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951.
S Salami G Tellides TM Ramahi L Rosenfeld WP Batsford PS Milstein JA Elefteriades 《Canadian Metallurgical Quarterly》1997,61(3):131-134
On the basis of long clinical experience principles are substantiated and schemes are suggested of therapy of childhood disseminated sclerosis (DS), these being as follows: 1) pulse therapy with high dose intravenous corticosteroids, a switch-over to oral intake followed by synacten-depo during the phase of exacerbation; 2) long-term maintenance therapy during transition to the phase of remission. The above algorithm allowed the patients to be helped out of the exacerbation. Analysis of 3-to-11 yr catamnesis permitted assessing the efficacy and outcomes of the proposed therapy in children. Of the 21 cases, thirteen showed stabilization of the process as evidenced by continuing remission of one to 3 years in duration. Eight children showed short-time remission, with neurological deficit slowly progressing, resulting in invalidism in 7 patients. In summary, the proposed therapeutic regimen for DS exacerbation in children permits achieving quick regression of the neurologic symptomatology, returning progression of neurological deficit, which observation was recordable in two thirds of the patients. In 1/2 of children DS runs an aggressive course that does not respond even to intensive therapy; in these, long-term remission was not achievable, this resulting in progression of the neurologic symptomatology and, in the long run, disability under protracted course of the condition. 相似文献
952.
BACKGROUND: Allergen immunotherapy results in a number of changes in clinical, inflammatory, and immunologic parameters. However, the basis for the specificity of this form of therapy is unknown, especially in the context of changes in T- and B-lymphocyte function after desensitization to specific allergens. OBJECTIVE: This study was designed to determine the immunologic consequences of rush immunotherapy. METHODS: We studied 10 patients who had positive skin test responses to the house dust mite Dermatophagoides pteronyssinus (Dpt) and cat dander extract. Each received rush immunotherapy to mite, but not cat dander, over a 2- to 4-week period until maintenance was achieved. Patients were evaluated before and when maintenance was achieved for skin test and nasal reactivity to mite and cat dander; antibody levels to the allergen were monitored, as were lymphocyte proliferative responses and cytokine production. RESULTS: Rush immunotherapy to house dust mite resulted in a significant reduction in skin and nasal reactivity to mite allergen, but not to cat allergen, in 10 of 10 patients. This was accompanied by a rise in serum anti-Dpt IgE, whereas anti-cat IgE was not altered (7 of 7 patients). In seven of seven patients there was an increase in anti-Dpt IgG4 levels. T-cell proliferative responses to mite antigen were suppressed, and numbers of CD8+ T cells increased in frequency. There was a marked increase in interferon-gamma production, particularly by CD4+ T cells in 10 of 10 patients. The correlation between the increases in interferon-gamma production and the changes in cutaneous reactivity was highly significant. CONCLUSION: We show that rush immunotherapy is immunologically specific in eliciting changes in T- and B-cell responses to the desensitization antigen. The specificity and potential benefit of immunotherapy may be linked to the increase in interferon-gamma production by allergen-activated CD4+ T lymphocytes. 相似文献
953.
TC Pearson DZ Alexander M Corbascio R Hendrix SC Ritchie PS Linsley D Faherty CP Larsen 《Canadian Metallurgical Quarterly》1997,63(10):1463-1469
Stimulus control induced by (-)-2,5-dimethoxy-4-methylamphetamine (DOM) is believed to be mediated by agonism at 5-HT2A receptors. We hypothesized that blockade of (-) DOM-induced stimulus control may thus prove useful in the pre-clinical characterization of novel antipsychotic agents by providing an in vivo index of antagonism at that receptor. A previous study (Fiorella et al., 1995a) observed no antagonism by typical agents such as haloperidol and thioridazine, partial antagonism by the atypical agent, clozapine, and full antagonism by risperidone, a second atypical antipsychotic. The present investigation extends these observations to include seven additional drugs: SCH 23390, sulpiride, amperozide, melperone, octoclothepin, tiospirone and ritanserin. Of the drugs tested in rats in which (-) DOM-induced stimulus control had reliably been established, only tiospirone and ritanserin produced complete antagonism of the (-) DOM stimulus. Intermediate levels of antagonism were observed following treatment with amperozide, melperone, and octoclothepin. Finally, SCH 23390 and sulpiride yielded no evidence of antagonistic activity in (-) DOM-trained animals. Because clozapine and risperidone are both classified as atypical antipsychotics yet yield different degrees of antagonism of (-) DOM-induced stimulus control, we tested the substitution of risperidone for clozapine in rats trained with clozapine as a discriminative stimulus. No significant substitution was observed. In conclusion it appears that complete or partial antagonism of the (-) DOM stimulus serves as an effective pre-clinical means of identifying antipsychotics with significant 5-HT2A antagonist properties. However, the failure of risperidone to substitute for clozapine in pigeons (Hoenicke et al., 1992) and in rats (present study) suggests that despite their shared 5-HT2A antagonist properties, clozapine and risperidone differ with respect to their stimulus effects. 相似文献
954.
