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81.
We investigated interrelationships among stimulus classes established in matching-to-sample and sequence-production tasks. The analysis focused on the matching and sequencing of quantities, numerals, and arbitrary forms in two individuals with mental retardation. The basic protocol involved: (a) establishing both matching and sequencing performances with some stimuli, (b) training sequencing with a new set of stimuli and assessing whether new matching performances emerged, and (c) training matching with a new set of stimuli and assessing whether new sequencing emerged. The results showed that sequence training did not readily lead to new matching performances, unlike prior research with college students. In contrast, training in matching to sample yielded emergent sequence production; these data support prior studies involving children and adults without developmental disabilities. The results extend prior stimulus class research and suggest an important role for stimulus control processes in the production of generative numeric performances. 相似文献
82.
K Wright PJ Wilson J Kerr K Do T Hurst SK Khoo B Ward G Chenevix-Trench 《Canadian Metallurgical Quarterly》1998,17(9):1185-1188
BACKGROUND: Familial arteriolar tortuosity is an autosomal dominant disorder affecting the retinal arterioles. OBJECTIVES: To report a pedigree with this disorder and describe a systemic workup to determine whether this vascular abnormality is limited to the eye. RESULTS: A 58-year-old woman referred for retinal hemorrhages was found to have retinal arteriolar tortuosity of both eyes, especially in the macular area. Her 63-year-old brother had a history of retinal hemmorhages beginning at age 18 years and had similar fundoscopic examination findings. The proband had an extensive systemic workup, including magnetic resonance imaging, and cardiac and renal angiography, that failed to demonstrate any other sequelae of this inherited ocular syndrome. However, each member of the family expressing this phenotype did have hypertension. CONCLUSION: Inherited retinal arteriolar tortuosity is an autosomal dominant disorder limited to the eye, at least in this pedigree, within the sensitivity of the systemic workup we used. 相似文献
83.
AM M?ller LT Dalgaard F Pociot J Nerup T Hansen O Pedersen 《Canadian Metallurgical Quarterly》1998,41(12):1528-1531
Mutations in the hepatocyte nuclear factor-1alpha (HNF-1alpha) gene are the cause of maturity-onset diabetes of the young type 3 (MODY3), which is characterised by a severe impairment of insulin secretion and an early onset of the disease. Also at onset of diabetes some MODY patients show similar clinical symptoms and signs as patients with Type I (insulin-dependent) diabetes mellitus. The objective of this study was to estimate the prevalence of MODY3 patients misclassified as Type I diabetic patients. From a large population-based sample of unrelated Danish Caucasian Type I diabetic patients with an affected first degree relative, 39 patients (6.7%) who did not carry any high-risk HLA-haplotypes, i.e. DR3 or DR4 or both were examined by single-strand conformational polymorphism scanning and direct sequencing of the coding region and the minimal promoter of the HNF-1alpha gene. Four of the 39 Type I diabetic patients (10%) were identified as carrying mutations in the HNF-1alpha gene. One patient carried a missense mutation (Glu48Lys) in exon 1, two patients carried a missense mutation (Cys241Gly) in exon 4 and one patient carried a frameshift mutation (Pro291fsdelA) in exon 4. The mutations were all identified in heterozygous form, segregated with diabetes, and were not identified in 84 unrelated, healthy subjects. Furthermore, family history in three of the four families showed diabetes in four consecutive generations, suggestive of an autosomal dominant inheritance. In conclusion, about 10% of Danish diabetic patients without a high-risk HLA-haplotype, originally classified as having Type I diabetes could have diabetes caused by mutations in the HNF-1alpha gene. Clinical awareness of family history of diabetes and mode of inheritance might help to identify and reclassify these diabetic subjects as MODY3 patients. 相似文献
84.
