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131.
Lilian Grau Damien Blaudez Dimitri Heintz Julie Zumsteg David Billet Aurlie Cbron 《International journal of molecular sciences》2022,23(11)
Microbial populations associated to poplar are well described in non-contaminated and metal-contaminated environments but more poorly in the context of polycyclic aromatic hydrocarbon (PAH) contamination. This study aimed to understand how a gradient of phenanthrene (PHE) contamination affects poplar growth and the fungal microbiome in both soil and plant endosphere (roots, stems and leaves). Plant growth and fitness parameters indicated that the growth of Populus canadensis was impaired when PHE concentration increased above 400 mg kg−1. Values of alpha-diversity indicators of fungal diversity and richness were not affected by the PHE gradient. The PHE contamination had a stronger impact on the fungal community composition in the soil and root compartments compared to that of the aboveground organs. Most of the indicator species whose relative abundance was correlated with PHE contamination decreased along the gradient indicating a toxic effect of PHE on these fungal OTUs (Operational Taxonomic Units). However, the relative abundance of some OTUs such as Cadophora, Alternaria and Aspergillus, potentially linked to PHE degradation or being plant-beneficial taxa, increased along the gradient. Finally, this study allowed a deeper understanding of the dual response of plant and fungal communities in the case of a soil PAH contamination gradient leading to new perspectives on fungal assisted phytoremediation. 相似文献
132.
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
133.
A group of 30 consecutive patients with iatrogenic vascular injury were studied to determine the aetiology of the condition and to investigate its possible prevention. Of the patients, 18 were males and 12 females; mean age was 37.0 years (range 2 weeks to 70 years). Most injuries (n = 25) involved the arterial system; eight cases (27%) were recognized during the operative procedure. The most common presentations were bleeding and chronic ischaemia. Cannulation of vessels was the cause of injury in 14 cases (47%); two-thirds of these were iatrogenic in nature. A conservative policy was adopted in nine patients; surgery was planned but not performed in two. A total of 19 patients were operated on (17 reconstructions, one ligation, one fasciotomy); two died from causes related to their original condition. In order to reduce the incidence of iatrogenic injury, medical personnel should be informed of possible vessel damage, especially during cannulation. All surgical and radiological procedures should be carefully audited. 相似文献
134.
135.
NH Ogden K Bown BK Horrocks Z Woldehiwet M Bennett 《Canadian Metallurgical Quarterly》1998,12(4):423-429
BACKGROUND: The number of patients waiting lung transplantation greatly exceeds the supply of donors. This study was conducted to determine the effect of high-dose steroid administration on oxygenation and donor lung recovery after brain death. METHODS: A retrospective analysis was conducted on 118 consecutive organ donors from January 1 through December 31, 1995. Eighty donors received high-dose steroids (methylprednisolone, mean 14.5+/-0.06 mg/kg) after organ procurement organization management began; a second group was composed of 38 patients who received no steroids. PaO2/FiO2 ratios were used to evaluate oxygenation. The number of single and double lungs transplanted served as the endpoint. RESULTS: No differences were noted in hemodynamics, most clinical or demographic variables and initial values of PaO2/FiO2 between groups. However, nonsteroid-treated donors showed an overall decrease in oxygenation (mean decrease in PaO2/FiO2 -34.2+/-14), whereas steroid-treated donors had a significant and progressive increase in oxygenation (mean increase in PaO2/FiO2: 16+/-14) before aortic cross-clamping (p = 0.01). Time before cross-clamping was longer in the steroid-treated patients (p = 0.003). The number of procured lungs was markedly greater in steroid-treated than nonsteroid-treated donors (25/80 patients vs 3/38; p < 0.01). CONCLUSIONS: High-dose methylprednisolone given during donor management results in improved oxygenation at organ recovery. This treatment resulted in a significant increase in the number of lungs transplanted and may have enabled donors to be treated longer. 相似文献
136.
Therapy-related acute myeloid leukemias with balanced translocations affecting the 11q23 chromosome region are one of the most serious complications of treatments with topoisomerase II inhibitor drugs as epipodophillotoxins and anthracyclines. 1,2-5 These cases are usually associated with short interval time from previous chemotherapies, absence of myeloid dysplastic phase, hyperleukocytosis and young age. We and others have recently identified and cloned the ALL1 gene at 11q23 band (also named MLL, HRX. Hrxt) which is consistently altered in t-AML following therapies with topo II targeting drugs. However, there are few reports of cases of t-AML, clinically and biologically similar to the subtype of leukemias secondary to exposure to topo II inhibitors drugs but without the involvement of the ALL1 gene. These observations suggest that genes other than ALL1 which are etiopathogenetically relevant for hematological neoplasias are located in this cytogenetic region. 相似文献
137.