955.
Complementary nursing was developed in response to the need for maintaining high quality care while controlling health care costs. The complementary nurse provides comprehensive management of complex patients through an entire episode of an acute illness, to transition them back to a prehospital state through interdisciplinary discharge planning. In this article, the authors describe the process used in developing and implementing this new integrated role of acute care case management. The article contains role responsibilities, communication tools, and lessons learned from experience. 相似文献
956.
The search for intracellular phosphoproteins implicated in the regulation of neuronal differentiation led to the identification of Ulip1, a mammalian protein related to the Caenorhabditis elegans unc-33 gene product [Byk, T., Dobransky, T., Cifuentes-Diaz, C. & Sobel, A. (1996) J. Neurosc. 16, 688-701]. The expression level and phosphorylation pattern of Ulip1 were shown to be strongly regulated during development and neuronal differentiation. We have isolated three additional complete coding sequences for members of the Ulip family in the mouse, Ulips 2-4, all preferentially expressed in the nervous system. Furthermore, two Ulip sequences, Ulips A and Ulips B, could be identified in C. elegans. The Ulip family is highly conserved throughout evolution (more than 96 % for Ulips 1-3 and 92.5 % for Ulip4 between mouse and human) and the various members of the family within a single species display about 75% similarity. Sequence comparisons further reveal several highly similar domains and subdomains, including a 32-amino-acid region highly conserved from a bacterial hydantoinase to human Ulips. Two-dimensional immunoblot analysis of in vitro translated Ulips 1-4 demonstrates the existence, for each Ulip protein, of several, most probably differentially phosphorylated forms, in agreement with the presence of conserved phosphorylation consensus sites within their sequences. The expression of Ulips 1-4 mRNAs is differentially regulated during development and nerve-growth-factor-induced neuronal differentiation of PC12 cells. Our results indicate a differential, possibly complementary role of phosphoproteins of the highly conserved Ulip family in the control of neuronal differentiation, in relation with the development and plasticity of the nervous system. 相似文献
957.
TR Licht KA Krogfelt PS Cohen LK Poulsen J Urbance S Molin 《Canadian Metallurgical Quarterly》1996,64(9):3811-3817
An avirulent, streptomycin-resistant Salmonella typhimurium strain, SL5319, and its lipopolysaccharide (LPS)-deficient mutant strain, SL5325, differ in their ability to colonize the large intestines of streptomycin-treated mice. When fed to mice independently, the strains colonize equally well, but when fed together, the LPS-deficient mutant is outcompeted by the wild-type strain during establishment in the gut (J.J. Nevola, B.A.D. Stocker, D.C. Laux, and P.S. Cohen, Infect. Immun. 50:152-159, 1985). In the present study, the spatial distribution in the intestinal mucosal layer of the two strains was visualized by specific hybridization to bacterial rRNA in histological sections of mouse colon and cecum. The first day after infection, 9.8% of the smooth SL5319 cells observed in mucus were found to be associated with the mouse epithelial cells, but three days after infection, the corresponding fraction of adhering bacteria was reduced to 2.1%. The LPS-deficient S. typhimurium strain was confined to the part of the mucosal layer closest to the colonic lumen and was not observed to adhere to the epithelium either at day 1 or 3 after infection. Quantitative determinations of the distance from the S. typhimurium cells to the epithelial wall confirmed that the average distance for the rough S. typhimurium SL5325 was much larger than for its smooth counterpart, S. typhimurium SL5319. Quantification of the hybridization signal from bacteria isolated from the cecal mucus revealed that the two strains had the same ribosome concentration, indicating that they have the same potential for growth in the intestinal environment. On the basis of these observations, we suggest that the better colonization ability of the strain carrying wild-type LPS is due to the better abilities to penetrate the intestinal mucosal layer and to subsequently bind to the epithelial cells in vivo. 相似文献
958.
