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Mathieson  JR; Mayo  JR; Staples  CA; Muller  NL 《Radiology》1989,171(1):111-116
The accuracies of chest radiography and computed tomography (CT) in the prediction of specific diagnoses in 118 consecutive patients with chronic diffuse infiltrative lung disease (DILD) were compared. The radiographs and CT scans were independently assessed by three observers without knowledge of clinical or pathologic data. The observers listed the three most likely diagnoses in order of probability and recorded the degree of confidence they felt in their first-choice diagnosis on a three-point scale. Confidence level 1 (definite) was reached with 23% of radiographic and 49% of CT scan readings, and the correct diagnosis was made with 77% and 93% of those readings, respectively (P less than .001). The correct first-choice diagnosis regardless of the level of confidence was made with 57% of radiographic and 76% of CT scan readings (P less than .001). The CT scan interpretations were most accurate in silicosis (93%), usual interstitial pneumonia (89%), lymphangitic carcinomatosis (85%), and sarcoidosis (77%). Observers correctly predicted whether a transbronchial or open lung biopsy was indicated with 65% of radiographs and 87% of CT scans (P less than .001). It is recommended that CT be performed before lung biopsy in all patients with chronic DILD.  相似文献   
153.
Staples  CA; Muller  NL; Miller  RR; Evans  KG; Nelems  B 《Radiology》1988,167(2):367-372
Computed tomography (CT) and mediastinoscopy were compared in 151 patients with bronchogenic carcinoma. In all patients in whom findings at mediastinoscopy were negative, all accessible nodes were either removed or sampled at thoracotomy. Several size criteria for identifying nodes as enlarged on CT scans were compared. The long axis greater than or equal to 15 mm and short axis greater than 10 mm had very low sensitivity (61%), and the long axis greater than 5 mm had a low specificity (23%). CT (long axis greater than 10 mm) allowed sensitivity equal to that of mediastinoscopy (79%) in the detection of mediastinal metastases, but the specificity with CT was lower (65% vs. 100%). In seven of 44 patients with nodes greater than 10 mm on CT scans and with positive findings at mediastinoscopy, tumor was present not in the enlarged nodes but rather in normal-sized nodes in a different nodal station. The sensitivity of CT for actual nodal stations involved with tumor was only 66%. Eighty-three percent of patients with false-negative findings at mediastinoscopy but only 33% of patients with false-negative findings at CT had surgically resectable stage IIIa disease.  相似文献   
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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   
157.
Two frequent missense mutations in Pendred syndrome   总被引:8,自引:3,他引:8  
Pendred syndrome is an autosomal recessive disorder characterized by early childhood deafness and goiter. A century after its recognition as a syndrome by Vaughan Pendred, the disease gene ( PDS ) was mapped to chromosome 7q22-q31.1 and, recently, found to encode a putative sulfate transporter. We performed mutation analysis of the PDS gene in patients from 14 Pendred families originating from seven countries and identified all mutations. The mutations include three single base deletions, one splice site mutation and 10 missense mutations. One missense mutation (L236P) was found in a homozygous state in two consanguineous families and in a heterozygous state in five additional non-consanguineous families. Another missense mutation (T416P) was found in a homozygous state in one family and in a heterozygous state in four families. Pendred patients in three non-consanguineous families were shown to be compound heterozygotes for L236P and T416P. In total, one or both of these mutations were found in nine of the 14 families analyzed. The identification of two frequent PDS mutations will facilitate the molecular diagnosis of Pendred syndrome.   相似文献   
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张美丽  胡宁丽 《医学争鸣》2005,26(19):1767-1767
1 临床资料 2004-03/2004-08将外周插管的中心静脉导管(peripherally inserted central catheter, PICC)运用于肿瘤化疗患者38 (男29,女9)例,年龄35~73(平均41)岁. 其中肺癌17例,肝癌6例,乳腺癌9例,淋巴瘤5例,胃癌1例. 初发初治30例,反复化疗8例. 采用美国巴德公司生产的蓝色PICC导管,管长60 cm,管腔容积1 mL,以后采用美国Arrow公司生产的豪华装4Fr导管. 插管前紫外线消毒治疗室,光线应充足,并备好用于穿刺的物品. PICC穿刺包、无菌手套、碘酒、乙醇、医用棉签、皮尺、止血带、无菌肝素生理盐水、可莱福输液接头、20 mL注射器、静脉穿刺包、康乐保透明贴膜、Arrow豪华包.  相似文献   
160.
Diabetes is a common condition that is increasing in incidence worldwide. Although the skin manifestations of this condition are well described, there is scant literature on the associated nail changes. In this review, we describe the various clinical features of nail changes associated with diabetes, which can be broadly divided into infections, vascular changes, neuropathic manifestations and miscellaneous changes, although there is overlap between them. There is no pathognomonic nail alteration, but it is important for clinicians to be aware of the potential nail manifestations in diabetes as they can facilitate investigations and thereby early diagnosis of diabetes, resulting in holistic management of the patient.  相似文献   
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