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31.
Retrospective evaluation of carcinoid tumors of the appendix in children   总被引:2,自引:0,他引:2  
Carcinoids of the appendix are rare in children and are usually diagnosed incidentally on histologic investigation following appendectomy for appendicitis. To investigate the significance of the diagnosis of appendiceal carcinoid in children, we conducted a retrospective study of the treatment and follow-up of 36 children with histologically confirmed carcinoid tumors of the appendix. Between 1970 and 2000 a total of 36 patients (25 girls, 11 boys) were diagnosed with appendiceal carcinoid. The median age of the patients at diagnosis was 12.3 years (range 6-16 years). The indication for appendectomy was acute lower right quadrant pain in 27 cases and chronic right lower quadrant pain in 9 patients. In 27 specimens the tumor was localized at the apex, in 7 at the midportion, and in 2 at the base of the appendix. The median tumor diameter was 6 mm (range 3-17 mm). Concomitant severe appendicitis was diagnosed in 14 patients 2 with a perforated appendicitis. In only one tumor were mucin-producing cells detectable. After a median follow-up of 10 years (range 2 months to 30 years) all patients were tumor-free. None of the patients had a synchronous or metachronous noncarcinoid malignant tumor. Appendiceal carcinoids are usually asymptomatic, and the indication for surgical intervention is acute or chronic abdominal pains in the right lower quadrant. For most patients the prognosis is excellent after appendectomy. As in adults, appendectomy is the appropriate treatment.  相似文献   
32.
The aim of this study was to evaluate the association between bone mineral density (BMD) and objective maximal exercise measurements in adults with cystic fibrosis (CF). Twenty-five CF patients (19 males, 6 females, mean age 25.5 yr, range: 17–52) underwent BMD assessment and maximal-cycle ergometer exercise testing. We examined the relationship between gas exchange (% peak-predicted O2 uptake, CO2 output, O2 saturation), exercise performance (maximum power, exercise duration), and respiratory mechanics (tidal volume, rate) with lumbar spine and total proximal femur BMD. The strongest clinical correlate with BMD was forced expiratory volume at 1 s (lumbar spine Z-score, r = 0.36; total proximal femur Z-score, r = 0.68, p < 0.01). The strongest exercise correlate was % peak-predicted O2 uptake (lumbar spine Z-score, r = 0.44, p < 0.01; total proximal femur Z-score, r = 0.59, p < 0.01). There was a closer association between exercise parameters and total proximal femur BMD (r = 0.43–0.60) than with lumbar spine BMD (r = 0.04–0.45). Multiple regression analysis revealed VO2 to be the strongest independent predictor of BMD (R2 = 0.86, p < 0.001) followed by petCO2 and body mass index (R2 = 0.7 and 0.5, respectively, p < 0.01). Exercise appears to influence total proximal femur BMD more than lumbar spine BMD in CF. Exercise rehabilitation programs focusing on peripheral strength training may benefit those CF patients with low total proximal femur BMD.  相似文献   
33.
34.

Background

Various megaprostheses are currently available for reconstruction of the proximal femur after tumor resection. This study evaluates the survival and complications of a modular megaprosthesis for reconstruction of the proximal femur.

Materials and methods

We studied the medical files of 109 tumor patients (age range 16–86 years) who underwent proximal femoral reconstruction with the MRP® megaprosthesis from 2002 to 2011. There were 70 patients with metastases, 34 patients with bone sarcomas, and five patients with hematological malignancies; 82 were primary and 27 were revision reconstructions. Mean follow-up was 2.5 years; 31 patients had a minimum five-year follow-up. We evaluated the survival and function of the patients, and the survival and complications of the megaprostheses.

Results

Survival was significantly higher for the patients with bone sarcomas compared to those with metastases and hematological malignancies. Mean MSTS functional score was similar between patients with bone sarcomas and those with hematological malignancies and metastases, and between patients with primary and those with revision reconstructions. Overall survival of the MRP® megaprostheses was 74 % at 5 and 9 years. Fourteen (13.6 %) major complications occurred at a mean period of 1.4 years (range 3 months to 4.5 years); these included infection (5.8 %), dislocation (3.9 %), local recurrence (2.9 %), and acetabular fracture (1 %).

