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91.
目的:研究胰腺内分泌肿瘤的胃肠多肽受体表达状况。方法:采用储磷放射自显影技术显示和定量分析胰泌素、蛙皮素、肠血管活性多肽、胆囊收缩素、生长抑素受体在胰腺内分泌肿瘤的表达特征。结果:胃泌素瘤表达蛙皮素、生长抑素受体,胰泌素和肠血管活性多肽受体,其中生长抑素受体亲和力及结合能力显高于其它受体。肠血管活性多肽瘤表达生长抑素,肠血管活性多肽和B型胆囊收缩素受体,以B型胆囊收缩素受体亲和力及结合能力最高。胃泌素瘤或VIP瘤所表达的胰泌素、蛙皮素、肠血管活性多肽、胆囊收缩素和生长抑素受体均呈高亲和力、单结合位点特征。生长抑素瘤和胰高糖素瘤未能测得上述5种胃肠多肽受体。结论:除生长抑素受体外,胃泌素瘤和肠血管活性多肽瘤还表达胰泌素、蛙皮素、肠血管活性多肽受体。  相似文献   
92.
Huntington’s disease is an autosomal dominant neurodegenerative disease caused by a CAG repeat expansion in the huntingtin gene. Heart disease is the second leading cause of death in patients with Huntington’s disease. This study was to evaluate whether cardiac Fas-dependent and mitochondria-dependent apoptotic pathways are activated in transgenic mice with Huntington’s disease. Sixteen Huntington’s disease transgenic mice (HD) and sixteen wild-type (WT) littermates were studied at 10.5 weeks of age. The cardiac characteristics, myocardial architecture, and two major apoptotic pathways in the excised left ventricle from mice were measured by histopathological analysis, Western blotting, and TUNEL assays. The whole heart weight and the left ventricular weight decreased significantly in the HD group, as compared to the WT group. Abnormal myocardial architecture, enlarged interstitial spaces, and more cardiac TUNEL-positive cells were observed in the HD group. The key components of Fas-dependent apoptosis (TNF-alpha, TNFR1, Fas ligand, Fas death receptors, FADD, activated caspase-8, and activated caspase-3) and the key components of mitochondria-dependent apoptosis (Bax, Bax-to-Bcl-2 ratio, cytosolic cytochrome c, activated caspase-9, and activated caspase-3) increased significantly in the hearts of the HD group. Cardiac Fas-dependent and mitochondria-dependent apoptotic pathways were activated in transgenic mice with Huntington’s disease, which might provide one of possible mechanisms to explain why patients with Huntington’s disease will develop heart failure.  相似文献   
93.
AIM:To investigate the 10-year results of treating low rectal cancer by a single surgeon in one institution.METHODS:From Oct 1998 to Feb 2009,we prospectively followed a total of 62 patients with cT2-4 low rectal cancer with lower tumor margins measuring at 3 to 6 cm above the anal verge.All patients received neoadjuvant chemoradiation(CRT) for 6 wk.Among them,85% of the patients received 225 mg/m2/d 5-fluorouracil using a portable infusion pump.The whole pelvis received a total dose of 45 Gy of irradiation in 25 fractions over 5 wk.The interval from CRT completion to surgical intervention was planned to be approximately 6-8 wk.Total mesorectal excision(TME) and routine defunctioning stoma construction were performed by one surgeon.The distal resection margin,circumferential resection margin,tumor regression grade(TRG) and other parameters were recorded.We used TRG to evaluate the tumor response after neoadjuvant CRT.We evaluated anal function outcomes using the Memorial Sloan-Kettering Cancer Center anal function scores after closure of the defunctioning stoma.RESULTS:The median distance from the lower margin of rectal cancer to the anal verge was 5 cm:6 cm in 9 patients,5 cm in 32 patients,4 cm in 10 patients,and 3 cm in 11 patients.Before receiving neoadjuvant CRT,45 patients(72.6%) had a cT3-4 tumor,and 21(33.9%) patients had a cN1-2 lymph node status.After CRT,30 patients(48.4%) had a greater than 50% clinical reduction in tumor size.The final pathology reports revealed that 33 patients(53.2%) had a ypT3-4 tumor and 12(19.4%) patients had ypN1-2 lymph node involvement.All patients completed the entire course of neoadjuvant CRT.Most patients developed only Grade 1-2 toxicities during CRT.Thirteen patients(21%) achieved a pathologic complete response.Few post-operative complications occurred.Nearly 90% of the defunctioning stomas were closed within 6 mo.The local recurrence rate was 3.2%.Pathologic lymph node involvement was the only prognostic factor predicting disease recurrence(36.5% vs 76.5%,P = 0.006).Ne  相似文献   
94.