PS Bernstein MD Yoshida NB Katz RW McClane W Gellermann 《Canadian Metallurgical Quarterly》1998,39(11):2003-2011
We are developing procedures to repeatedly and noninvasively image the expression of transplanted reporter genes in living animals and in patients, using PET. We have investigated the use of the Herpes Simplex Virus type 1 thymidine kinase gene (HSV1-tk) as a reporter gene and [8-14C]-ganciclovir as a reporter probe. HSV1-tk, when expressed, leads to phosphorylation of [8-14C]-ganciclovir. As a result, specific accumulation of phosphorylated [8-14C]-ganciclovir should occur almost exclusively in tissues expressing the HSV1-tk gene. METHODS: An adenoviral vector was constructed carrying the HSV1-tk gene along with a control vector. C6 rat glioma cells were infected with either viral vector and uptake of [8-3H]-ganciclovir was determined. In addition, 12 mice were injected with varying levels of either viral vector. Adenovirus administration in mice leads primarily to liver infection. Forty-eight hours later the mice were injected with [8-14C]-ganciclovir, and 1 hr later the mice were sacrificed and biodistribution studies performed. Digital whole-body autoradiography also was performed on separate animals. HSV1-tk expression was assayed, using both normalized HSV1-tk mRNA levels and relative HSV1-TK enzyme levels, in both the cell culture and murine studies. RESULTS: Cell culture, murine tissue biodistribution and murine in vivo digital whole-body autoradiography all demonstrate the feasibility of HSV1-tk as a reporter gene and [8-14C]-ganciclovir as an imaging reporter probe. A good correlation (r2 = 0.86) between the [8-14C]-ganciclovir percent injected dose per gram tissue from HSV1-tk positive tissues and HSV1-TK enzyme levels in vivo was found. An initial study in mice with [8-18F]-fluoroganciclovir and microPET imaging supports further investigation of [8-18F]-fluoroganciclovir as a PET reporter probe for imaging HSV1-tk gene expression. CONCLUSION: These results demonstrate the feasibility of using [8-14C]-ganciclovir as a reporter probe for the HSV1-tk reporter gene, using an in vivo adenoviral mediated gene delivery system in a murine model. The results form the foundation for further investigation of [8-18F]-fluoroganciclovir for noninvasive and repeated imaging of gene expression with PET. 相似文献
959.
For estimating reliable exposure-response relations it is necessary that random variation in both the response and the exposure variables be sufficiently small. Variability in cumulative exposures can arise from uncertainties in self-reported work histories from interviews. In most epidemiologic surveys, the information gathered from questionnaires is used without knowing the validity or reproducibility of these data. This paper investigates the reliability of occupational histories reported by the same individuals on two occasions separated by 9 years in the US National Study of Coal Workers' Pneumoconiosis and its implications on the exposure-response relation for simple coal workers' pneumoconiosis. For 480 coal miners, from whom occupational histories were obtained twice (in 1969-1971 and 1977-1981), the reliability (intraclass correlation coefficient) of the cumulative exposures generated from each work history was 87%. Logistic model fitting of simple coal workers' pneumoconiosis prevalence to the cumulative coal dust exposure produced almost identical results. After accounting for intersurvey variability in the occupational histories, the authors found that the exposure-response coefficients estimated from information reported at the surveys were attenuated by 12%. In epidemiologic studies, knowledge of the reproducibility of self-reported occupational history information is important to ascertain whether the true exposure effect is underestimated. 相似文献
960.
T Whitwam ME Haskins PS Henthorn JN Kraszewski SE Kleiman NE Seidel DM Bodine JM Puck 《Canadian Metallurgical Quarterly》1998,92(5):1565-1575
Optimization of retroviral gene transfer into hematopoietic cells of the dog will facilitate gene therapy of canine X-linked severe combined immunodeficiency (XSCID) and in turn advance similar efforts to treat human XSCID. Both canine and human XSCID are caused by defects in the common gamma chain, gammac, of receptors for interleukin-2 and other cytokines. In this study, normal dogs were given retrovirally transduced bone marrow cells with and without preharvest mobilization by the canine growth factors granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF). Harvey sarcoma virus and Moloney murine leukemia virus constructs were used, both containing cDNA encoding human gammac. The Harvey-based vector transduced into cytokine-primed marrow yielded persistent detectable provirus in bone marrow and blood and expression of human gammac on peripheral lymphocytes. In three dogs, human gammac expression disappeared after 19 to 34 weeks but reappeared and was sustained, in one dog beyond 16 months posttransplantation, upon immunosuppression with cyclosporin A and prednisone, with up to 25% of lymphocytes expressing human gammac. The long-term expression of human gammac in a high proportion of normal canine lymphocytes predicts that retrovirus-mediated gene correction of hematopoietic cells may prove to be of clinical benefit in humans affected with this XSCID. This is a US government work. There are no restrictions on its use. 相似文献