全文获取类型
收费全文 | 500篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 4篇 |
建筑科学 | 12篇 |
轻工业 | 8篇 |
石油天然气 | 1篇 |
无线电 | 1篇 |
一般工业技术 | 1篇 |
冶金工业 | 471篇 |
原子能技术 | 1篇 |
自动化技术 | 2篇 |
出版年
2013年 | 1篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 4篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 5篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 15篇 |
1998年 | 124篇 |
1997年 | 75篇 |
1996年 | 40篇 |
1995年 | 27篇 |
1994年 | 23篇 |
1993年 | 33篇 |
1992年 | 4篇 |
1991年 | 11篇 |
1990年 | 12篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 13篇 |
1985年 | 8篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 15篇 |
1976年 | 30篇 |
1975年 | 2篇 |
1974年 | 1篇 |
排序方式: 共有501条查询结果,搜索用时 15 毫秒
71.
Functional analysis of a transactivation domain in the thyroid hormone beta receptor 总被引:1,自引:0,他引:1
Y Tone TN Collingwood M Adams VK Chatterjee 《Canadian Metallurgical Quarterly》1994,269(49):31157-31161
72.
EM De Vries DO Ricke TN De Vries A Hartmann H Blaszyk D Liao T Soussi JS Kovach SS Sommer 《Canadian Metallurgical Quarterly》1996,7(3):202-213
Germline and somatic mutations in the p53 and APC genes contribute to neoplasia. The patterns of these and other acquired mutations in cancers reflect environmental mutagens and endogenous factors that contribute to carcinogenesis. Herein, we describe a database of almost 2,300 mutations in the p53 and APC genes published until September 1, 1993. In addition to cataloging the mutations, multiple fields of information have been added to facilitate future molecular epidemiological analyses of human cancer. The accuracy of the database has been checked by the present authors and, by soliciting feedback from the original corresponding authors. The strengths and limitations of the primary literature are discussed. 相似文献
73.
Using tibiofemoral joints from older (age, 53-80 years) human cadavers with articular cartilage degeneration, contact pressures and contact areas were measured in the extended knee in four conditions: (1) neutral alignment; (2) 5 degrees varus (simulating single limb stance of gait); (3) 5 degrees valgus; and (4) after a 5 degrees proximal tibial closing wedge valgus osteotomy. In degenerated cartilage, contact pressures were reduced at the lesion sites and were high on the borders of the lesions. No statistically significant changes occurred in contact pressures and areas when values from neutral loading were compared with values during loading in each of the other three conditions. Lateral average and maximum contact pressures were less in varus loading than in valgus loading. Equal medial and lateral contact pressures during varus loading, in contrast to lower medial than lateral contact pressures in the other three loading, supports the theory that the varus moment imposed on the knee in single limb stance could be a mechanism causing medial tibiofemoral osteoarthritis. The 5 degrees valgus osteotomy resulted in contact pressures similar to those in neutral loading. These experiments do not support the value of the 5 degrees valgus osteotomy in reducing contact pressures on the medial tibial plateau. 相似文献
74.
JF Haeuw I Rauly L Zanna C Libon C Andreoni TN Nguyen T Baussant JY Bonnefoy A Beck 《Canadian Metallurgical Quarterly》1998,255(2):446-454
Klebsiella pneumoniae OmpA, the 40-kDa major protein of the outer membrane, was cloned and expressed in Escherichia coli. The recombinant protein was produced intracellularly in E. coli as inclusion bodies. Fusion of a short peptide to the N-terminus of native P40 facilitated high-level expression of the recombinant protein. Purified recombinant P40 was analyzed to verify purity and structural integrity. The molecular mass of purified recombinant P40 determined by electrospray mass spectrometry was 37,061 Da, in agreement with the theoretical mass deduced from the DNA sequence. Specific proliferation of recombinant-P40-primed murine lymph node cells in response to recombinant P40 stimulation in vitro indicated the presence of a T-cell epitope on recombinant P40. The induction of high serum antibody titers to a synthetic peptide derived from the attachment protein G of the respiratory syncytial virus when chemically coupled to recombinant P40 indicated that the protein had potent carrier properties. 相似文献
75.