Aims and objective. To investigate the relationship between family caregivers’ self‐efficacy for managing behavioural problems of older people with dementia and their behavioural problems in Taiwan. Background. Older people with dementia commonly have at least one behavioural problem, which caregivers complain is difficult to handle. To provide interventions that can help caregivers more effectively manage the behavioural problems of care receivers with dementia, caregivers’ self‐efficacy on managing behavioural problems must be assessed. However, it is not clear yet how these behavioural problems of older people with dementia may influence caregivers’ self‐efficacy for managing behavioural problems. Design. A prospective, correlational study. Method. Eighty dyads of older people with dementia and their family caregivers were recruited from neurological clinics of a medical centre in Taiwan. Care receivers were assessed for behavioural problems using the Chinese version of Cohen‐Mansfield Agitation Inventory, community form. Caregivers’ self‐efficacy for managing care receivers’ agitation was measured by the research team‐developed Agitation Management Self‐Efficacy Scale. Results. Caregiver self‐efficacy for managing behavioural problems was significantly and positively associated with more caregiver education, greater duration of caregiving and with care receivers’ less physically non‐aggressive behaviours. When caregiver characteristics were controlled for in hierarchical regression analysis, physically non‐aggressive behaviours explained 6% of the variance in caregiver self‐efficacy. Conclusions. Results of this study contradict the general belief that physically aggressive behaviours of elders with dementia are more difficult for family caregivers to handle than other behavioural problems. Clinicians need to address physically non‐aggressive problem behaviours. Relevance to clinical practice. Nurses could assess older patients with dementia for physically non‐aggressive behaviours and train less educated caregivers to improve their self‐efficacy for managing problem behaviours, thus enhancing the quality of life for both caregivers and care receivers.  相似文献   
95.
The effects of peer influence on adolescent cigarette smoking were investigated in longitudinal study of 309 white, middle-class subjects in the 8th and 11th grades. Subjects provided data on their smoking behavior, the proportion of their friends who smoked, and the identity of their best friend. Data from the person named as best friend was used to measure peer smoking, rather than the adolescent's perceptions of the friend's smoking. Peer influence was defined as the difference between the subject's smoking behavior and that of their best friend. This definition (PI1) minimized the confounding of peer influence with selective association. The effects of peer influence on change in smoking behavior were found to be stronger for 8th than 11th graders and for boys than girls. When the proportion of friends who smoke (PI2) was used as the measure of peer influence, the effects of peer influence were stronger for 11th than 8th graders. The relative merits of the two measures are discussed, and the argument is made that the difference between friend and adolescent smoking is a more appropriate measure of peer influence than the proportion of friends who smoke.  相似文献   
96.
A total of 368 blood specimens were resampled from a serum collection containing 2914 blood samples which were collected by a random sampling in Taiwan in 1991. The plaque reduction neutralization test was applied to evaluate the neutralizing ability to two strains of Japanese encephalitis viruses, i.e. Nakayama (the present vaccine strain) and JE5 (a Taiwan isolate). The result revealed that antibodies against JE virus were present in each stratified age group. Antibody positive rates were both highest in the group older than 70 years although the lowest rates were located in different groups. In addition, the result showed that the immunogenicity potency of the antibody induced by the vaccine strain did not have a good coverage against JE5. The rate of neutralizing antibodies above the level of protective efficacy of the present vaccine was limited as low as 37.93%. Efficacy of the vaccine used at present was apparently not efficient. Consideration of a more promising vaccine may be necessary.  相似文献   
97.
