全文获取类型
收费全文 | 1938篇 |
免费 | 5篇 |
专业分类
化学工业 | 5篇 |
轻工业 | 7篇 |
水利工程 | 1篇 |
无线电 | 2篇 |
一般工业技术 | 3篇 |
冶金工业 | 1924篇 |
自动化技术 | 1篇 |
出版年
2022年 | 1篇 |
2019年 | 1篇 |
2015年 | 5篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2010年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2003年 | 3篇 |
1999年 | 64篇 |
1998年 | 567篇 |
1997年 | 356篇 |
1996年 | 238篇 |
1995年 | 120篇 |
1994年 | 94篇 |
1993年 | 121篇 |
1992年 | 12篇 |
1991年 | 24篇 |
1990年 | 12篇 |
1989年 | 18篇 |
1988年 | 20篇 |
1987年 | 13篇 |
1986年 | 17篇 |
1985年 | 13篇 |
1983年 | 3篇 |
1982年 | 8篇 |
1981年 | 10篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 5篇 |
1977年 | 62篇 |
1976年 | 124篇 |
1975年 | 6篇 |
1972年 | 1篇 |
1965年 | 1篇 |
1963年 | 1篇 |
1955年 | 2篇 |
1954年 | 1篇 |
排序方式: 共有1943条查询结果,搜索用时 8 毫秒
1.
BB Horswell CL Castiglione AE Poole LA Assael 《Canadian Metallurgical Quarterly》1993,51(2):145-9; discussion 149-50
The double-reversing Z-plasty of Furlow for closure of the soft palate was used in 34 children with various types of cleft palate. Mean age at repair was 12.8 months. Intraoperative experience was favorable, with acceptable operating time and blood loss. Length of hospitalization averaged 1.9 days. Postoperatively, two children experienced temporary stridor, which resolved within 24 to 48 hours. One child had dehiscence of the hard palate (Von Lagenbeck repair) 4 weeks postoperatively, and three children developed small oronasal fistulae. Early speech evaluation demonstrated adequate soft palate mobility in 33 of 34 patients, with observable velopharyngeal function. Twelve children had mild velar compromise, with eight exhibiting slight nasal air escape. 相似文献
2.
AE Speckens AM Van Hemert JH Bolk HG Rooijmans MW Hengeveld 《Canadian Metallurgical Quarterly》1996,26(4):745-752
BACKGROUND: Measurement of intracardiac hemodynamic parameters has been limited to brief periods in the acute care setting. We developed and evaluated an implantable hemodynamic monitor that is capable of measuring chronic right ventricular oxygen saturation and pulmonary artery pressure. METHODS AND RESULTS: The device consists of an electronic controller placed subcutaneously and two transvenous leads placed in the right ventricle (reflectance oximeter) and pulmonary artery (variable capacitance pressure sensor). Implantation was performed in 10 patients with severe left ventricular dysfunction. Average implant pulmonary artery pressures were systolic, 52 +/- 16 mm Hg; diastolic, 29 +/- 11 mm Hg; and mean, 40 +/- 12 mm Hg. The mean right ventricular oxygen saturation at implant was 51%. Provocative maneuvers, including postural changes, sublingual nitroglycerin, and bicycle exercise, demonstrated expected changes in measured oxygen saturation and pulmonary artery pressures over time. At follow-up of 0.5 to 15.5 months, there were no significant differences between pulmonary artery pressures or oxygen saturation values transmitted from the device and simultaneous measurement with balloon flotation catheters. Four of the pulmonary artery leads dislodged and three demonstrated sensor drift, whereas two of the oxygen saturation sensors failed. Four patients died and four received transplants. Pathological study did not demonstrate injury to the right ventricular outflow tract or pulmonic valve. CONCLUSIONS: Chronic measurement of hemodynamic parameters in the outpatient setting with implantable sensor technology appears to be feasible. The devices are well tolerated without significant untoward effects, and the sensors generally function well over time, providing reliable information. Clinical usefulness remains to be established. 相似文献
3.
4.
A questionnaire to evaluate the needs of dialytic patients and the burden that these have on the health service and staff, was formulated by the nurses. The results showed how the patient's case history indicate, significantly, not only personal and subjective aspects (e.g. interpersonal relationships), but also how they construct their relationships with the hospital and its service (including the hospital staff). This opens up certain reflections on what role communication and information play within the hospital structure. 相似文献
5.
6.
7.
8.
AE Segelman 《Canadian Metallurgical Quarterly》1997,45(4):16, 20-16, 22
9.
E Gürdal-Yüksel M Karada? N Ozyardimci AE Kunt-Uzaslan T Yarkin 《Canadian Metallurgical Quarterly》1996,15(2-4):161-167
The purpose of our study was to evaluate the effects of cigarette smoking and serum lipids, folate, and vitamin B12 on the development of lung cancer in the Turkish population. The study group consisted of patients with histologically proven lung cancer and the control group comprised healthy smokers being followed in our smoking cessation outpatient department. Smoking history was obtained from all subjects and serum total cholesterol, HDL cholesterol, triglycerides, vitamin B12, and folate levels were measured. Pack/years of cigarettes smoked were significantly higher in the subjects with lung cancer than in the control group (p < 0.01). Serum total cholesterol, HDL cholesterol, triglyceride, serum folate, and vitamin B12 levels were within normal limits in both groups (p < 0.05), but serum vitamin B12 levels were statistically significantly higher (p < 0.01) in the cancer group than in the controls. In our study, we did not observe low levels of serum cholesterol, vitamin B12, or folate in the lung cancer patients. 相似文献
10.