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81.
JA Frank RE Hoffman JM Mann JD Crowe AR Hinman 《Canadian Metallurgical Quarterly》1981,245(3):264-266
From Dec 23, 1978, through Jan 31, 1979, an outbreak of five laboratory-confirmed cases and four clinical cases of measles occurred in a Vietnamese refugee population living in a single housing complex in Albuquerque, NM. The index cases were in two refugee siblings in whom measles was incubating on arrival in the United States. Despite spread through three subsequent generations of disease transmission within the Vietnamese population, there was no additional spread into the general Albuquerque population. Responsible factors included the age distribution of susceptible persons, the social isolation of the refugee population, and the physical structure of the housing complex. There is a need to identify the problem of imported measles in "ethnic islands" in need of vaccination. 相似文献
82.
S Hatano MS Sadove DM Keane RE Boggs MA El-Naggar 《Canadian Metallurgical Quarterly》1976,25(10):457-463
Two hundred open heart cases anaesthetized with a combination of diazepam-ketamine using "Micro-Mini" drip administration technique were presented. The results were eminently desirable, and in the opinion of the authors are a notable improvement over other methods for all types of cardiovascular surgery including most advanced heart diseases. The advantages of this anaesthetic method for cardiovascular surgery are as follows: 1. Effects on cardiovascular system are minimal.--2. Respiratory depression is negligible.--3. There is no increase in salivation or muscle tone.--4. Induction and maintenance of anaesthesia are simple and smooth.--5. Anaesthesia can be maintained, using a high concentration of oxygen alone, by a slight increase in rate of ketamine administration whenever necessary.--6. Post-anaesthetic psychotomimetic effects are negligible.--7. Nearly 100% of patients have excellent amnesia.--8. It has a wide margin of safety.--9. This technique has proved highly acceptable to patients and surgeons. We feel ketamine should be used in small dosages continuously administered with either "Micro-Mini" drip infusion or infusion pump. Ketamine given in this fashion should be regarded as an analgesic. 相似文献
83.
S Hatano DM Keane RE Boggs MA El-Naggar MS Sadove 《Canadian Metallurgical Quarterly》1976,23(6):648-656
Two hundred open-heart cases were anaesthetized with a diazepam-ketamine combination. The results were excellent. A "Micro-Mini" drip technique insured low, even, but adequate dose levels of ketamine and less drug was used. Induction and maintenance are simple and smooth. Effects on the cardiovascular system and respiratory system are minimal. The margin of safety is wide and 100% oxygen can be used whenever needed. 相似文献
84.
85.
Ion beam enhanced deposition (IBED) was adopted to synthesize biocompatible titanium oxide film. Structure characteristics of titanium oxide film were investigated by RBS, AES, and XRD. The blood compatibility of the titanium oxide film was studied by measurements of blood clotting time and platelet adhesion. The results show that the anticoagulation property of titanium oxide film is improved significantly. The mechanism of anticoagulation of the titanium oxide film was discussed. 相似文献
86.
Thyroid cancer after exposure to external radiation: a pooled analysis of seven studies 总被引:1,自引:0,他引:1
E Ron JH Lubin RE Shore K Mabuchi B Modan LM Pottern AB Schneider MA Tucker JD Boice 《Canadian Metallurgical Quarterly》1995,141(3):259-277
The thyroid gland of children is especially vulnerable to the carcinogenic action of ionizing radiation. To provide insights into various modifying influences on risk, seven major studies with organ doses to individual subjects were evaluated. Five cohort studies (atomic bomb survivors, children treated for tinea capitis, two studies of children irradiated for enlarged tonsils, and infants irradiated for an enlarged thymus gland) and two case-control studies (patients with cervical cancer and childhood cancer) were studied. The combined studies include almost 120,000 people (approximately 58,000 exposed to a wide range of doses and 61,000 nonexposed subjects), nearly 700 thyroid cancers and 3,000,000 person years of follow-up. For persons exposed to radiation before age 15 years, linearity best described the dose response, even down to 0.10 Gy. At the highest doses (> 10 Gy), associated with cancer therapy, there appeared to be a decrease or leveling of risk. For childhood exposures, the pooled excess relative risk per Gy (ERR/Gy) was 7.7 (95% CI = 2.1, 28.7) and the excess absolute risk per 10(4) PY Gy (EAR/10(4) PY Gy) was 4.4 (95% CI = 1.9, 10.1). The attributable risk percent (AR%) at 1 Gy was 88%. However, these summary estimates were affected strongly by age at exposure even within this limited age range. The ERR was greater (P = 0.07) for females than males, but the findings from the individual studies were not consistent. The EAR was higher among women, reflecting their higher rate of naturally occurring thyroid cancer. The distribution of ERR over time followed neither a simple multiplicative nor an additive pattern in relation to background occurrence. Only two cases were seen within 5 years of exposure. The ERR began to decline about 30 years after exposure but was still elevated at 40 years. Risk also decreased significantly with increasing age at exposure, with little risk apparent after age 20 years. Based on limited data, there was a suggestion that spreading dose over time (from a few days to > 1 year) may lower risk, possibly due to the opportunity for cellular repair mechanisms to operate. The thyroid gland in children has one of the highest risk coefficients of any organ and is the only tissue with convincing evidence for risk about 1.10 Gy. 相似文献
87.
