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101.
OBJECTIVE: To assess the relationship between energy intake from fat and anthropometric, biochemical, and dietary measures of nutritional adequacy and safety. DESIGN: Three-year longitudinal study of children participating in a randomized controlled trial; intervention and usual care group data pooled to assess effects of self-reported fat intake; longitudinal regression analyses of measurements at baseline, year 1, and year 3. PARTICIPANTS: Six hundred sixty-three children (362 boys and 301 girls), 8 to 10 years of age at baseline, with elevated low-density lipoprotein cholesterol, who are participants of the Dietary Intervention Study in Children. MEASURES: Energy intake from fat assessed from three 24-hour recalls at each time point was the independent variable. Outcomes were anthropometric measures (height, weight, body mass index, and sum of skinfolds), nutritional biochemical determinations (serum ferritin, zinc, retinol, albumin, beta-carotene, and vitamin E, red blood cell folate, and hemoglobin), and dietary micronutrients (vitamins A, C, E, thiamin, riboflavin, niacin, vitamins B-6, B-12, folate, calcium, iron, zinc, magnesium, and phosphorus). RESULTS: Lower fat intake was not related to anthropometric measures or serum zinc, retinol, albumin, beta-carotene, or vitamin E. Lower fat intake was related to: 1) higher levels of red blood cell folate and hemoglobin, with a trend toward higher serum ferritin; 2) higher intakes of folate, vitamin C, and vitamin A, with a trend toward higher iron intake; 3) lower intakes of calcium, zinc, magnesium, phosphorus, vitamin B-12, thiamin, niacin, and riboflavin; 4) increased risk of consuming less than two-thirds of the Recommended Dietary Allowances for calcium in girls at baseline, and zinc and vitamin E in boys and girls at all visits. CONCLUSIONS: Lower fat intakes during puberty are nutritionally adequate for growth and for maintenance of normal levels of nutritional biochemical measures, and are associated with beneficial effects on blood folate and hemoglobin. Although lower fat diets were related to lower self-reported intakes of several nutrients, no adverse effects were observed on blood biochemical measures of nutritional status. Current public health recommendations for moderately lower fat intakes in children during puberty may be followed safely.  相似文献   
102.
PURPOSE: The aim of the current study was to control the hypothetical effects of decreased laser energy delivered to the peripheral cornea during phototherapeutic keratectomy (PTK) and provide quantitative calculation of induced low and high order aberrations. METHODS: We employed a model eye to simulate the refractive effect of homogeneous laser corneal irradiation, as in PTK, for different laser fluences (range 125 to 225 mJ/cm2) and treatment depths up to 200 microm. RESULTS: The hyperopic shift induced by the relatively lower energy delivered at the peripheral ablation zone during PTK was proportional to the treatment depth and inversely proportional to the energy fluence. The hyperopic shift calculated using the above ablation parameters was lower compared to previously reported clinical results. Higher order wavefront aberration (total root mean square) changes were of minimal significance for treatment depths up to 200 microm. CONCLUSIONS: After PTK, a hyperopic shift cannot be attributed to the energy delivery method alone. Modification of laser energy delivery algorithms may only minimize PTK-induced hyperopia.  相似文献   
103.
Photorefractive keratectomy with a small spot laser and tracker   总被引:2,自引:0,他引:2  
BACKGROUND: The Autonomous Technologies LADARVision excimer laser system utilizes an eye tracking mechanism and a small spot for photorefractive keratectomy. METHODS: One hundred and two eyes of 102 patients were treated for -1.50 to -6.25 D of spherical myopia at the spectacle plane using a 6-mm diameter ablation zone. One year follow-up was available for 93 eyes (91%). RESULTS: Uncorrected visual acuity for eyes treated for distance vision was 20/40 or better in 99% (n = 90), and 20/20 or better in 70% (n = 64) of eyes at 12 months. Spectacle-corrected visual acuity was 20/25 or better in all 92 eyes reported; no eye lost more than 2 lines of spectacle-corrected visual acuity, and only 1 eye (1.0%) experienced a loss of 2 lines (20/12.5 to 20/20) at 1 year. The refractive result was within +/- 0.50 D of the desired correction in 75% (n = 70), and within +/- 1.00 D in 93% (n = 86) of eyes at 12 months. Refractive stability was achieved between 3 and 6 months. Corneal haze was graded as trace or less in 100% of the 93 eyes. No significant reductions were noted in contrast sensitivity or endothelial cell density. CONCLUSIONS: Patients treated with the Autonomous Technologies LADARVision excimer laser system for -1.50 to -6.25 D of spherical myopia with 1 year follow-up had uncorrected visual acuity of 20/20 or better in 70%, no significant loss of spectacle-corrected visual acuity, no reduction of endothelial cell density or contrast sensitivity, and low levels of corneal haze.  相似文献   
104.
