全文获取类型
收费全文 | 1885篇 |
免费 | 82篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 33篇 |
妇产科学 | 18篇 |
基础医学 | 210篇 |
口腔科学 | 32篇 |
临床医学 | 197篇 |
内科学 | 399篇 |
皮肤病学 | 30篇 |
神经病学 | 115篇 |
特种医学 | 133篇 |
外科学 | 448篇 |
综合类 | 20篇 |
预防医学 | 134篇 |
眼科学 | 5篇 |
药学 | 60篇 |
中国医学 | 3篇 |
肿瘤学 | 112篇 |
出版年
2021年 | 12篇 |
2020年 | 19篇 |
2019年 | 20篇 |
2018年 | 23篇 |
2017年 | 20篇 |
2016年 | 22篇 |
2015年 | 21篇 |
2014年 | 33篇 |
2013年 | 63篇 |
2012年 | 57篇 |
2011年 | 64篇 |
2010年 | 45篇 |
2009年 | 57篇 |
2008年 | 83篇 |
2007年 | 87篇 |
2006年 | 72篇 |
2005年 | 74篇 |
2004年 | 69篇 |
2003年 | 77篇 |
2002年 | 68篇 |
2001年 | 47篇 |
2000年 | 62篇 |
1999年 | 52篇 |
1998年 | 47篇 |
1997年 | 31篇 |
1996年 | 38篇 |
1995年 | 30篇 |
1994年 | 35篇 |
1993年 | 31篇 |
1992年 | 43篇 |
1991年 | 46篇 |
1990年 | 45篇 |
1989年 | 36篇 |
1988年 | 44篇 |
1987年 | 32篇 |
1986年 | 41篇 |
1985年 | 36篇 |
1984年 | 24篇 |
1983年 | 22篇 |
1982年 | 22篇 |
1980年 | 14篇 |
1979年 | 27篇 |
1978年 | 19篇 |
1977年 | 16篇 |
1976年 | 21篇 |
1975年 | 13篇 |
1974年 | 15篇 |
1973年 | 14篇 |
1972年 | 12篇 |
1967年 | 19篇 |
排序方式: 共有1981条查询结果,搜索用时 62 毫秒
101.
Autogenous buccal mucosa and cortical bone were transplanted in a one-stage procedure to an anterior tracheal defect in 5 beagles. The result was studied by endoscopy, light microscopy, scanning electron microscopy and transmission electron microscopy. The bone graft was shaped as an oval disc and perforated with large holes for vascular nutrition of the mucosal graft. Small holes were made along the periphery for suturing the buccal mucosa to the bone disc and for suturing the composite graft to the tracheal defect. The mucosa sloughed off from the framework during the first 2 weeks and the bone graft was subsequently expelled through the airway. The mucosal graft was replaced by ciliated columnar epithelium supported by firm connective tissue. Various surface structures were found in the regenerating epithelium. Although the animals did not suffocate or develop a stenosis, this procedure cannot in its present form be recommended for use in clinical practice. 相似文献
102.
103.
