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41.
To study the epidemiology of pediatric headache, we conducted a cross-sectional study of a randomized and proportional sample of 538 male and female students, 10 to 18 years old. They were in the 5th to 8th grade of the schools of Porto Alegre, RS Brazil. The headache disorders were classified on the basis of clinical interview as well as a physical and neurological examination using the operational diagnostic criteria of the International Headache Society (IHS The following headache prevalences were found: lifetime, 93.2%; last year, 82.9%; last week, 31.4%; last 24 h, 8.9%. Last week and last 24 h headache complaints were twice as prevalent in the female group. During the last year the prevalence of headache disorders was 72.8% for tension-type and 9.9% for migraine headache and was not associated with age distribution. Only the last year and last week prevalences of tension-type headache were significantly higher in the female group. The last year prevalence of headache disorder-proved to be positively associated with sex and age variables. The prevalence of headache disorders was found to be extremely high in this population group, requiring more attention on the part of investigators as a public health problem.  相似文献   
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This study was performed to experimentally evaluate the viability and coverage of diced cartilage grafts for cranial defects. Biparietal bone defects were prepared in each of 20 rabbits. Otogenous bone grafts were fixed to one side, whereas cartilage grafts taken from the right ear, diced, and wrapped with oxidized regenerated cellulose (Surgicel) were placed on other side. Parenchymal impression, contour, and ossification of all grafts in the 16 rabbits surviving after 8 weeks were evaluated with computed tomography and magnetic resonance imaging. The existence of ossification was examined pathologically. Parenchymal impression was significantly more frequent in bone grafts than in cartilage grafts (p < 0.05). This difference probably is attributable to the application technique. There was no significant radiographic difference in other parameters between the two groups. No significant difference in ossification was found. In conclusion, ossification was seen radiologically and pathologically in diced cartilage grafts. Because of autogenicity, ease of shaping, absence of postoperative warping, reduced resorption rates, and inherent viability and ossification properties, the authors suggest that diced cartilage grafts may be an alternative material for cranial defects, especially for frontal cranial reconstruction in which deformities may cause aesthetic and functional disabilities. The authors believe that further long-term studies also are needed.  相似文献   
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INTRODUCTION: We aimed to determine hemodynamic alterations in renal arteries that may have resulted from oral intake of sildenafil citrate in healthy volunteers. MATERIALS AND METHODS: Twelve healthy volunteers were included in our study. Renal Doppler ultrasonography (US) was performed before the drug intake to assess the basal values. Maximum peak systolic velocity, and resistivity and pulsatility indices were measured from the segmental branches of both renal arteries in all the examinations. After the basal measurements 50 mg of sildenafil or placebo were randomly given to the 12 subjects. Renal Doppler US examinations were carried out 1 h after sildenafil or placebo intake. On the following day sildenafil was administered to the subjects who had previously taken placebo or vice versa. Renal Doppler US was repeated after 1 h. The effect of sildenafil on renal vascular hemodynamics was evaluated by comparison of basal values with postplacebo and postsildenafil values. RESULTS: No statistically significant differences were found between the basal values of bilateral renal arteries and maximum peak systolic velocity, and resistivity and pulsatility index values measured after the placebo or sildenafil intake. CONCLUSION: We demonstrated that single-dose sildenafil did not cause any significant effect on renal artery hemodynamics in healthy individuals.  相似文献   
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泛昔洛韦等3种药物抗乙型肝炎病毒的体外实验研究   总被引:8,自引:1,他引:7  
 目的评价泛昔洛韦、膦甲酸钠及氧化苦参碱的体外抗HBV作用.方法采用MTT法检测3种药物对HepG2.2.15细胞的半数毒性浓度(TC5o),并在此基础上观察不同浓度药物作用于HepG2.2.15细胞后第3、5、7和9天培养上清中HBsAg、HBeAg及HBV DNA含量的变化,比较不同药物抗HBV的效果.结果泛昔洛韦和氧化苦参碱对HepG2.2.15细胞有明显的抗HBV活性,在实验浓度范围内,随着药物浓度增加和作用时间延长,其抗HBV活性增强;膦甲酸钠对HBV无明显抑制作用.结论泛昔洛韦和氧化苦参碱具有明显体外抗HBV活性,而膦甲酸钠体外对HBV无明显抑制作用.  相似文献   
47.