Conclusion

MRP® megaprostheses are a valuable reconstruction option after tumor resection of the proximal femur.
  相似文献   
35.
Human interleukin-4 (huIL-4) has been shown to inhibit the growth in vitro of cells from patients with acute lymphoblastic leukemia (ALL). With the aim of determining whether this cytokine might be useful in the treatment of patients with ALL, the effects of huIL-4 on human B- cell precursor ALL engrafted in severe combined immunodeficient (SCID) mice were examined. The inhibition of [3H] thymidine uptake of primary ALL cells by huIL-4 was maintained following engraftment and passage of leukemia in SCID mice. Five of seven xenograft leukemias showed significant inhibition in vitro by huIL-4 at concentrations as low as 0.5 ng/mL; furthermore, huIL-4 counteracted the proliferative effects of IL-7. When used to treat two human leukemias engrafted in SCID mice, huIL-4 200 microgram/kg/d, as a continuous 14-day subcutaneous infusion, suppressed the appearance of circulating lymphoblasts and extended survival of mice by 39% and 108%, respectively, the first demonstration of IL-4 activity against human leukemia in vivo. The mean steady-state huIL-4 level in mouse plasma during the infusion was 1.46 ng/mL (SEM +/- 0.14 ng/mL), which was similar to concentrations found to be effective in vitro. ALL cells obtained from mice relapsing after huIL-4 treatment continued to show inhibition by the cytokine in vitro. These data suggest that IL-4 may be useful in the treatment of patients with ALL.  相似文献   
36.
AIM: To determine the prevalence and severity of diabetic retinopathy in patients with type 2 diabetes in Luganville, the second largest town in Vanuatu. Additionally, to investigate risk factors for retinopathy and the effect of retinopathy on visual acuity (VA) within this group. METHOD: All 83 registered patients with type 2 diabetes in Luganville, a town of 13 121 people, were invited for an interview and anthropometric measurements. A questionnaire including assessment of hypertension and glycaemic control, which are known risk factors for diabetic retinopathy, was administered. This sample accounted for approximately 1.07% of Luganville's adult population. Presenting VA was measured. The retina was photographed with a non-mydriatic fundus camera and images later independently graded for the extent of retinopathy. RESULTS: 68 (82%) of the 83 patients attended. The mean (SD) age was 54 (11) years and 31 (46%) were male. Diabetic retinopathy was present in 36 (52.9%) of the sample. Sight-threatening retinopathy requiring urgent referral was present in 15 (22.1%) patients. Presenting VA was worse than 6/12 in the better eye in n = 32 (47%) and in up to half of these cases the principal cause was retinopathy. In addition, four people had uniocular blindness resulting from diabetes. The mean body mass index was lower in those patients with diabetes with retinopathy than in those without (p = 0.010), but there were no other significant differences between the two groups and, specifically, no difference in the frequency of retinopathy risk factors. 42 (61.8%) patients had hypertension (>or=135/85 mm Hg) or were taking antihypertensive therapy. CONCLUSIONS: The prevalence of registered patients with diabetes in Luganville's adult population was 1.07%. Diabetic retinopathy was highly prevalent in the sample (in 36, 52.9%), and in 15 (22.1%) there was a significant threat to sight, with up to 25% of the sample possibly already affected by decreased VA or blindness resulting from diabetes-related eye disease. Retinopathy risk factors were also prevalent. A diabetes screening programme with baseline ophthalmic assessment and follow-up are urgently needed to enable timely intervention and treatment.  相似文献   
37.
PURPOSE: To evaluate the effect of intravitreal bevacizumab (Avastin; Genentech, Inc., South San Francisco, CA) injections on visual acuity and foveal retinal thickness in patients with central retinal vein occlusion (CRVO). METHODS: In this prospective, noncomparative, consecutive, interventional case series, 46 patients received repeated intravitreal injections (1.25 mg) of bevacizumab. Main outcome measures were visual acuity (Snellen and ETDRS charts) and optical coherence tomography measurements in a 6-month follow-up period. RESULTS: Mean visual acuity improved from 20/250 at baseline to 20/80 at the 6-month follow-up (P < 0.001). ETDRS chart findings revealed a mean letter gain +/-SD from baseline to 6 months of 13.9 +/- 14.4 letters. Mean central retinal thickness +/-SD decreased from 535 +/- 148 microm at baseline to 323 +/- 116 microm at the 6-month follow-up. Ischemic CRVO was associated with significantly lower visual acuity than nonischemic CRVO (P < 0.001). However, visual acuity gain was similar in both groups. Independent of duration of symptoms, CRVO was associated with a similar gain in visual acuity. CONCLUSION: Intravitreal injection of bevacizumab appears to be a new treatment option for patients with macular edema secondary to CRVO.  相似文献   