Luukkaa M Aitasalo K Pulkkinen J Lindholm P Valavaara R Grénman R 《Acta oto-laryngologica》2002,122(3):318-322
The aim of this study was to evaluate the usefulness of a contact neodymium YAG laser for the treatment of squamous cell carcinoma (SCC) of the mobile tongue in 35 patients. The TNM stage and histologic grade were as follows: T1, n = 20; T2, n = 11; T3, n = 4; and N0, n = 33; N1, n = 2; G1, n = 20; G2, n = 10; and G3, n = 5. The surgical treatment consisted of a hemiglossectomy or resection with adequate margins in 28 cases, and an ipsilateral neck dissection was also performed in 7 patients. Radiotherapy to a mean tumor dose of 62-64 Gy and an elective dose of 50 Gy to the cervical lymph nodes was given to 14 patients. The radiotherapy was preoperative in 12 patients and postoperative in 2. Tongue resection was easily performed using the contact neodymium YAG laser, with a mean operation time of 31 min and intraoperative bleeding varying from negligible to 100 cm3. During postoperative follow-up no major complications occurred: cases with minor hemorrhage were easily controlled on the ward and 1 patient had a bleed on the 14th postoperative day necessitating hospitalization. The resection was histologically radical in all cases. During follow-up one patient had a local recurrence (T2N0, G3) and four failed in the neck (T1N0 G2, T1N0 G2, T1N0 G2, T2N0 G2), three of whom were successfully salvaged with a neck dissection and radiotherapy. One patient with osteoradionecrosis was diagnosed and treated curatively. Two patients died of their tongue cancer (T2N0 G3, T2N0 G2), 1 died from a second primary tumor (T2N0 G1) and 2 of intercurrent disease with no evidence of cancer; 30 patients (86%) are still alive with no evidence of disease. The function of the tongue in all patients in this sample was good to satisfactory. The major complaint was xerostomia in the irradiated patients. In conclusion, the contact neodymium YAG laser appears to be suitable for resection of T1-T2 SCCs of the oral tongue. In this limited patient sample T stage or grade did not predict failures in the neck. Biologic predictive markers need to be evaluated. 相似文献
104.
105.
Cost-effectiveness of different caries preventive measures in a high-risk population of Swedish adolescents 总被引:2,自引:0,他引:2
Oscarson N Källestål C Fjelddahl A Lindholm L 《Community dentistry and oral epidemiology》2003,31(3):169-178
OBJECTIVES: A total of 3373 12-year-olds agreed to participate in an intervention study evaluating different caries preventive measures. The study, titled 'Evaluation of caries preventive measures', was performed between 1995 and 1999 at 26 dental health clinics throughout Sweden. At the start of the study, the subjects were classified as individuals at high or low risk of developing caries. The high-risk group consisted of 1165 subjects. The children in the high-risk group were randomly assigned to one of four preventive programs. The programs represent a step-wise increase in fluoride content, contact with dental personnel and cost. The aim of the present cost-effectiveness analysis (CEA) study performed from a societal perspective is to compare costs and consequences of caries preventive programs in a caries high-risk population. By 'costs' is meant both treatment costs and costs contributed by the patient and the patient's family. Costs contributed by patients and their families consist of out-of-pocket expenses, transportation costs, and time. Conclusions are that it is important to consider the perspective from which a study is carried out. Costs contributed by the patient and the patient's family have a high impact on total costs for children and younger adolescents but decrease with time as the adolescents get older. The present study shows an incremental cost-effectiveness of 2043 SEK (8.54 SEK = 1 US dollar, December 1999) per averted decayed enamel and dentine missing and filled surface (DeMFS), of which treatment costs represent 1337 SEK using the unit cost for a nurse. This means a yearly cost of approximately 334 SEK. 相似文献
106.
107.
Heat sterilization of peritoneal dialysis solutions influences ingestive behavior in non-uremic rats
Zheng ZH Anderstam B Qureshi AR Heimbürger O Wang T Södersten P Bergström J Lindholm B 《Kidney international》2002,62(4):1447-1453
BACKGROUND: The appetite inhibitory effect of glucose-based peritoneal dialysis (PD) solutions may be due to glucose as such, or the hyperosmolality of the PD solution, or an effect of glucose degradation products (GDPs) formed in the PD solution during heat sterilization. This was studied in an experimental appetite model in rat. METHODS: The effect of different experimental PD solutions on ingestive behavior was investigated in non-uremic rats equipped with an implanted intraoral (i.o.) cannula through which a 1 mol/L sucrose solution was infused during tests. The amount of intake was recorded at 30 min after rats were infused intraperitoneally (IP) with 30 mL of different solutions. This method allowed an accurate and reproducible analysis of i.o. intake. The experimental PD solutions tested included (1) glucose based PD solutions with different glucose concentrations, sterilized by heat or microbiological filter, (2) glucose- and mannitol-based PD solutions with the same osmolality, sterilized by heat or microbiological filter; and (3) glucose based PD solutions, using different pH values (pH 3.0, pH 5.5 or pH 7.4) during heat sterilization. RESULTS: Following IP infusion of solutions, (1) the i.o. intake was significantly inhibited by glucose based, heat sterilized PD solutions and the degree of appetite suppression was related to the concentration of dialysate glucose in a dose-dependent way; (2) the i.o. intake was significantly less suppressed by filter sterilized than by heat sterilized glucose-based solutions; (3) the i.o. intake was significantly less following the IP infusion of glucose-based than following the mannitol-based heat sterilized solutions; however, i.o. intake did not differ between the glucose-based and mannitol-based filter sterilized solutions; and (4) furthermore, the degree of suppression of i.o. intake induced by glucose-based PD solutions was influenced by the pH value during heat sterilization. The lower the pH of the PD solution during heat sterilization, the higher the i.o. intake. CONCLUSIONS: The IP infusion of glucose-based heat-sterilized PD solutions inhibited food intake in this experimental appetite model, and the degree of suppression depended on the concentration of dialysate glucose and the pH of the solution during heat sterilization. The results suggest that GDPs formed during heat sterilization may exert a more adverse effect than glucose itself on ingestive behavior, and that a reduction of the concentration of GDPs in the PD solution using filter sterilization or a low pH value in the PD solution during heat sterilization may improve food intake. 相似文献
108.
