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131.
目的:探讨磁共振氢质子谱(1H-MRS)对原发性单侧起病帕金森病的诊断价值。方法:未经治疗的原发单侧症状PD患者50例为PD组,健康人42名为对照组。两组分别予以双侧壳核MRS检查,由仪器自带软件自动计算得双侧壳核代谢物比值:NAA/Cr,Cho/Cr,NAA/Cho。结果:PD组患者其症状对侧壳核NAA/cr比值分别较同侧及健康对照组双侧壳核相应比值均值明显下降(分别为1.23±0.22,1.38±0.33,1.33±0.16;t=2.616,P=0.01和t=2.324,P=0.02),而其NAA/Cho、Cho/Cr比值较同侧及对照组相应比值均值无显著差异。症状同侧壳核NAA/cr、NAA/Cho、Cho/Cr较对照组无明显差异。结论:原发性单侧症状PD其症状的对侧壳核早期就可能存在神经元的缺失或胶质增生,提示壳核磁共振波谱分析可为早期PD的临床诊断提供较为可靠的客观依据。  相似文献   
132.
Oral lichenoid drug eruptions   总被引:1,自引:0,他引:1  
OBJECTIVES: To identify, from amongst drugs reported as causing lichenoid drug eruptions, those affecting the oral mucous membranes and to review the clinical, histo-logical and immunological features of such oral lichenoid drug eruptions in comparison to oral lichen planus, amalgam contact lesions and lichen planus-like eruption in graft-versus-host disease (GVHD).
DATA SOURCES: Ovid® Medline data searches on CD-Rom were carried out for the years 1966–1996 to identify reports of oral lichenoid drug eruptions and their clinical, histological and immunological featureS. Articles retrieved were examined for further appropriate references in the period 1940–1996.
DATA EXTRACTION AND SYNTHESIS: Each paper was critically examined for evidence of a clinically verifiable lichenoid drug eruption affecting the oral mucous membranes and the effects of subsequent drug withdrawal. Available clinical, histological and immunological features were recorded. The papers examined were too diverse in nature to permit a structured criticism. The extracted data have been tabulated where appropriate.
CONCLUSIONS: The reports of oral lichenoid drug eruptions are considerably fewer than those of cutaneous eruptions and fewer drugs have been reported as causing oral rather than cutaneous lichenoid eruptionS. Histology and immunology cannot be used reliably to differentiate lichenoid drug eruptions from idiopathic lichen planus, amalgam contact lesions and lichen planus-like eruption in GVHD. Lichenoid drug eruptions may also show some histological characteristics of oral discoid lupus erythematosuS. An accepted protocol agreed by a number of international centres would permit the gathering of substantial information on LDE and could lead to a greater understanding of the mechanisms involved.  相似文献   
133.
Obstructive airways diseases (OAD) represent a huge burden of illness world‐wide, and in spite of the development of effective therapies, significant morbidity and mortality related to asthma and COPD still remains. Over the past decade, our understanding of OAD has improved vastly, and novel treatments have evolved. This evolution is the result of successful translational research, which has connected clinical presentations of OAD and underlying disease mechanisms, thereby enabling the development of targeted treatments. The next challenge of translational research will be to position these novel treatments for OAD for optimal clinical use. At the same time, there is great potential in these treatments providing even better insights into disease mechanisms in OAD by studying the effects of blocking individual immunological pathways. To optimize this potential, there is a need to ensure that translational aspects are added to randomized clinical trials, as well as real‐world studies, but also to use other trial designs such as platform studies, which allow for simultaneous assessment of different interventions. Furthermore, demonstrating clinical impact, that is research translation, is an increasingly important component of successful translational research. This review outlines concepts of translational research, exemplifying how translational research has moved management of obstructive airways diseases into the next century, with the introduction of targeted, individualized therapy. Furthermore, the review describes how these therapies may be used as research tools to further our understanding of disease mechanisms in OAD, through translational, mechanistic studies. We underline the current need for implementing basic immunological concepts into clinical care in order to optimize the use of novel targeted treatments and to further the clinical understanding of disease mechanisms. Finally, potential barriers to adoption of novel targeted therapies into routine practice and how these may be overcome are described.  相似文献   
134.
135.