38.
Lens opacities in adults in Pakistan: prevalence and risk factors   总被引:1,自引:0,他引:1  
PURPOSE: To investigate the prevalence and risk factors for lens opacity (LO) amongst a nationally representative sample of the adult population of Pakistan. METHODS: This national study of blindness and visual impairment (adults > or =30 years) used multistage, stratified, cluster random sampling. Grading of LO was conducted using the Mehra/Minassian classification system. LO, partly or wholly obscuring the red reflex, or previous cataract surgery were indicators of opacity. RESULTS: 16,402 (94.7%) adults were included in this analysis (study conducted 2002-2003). A total of 4,096 (standardized prevalence 20.9%, 95%CI: 20.3, 21.5%) adults were found to have LO. The highest prevalence of LO was found in Punjab province (22.2%), the lowest in Balochistan Province (18.0%). Significant positive associations were increasing age (multivariable odds ratio (OR) 3.2: 95%CI: 3.1, 3.4), hypertension (OR 1.2, 95%CI: 1.1, 1.3), history of diabetes (OR 2.6: 95%CI 2.0, 3.2) and smoking (OR 1.3: 95%CI: 1.1, 1.5). Higher body mass index (BMI) (OR 0.8: 95%CI 0.7, 0.9, heavy vs. normal BMI) and attendance to school (OR 0.6: 95%CI: 0.5, 0.8) were associated with lower risk of LO. Individuals in districts classified as hot were at significantly increased risk (OR 1.3: 95%CI: 1.1, 1.5), and those in wet districts (> 600 mm annual rainfall) had lower odds than individuals living in dry districts (OR 0.7: 95%CI: 0.6, 0.8). CONCLUSIONS: Almost a fifth of the adult population had LO. Significant positive associations were age, smoking status, hypertension, diabetes, and increased deprivation level. Protective factors included high BMI and educational achievement. The climatic associations offer novel hypothesis for further research into cataractogenesis.  相似文献   
39.
PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of the round anterior and sharp posterior optic edge profile of the Clariflex silicone intraocular lens (IOL) [AMO Inc, Santa Ana, California, USA] with that of the double-round edge profile of the SI40 (Phacoflex; AMO Inc, Santa Ana, California, USA) silicone IOL over a period of three years. DESIGN: Prospective, randomized, double-masked, bilateral clinical trial. METHODS: The study took place at the Department of Ophthalmology, Medical University of Vienna, Austria. Fifty-two patients with age-related cataracts (104 eyes) were included in the study. Each patient received an SI40 IOL (round edges) in one eye and a Clariflex IOL with OptiEdge (sharp posterior optic edge) in the other eye. Follow-up examinations were at one week, one month, six months, and one, two, and three years. Digital retroillumination images were taken of each eye. The amount of PCO was subjectively assessed with the slit-lamp and objectively assessed by automated image analysis software (the computer program Automated Quantification of After-Cataract [AQUA]; Vienna, Austria) one, two, and three years after surgery. RESULTS: The Clariflex lens showed markedly less PCO at one, two, and three years after surgery. The mean AQUA PCO score was 1.39 for the SI40 and 0.56 for the Clariflex lens after one year, estimated at 1.64 and 0.57 after two years, and at 2.04 and 0.64, respectively, after three years (scale zero to 10; P < .001). The Nd:YAG laser capsulotomy rate was far higher in the SI40 group (Five cases vs one case at three years). CONCLUSIONS: The sharp posterior optic edge profile of the Clariflex silicone IOL led to marked and consistently less PCO than the round-edged SI40 IOL one, two, and three years after surgery.  相似文献   
40.
Summary Fibroblasts derived from a skin biopsy of a patient with the Ehlers-Danlos syndrome (EDS) type IV were cultured in monolayer. The amount of collagen synthesized during a 24-h pulse was not different from that found with normal fibroblasts. Chromatographic procedures and immunofluorescence staining showed a normal synthesis of type I procollagen and collagen but a deficiency in synthesis of type III procollagen and collagen. This could be corroborated by radioimmuno assays showing a reduction in type III procollagen by about 90%. The secretion and degradation of collagens was not altered. The results demonstrate that the molecular defect in this particular patient is due to an impairment of the mechanism controlling the gene expression for type III procollagen.
Abbreviations BAPN -aminopropionitrile - CM carboxy-methyl - DEAE diethylaminoethyl - EDS Ehlers-Danlos syndrome - EDTA ethylendiaminetetracetate - S.C. subcutaneous  相似文献   
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