INTRODUCTION

Parastomal herniation occurs in 30–50% of colostomy formations. The aim of this study was to radiologically evaluate the mechanical defects at stoma sites in patients who had previously undergone a permanent colostomy with or without mesh at the index operation for colorectal cancer.

METHODS

A study was performed of all colorectal cancer patients (n=41) having an end colostomy between 2002 and 2010, with or without Prolene® mesh plication, with blinded evaluation of the annual follow-up staging computed tomography (CT) for stomal characteristics. The presence of parastomal hernias, volume, dimensions, grade of the parastomal hernia and abdominal wall defect size were measured by two independent radiologists, and compared with demographic and operative variables.

RESULTS

In those patients with radiological evidence of a parastomal hernia, Prolene® mesh plication significantly reduced the incidence of bowel containing parastomal hernias at one year following the procedure (p<0.05) and also reduced the diameter of the abdominal wall defect (p=0.006).

CONCLUSIONS

Prophylactic mesh placement at the time of the index procedure reduces the diameter of abdominal wall aperture and the incidence of parastomal hernias containing bowel. Future studies should use both objective radiological as well as clinical endpoints when assessing parastomal hernia development with and without prophylactic mesh.  相似文献   
48.
The purpose of this research was to determine if the accuracy of HIV saliva and serum test results were influenced by changes in collection sites. In order to do so, serum and saliva samples were collected from 615 subjects in eight different geographic settings. The oral fluid collection/testing systems utilized were the Orapette SalivaCard HIV-1/HIV-2 antibody test (Trinity Biotech, Ireland) and the Omni-SAI/Immuno Comb II HIV 1 & 2 Saliva Test (Orgenics Ltd, Israel). For comparison, serum samples were tested by ELISA (Ortho) with reactive results confirmed via HIV-1 and HIV-2 Western blots (Biotech/Dupont, Institute Pasteur). The HIV serum and oral fluid collections were conducted in numerous test sites, which provided a great diversity in temperature, lighting and physical layout. The tests proved to be 99.8% and 100% specific, and both were 100% sensitive, regardless of the physical setting of the collections. While these systems are not currently available in the US, this study clearly demonstrates they can accurately be utilized in a variety of clinical settings, providing great promise for future applications.  相似文献   
49.
OBJECTIVE: Onychomycosis is a common fungal infection of the toenails and can originate secondary to vascular abnormalities. The aim of this study was to evaluate the relationship between onychomycosis and venous insufficiency. METHODS: Forty-two patients with onychomycosis and 39 healthy control subjects who had normal toenails were enrolled in the study. Doppler examinations were performed with a commercially available scanner and a 7.5-MHz linear probe. Major superficial and deep veins of the lower limb, including long and short saphenous, femoral, and popliteal veins, were examined. Venous insufficiency was assessed with the Valsalva test. With the Doppler examination, retrograde flow of more than 1 second was accepted as venous insufficiency. RESULTS: Venous insufficiency was detected more frequently in patients with onychomycosis than in the control group (15 [35.7%] of 42 and 6 [15.4%] of 39, respectively; P = .037). Reflux was bilateral in 4 (26.7%) of 15 patients with onychomycosis, and in those 4 patients the onychomycosis was also bilateral. In 7 (46.7%) of 15 patients, onychomycosis and venous insufficiency were detected ipsilaterally, whereas there were no onychopathic features contralaterally. Although unilateral insufficiency was present in 4 (26.7%) of 15 patients, these patients had bilateral onychomycosis. CONCLUSIONS: We found a significant relationship between onychomycosis and venous insufficiency; therefore, we recommend a routine venous Doppler examination for patients with onychomycosis to diagnose or rule out venous insufficiency.  相似文献   
50.
The reality of health care is continuously changing. Therefore, nursing teachers have to encourage and promote a critical, inquiry-oriented approach to work. This demands self-reflection during the teacher education. Teaching training crystallizes the objectives of teacher education; the process of self-reflection should be seen especially there.  相似文献   
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