. Mass consumerism has brought about increasing consumption of non-renewable natural resources and manufactured goods, and is
creating a waste disposal problem of unprecedented magnitude in the process. In the long run, sustainable manufacturing is
only attainable given environmentally responsible product design. There are many tools for the analysis of the impact of manufactured
products on the environment, but they do not offer a level of detail sufficient to identify environmentally offensive components
in the product. This paper discusses a computer-based design evaluation tool, ECoDE, developed for assessing the environmental
impact of components in a product. ECoDE makes use of the Analytical Hierarchy Process to compare each criterion, and rank
them in an ascending order of relative significance. The types of materials used, their costs, manufacturing processes, reliability,
and ease of access for disassembly are some of the key assessment criteria being considered. Finally, a multi-attribute (or
criteria) rating technique is used to compute the scores against each of the criteria for both components and the overall
product. The larger the score, the less severe the impact of the component or product on the environment. A discussion is
then made on an evaluation test case conducted by ECoDE. Preliminary tests have found that ECoDE is able to calculate the
least environmentally friendly component and highlight its likely causes. 相似文献
85.
N‐Substituted pyrrole derivatives with chiral side groups have been synthesized and electrochemically polymerized in acetonitrile containing tetrabutylammonium perchlorate (TBAClO4) and (S)‐(+)‐camphor‐10‐sulfonic acid ((S)‐(+)‐CSA) or (R)‐(?)‐camphor‐10‐sulfonic acid ((R)‐(?)‐CSA). The resulting N‐substituted polypyrrole films were characterized by cyclic voltammetry, infrared, Raman and X‐ray photoelectron (XPS) spectroscopies. XPS results demonstrated that the as‐grown polymer films are preferably doped by CSA anions when the monomer and the CSA anion have the same optical rotation dispersion (ORD). Furthermore, the conductivities of the polymers synthesized in the media containing CSA with the same ORD of the corresponding monomers were measured to be about 2–10 times higher than those of polymers obtained from electrolytes without CSA. Copyright © 2004 Society of Chemical Industry 相似文献
86.
M Sarr EJ Simoes T Murayi LT Figgs RC Brownson 《Canadian Metallurgical Quarterly》1998,95(12):663-669
BACKGROUND: Breast cancer is a major cause of morbidity and mortality in the United States (U.S.) and Missouri. In 1992, 3,915 new breast cancer cases were diagnosed and in 1995, 1,006 deaths from breast cancer were reported in Missouri. Although breast cancer incidence has increased in Missouri in the past 20 years, there are indications that early detection has also increased during the same period. Knowledge about which segments of the population have experienced the greatest increase in mammography screening rates helps in planning and implementation of breast cancer control programs at the state level. OBJECTIVES: Examine the prevalence and trends of lifetime mammography and 2-year mammography compliance in Missouri by age, race, and education from 1987 to 1995 and make predictions for the years 2000 and 2010. METHODS: We used data from the Missouri Behavioral Risk Factor Surveillance System (BRFSS), 1987 to 1995, to estimate the prevalence of ever having had a mammogram and compliance with mammography screening guidelines within two years by race, age, and education status among Missouri women over age 18. Using linear models, we regressed breast cancer screening prevalence estimates on time to obtain trends and predictions. RESULTS: Overall, African-American women were more likely to have had a lifetime mammogram than white women. However, we found a steady increase in the prevalence of ever having had a mammogram for all groups of women defined by age and education status, except among African Americans. Increase in the prevalence of ever having had a mammogram was much higher in women age 50 and older and slightly higher among women with a high school education or less. The average prevalence of 2-year mammography screening compliance was about 60% for all groups, a rate which did not significantly change between 1987 and 1995. By the year 2000, white women will have mammography rates equal to or higher than African-American women, and the majority of all women age 50 and older (98.3% to 100%) will have had a lifetime mammogram. CONCLUSION: Missouri target populations are predicted to attain Year 2000 National Health Objectives concerning lifetime mammography. Current efforts should be continued in order to maintain levels of mammography, particularly among African-American women. 相似文献
87.