为了获得性能优良的耐热镁合金,研究了Sr对初生和共晶Mg_2Si相的变质作用,并利用扫描电子显微镜观察了Mg_2Si相的形貌特征与Mg-1.7Si-x Sr合金的微观组织.结果表明,当Sr的质量分数处于1.0%~1.5%范围内时,可对初生和共晶Mg_2Si相进行有效变质.Sr的吸附作用可以诱发孪晶沟槽、旋转晶界等原子扩展台阶的出现,引起原子堆砌方式和晶体生长方向的改变,因而Sr可对初生Mg_2Si相起到变质作用.Sr的添加还可将Mg+Mg_2Si共晶的长大方式由合作长大模式变为以重新形核为主兼有合作长大的混合模式,使得Mg_2Si相的生长形态产生改变,因而Sr可对共晶Mg_2Si起到变质作用. 相似文献
88.
89.
OBJECTIVE: Traditionally, barium paste has been used for performing defecography. Because this substance is not stool-like, barium defecography may not accurately represent defecatory function. Our aim was to prospectively compare the utility of a new artificial stool, "FECOM"--a silicon-filled and barium-coated, deformable device the shape and consistency of which mimicked a normal formed stool with that of barium paste. METHODS: Defecography was performed after placing FECOM or barium paste in a random order in 12 healthy subjects (two men and 10 women). We evaluated the changes in anorectal angle, rectal morphology, rectal sensation, and the subjects' preference for a "stool-like" device. RESULTS: Anorectal angle at rest, during squeeze, cough, and straining were each greater with the FECOM when compared with the barium paste (p < 0.006). Anterior rectocele (nine), mucosal intussusception (four), and incontinence (three) were identified only with barium defecography. Nine (75%) subjects preferred FECOM to barium paste (p < 0.001) and reported that expulsion of this device mimicked more closely their stools at home (p < 0.05). CONCLUSION: The anorectal angle is influenced by the form and consistency of stool material and is lower with barium paste. The detection of rectocele, mucosal intussusception, and barium leakage in normal subjects during barium defecography questions the significance of these findings. FECOM appears to be a realistic alternative to barium paste for performing defecography. 相似文献
90.
CA Rohl FA Boeckman C Baker T Scheuer WA Catterall RE Klevit 《Canadian Metallurgical Quarterly》1999,38(3):855-861
The sodium channel initiates action potentials by opening in response to membrane depolarization. Fast channel inactivation, which is required for proper physiological function, is mediated by a cytoplasmic loop proposed to occlude the ion pore via a hinged lid mechanism with the triad IFM serving as a hydrophobic "latch". The NMR solution structure of the isolated inactivation gate reveals a stably folded core comprised of an alpha-helix capped by an N-terminal turn, supporting a model in which the tightly folded core containing the latch motif pivots on a more flexible hinge region to occlude the pore during inactivation. The structure, in combination with substituted cysteine mutagenesis experiments, indicates that the IFM triad and adjacent Thr are essential components of the latch and suggests differing roles for the residues of the IFMT motif in fast inactivation. 相似文献