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41.
42.
Understanding the retention time of water in waterbodies during periods of no surface flow in dryland rivers provides an important context for evaluating the ecological importance of a waterhole to the river system. Time series of water level data were collected from 10 waterbodies spread across three river systems of the Lake Eyre Basin (LBE), Australia. Observed loss rates in the absence of surface flow were compared to modelled evaporation rates in order to determine whether open water evaporation was the main loss process from isolated waterholes and to what extent there is evidence of interaction between the surface water and any shallow groundwater aquifers. The modelled evaporation rates were determined using the Penman combination equation and meteorological data from the closest climate station in the region of the waterbodies. The modelled evaporation data were able to explain only some of the variability in the observed loss data but did highlight periods where other processes (including observation error) need to be invoked. These other possible processes, which include temporary groundwater connection and the effect of heat storage on the evaporation losses, probably contribute as much to the observed data variability as error introduced by the use of regional meteorological data. Assuming evaporation is the dominant process determining water loss in the absence of flow, the persistence of a waterhole is primarily dependent upon its depth when flow ceases. The annual loss shown by most waterbodies lies within the range of the modelled evaporation rate using the Penman combination equation and equates between 1.5 and 2.5 m per annum. The use of water level data in conjunction with the modelled evaporation rates was able to provide important insights into controls on waterbody loss rates and persistence. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
43.
Elyse R Park Susan Kleimann Julie A Pelan Alexandra E Shields 《Nicotine & tobacco research》2007,9(2):271-279
Emerging research will likely make it possible to tailor pharmacological treatment for individuals with tobacco dependence by genotype. This study explored primary care physicians' attitudes about the strengths of and barriers to using genetic testing to match patients to optimal nicotine replacement therapy. Four focus groups (n=27) were conducted, and data were analyzed using thematic content analysis. Physicians reported how likely they would be to offer patients a genetic test to tailor smoking treatment in response to three different scenarios that described characteristics of the genetic test based on published research. Respondents were on average 36 years of age; 59% were male and 67% were white. Physicians believed genetically tailored treatment may offer new hope to smokers trying to quit, yet they also noted several potential barriers to clinical integration. Barriers included erroneous assumptions by patients regarding the meaning of genetic test results, possible misinterpretation of information regarding racial differences in the prevalence of certain risk alleles, and potential discrimination against patients undergoing testing. Concerns increased dramatically when physicians were told that the same genotypes that would be identified to tailor smoking treatment also have been associated with increased risk of becoming addicted to nicotine, as well as other addictions and psychiatric disorders. Physicians were interested in the possibility of realizing improved smoking cessation outcomes through pharmacogenetic developments, but they also raised many concerns. Primary care physicians will need additional educational inputs and system support prior to integrating genetic testing for a common trait into their routine clinical practice. 相似文献
44.
We report severe aplastic anemia of neonatal onset diagnosed in six girls between 1985 and 1995 in a single center. Initial blood cell counts (mean age 3.8 days old, 1 to 15 days) showed thrombocytopenia (six of six), anemia (four of six), and neutropenia (two of six). Neutrophil counts gradually decreased below 0.5 x 10(9)/L, and severe aplastic anemia occurred in three patients by 3 months of age and in all patients by 1 year of age. Lymphocyte number and functions were normal. In all children bone marrow biopsy showed hypocellularity for age and absence of fibrosis, blasts, lymphocytic infiltrates, and cytologic abnormalities. Blood and medullary cytogenetic studies were normal. A search for known constitutional, viral, or toxic causes was negative. Immunosuppressive therapy failed to restore hematopoiesis (three of six). Five children received a bone marrow transplantation at an average age of 9 months (range 2.7 to 29 months). One child is alive and well after a human leukocyte antigen-identical bone marrow transplantation, whereas the other four died. Both congenital onset and the high rate of familial involvement suggest that this condition may be inherited. 相似文献
45.
46.