NH Bjarnason J Haarbo I Byrjalsen RF Kauffman C Christiansen 《Canadian Metallurgical Quarterly》1997,96(6):1964-1969
BACKGROUND: The beneficial effect of long-term hormone replacement therapy in terms of a decreased risk of cardiovascular disease is now generally accepted. Raloxifene, a selective estrogen receptor modulator, has demonstrated hypolipidemic properties while leaving the endometrium unstimulated. METHODS AND RESULTS: For our study of the effects of raloxifene on atherosclerosis, 75 rabbits were ovariectomized and treated with either raloxifene, 17beta-estradiol, or placebo; 25 rabbits were sham operated and treated with placebo. After 45 weeks, the raloxifene group had two thirds of the aortic atherosclerosis, as evaluated by the cholesterol content of the proximal inner part of the aorta, found in the placebo group (placebo, 577+/-55.1 nmol/mg protein; raloxifene, 397+/-53.6 nmol/mg protein; P<.05); the estrogen group had one third of the aortic atherosclerosis in the placebo group (estrogen, 177+/-32.1 nmol/mg protein; P<.001). The sham-operated group (473+/-59.6 nmol/mg protein) was not significantly different from placebo. These effects were only partly explained by the changes in serum lipids and lipoproteins, and treatment with both estrogen and raloxifene independently predicted the response in aorta cholesterol. Because plasma levels of total raloxifene were low relative to clinical values in postmenopausal women, dose-response data for raloxifene are required. CONCLUSIONS: Our findings indicate that raloxifene hydrochloride has a potentially important antiatherogenic effect, analogous to that observed with estrogen in this model. 相似文献
138.
Scientific dishonesty has been the subject of much public interest in recent years. Although the problem has had a low profile in Denmark, there is no reason to believe that it is non-existent. Several preconditions known to be important prevail here as well as in other countries, such as pressure to publish and severe competition for research grants and senior academic positions. The Danish Medical Research Council (DMRC) decided to respond to this problem by preparing a report on scientific dishonesty with suggestions to the research institutions on rules for good scientific practice and procedures for investigation of suspected dishonesty. To this end, an investigatory system was suggested. The system should consist of two regional committees and one national committee. They should be headed by high court judges and experienced health sciences researchers as members. The committees will investigate cases reported to them and conclude on whether dishonesty has been established and on whether the scientific work should be retracted. Sanctions shall remain the task of the institutions. Preventive measures comprise open access to and a long storage period for scientific data. 相似文献
139.
HF el-Sayed NH Rizkalla S Mehanna SM Abaza PJ Winch 《Canadian Metallurgical Quarterly》1995,52(2):194-198
Projects are being carried out in many regions of Egypt to reclaim land from the desert for agriculture. This paper presents findings from a baseline epidemiologic study conducted in 1992 in two newly reclaimed areas near Ismailia, Egypt. In the first area, just east of the Suez Canal, 40.0% of the residents tested positive for Schistosoma mansoni and 1.7% tested positive for S. haematobium, while in the second area, 15 km southwest of Ismailia, 49.3% tested positive for S. mansoni and 3.3% tested positive for S. haematobium. The intensities of S. mansoni infection were moderately high, with a geometric mean egg count of 76 eggs/gram of feces among positive individuals in the first area, and 100 eggs/gram of feces in the second area. When compared with a previous study conducted in 1985, the prevalence of S. mansoni infection in the first area has increased from 21.7% to 42.1% among settlers in the last seven years, while that of S. haematobium has decreased from 7.8% to 1.7%. These trends may result from changes in irrigation practices or other alterations in the local environment. There is a risk of schistosomiasis becoming a major public health problem in reclaimed areas if adequate control measures are not taken. 相似文献
140.
OBJECTIVE: To review reported cases of hyponatremia and the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with the use of selective serotonin reuptake inhibitors (SSRIs). DATA SOURCES: A search of MEDLINE for reports of hyponatremia and SIADH associated with the use of fluoxetine, fluvoxamine, paroxetine or sertraline published between January 1980 and May 1995. Unpublished reports of cases were requested from the pharmaceutical industry, the Ontario Medical Association, the Health Protection Branch of Health Canada, the US Food and Drug Administration and the World Health Organization. DATA SELECTION AND EXTRACTION: Spontaneous reports from postmarketing surveillance. DATA SYNTHESIS: A total of 736 cases of hyponatremia [corrected] and SIADH associated with SSRI use were reported. Fluoxetine was involved in 554 (75.3%) of the cases, paroxetine in 91 (12.4%), sertraline in 86 (11.7%) and fluvoxamine in 11 (1.5%). Reports of 30 cases were published. The remaining 706 cases were reported to monitoring bodies and the pharmaceutical industry. According to information in the published reports, the median time to onset of hyponatremia was 13 days (range 3 to 120 days). Most (83%) of the published cases involved patients 65 years of age or more, as compared with 74% of the unpublished cases. CONCLUSION: Elderly people may be at increased risk for hyponatremia associated with SSRI use. Physicians caring for elderly patients should be aware of this potentially serious but reversible adverse effect. Further research is required to determine the incidence of this adverse effect, the relative risk of hyponatremia and SIADH in different age groups and the risk associated with different SSRI drugs. 相似文献