目的探讨颅鼻沟通瘤的手术入路和术后颅底组织缺损的修复方法。方法对5例鼻腔鼻窦肿瘤累及前颅底的手术入路、手术方法、修复材料、并发症、手术效果及生存率进行回顾性分析。结果全部病人随访3~5年,无脑脊液鼻漏、颅内感染等明显并发症。3年生存率为100%,5年生存率为80%。结论扩大鼻侧切开联合房垛样额骨开窗切除颅鼻沟通瘤,修复颅底缺损、重建功能是一种简便、安全、有效的方法。  相似文献   
105.
目的探讨重症阻塞性睡眠呼吸暂停低通气综合征的治疗方法,提高临床疗效和减少并发症。方法对15例经多导睡眠监测仪监测确认为重症阻塞性睡眠呼吸暂停低通气综合征患者术前进行为期1W的持续正压通气,再进行改良腭咽成形和等离子软腭、悬雍垂、舌根及下鼻甲消融,扩大咽气道。结果术后随访3~6m,无明显并发症,所有患者均取得了满意效果。患者射频治疗前和治疗12W后多导睡眠参数比较显示治疗后Ⅰ+Ⅱ期睡眠时间明显缩短,Ⅲ+Ⅳ期睡眠时间明显延长,睡眠效率及最低脉氧饱和度(LspO2)均显著提高(P<0.01);呼吸暂停低通气指数减低及打鼾时间缩短均较治疗前相比差异非常显著(P<0.01)。患者射频治疗12W后软腭长主及悬雍垂度的缩短及鼾声评级的降低均较治疗前相差非常显著(P<0.01)。Epworth嗜睡程度评分亦较治疗前明显降低(P<0.01)。结论持续正压通气、腭咽成形术和等离子消融综合治疗阻塞性睡眠呼吸暂停低通气综合征具有较好的近期疗效,且方便、安全、微创、恢复快,无不良反应,有较好的发展前景,值得推广应用。  相似文献   
106.
目的探讨提高阻塞性睡眠呼吸暂停低通气综合征(obstructivesleepapneahypopneasyndrome,OSAHS)的有效治疗方法。方法采用等离子低温射频舌根部分切除术治疗72例OSAHS,术前及术后12周进行多导睡眠仪监测和Epworth嗜睡程度评分确定治疗效果。结果术后舌根体积明显缩小,自觉症状明显改善,Epworth嗜睡程度评分较治疗前明显降低和AHI明显降低。结论等离子低温射频舌根部分切除术在阻塞性睡眠呼吸暂停综合征的治疗中显示出一定的可行性、有效性和安全性。为临床医师提供了一种新的、理想的治疗手段。在上气道阻塞性疾病的治疗中将有更加广阔的应用前景。  相似文献   
107.
软腭等离子射频打孔消融治疗阻塞性睡眠呼吸暂停综合征   总被引:1,自引:0,他引:1  
目的探讨等离子低温射频软腭打孔消融对阻塞性睡眠呼吸暂停低通气综合征的临床疗效.方法对65例经多导睡眠图监测确诊为阻塞性睡眠呼吸暂停低通气综合征的患者行软腭等离子低温射频打孔消融术,缩短软腭及悬雍垂.结果术后随访3~6个月,患者均取得了满意效果.患者射频治疗前和治疗12周后多导睡眠参数比较显示治疗后Ⅰ+Ⅱ期睡眠时间明显缩短,Ⅲ+Ⅳ期睡眠时间明显延长,睡眠效率及最低脉氧饱和度(LSpO2)均显著提高(P<0.05);呼吸暂停低通气指数减低及打鼾时间缩短与治疗前相比差异非常显著(P<0.01).患者射频治疗12周后软腭长度及悬雍垂长度的缩短及鼾声评级的降低均较治疗前有显著差异(P<0.01).Epworth嗜睡程度评分亦较治疗前明显降低(P<0.01).结论等离子低温射频软腭打孔消融对于轻度OSAHS患者具有较好的近期疗效,且方便、安全、微创、康复快,无不良反应,有较好的发展前景,值得推广应用.  相似文献   
108.
