全文获取类型
收费全文 | 797篇 |
免费 | 1篇 |
专业分类
化学工业 | 1篇 |
能源动力 | 1篇 |
轻工业 | 1篇 |
无线电 | 7篇 |
一般工业技术 | 4篇 |
冶金工业 | 755篇 |
自动化技术 | 29篇 |
出版年
2019年 | 1篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2014年 | 1篇 |
2013年 | 4篇 |
2012年 | 1篇 |
2011年 | 2篇 |
2009年 | 7篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 14篇 |
1998年 | 193篇 |
1997年 | 110篇 |
1996年 | 78篇 |
1995年 | 43篇 |
1994年 | 41篇 |
1993年 | 39篇 |
1992年 | 7篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 9篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 13篇 |
1980年 | 13篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1977年 | 66篇 |
1976年 | 93篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有798条查询结果,搜索用时 15 毫秒
41.
Imaging features and clinical significance of perineural spread or extension of head and neck tumors
KS Caldemeyer VP Mathews PD Righi RR Smith 《Canadian Metallurgical Quarterly》1998,18(1):97-110; quiz 147
Perineural spread of head and neck tumors is a form of metastatic disease in which tumor disseminates to noncontiguous regions along the endoneurium or perineurium. Both computed tomography (CT) and magnetic resonance (MR) imaging can help detect perineural spread, although MR imaging is the modality of choice because of its multiplanar capability, its superior soft-tissue contrast, and the decreased amount of artifact from dental hardware. Perineural spread most commonly occurs in adenoid cystic carcinoma and squamous cell carcinoma. Nerve enlargement may lead to foraminal enlargement and, ultimately, to foraminal destruction, findings that are best seen at CT. Extension through the foramen ovale and involvement of the Meckel cave is best seen on coronal T1-weighted MR images, and nerve enhancement is best seen on fat-suppressed T1-weighted MR images. Other radiologic findings include obliteration of fat planes at foraminal openings, neuropathic atrophy, cavernous sinus enlargement, and replacement of the trigeminal subarachnoid cistern with soft tissue. The pathway of perineural tumor spread is predictable with knowledge of the pertinent cranial nerve anatomy; however, patients with radiologically or pathologically proved perineural spread may have normal nerve function at clinical examination. Therefore, it is imperative that the radiologist be familiar with both normal cranial nerve anatomy and the radiologic appearance and assessment of perineural tumor extension. 相似文献
42.
43.
VA Kholodny? IF Syrbu MM Militsa VP Kovalenko VO Zhulin'sky? OV Kapshytar 《Canadian Metallurgical Quarterly》1997,(11-12):10-11
While examination of 83 patients it was established that in the presence of complicated gastric and duodenal ulcer disease the secondary immune deficiency is developing, which deepens after the surgical intervention conduction. Tiotriazolin, promoting the immune system state and the blood biochemistry indexes normalization, the immune system state and the blood biochemistry indexes stimulation, hemopoiesis stimulation, the treatment results improvement, was applied for immunomodulation. 相似文献
44.
45.
EI Nikolaeva EA Oteva VP Leutin AB Maslennikov LP Osipova AA Nikolaeva 《Canadian Metallurgical Quarterly》1995,52(3):207-211
In neonates and infants, hearing impairment leads to impaired language and cognitive development. For that reason, early detection of this sensory deficit is of outstanding importance, particularly in pre-term neonates, who constitute a high risk population in regard to very early acquired hearing loss. Evoked (EOAE) and spontaneous otoacoustic emission (SOAE) recording in 93 pre-term and full-term neonates revealed that this technique is potentially useful for auditory screening in neonatology units. EOAEs and SOAEs can be recorded successfully from 30 weeks of conceptional age. SOAEs were found to be prevalent in females and presented higher peak numbers in right than in left ears. Furthermore, SOAE incidence in pre-term and full-term neonates was found to be high in EOAE positive ears, associated with strong and robust EOAEs. 相似文献
46.
OI Potrokhov DV Dolgikh VP Kas'ianovskaia OI Shevchenko 《Canadian Metallurgical Quarterly》1997,(7):14-18
The study covered influence of combined toxic chemicals on fire extinguishers. Acute exposure of respiratory and peripheral nervous systems was demonstrated. Consequences of the exposure were proved to include polyneuropathies, neuroses and other health disorders. 相似文献
47.
