全文获取类型
收费全文 | 716篇 |
免费 | 62篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 45篇 |
妇产科学 | 42篇 |
基础医学 | 107篇 |
口腔科学 | 19篇 |
临床医学 | 43篇 |
内科学 | 156篇 |
皮肤病学 | 12篇 |
神经病学 | 83篇 |
特种医学 | 1篇 |
外科学 | 87篇 |
综合类 | 6篇 |
一般理论 | 1篇 |
预防医学 | 68篇 |
眼科学 | 8篇 |
药学 | 57篇 |
中国医学 | 1篇 |
肿瘤学 | 41篇 |
出版年
2024年 | 2篇 |
2023年 | 8篇 |
2022年 | 10篇 |
2021年 | 22篇 |
2020年 | 22篇 |
2019年 | 18篇 |
2018年 | 28篇 |
2017年 | 19篇 |
2016年 | 17篇 |
2015年 | 11篇 |
2014年 | 21篇 |
2013年 | 27篇 |
2012年 | 51篇 |
2011年 | 52篇 |
2010年 | 23篇 |
2009年 | 27篇 |
2008年 | 43篇 |
2007年 | 36篇 |
2006年 | 46篇 |
2005年 | 31篇 |
2004年 | 40篇 |
2003年 | 34篇 |
2002年 | 28篇 |
2001年 | 12篇 |
2000年 | 17篇 |
1999年 | 17篇 |
1998年 | 5篇 |
1997年 | 9篇 |
1996年 | 3篇 |
1993年 | 4篇 |
1992年 | 16篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 8篇 |
1988年 | 2篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1980年 | 2篇 |
1979年 | 4篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1974年 | 2篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1967年 | 2篇 |
1959年 | 1篇 |
1933年 | 2篇 |
排序方式: 共有783条查询结果,搜索用时 0 毫秒
1.
2.
Anya Pimentel Gomes Fernandes Vieira Jose Maria Sampaio Meneses Jr Renato Luiz Maia 《Journal of oral pathology & medicine》2007,36(2):117-119
Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details. 相似文献
3.
In a series of 11 melancholic patients who received both right unilateral and bilateral ECT during a single course of treatment, mean and minimum postictal heart rates were greater after bilateral ECT. Greater catecholamine release during bilateral ECT is the most likely explanation for these effects. These differences complement other evidence that bilateral ECT has a more pronounced physiological impact than unilateral ECT. 相似文献
4.
Delayed osteotomy but not fracture healing in pediatric osteogenesis imperfecta patients receiving pamidronate. 总被引:2,自引:0,他引:2
Craig Fj Munns Frank Rauch Leonid Zeitlin Fran?ois Fassier Francis H Glorieux 《Journal of bone and mineral research》2004,19(11):1779-1786
This study evaluated factors influencing fracture (n = 197) and osteotomy (n = 200) healing in children with moderate to severe OI. Pamidronate treatment was associated with delayed healing after osteotomy, but not after fracture. The data suggest that both pamidronate and mechanical factors influence bone healing in this cohort. INTRODUCTION: Intravenous pamidronate is widely used to treat children with moderate to severe osteogenesis imperfecta (OI). However, the effect of this treatment on bone healing is not well characterized. We therefore retrospectively analyzed the healing of lower limb fractures and osteotomies in children with moderate to severe OI, both before and after the start of pamidronate treatment. MATERIALS AND METHODS: Bone healing was evaluated on standard radiographs after 197 lower limb fractures (132 femur and 65 tibia) in 82 patients (age at fracture, 0.0-19.9 years) and 200 intramedullary rodding procedures in 79 patients (age at surgery, 1.2-19.8 years). Delayed healing was diagnosed when a fracture or osteotomy line was at least partially visible 12 months after the event. RESULTS: Delayed fracture healing was observed more frequently during than before pamidronate treatment. However, the effect of pamidronate was no longer significant when age differences were taken into account (odds ratio [OR], 1.76; 95% CI, 0.61-5.10). Better mobility status was a strong independent predictor of delayed healing after fractures that occurred during pamidronate treatment. After osteotomies, delayed healing was more frequent when pamidronate had been started before surgery (OR, 7.29; 95% CI, 2.62-20.3), and this effect persisted after adjustment for multiple confounders. During pamidronate treatment, older age (OR per year of age, 1.25; 95% CI, 1.06-1.47) and osteotomy of the tibia (OR, 3.51; 95% CI, 1.57-7.82) were independent predictors of delayed healing. CONCLUSIONS: This study suggests that pamidronate therapy is associated with delayed healing of osteotomy sites after intramedullary rodding procedures. Better mobility status, but not pamidronate treatment, seems to be predictive of delayed healing after fractures. 相似文献
5.
M F Zeitlin R Megawangi E M Kramer H C Armstrong 《The American journal of clinical nutrition》1992,56(1):136-147
The vitamin A intake of 370 mothers and 183 children 3-27 mo of age in rural Bangladesh was ascertained monthly from January to July in 1986. For mothers, dark green leafy vegetables and fruits were the main sources of vitamin A. Vitamin A from vegetables, the single most important source, did not show consistent associations with wealth or with the other socioeconomic indicators. In May and June, fruits provided wealthier (and more educated) mothers with significantly higher vitamin A intakes than poor mothers, whereas in January the poorer mothers had higher intakes. When breast milk was included, average intakes for children came close to 100% of the recommended dietary allowance; the only other significant source of vitamin A for children was seasonally available mangoes. Fourteen children who had stopped breast-feeding by the end of the study were at very high risk of vitamin A deficiency when fruits were not plentiful. 相似文献
6.
