemophagocytosis. Initially, histiocytic medullary reticulosis was suspected in six cases. The clinical course was characterized by rapid deterioration, with a mean period of 16 days from onset of fever to death. The main causes of death were coagulopathy with multiple organ failure and opportunistic infection. In seven of eight cases studied by serologic assay and Southern blot hybridization, acute or active Epstein-Barr virus (EBV) infection was documented. It is suggested that an atypical or fulminant form of primary EBV infection distinct from classic infectious mononucleosis was prevalent in previously healthy children in Taiwan. Younger age involvement and seasonal clustering were characteristic of the disorder described. 相似文献
82.
Hsin-Yi Chen Mei-Ling Huang Yi-Yu Tsai Por-Tying Hung 《Optometry and vision science》2007,84(7):640-646
PURPOSE: To study the diagnostic ability of scanning laser polarimetry with variable corneal compensation (GDx VCC) for early glaucomatous (EG) eyes and glaucoma-suspect (GS) eyes in a Taiwan Chinese population. METHODS: This prospective cross-sectional study included 82 EG eyes (mean deviation, MD: -3.32 +/- 2.20 dB), 45 GS eyes (MD: -2.43 +/- 2.16 dB), and 62 normal eyes. Retinal nerve fiber layer thickness of each subject was measured using GDx VCC and Humphrey Field Analyzer visual field testing. Measured GDx VCC parameters were compared among groups. The area under the receiver operating characteristic (AROC) curve of each parameter was used to differentiate normal from EG eyes or GS eyes. The correlation between MD and each parameter was also evaluated. RESULTS: For both normal versus EG and normal versus GS, the largest AROC values were for nerve fiber indicator, superior average thickness, and inferior average thickness. There was no significant correlation between MD and GDx-VCC-measured parameters either in EG or GS eyes. CONCLUSIONS: GDx VCC shows only moderate ability to distinguish normal eyes from eyes with early glaucoma. However, its diagnostic role in eyes with suspicious discs and normal visual fields is uncertain at this moment in the Taiwan Chinese population. Further studies are needed to address this issue. 相似文献
83.
Single- and multiple-dose pharmacokinetics of ceftazidime in infected patients with varying degrees of renal function 总被引:2,自引:0,他引:2
To determine the single- and multiple-dose ceftazidime kinetics, we administered ceftazidime, 2 gm intravenous bolus every 12 hours, to 14 infected Chinese patients with various degrees of renal function. Blood samples were drawn in serial after the first and 7th dose and serum ceftazidime concentrations were measured by high pressure liquid chromatography. Ceftazidime concentration-time data were fitted to a two-compartment model with a nonlinear regression program. Ceftazidime kinetics was unaltered by repeated dosing. Both total body clearance and elimination rate constant of ceftazidime decrease significantly in proportion to the creatinine clearance estimated by Bjornsson's method. Renal insufficiency did not modify the steady-state volume of distribution (Vdss) of ceftazidime which, however, appeared to be larger than those reported previously. This larger Vdss may be explained by acute infection process, confinement to bed, and increased extracellular fluid volume as a result of hypoalbuminemia. Our study indicates the estimated creatinine clearance as a useful guide to ceftazidime dosage adjustment and also emphasizes the clinical relevance of conducting kinetic studies of antibiotics in infected patients. 相似文献
84.
K Yamada Y Ushio T Hayakawa N Arita T Y Huang M Nagatani N Yamada H Mogami 《Cancer research》1987,47(8):2123-2128
To assess the rationale of intraarterial (i.a.) 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea chemotherapy, distribution of 14C-labeled 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)- 3-nitrosourea in rat glioma was studied after i.a. or i.v. infusion. Immediately after infusion, the tumor located in the hemisphere of intracarotid infusion received 4.6-fold higher radioactivity than the tumor located contralaterally to intracarotid infusion and 2.8-fold higher radioactivity than i.v. infusion. The difference was kept up to 30 min after i.a. infusion. Autoradiographic observation indicated rather uniform distribution of the tracer in the central portion of i.a. infusion. However, in the periphery of i.a. infusion, distribution of the tracer was nonhomogenous. The results indicate that i.a. 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea chemotherapy is useful when the tumor has high blood flow and is located in the center of an infused area. 相似文献
85.
Forty patients with symptoms of internal derangement of the knee were examined arthroscopically under local anesthesia using a continuous irrigation solution of 0.2% lidocaine. Serum levels were measured during and following the procedure to determine peak levels obtained and to assure that toxic levels were not exceeded. The procedure was well tolerated by all patients and found to be adequate by the surgeon. No procedure was terminated because of discomfort. Lidocaine levels ranged from undetectable to 2.5 micrograms/ml with an average of 0.6 microgram/ml. No complications of lidocaine toxicity were noted by the anesthesiologist or the operating surgeon. This technique provides a safe and efficient method of meeting the demands for diagnostic and therapeutic arthroscopy in ambulatory patients. 相似文献
86.
Cortical spreading depression in the feline brain following sustained and transient stimuli studied using diffusion-weighted imaging 总被引:1,自引:0,他引:1
87.
Stenotrophomonas maltophilia bacteremia in adults: four years' experience in a medical center in northern Taiwan. 总被引:1,自引:0,他引:1
Wei-Sheng Wang Chang-Pan Liu Chun-Ming Lee Fu-Yuan Huang 《Journal of microbiology, immunology, and infection》2004,37(6):359-365
Stenotrophomonas maltophilia has become an important nosocomial pathogen in immunocompromised patients in Taiwan. Patients with underlying diseases such as diabetes, uremia, and solid malignancy are extremely vulnerable to this organism. S. maltophilia bacteremia has a mortality rate of up to 62% if appropriate antibiotics are not instituted early. Knowledge of the risk factors for infection as well as local susceptibility patterns is helpful in determining which patients should receive empirical antibiotics active against S. maltophilia. This study assessed the characteristics of 50 episodes of S. maltophilia bacteremia in 48 patients admitted between March 3, 1999 and May 21, 2003. The new fluoroquinolone levofloxacin showed promising in vitro activity against S. maltophilia in view of the increasing resistance of isolates to trimethoprim-sulfamethoxazole. For patients at risk for S. maltophilia infection, such as those receiving mechanical ventilation in the ICU or those with multiple vascular access devices, the need for antimicrobial agents to which S. maltophilia is normally sensitive should be considered in selecting empiric therapy. 相似文献
88.
皮肤交界性平滑肌瘤的复发与恶性转化 总被引:3,自引:0,他引:3
目的探讨皮肤交界性平滑肌瘤的复发与恶性转化。方法复习2例皮肤交界性平滑肌瘤及其复发恶性转化的临床病理特征、免疫组化表型及相关文献。结果2例病变位于下肢和额部,肉瘤组织平滑肌标记阳性。结论少数病理诊断为皮肤平滑肌瘤的病例,虽然浅表且组织形态良性,但其生物学恶性潜能尚不能确定,部分病例复发后可转变为典型的平滑肌肉瘤。 相似文献
89.
90.
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