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951.
We describe a 31-year-old man who developed sudden painful loss of vision in the right eye and was found to have a retrobulbar optic neuropathy. Magnetic resonance (MR) imaging gave normal results, and a diagnosis of retrobulbar optic neuritis was made. The patient was treated with oral prednisone, but he continued to lose vision in the right eye and then began to lose vision in the left eye. Repeat MR imaging performed eight weeks after the initial study showed a giant intracranial aneurysm compressing the right and left optic nerves. Cerebral angiography revealed that the aneurysm arose from the origin of the right ophthalmic artery. Treatment of the aneurysm by a trapping procedure resulted in improvement in vision in the left eye but no change in vision in the right eye. This report emphasizes the difficulty in imaging intracranial aneurysms of various sizes, the rapidity with which intracranial aneurysms can enlarge, and the importance of continued follow-up examinations in patients thought to have idiopathic optic neuritis. 相似文献
952.
Based on the Tesla‐type turbomachinery principle of operation, a fan consisting of flat, round discs arranged in between two separate channels, which generate two air flows in opposite directions, is investigated. Simulations of a model with one disc as well as a five‐channel model at different grids were performed. With almost unthrottled operation, secondary flows could be determined at velocity magnitudes of up to 20 % of the mean main flow velocity, with secondary currents reaching up to 50 % in throttled operation. Besides high dissipation and recirculation, these secondary currencies are found to be capable of reducing the overall efficiency of the system. Thus, topic of further investigations is the potential of increasing efficiency by means of straighteners and geometric adaptions. 相似文献
953.
A long term epidemiological study of bovine viral diarrhoea infections in a large herd of dairy cattle 总被引:2,自引:0,他引:2
A Moerman PJ Straver MC de Jong J Quak T Baanvinger JT van Oirschot 《Canadian Metallurgical Quarterly》1993,132(25):622-626
Epidemiological aspects of bovine viral diarrhoea virus (BVDV) infections were studied longitudinally in a large dairy herd for three years. At the start of the study, practically all the cows more than four years old had BVDV antibody titres, whereas the younger stock were almost all seronegative. The spread of the virus was monitored in a part of the population that contained only transiently viraemic cattle and in another part that contained persistently viraemic calves. Among the lactating cows the virus circulated for two-and-a-half years, although they had no direct contact with persistently viraemic cattle during this period. The highest transmission rate occurred when a large number of susceptible heifers was added to the population of cows that contained transiently viraemic cattle. The circulation of BVDV among the lactating cows ceased while 27 seronegative cows were still present. Both findings are in accordance with predictions from simple epidemic models. The susceptibility of the cows that remained seronegative was confirmed experimentally. In contrast with the limited circulation of BVDV caused by transiently viraemic cattle, virtually all susceptible cattle that came into contact with a persistently viraemic calf became seropositive within three months. Transplacental BVDV infections were not detected in the calves born to cows that had antibodies against the virus due to an infection that had occurred at least four years earlier. Transplacental transmission of BVDV did not occur in most of the pregnant cows that were infected before approximately the 60th day of gestation, but when cows became infected later in gestation the virus virtually always invaded the fetus.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
954.
JA Chapman PJ DiSaia K Osann PD Roth DL Gillotte ML Berman 《Canadian Metallurgical Quarterly》1996,175(5):1195-1200
OBJECTIVE: Our purpose was to evaluate our experience with estrogen replacement in women with a history of early-stage endometrial cancer and to determine whether it increased the risk for recurrence or death. STUDY DESIGN: A retrospective review was performed of 123 women with surgical stage I and II endometrial adenocarcinoma treated between 1984 and 1994; 62 had received estrogen replacement therapy after cancer therapy. Sixty-one women received no estrogen. Variables analyzed included age parity, surgical stage, grade, depth of myometrial invasion, presence of intercurrent illnesses, duration of follow-up, and duration of estrogen replacement, if applicable. Outcome variables assessed included recurrence rate, time to recurrence, and disease-free interval. RESULTS: The estrogen replacement therapy group had earlier stage disease (p = 0.04) and less severe depth of invasion (p = 0.003); however, the total number of deaths in each group was not significantly different. The disease-free survival in the estrogen replacement therapy group did not differ significantly compared with those not receiving estrogen replacement therapy. The data are suggestive of improved disease-free survival in the estrogen replacement therapy group, which may be related to differences in age, stage, grade, and depth of invasion. The overall recurrence rate was 6.5%, with an overall death rate of 1.6%. CONCLUSIONS: There is no evidence to suggest that estrogen decreased the disease-free interval or increased the risk for recurrence in early-stage disease. 相似文献
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956.
IP Costa NH Yoshinari PJ Barros VL Bonoldi EP Leon AD Zeitune W Cossermelli 《Canadian Metallurgical Quarterly》1996,51(6):253-257
The authors report the occurrence of the first three clinical cases of Lyme disease in Mato Grosso do Sul State, including the first case of Lyme meningitis in Brazil. These were identified by clinical and laboratorial criteria. Anti-Borrelia burgdorferi antibody search was carried out through ELISA and Western Blotting techniques, the former providing identification of IgG class antibodies alone, in one only of those cases. Through Immunoblotting, the following features were found in serum: 5 IgG and 2 IgM bands for the first case; 7 IgG and 2 IgM bands for the second; and 5 IgG and 6 IgM bands for the third. In the latter, presence fo specific antibodies was searched in liquor, due to lymphomonocitary meningitis occurrence, and one IgM band was detected. After antibiotic therapy, all patients exhibited significant clinical and laboratorial improvement in their conditions along with symptom regression to the present moment. 相似文献
957.
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960.
E Koss MB Patterson R Ownby JC Stuckey PJ Whitehouse 《Canadian Metallurgical Quarterly》1993,50(1):92-97
OBJECTIVES: To evaluate if caregivers are reliable informants concerning memory deficits in patients with Alzheimer's disease (AD). DESIGN: Responses of caregivers of patients with probable AD and responses of healthy control subjects on a standardized memory questionnaire were compared with objective measures of cognition (Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery) and with clinical estimates of activities of daily living, depression, and psychopathology (Consortium to Establish a Registry for Alzheimer's Disease [CERAD] clinical assessment battery) using the Self-report Memory Questionnaire. SETTING: A federally funded AD research center. SUBJECTS: The referred sample included 117 patients with probable AD, their informants, and 41 healthy control subjects age-matched to the patients. Patients and control subjects were between the ages of 58 and 85 years, had between 9 and 19 years of education, and were in good health. EXCLUSIONS: Patients who did not meet NINCDS-ADRDA criteria of probable AD. MAIN OUTCOME MEASURE: The optimal number of questionnaire items yielding the best combination of sensitivity and specificity. RESULTS: An abbreviated version of the scale, renamed the Short-Memory Questionnaire, had excellent specificity and sensitivity for identifying dementia. Positive and negative predictive values were 63.5% and near 100%, respectively. The Short-Memory Questionnaire showed good reliability, internal consistency, and external validity. Caregiver appraisals of memory deficits significantly correlated with objective measures of memory and also with generalized cognitive dysfunction. CONCLUSIONS: Caregivers of patients with AD are reliable informants of their relatives' deficits. The Short-Memory Questionnaire is an easily administered, informant-based scale that may be useful in clinical settings or epidemiologic studies to screen out persons with memory difficulties. 相似文献