BackgroundThere is currently a wide therapeutic arsenal for migraine patients, without a single first-line preventive drug and we choose the different available alternatives taking into account comorbidities, national guidelines, previous treatments and personal experiences.Our objective was to evaluate the differences in the use of migraine treatments between neurologists from different countries.MethodsThis is a multi-centre observational study carried out by neurologists from specialized headache units in seven countries, retrospective with consecutive inclusion of all patients presenting with a migraine diagnosis, over a period of three months.ResultsA total of 734 patients were recruited but only 600 were considered in the analysis in order to homogenize the patient cohorts from countries: 200 Spain (ES), 100 Italy (IT), 85 Russia (RUS), 80 Germany (DE), 60 Portugal (PT), 45 Poland (PL) and 30 Australia (AU). 85.4 % of patients were women with a mean age of 42.6 ± 11.8 years. Considering previous and current preventive treatment, the order of use was: antidepressants (69.3 %), antiepileptic drugs (54.7 %), beta-blockers and antihypertensive drugs (49.7 %), OnabotulinumtoxinA (44.0 %) and others (36.2 %).Statistically significant differences were found between all pharmacological classes: antidepressants were commonly used in all countries, with the exception of Poland (AU: 76.7 %, IT: 71.0 %, DE: 60.0 %, PL: 31.1 %, PT: 71.7 %, RUS: 70.6 %, ES: 78.5 %; p < 0.0001); antiepileptic drugs were more frequently prescribed in Portugal, Australia and Spain (AU: 73.3 %, IT: 40.0 %, DE: 37.5 %, PL: 48.9 %, PT: 85.0 %, RUS: 29.4 % and ES: 69.0 %; p < 0.0001); beta-blockers and antihypertensive drugs were frequently used in all countries except Italy (AU: 60.0 %, IT: 14.0 %, DE: 53.8 %, PL: 48.9 %, PT: 68.3 %, RUS: 49.4 % and ES: 59.0 %; p < 0.0001); BTX-A were predominately used in Spain, Italy and Australia (AU:56.7 %, IT:58.0 %, DE:20.0 %, PL: 42.2 %, PT: 26.7 %, RUS: 24.7 % and ES: 58.5 %; p < 0.0001) and others were most frequently used in Poland (AU: 0.0 %, IT: 19.0 %, DE: 42.5 %, PL: 95.6 %, PT: 31.7 %, RUS: 3.5 % and ES: 49.5 %; p < 0.0001). If only patients without comorbidities are considered (200/600), statistically differences between countries persist in all preventive treatments.ConclusionsThere is heterogeneity in the choice of preventive treatment between different countries. Prospective comparative studies of the different oral and subcutaneous alternatives would help to create a global therapeutic algorithm that would guarantee the best option for our patients.  相似文献   
109.
110.
Dyer  MJ; Heward  JM; Zani  VJ; Buccheri  V; Catovsky  D 《Blood》1993,82(3):865-871
We have investigated the structure of the Ig heavy (IGH) chain locus in 309 cases of acute leukemia. Seventy-one cases of B-cell precursor (BCP) acute lymphoblastic leukemia (ALL) were analyzed: in six cases deletion of joining (JH) segments in the presence of cytogenetically normal chromosome 14 was observed. Similar deletions were seen in 1 out of 8 cases of biphenotypic acute leukemia analyzed: this case exhibited t(9:22)(q34;q11) and coexpressed both myeloid and B cell differentiation antigens. Five of the 7 cases analyzed had deleted the JH segments from both chromosomes. Because these deletions may have contributed to the pathogenesis of the disease we have attempted to define their boundaries. Using probes that map both 5' and 3' of JH, the 3' (centromeric) boundary of the deletions was mapped to an approximately 30-kb central region of the 60 kb between C delta and C gamma 3 in 10 of the 12 deleted chromosomes. In the remaining two chromosomes, the 3' boundary mapped to S mu. The 5' (telomeric) boundary could not be defined. However, three cases with biallelic deletion of JH showed biallelic deletion of the most proximal variable (VH) (VH6 and VH5-B2) genes, indicating that the deletions spanned over 500 kb. VH5-B1 and VH5-B3 were retained in germline configuration and no gross deletions were observed using a VH3 subgroup-specific probe, indicating that the 5' boundary mapped within the VH locus. Unusual deletions of the portion of the IgH locus including JH segments and the C mu and C delta genes may occur in acute leukemias with immunophenotypic evidence of commitment to the B cell differentiation pathway. The possible consequences of the deletions remain to be determined. However, the clustering of the centromeric boundary of the deletions to S mu and to a region between the C delta-C gamma 3 genes, a known "hot spot" for recombination, may indicate the operation of a distinct pathogenic mechanism.  相似文献   
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