MR fluoroscopy: initial clinical studies   总被引:2,自引:0,他引:2  
Magnetic resonance (MR) fluoroscopy is a method for high-speed MR image acquisition with the goals of short acquisition time per image (500 msec or less), high image rate (10 images or more per second), and high-speed image reconstruction (150 msec or less from data acquisition to image display). The authors present their results with the first two goals in volunteers. MR fluoroscopic image data were acquired with a limited flip angle pulse sequence with reduced repetition times (TRs) and fewer phase encodings used per image. The sequence was applied continuously, and images were formed by updating one set of data with data from the most recently taken measurements. Sample head images were generated with TR/echo times as small as 11/5.5 msec and 48 phase encodings for a total acquisition time of about 500 msec. Images were acquired while the volunteer flexed his head. Artifacts from the motion became less evident on images as progressively shorter acquisition times were used.  相似文献   
136.
Normal prostate gland: examination with color Doppler US   总被引:12,自引:0,他引:12  
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137.
Tetralogy of Fallot: MR findings   总被引:2,自引:0,他引:2  
Surgical treatment of patients with tetralogy of Fallot requires accurate definition of all anatomic structures, particularly the central pulmonary arteries. Magnetic resonance (MR) images of 22 patients with tetralogy of Fallot were studied to assess their usefulness in providing information regarding the spectrum of anatomic abnormalities in this condition. MR findings were compared with information obtained at catheterization (in 16 patients) and at surgery (in nine patients), both of which were performed within 3 months of MR imaging. Ventricular chamber enlargement and wall hypertrophy were clearly delineated in most of the 17 patients who were examined before definitive surgical repair, and ventricular septal defects were visualized in all 17. Palliative systemic-to-pulmonary shunts were visualized in 11 patients and could be evaluated for patency. Most important, the morphology and size of the right ventricular outflow tract and central pulmonary arteries could be accurately assessed. Pulmonary artery measurements obtained from MR images demonstrated excellent correlation with angiographic measurements. In six patients examined after complete surgical repair, MR images accurately reflected changes in pulmonary artery outflow tract morphology and complications, such as residual pulmonary artery stenosis and thrombosis. The findings suggest that MR imaging can complement or obviate catheterization in the evaluation of tetralogy of Fallot with regard to suitability for definitive surgical repair.  相似文献   
138.
139.
The conversion of hematopoietic to fatty marrow is known to correlate with physiologic decreases in intramedullary blood flow. To determine whether the chronology of conversion is altered in patients with hip ischemia, T1-weighted magnetic resonance (MR) images of the hips in 50 healthy people and 27 with documented avascular necrosis (AVN) were reviewed. The distribution of fatty (high-signal) versus hematopoietic (low-signal) marrow was noted with respect to age. All patients had fatty marrow in the femoral capital epiphysis and greater trochanter. Hematopoietic intertrochanteric marrow was seen in 95% (80 of 84) of femurs in control subjects less than 50 years old, but in only 12.5% (two of 16) of those in control subjects older than 50 years (P less than .005). Only 33% (19 of 57) of patients less than 50 years with AVN had predominantly hematopoietic intertrochanteric marrow (P less than .005). The early conversion to fatty marrow in most patients with AVN as depicted by MR imaging may be an effect of decreased vascularity of the proximal femur and may allow the identification of patients at increased risk for AVN.  相似文献   
140.
Fang  JL; Vaca  CE 《Carcinogenesis》1997,18(4):627-632
The effect of alcohol drinking on the formation of DNA adducts of acetaldehyde, the primary oxidative metabolite of ethanol, was investigated in humans. DNA was isolated from granulocytes and lymphocytes from 24 alcoholic patients and 12 control subjects. DNA adduct levels were measured by 32P-postlabelling using reversed-phase HPLC with on-line detection of radioactivity. A large interindividual variation in adduct levels was observed. The average adduct levels in granulocyte and lymphocyte DNA from alcoholic patients were 3.4 +/- 3.8 and 2.1 +/- 0.8 adducts/10(7) nucleotides (n = 24), respectively. These levels were 13- and 7-fold higher than the corresponding levels in control subjects (P<0.001). The average adduct level in granulocyte DNA from alcoholic patients was 60% higher than in lymphocyte DNA (P<0.01). Our results, in conjunction with the genotoxicity of acetaldehyde, thus suggest the formation of DNA adducts of acetaldehyde as a plausible mechanism explaining the involvement of alcohol drinking in carcinogenesis.   相似文献   
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