7.
Early-onset gastric carcinomas display molecular characteristics distinct from gastric carcinomas occurring at a later age 总被引:5,自引:0,他引:5
Carvalho R Milne AN van Rees BP Caspers E Cirnes L Figueiredo C Offerhaus GJ Weterman MA 《The Journal of pathology》2004,204(1):75-83
Gastric cancer is thought to result from a combination of environmental factors and accumulation of specific genetic alterations, and consequently mainly affects older patients (>50 years of age). Fewer than 10% of patients present with the disease before 45 years of age and these young patients are thought to develop carcinomas with a different molecular genetic profile from that of sporadic carcinomas occurring at a later age. Forty early-onset gastric carcinoma resection specimens were characterized for microsatellite instability (MSI) and loss of heterozygosity status using 22 polymorphic microsatellite markers. Twenty-four biopsies were additionally evaluated for the presence of MSI. No MSI was observed in any of the cases analysed. Losses were infrequent, but were most common for the D1S234 (26.1%) and D1S1676 (17.4%) markers, flanking the RUNX3 gene; for the p53ALU (23.1%) and TP53 (15.4%) markers, near the TP53 gene; and for the D16S2624 (17.2%) marker, near the E-cadherin (CDH1) gene. All cases with loss of CDH1, as well as 6/7 cases with loss of TP53, displayed aberrant staining of the corresponding proteins, pointing to a functional role for these proteins in early-onset gastric carcinogenesis. No germline CDH1, TP53 or RUNX3 mutations were detected in any of the cases analysed. No correlation was observed between non-functional E-cadherin and the histological type of the tumours analysed. Finally, Epstein-Barr virus was not detected in any of the cases analysed. On the basis of these results, early-onset gastric carcinomas appear to have characteristics distinct from gastric carcinomas occurring at a later age. 相似文献
8.
M E Egan M H Wagner P L Zeitlin W B Guggino 《American journal of respiratory cell and molecular biology》1992,7(5):500-506
Lipoxygenase metabolites influence ion movement and fluid balance in the airways. We studied the effects of nordihydroguaiaretic acid (NDGA), a general inhibitor of the lipoxygenase pathway, on Na+ and Cl- secretion in cultured tracheal epithelial cells from adult rabbits through short-circuit current (Isc) and radioactive tracer flux experiments. NDGA inhibition of leukotriene release in freshly isolated rabbit tracheal epithelial cells was assayed by a 3H peptidyl-leukotriene radioimmunoassay. 3 microM NDGA resulted in a 91% reduction of leukotriene release. In unstimulated cultures, Cl- secretion (furosemide-inhibited fraction of Isc) was 11.1 +/- 2.8 muamp/cm2 (n = 10) and was unchanged in the presence of NDGA (n = 10). Epinephrine-stimulated Cl- secretion increased Isc by 12.2 +/- 2 muamp/cm2 (n = 10). This stimulation was unchanged by pretreatment with NDGA (n = 10), suggesting that inhibition of the lipoxygenase pathway did not affect Cl- secretion. In unstimulated cultures, Na+ absorption (amiloride-inhibited portion of Isc) was 10.7 +/- 3.3. muamp/cm2 (n = 10) and was reduced by 79% in the presence of NDGA (n = 10), suggesting that inhibition of the lipoxygenase pathway was associated with inhibition of Na+ absorption. Radioactive tracer flux experiments supported these findings. Exogenous LTD4 (n = 7) and LTC4 (n = 7) were added to cells pretreated with NDGA, and Na+ absorption was restored to 76% and 70% of control, respectively. In addition, LTD4 (n = 4) and LTC4 (n = 4) were added to cells without prior inhibition of the lipoxygenase pathway to NDGA and resulted in an increase in Cl- secretion.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
10.
Brown LV Rogers BL Zeitlin MF Gershoff SN Huq N Peterson KE 《Ecology of food and nutrition》1993,30(2):99-126
Local market prices in rural Bangladesh were used to compute the costs of filling the nutrient gaps between actual intakes and safe nutrient requirements, and the costs of compliance with nutrition messages, for 78 lactating mothers and 61 weaning-age breastfed children. (The gap is the difference between the requirement and the amount of nutrient consumed.) To fill the mother's energy gap of approximately 1050 kcal (4393 kJ) would cost an additional 21% of the daily wage, or almost double the value of food she was presently eating. Given social reality, these costs would probably be much greater, as the mother would also need to increase the allocation of food to other household members. The weaning-age children's energy gap could theoretically be closed for less than one-third of the cost of improving the mothers' diets, or about 8% of the daily wage. The increase in food intake equivalent to 2% of the daily wage actually achieved through nutrition education resulted in a significant improvement in child weight gain, though not ideal. These findings suggest that, in the absence of programs which reduce economic barriers, it is economically feasible for families to close the nutrient gaps for weaning-age breastfed children in Bangladesh, but not for lactating women. Thus, education to improve women's diets should be incorporated into programs that make these improvements affordable, whereas education to improve weaning-age children's diets can be implemented with or without other program supports. 相似文献