全文获取类型
收费全文 | 2046篇 |
免费 | 0篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 6篇 |
机械仪表 | 1篇 |
轻工业 | 3篇 |
石油天然气 | 1篇 |
无线电 | 4篇 |
一般工业技术 | 2篇 |
冶金工业 | 2024篇 |
自动化技术 | 4篇 |
出版年
2015年 | 1篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 2篇 |
2010年 | 1篇 |
2009年 | 1篇 |
2007年 | 4篇 |
2004年 | 1篇 |
2003年 | 3篇 |
1999年 | 81篇 |
1998年 | 650篇 |
1997年 | 354篇 |
1996年 | 226篇 |
1995年 | 142篇 |
1994年 | 114篇 |
1993年 | 110篇 |
1992年 | 17篇 |
1991年 | 14篇 |
1990年 | 14篇 |
1989年 | 23篇 |
1988年 | 21篇 |
1987年 | 24篇 |
1986年 | 19篇 |
1985年 | 19篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 14篇 |
1980年 | 13篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1977年 | 62篇 |
1976年 | 91篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1968年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有2046条查询结果,搜索用时 1 毫秒
31.
A new type of non-isotopic immunoassay, applied to the determination of serum gentamicin, is reported. The method is based on partial quenching of fluorescence observed when fluorescein-labelled gentamicin is bound by anti-gentamicin serum. The fluorescence intensity of the labelled gentamicin in an unseparated immunoassay incubation mixture therefore serves to indicate the extent of binding, which is related to the amount of competing unlabelled gentamicin present. Precision and accuracy are shown to be similar to those of the best existing methods for gentamicin, while the new assay is more rapid and technically simpler, and avoids the use of expensive radio-chemicals with their attendant health hazard. Assays of patient samples correlate with established bioassay and polarisation fluoroimmunoassay methods. 相似文献
32.
33.
Protein shedding, or the proteolytic cleavage of a protein from the surface of a cell, is emerging as an important mechanism in the regulation of cellular activity but it is poorly understood. Growing evidence suggesting that protein shedding and protein function are closely linked may lead to new strategies for the treatment of a wide range of diseases. 相似文献
34.
AS Lages KC Silva AL Miranda CA Fraga EJ Barreiro 《Canadian Metallurgical Quarterly》1998,8(2):183-188
OBJECTIVE: To study the effect of adjuvant chemotherapy after curative hepatic resection in patients with hepatocellular carcinoma. DESIGN: A randomized controlled trial. SETTING: A tertiary referral center. PATIENTS: During a 54-month period, 142 patients with hepatocellular carcinoma underwent hepatic resection at 1 institution. Sixty-six patients who survived the operation and had no demonstrable evidence of residual disease on ultrasonographic examination and hepatic angiographic testing at 1 month after surgery agreed to participate in the study. The median follow-up time was 28.3 months. INTERVENTION: Thirty patients received a combination of intravenous epirubicin hydrochloride (8 doses of 40 mg/m2 each at 6-week intervals) and transarterial chemotherapy using an emulsion of iodized oil and cisplatin (3 courses with a maximum dose of 20 mL each at 2-month intervals). Thirty-six patients had no adjuvant treatment. MAIN OUTCOME MEASURES: Recurrence rate and disease-free survival. RESULTS: A total of 138 courses of intravenous epirubicin was given to the 30 patients. Sixty-one courses of transarterial chemotherapy were given to only 29 of the 30 patients assigned to the treatment group, because the hepatic artery in 1 patient was thrombosed. Six patients (20%) had chemotherapy-related complications with no mortality. Twenty-three of 30 patients in the treatment group and 17 of 36 patients in the control group had recurrences (P=.01). Patients who received adjuvant chemotherapy had a higher incidence of extrahepatic metastases (11 patients vs 5 patients; P=.03). The respective disease-free survival rates at 1, 2, and 3 years were 50%,36%, and 18% for the treatment group and 69%, 53%, and 48% for the control group (P=.04). CONCLUSION: In a group of patients who underwent curative resection of hepatocellular carcinoma, postoperative adjuvant chemotherapy using the present regimen was associated with more frequent extrahepatic recurrences and a worse outcome. 相似文献
35.
36.
37.
A system is described which enables crosswords to be automatically compiled or solved, or which alternatively may assist in their manual compilation or solution. Illustrative examples are quoted and the performance of the system, which has been written for an Acorn BBC model B microcomputer with disc pack and printer, is discussed. 相似文献
38.
The time course of skin tumor induction was determined in hair-clipped inbred agouti C3Hf mice irradiated three times per week with a medium-pressure quartz-mercury lamp; 4 different UV doses were used. Although the ears were also exposed to the radiation, in the 3 groups given the highest doses no ear tumors were observed by the time each animal had developed at least 1 tumor on its back. No tumors were found in the animals receiving the lowest UV dose. In the group receiving the highest dose, males developed tumors earlier than did females; this trend continued in the lower dose groups. Many tumors that developed in the back skin were well-differentiated squamous cell carcinomas. Others were less well-differentiated squamous cell carcinomas. Others were less well defined so that the cell of origin was difficult to determine. In the group receiving the highest UV dose, the squamous cell carcinomas were few, whereas at the lower doses they predominated. 相似文献
39.
40.
Since the inception of mobile coronary care units (MCCU), patients with sudden cardiac death (SCD) saved by advanced emergency medical technicians (EMT-A) can be studied retrospectively and prospectively. Forty-eight cases of SCD found in ventricular fibrillation (VF) were successfully resuscitated. Only 32% had a myocardial infarction. Most survivors were New York Heart Association (NYHA) class I or II. All class IV survivors with severe congestive heart failure died within 45 days. All class II survivors had angina as the limiting factor. Of all patients with VF, 23% survived. Eighty percent of survivors were class I or II and have resumed previous lifestyles. No clear cut symptom complex was identified. Rescue response time was generally less than five minutes. Intracardiac medications were administered without complications. Empirical administration of sodium bicarbonate correlated poorly with arterial blood gas determinations. 相似文献