SJ Keeler CL Maloney PY Webber C Patterson LT Hirata SC Falco JA Rice 《Canadian Metallurgical Quarterly》1997,34(1):15-29
Transgenic insect technology will provide opportunities to explore the basic biology of a broad range of insect species in ways that will prove insightful and important. It is also a technology that will provide opportunities to manipulate the genotypes of insects of practical significance to the health and welfare of humans. The Hermes transposable element from the housefly, Musca domestica, is a short inverted repeat-type element related to hobo from Drosophila melanogaster, Ac from Zea mays, and Tam3 from Antirrhinum majus. It has potential to become a versatile and efficient broad host-range insect transformation vector. The ability of Hermes to transpose when introduced into five species of diptera from four divergent families was tested using an in vivo, interplasmid transpositional recombination assay. Hermes was capable of transposing in all species tested, demonstrating that Hermes has a broad host-range. In addition, the rates of transposition were sufficiently high in all species tested to suggest that Hermes will be an efficient gene transfer vector in a wide range of insect species. The Hermes element also revealed a pattern of integration into the target substrate that permitted factors determining integration site selection to be identified. Primary nucleotide sequence of the integration site played a role as did proximity to preferred integration sites and the nucleosomal organization of the target. 相似文献
88.
KS Yarnall BK Rimer D Hynes G Watson PR Lyna CT Woods-Powell J Terrenoire LT Barber 《Canadian Metallurgical Quarterly》1998,11(2):96-104
One hundred eleven (58%) of 191 adolescent inpatients previously admitted to the emergency wards at the Child and Adolescent Psychiatric Clinics in the cities of Uppsala and G?teborg participated in a 2-4 year follow-up evaluation. The prevalence, incidence, and stability of depressive symptoms, suicidal ideation, and suicide attempts among the adolescents, and predictors of follow-up functioning were examined. Although a majority of the patients substantially reduced their depressive symptoms over the 2-4 year period, a smaller group (13%), mainly girls (94%), continued reporting high symptom levels at follow-up, and one out of five adolescents had moderate-severe levels of suicidal ideation. The accumulated frequency of suicide attempts among the patients shortly prior to hospitalization and during the follow-up was 59% including two patients who committed suicide. Significant predictors of depressive symptom severity at follow-up were depressive symptom scores and V-diagnoses at inpatient assessment. Previous suicide attempts before hospitalization, high levels of self-reported depressive symptoms and nonintact family status at inpatient assessment predicted suicide attempts during the follow-up period. The high prevalence of attempted and completed suicide in this clinical group underscores the importance of developing effective treatments for suicidal adolescents. 相似文献
89.
90.
GJ Despotis JH Joist CW Hogue A Alsoufiev D Joiner-Maier SA Santoro E Spitznagel JI Weitz LT Goodnough 《Canadian Metallurgical Quarterly》1996,76(6):902-908
This study was designed to determine whether the maintenance of higher than usual patient-specific heparin concentrations during cardiopulmonary bypass (CPB) was associated with more effective suppression of hemostasis system activation. Thirty-one patients scheduled for repeat cardiac surgery or combined procedures (i.e., coronary revascularization + valve repair/replacement) were consented and enrolled in this study. All patients received porcine heparin and protamine and were randomly assigned to monitoring of anticoagulation by either celite ACT alone (Control, n = 16) or by kaolin ACT combined with on-site measurements of whole blood heparin concentration (Intervention, n = 15). Blood specimens collected before administration of heparin, before weaning from CPB and after administration of protamine were analyzed with a battery of coagulation assays. Patients in the intervention cohort received appreciably greater heparin doses than control patients, resulting in higher anti-Xa heparin levels at the end of CPB. Fibrinopeptide A and D-dimer levels were higher in the control group before discontinuation of CPB. Percent decrease during CPB were greater in the control group for factors V and VIII, fibrinogen and antithrombin III. Percent decrease in complement 3 was greater in the control group after protamine and bleeding times measured in the Intensive Care Unit were significantly more prolonged in this group. Maintenance of higher patient-specific heparin concentrations during CPB more effectively suppresses excessive hemostatic system activation than do standard heparin doses chosen based on measurement of ACT. These findings may explain, at least in part, the significant reduction in perioperative blood loss and blood product use when higher heparin concentrations are maintained. 相似文献