To foster the study of emotion regulation beyond infancy and toddlerhood, a new criterion Q-sort was constructed. In Study 1, Q-scales for emotion regulation and autonomy were developed, and analyses supported their discriminant validity. Study 2 further explored the construct validity of the Emotion Regulation Q-Scale within a sample of 143 maltreated and 80 impoverished children, aged 6 to 12 years. A multitrait-multimethod matrix and confirmatory factor analyses indicated impressive convergence among the Emotion Regulation Q-Scale and established measures of affect regulation. This new scale also was discriminable from measures of related constructs, including Q-sort assessments of ego resiliency. The use of this new measure was further supported by its ability to distinguish between maltreated and comparison children and between groups of well-regulated versus dysregulated children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
This paper describes frequency dependence measurements of fused-silica capacitance standards from 200 to 2000 Hz, using a 1-pF cross-capacitor as the reference. The measured frequency dependence of fused-silica capacitors was found to vary significantly, ranging from a change of less than 0.2 /spl mu/F/F for one standard to a change of 0.8 /spl mu/F/F for another over the frequency range. Increasing capacitances with decreasing frequency from 1592 Hz for all tested fused-silica capacitors indicates that dielectric relaxation due to dielectric bulk and/or interfacial defects is the dominant source of frequency dependence. The relative combined standard uncertainty at 200 Hz (the largest in the frequency range) is 0.07 /spl mu/F/F, which is smaller by about a factor of three than the uncertainty reported previously from the National Institute of Standards and Technology (NIST). 相似文献
48.
SH Shaw M Kelly AB Smith G Shields PJ Hopkins J Loftus SH Laval A Vita M De Hert LR Cardon TJ Crow R Sherrington LE DeLisi 《Canadian Metallurgical Quarterly》1998,81(5):364-376
We completed a systematic genome-wide search for evidence of loci linked to schizophrenia using a collection of 70 pedigrees containing multiple affected individuals according to three phenotype classifications: schizophrenia only (48 pedigrees; 70 sib-pairs); schizophrenia plus schizoaffective disorder (70 pedigrees; 101 sib-pairs); and a broad category consisting of schizophrenia, schizoaffective disorder, paranoid or schizotypal personality disorder, psychosis not otherwise specified (NOS), delusional disorder, and brief reactive psychosis (70 pedigrees; 111 sib-pairs). All 70 families contained at least one individual affected with chronic schizophrenia according to DSM-III-R criteria. Three hundred and thirty-eight markers spanning the genome were typed in all pedigrees for an average resolution of 10.5 cM (range, 0-31 cM) and an average heterozygosity of 74.3% per marker. The data were analyzed using multipoint nonparametric allele-sharing and traditional two-point lod score analyses using dominant and recessive, affecteds-only models. Twelve chromosomes (1, 2, 4, 5, 8, 10, 11, 12, 13, 14, 16, and 22) had at least one region with a nominal P value <0.05, and two of these chromosomes had a nominal P value <0.01 (chromosomes 13 and 16), using allele-sharing tests in GENEHUNTER. Five chromosomes (1, 2, 4, 11, and 13) had at least one marker with a lod score >2.0, allowing for heterogeneity. These regions will be saturated with additional markers and investigated in a new, larger set of families to test for replication. 相似文献
49.
In this study we examined the effect of a nurse-managed cholesterol screening program on the preventive health behaviours (e.g., diet changes, weight loss, medical surveillance) of 534 Hutterites. Hutterites are the largest single rural ethnic group in Canada and they have been found to be at high risk for heart disease. Eighty-one percent of the participants engaged in at least one preventive behaviour. Ongoing cholesterol surveillance was reported by 34.5% of the participants. Weight loss and dietary fat reduction were reported by 31% and 62% of the respondents, respectively. Seven percent of the respondents began lipid-lowering pharmacologic therapy. Screening cholesterol levels and age were significantly related to all of the outcomes except weight loss. This study provides evidence that community-based screening accompanied by counselling and referral by nurses can positively affect preventive behaviours. 相似文献
50.
A 68-year-old man with lung carcinoma and no systemic metastasis presented with a blind, painful right eye. Examination showed no perception of light in the affected eye, elevated intraocular pressure, marked epibulbar hyperemia, and a white placoid mass in the conjunctiva nasally. Although a cataract precluded a clear view of the fundus, ultrasonography disclosed a total retinal detachment and a diffuse thickening of the choroid. Metastatic carcinoma was suspected clinically and the eye was enucleated because of severe, intractable pain. Pathologic examination demonstrated extensively necrotic metastatic adenocarcinoma involving the conjunctiva, peripheral cornea, sclera, iris, ciliary body, choroid, optic nerve, subarachnoid space, and orbit. Metastatic disease usually affects a singular ocular tissue, and it is highly unusual for such widespread ocular involvement to be the first sign of systemic metastasis from a primary neoplasm. 相似文献