Restriction fragment length polymorphism (RFLP) of the apolipoprotein B locus was investigated in the population of Tomsk. The frequencies of alleles and haplotypes of polymorphic restriction sites XbaI, MspI, and EcoRI were determined. The parameters of linkage disequilibrium and polymorphism information content (PIC) were estimated. Comparative data on various regions of the world are shown. 相似文献
48.
MG Tvorogova VP Lupanov EIu Nuraliev TM Za?tseva VV Kukharchuk VN Titov 《Canadian Metallurgical Quarterly》1998,70(8):17-21
AIM: Evaluation of effectiveness of hypolipidemic action of probucol in doses 500 and 1000 mg/day and comparison of probucol blood concentrations on the treatment month 3 and 6. MATERIALS AND METHODS: Probucol (Akrikhin, Russia) was given to 41 patients with primary hypercholesterolemia in a dose 500 mg/day. 3 months later the patients were divided into two groups. Group 1 patients exhibited a > 10% decrease in cholesterol levels and continued to take probucol in the dose 500 mg/day. Group 2 patients were crossed over to higher cholesterol dose--up to 1000 mg/day. Lipids levels were measured by enzyme tests, apoproteins--by immunoturbidimetry and immunodiffusion, probucol concentrations--by high-performance liquid chromatography. RESULTS: After 3 months of treatment, cholesterol lowered by 14.3 and 9.2% in groups 1 and 2, respectively. After 6 months, by 19.7 and 12.9%, respectively. Probucol concentrations in blood were higher after 6 months of treatment than after 3 months in both groups. No significant differences existed between the groups by probucol concentrations in 3 and 6 months. CONCLUSION: Hypolipidemic effect of probucol depended on the individual features of lipoproteins metabolic disorders rather than the drug blood concentration. Larger probucol doses fail to reduce cholesterol further. 相似文献
49.
TA Gudasheva SS Boyko VKh Akparov RU Ostrovskaya SP Skoldinov GG Rozantsev TA Voronina VP Zherdev SB Seredenin 《Canadian Metallurgical Quarterly》1996,391(1-2):149-152
Using high-performance liquid chromatography, gas-chromatography and chromato-mass spectrometry methods a novel endogenous cyclic dipeptide cyclo-prolylglycine was identified in rat brain. Its content according to gas chromatography is 2.8 +/- 0.3 nmol/g wet brain. Synthetic cyclo-prolylglycine has demonstrated antiamnesic activity in the passive avoidance test in rats at a dose of 0.1 mg/kg i.p. Cyclic dipeptide cyclo-prolylglycine seems to be a memory facilitating substance and its presence in rat brain suggests the existence of a new mechanism of memory regulation. 相似文献
50.
STUDY OBJECTIVE: To determine the agreement between rectal temperature and infrared tympanic membrane temperatures in marathon runners presenting to a field hospital at the finish line. METHODS: The subjects of this prospective, blinded, controlled study were runners 18 years or older who were triaged to the acute care medical area at the finish line for suspected hypothermia, hyperthermia, dehydration, or altered mental status. Rectal and tympanic temperatures were measured simultaneously in all subjects for whom rectal temperature measurement had been deemed necessary and recorded on separate data cards. RESULTS: Of the 239 runners treated in the acute care medical area, 37 required rectal temperature measurement and were enrolled in the study. The mean rectal temperature was 38.45 degrees +/- 1.20 degrees C (range, 35.9 degrees to 41.5 degrees C). The mean tympanic membrane temperature was 37.81 degrees +/- 95 degrees C (range, 36.3 degrees to 40.4 degrees C). Pearson's correlation coefficient revealed a moderate correlation (r = .6902, P = .00023). The mean temperature difference between the two thermometers, mean rectal minus mean tympanic membrane, was .64 degrees C (95% confidence interval, .35 degrees to .93 degrees C). Sixty-Two percent of the tympanic membrane readings were within 1 degree C of their rectal counterparts. Agreement ranged from 1.16 degrees (+2 SD) to -2.95 degrees (-2 SD). The 95% confidence interval was 1.67 degrees to -2.95 degrees C. CONCLUSION: We were able to demonstrate only a moderate correlation between the two thermometer readings, with a wide spread between the limits of agreement. This spread could be clinically significant and therefore limits the usefulness of tympanic temperature in the marathon race setting. Because of the potentially large and clinically significant differences in rectal and tympanic temperatures and the limitations inherent in our study, we cannot endorse the use of tympanic temperature in the setting of a marathon event. 相似文献