109.
Lindholm S Ploj K Franck J Nylander I 《Progress in neuro-psychopharmacology & biological psychiatry》2002,26(2):303-306
The aim of this study was to study short- and long-term effects of repeated ethanol administration on nociceptin/orphanin FQ (N/OFQ) tissue concentrations in rat brain with radioimmunoassay. Animals were given either ethanol (intraperitoneal) or saline for 13 consecutive days. N/OFQ levels were examined at 30 min, 5 days and 21 days after the last dose on day 13. Ethanol-treated rats had significantly decreased N/OFQ tissue concentration in the hippocampus at 30 min after the last dose. N/OFQ levels were decreased in the cingulate cortex at 5 days after cessation of ethanol administration whereas no significant changes were found at 21 days. There were no significant changes in N/OFQ tissue concentrations at any time point studied in the mesolimbic dopamine (DA) system, a brain area associated with ethanol-induced activation. However, the results indicate that repeated ethanol administration may induce short- and long-term changes in N/OFQ tissue concentrations in other brain regions innervated with dopaminergic neurons. 相似文献
110.
Cohn-Cedermark G Rutqvist LE Andersson R Breivald M Ingvar C Johansson H Jönsson PE Krysander L Lindholm C Ringborg U 《Cancer》2000,89(7):1495-1501
BACKGROUND: Large, prospective, randomized trials with long term follow-up are required to obtain an unbiased evaluation of the significance of resection margins in patients with cutaneous melanoma. METHODS: The Swedish Melanoma Study Group performed a prospective, randomized, multicenter study of patients with primary melanoma located on trunk or extremities and with a tumor thickness > 0.8 mm and = 2 mm. Patients were allocated randomly to a 2-cm excision margin or a 5-cm excision margin. In total, 989 patients were recruited during the period 1982-1991. The median follow-up was 11 years (range, 7-17 years) for estimation of survival and 8 years (range, 0-17 years) for evaluation of recurrent disease. RESULTS: The crude rate of local recurrence, defined as a recurrence in the scar or transplant, was < 1% (8 of 989 patients). Twenty percent of the patients (194 of 989 patients) experienced any disease recurrence, and 15% (146 of 989 patients) died of melanoma. There were no statistically significant differences between the two treatment arms. In a multivariate Cox analysis with patients allocated to wide excision as the reference group, the estimated relative hazards for overall survival and recurrence free survival among those allocated to a 2-cm resection margin were 0.96 (95% confidence interval, 0.75-1.24), and 1.02 (95% confidence interval, 0.80-1.30), respectively. CONCLUSIONS: In this long term follow-up study, local recurrences were found to be rare among patients with tumors > 0.8 mm thick and = 2.0 mm thick. No difference in recurrence rate or survival between the two treatment groups was found. Patients in this category can be treated with a resection margin of 2 cm as safely as with a resection margin of 5 cm. 相似文献