98.
A high-pressure liquid chromatographic assay was developed for the quantitative analysis of a new cephalosporin, BMY-28142, in plasma and urine. The plasma method involved protein precipitation with acetonitrile and trichloroacetic acid followed by extraction of the acetonitrile into dichloromethane. After centrifugation, the organic phase was discarded, the aqueous solution was injected into a reverse-phase column, and peaks were detected at 280 nm. The urine method involved dilution of a urine sample with sodium acetate buffer (pH 4.25) and direct injection into the high-pressure liquid chromatography system. The assay validation data indicate that the assays for BMY-28142 in plasma and urine were specific, accurate, and reproducible. The analytical methods were applied to the determination of protein binding in human serum and to a pharmacokinetic study in rats. The results of the protein-binding study indicated that BMY-28142 was 16.3% bound to human serum proteins. In the pharmacokinetic study in rats, the maximum level in plasma of 38.7 micrograms/ml was achieved at 2.33 h after administration of a subcutaneous dose of 100 mg/kg. The levels in the plasma then declined with an elimination half-life of about 0.56 h. The mean values for the steady-state volume of distribution and total body clearance were 0.46 liters/kg and 11.9 ml/min per kg, respectively. The 0- to 24-h excretion of intact BMY-28142 in urine accounted for 88.6% of the dose.  相似文献   
99.
骨骼肌缺血再灌注损伤的机制   总被引:1,自引:0,他引:1  
目的:对近年来骨骼肌缺血再灌注损伤的发病机制进行综述。资料来源:应用计算机检索MEDLINE、CBM、CNKI数据库及手工检索1998-01/2006-11期间的相关文献。中文检索词包括"骨骼肌,缺血再灌注损伤,发病机制";英文检索词有"Skeletal muscle","ischemia and reperfusion injury","oxygen freeradical","calcium overload"和"neutrophil"。资料选择:共收集到相关文献300篇,阅读全部文章的文题和大部分文章的摘要。选择文献所述内容与骨骼肌缺血再灌注损伤机制相关的文献。排除重复性研究。资料提炼:共得到符合纳入条件的文献55篇,排除145篇。选择其中30篇进行分析,英文24篇,中文6篇。资料综合:骨骼肌缺血再灌注损伤的机制由于有许多因素的介入而变的十分复杂,目前主要以氧自由基学说,钙超载学说和中性粒细胞学说为主,同时也注意到了一氧化氮和细胞凋亡以及微循环的无复流现象在其中的作用。结论:氧自由基学说,钙超载学说,中性粒细胞学说,一氧化氮,细胞凋亡以及微循环的无复流现象在骨骼肌缺血再灌注损伤中起着重要作用。  相似文献   
100.
AIM: To study Helicobacterpylori (H pylori) infection in relation to E-cadherin (E-cad) promoter polymorphism and hypermethylation in GCs. METHODS: Specimens were taken from representative cancerous lesions and adjacent non-cancerous epithelia of 67 resected GCs. H pylori was detected by real-time PCR of the cagA gene from non-neoplastic epithelium. E-cad promoter polymorphism and hypermethylation were determined by restriction fragment length polymorphism analysis and methylation-specific PCR, respectively. Expression of E-cad protein was determined by immunohistochemistry. RESULTS: H pylori was found in 57% of patients with GC. H pylori infection was more frequently found in tumors with the -160C/C genotype than those with the -160C/A and -160A/A genotypes (74% vs 47%, P= 0.02). H pylori infection was associated with E-cad methylation in non neoplastic epithelium; however, no significant difference in H pylori was observed between methylated and unmethylated cancerous lesions. CONCLUSION: Patients with the -160C/C genotype might require H pylori infection to promote the inactivation of CDH1, suggesting that H pylori infection might affect GC in an initial stage because polymorphism is germ line. Mechanism of hypermethylation of CDH1 promoter in GC is complex, and H pylori infection might affect it in an initial stage.  相似文献   
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