OV Semina TN Semenets VI De?gin AM Korotkov AM Poverenny? 《Canadian Metallurgical Quarterly》1993,116(9):298-299
Whether accessory T cells can be replaced by the synthetic immunomodulators thymogen (Glu-Trp) and thymohexin (Arg-Lys-Asp-Val-Tyr-Arg) was studied. The latter immunomodulator was found to show a 3-fold increase in splenic colony formation after incubation of bone marrow cells with rabbit antimouse brain serum (RAMBS). The former preparation failed to show the same action. Its effect was close to that of thymocytes. When the recipients exposed to lethal irradiation were administered the RAMBS-treated bone marrow cells and one of the peptides, it was shown that in concomitant administration, thymohexin and thymocytes lost their ability to restore colony formation by RAMBS-treated bone marrow. Thymogen did not suppress the stimulating activity of thymocytes. It is suggested that the differences observed between the tested peptides in their ability to recover colony formation were determined by their structure. 相似文献
76.
Seasonal variation in the capacity of bank voles, Clethrionomys glareolus (Schreber), to infect larval Ixodes ricinus (L.) ticks with Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner was examined from May through October 1991 at Bogesund, near Stockholm in south-central Sweden. Although larval infestations of bank voles were greatest in June and July, nearly 70% of all larval ticks infected with spirochetes by bank voles at this site became infected during August and September. Seasonality of infectivity was related to the degree of earlier nymphal infestation on voles as well as to the age composition of the vole population. These factors may influence the infectivity of other rodent reservoirs of B. burgdorferi, both in Europe and North America. Moreover, in determining the reservoir potential of tick hosts, a host population's spirochetal infectivity should be determined for the entire period of larval infestation rather than just during the period of peak larval infestation. 相似文献
77.
78.
OBJECTIVE: To examine the incidence of invasive cervical cancer per 100,000 women years at risk and relative risk according to screening history among eligible women aged 25-69 in Southampton and South West Hampshire during the three years after completion of the first round of comprehensive screening. RESULTS: There was a significantly higher incidence of invasive cervical cancer in women who had not been screened during the preceding 0.5-5.5 years than in those who had been screened (relative risk (RR) 2.6; 95% confidence interval (CI) 1.6 to 4.3). Among the latter group of women (with interval cancers) there was a significantly higher incidence in those with a long interval of 3.5-5.5 years since their most recent smear than in those with a short interval of 0.5-3.5 years (RR 2.2; 95% CI 1.3 to 3.8). Among women with non-interval cancers, there was a significantly higher incidence among those who had no cytology record than among those who had been screened but were overdue for a smear (RR 3.0; 95% CI 1.2 to 7.3). When screen detected cancers were excluded from the figures the relative risks for all the comparative groups described above were greater, though the 95% confidence limits were wider because the numbers were smaller. The most pronounced difference in incidence was between symptomatic cancers in women with a short screening interval (5.8 per 100,000 women years at risk) and in women with no cytology record (71.3 per 100,000 years at risk). Most cancers were interval cancers (76%) because of the high screening coverage: 89.2% of eligible women aged 25-69 had been screened during the preceding 0.5-5.5 years. The overall incidence per 100000 women years at risk approached that of interval cancers, and was nearer to that observed in the short than the long interval because 74.7% of women had been screened within 3.5 years. CONCLUSION: The results confirm the effectiveness of screening but suggest that a five year screening interval may be too long, at least during the early rounds of screening. 相似文献
79.
The authors show that intensification of peloid therapy, i.e. more frequent procedures, in patients with pulmonary diseases imposes additional load on the regulatory systems: vegetative, cardiovascular, immune. Moderate balneological reactions become more frequent, therapeutic results worsen. How to correct the above negative effects is proposed. 相似文献
80.
The effect of leaf decoctions of three plants of the Pyrolaceae family, namely, umbrella wintergreen, one-side ortilia, and round-leaf Pyrola was studied in rat experiments. All plants under study were found to contain approximately equal amounts of tannins and arbutin glycoside. Their concentration was comparable though rather lower than in common bearberry, a well-known plant with diuretic and antiseptic activity. When given for a long time, all Pyrolaceae increased urination and sodium excretion. Besides, their decoctions caused an antimicrobial effect. Only round-leaf Pyrola weakened the development of experimental inflammation. Its anti-inflammatory effect was probably due the presence of flavonoids the content of which in Pyrola was maximum. 相似文献