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981.
MV Moura-Ribeiro CM Rocha WL Fernandes MM Guerreiro 《Canadian Metallurgical Quarterly》1993,51(4):507-510
The authors present the study of four children with arteritis as vascular complication of acute bacterial meningitis. They report pathophysiological mechanisms involved in vascular lesions, and progress in the understanding of these complications. 相似文献
982.
The incidental finding of microscopic foci of acantholytic dyskeratosis, reproducing the histological pattern of Darier's disease, has been the subject of a number of papers in the last few years. In contrast, the incidental finding of other types of acantholysis has not been mentioned in the literature. In the last 5 years, we have noticed such a microscopic finding in 14 biopsy specimens (0.15% of our cutaneous specimens). they were from 13 patients (7 men and 6 women); their ages ranged from 37 to 79 years (mean, 63). Three lesions were located on the head, 7 on the trunk, and 4 on the limbs. The histological diagnoses were basal cell carcinoma (6 cases), keratoacanthoma (2 cases), psoriasis (2 cases), elastolytic granuloma, acral arteriovenous angioma, tinea corporis, and leukocytoclastic vasculitis (1 case each). The histological patterns of the acantholytic foci simulated pemphigus vulgaris (9 cases), superficial pemphigus (1 case), Hailey-Hailey disease (3 cases), and unclassifiable acantholysis (1 case). None of the patients had familial or personal history of acantholytic disorders. We propose a classification of the primary acantholytic disorders based on both their acantholytic pattern and their clinical extent. 相似文献
983.
G Cimino F Lo Coco A Biondi L Elia A Luciano CM Croce G Masera F Mandelli E Canaani 《Canadian Metallurgical Quarterly》1993,82(2):544-546
Early infancy (< 1 year of age), massive tumor cell burden, and extremely poor prognosis are characteristic features of a particular subset of childhood acute leukemias (AL). In these cases, chromosome aberrations at the 11q23 band are the most frequently reported cytogenetic abnormalities. We have recently cloned a genetic locus named ALL-1, in which DNA breakpoints are clustered in leukemic patients with 11q23 aberrations. Analysis of the ALL-1 genomic configuration in DNA from 15 infants with AL showed specific ALL-1 rearrangements in 12 cases (80%), including 5 with normal karyotypes. These findings indicate that a consistent genetic defect underlies this particular leukemic subset. 相似文献
984.
CM Schmidt RG Ehlenfeldt MC Athanasiou LA Duvick H Heinrichs CS David HT Orr 《Canadian Metallurgical Quarterly》1993,151(5):2633-2645
Trophoblast, the only fetal tissue in direct contact with maternal cells, fails to express the polymorphic HLA class I molecules HLA-A and -B, but does express the nonpolymorphic class I molecule HLA-G. It is thought that HLA-G may provide some of the functions of a class I molecule without stimulating maternal immune rejection of the fetal semiallograft. As a first step in identifying the cis-acting DNA regulatory elements involved in the control of class I expression by extraembryonic tissue, several types of transgenic mice were produced. Two HLA-G genomic fragments were used, 5.7 and 6.0 kb in length. These included the entire HLA-G coding region, 1 kb of 3' flanking sequence, and 1.2 or 1.4 kb of 5' flanking sequence, respectively. A hybrid transgene, HLA-A2/G, was produced by replacing the 5' flanking sequence, first exon, and early first intron of HLA-G with the corresponding elements of HLA-A. Comparison of transgene mRNA expression patterns seen in HLA-A2/G and HLA-G transgenic mice suggests that 5' flanking sequences are largely responsible for the differing patterns of expression typical of the classical class I and HLA-G genes. Studies comparing the extraembryonic HLA-G expression levels of founder embryos transgenic for either the 5.7- or 6.0-kb HLA-G transgene showed that the 6.0-kb transgene directed HLA-G expression far more efficiently than did the 5.7-kb HLA-G transgene, producing extraembryonic HLA-G mRNA levels similar to those seen in human extraembryonic tissues. The results of these studies suggest that the 250-bp fragment present at the extreme 5' end of the 6.0-kb HLA-G transgene and absent from the 5.7-kb HLA-G transgene contains an important positive regulatory element. This 250-bp fragment lies further upstream than any of the previously documented class I regulatory regions and may function as a locus control region. 相似文献
985.
986.
[Correction Notice: An erratum for this article was reported in Vol 12(1) of Review of General Psychology (see record 2008-02668-007). On page 389, right column, last paragraph, the second to last sentence should read "The goal now, however, will be to improve students' success, faculty's scholarship, and the future of their communities". On page 386, right column, third paragraph, line six, "psychologist-administrators" should appear as "psychologist administrators". On page 390, right column, the Logue 2006 reference should read "[Survey of fields of Middle States Commission accredited New York State institutions of higher education chief academic officers and presidents]".] Higher education is currently facing many serious challenges. These challenges derive from the effects of globalization, massification (the wide availability of higher education), competition, expanding technology, regulation, litigation, and tuition increases that are outpacing student aid. Many psychologists possess the skills to overcome these challenges: to facilitate the learning, creativity, and performance of each student, faculty member, and staff member; foster productive group relations; analyze human behavior qualitatively, quantitatively, and experimentally; and generate and steward funds for their institutions. Psychologists are well prepared to lead institutions of higher education through and beyond their 21st-century challenges. Relatively few higher education leaders are psychologists, however. Psychologists should be encouraged to choose administrative career paths and thus greatly benefit our colleges and universities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
987.
G Sozzi S Tornielli E Tagliabue L Sard F Pezzella U Pastorino F Minoletti S Pilotti C Ratcliffe ML Veronese P Goldstraw K Huebner CM Croce MA Pierotti 《Canadian Metallurgical Quarterly》1997,57(23):5207-5212
Genomic alterations and abnormal expression of the FHIT gene at 3p14.2 have been observed in cell lines and primary tumors of the lung. To correlate FHIT locus DNA and RNA lesions with effects on Fhit protein expression, we have analyzed 11 lung cancer cell lines, 15 small cell lung carcinomas, and 38 pairs of non-small cell primary tumors and bronchial mucosa specimens by molecular genetic and immunocytochemical methods. Using specific antibodies against the Fhit protein, we observed concordance between RNA abnormalities and lack of Fhit protein expression in lung tumors and cell lines. In addition, absence of Fhit protein in some precancerous dysplastic lesions suggested that FHIT inactivation may occur at an early phase of lung carcinogenesis. 相似文献
988.
CM Chauve 《Canadian Metallurgical Quarterly》1997,39(4):393-395
INTRODUCTION: This review was performed to evaluate the outcome of patients undergoing pancreaticoduodenectomy (PD) for isolated metastatic or locally advanced nonperiampullary tumors at a single institution over a 13-year period. METHODS: Between 1983 and 1996, patients undergoing PD for metastatic or locally advanced nonperiampullary malignancies were identified. Medical records were reviewed and outcome factors and survival data analyzed. RESULTS: Eighteen patients were identified. The primary tumor histopathology included colon (n = 7), gastric (n = 4), renal cell (n = 3), lung (n = 2), bladder (n = 1), and melanoma (n = 1). The median length of hospital stay was 15 days (6 to 48) with one perioperative death (5.5%). The median tumor size was 5.5 cm (0.8 to 11.5), and 7 patients had positive peripancreatic lymph nodes. The median survival was 40 months, with a 5-year survival of 35%. CONCLUSIONS: Pancreaticoduodenectomy for nonperiampullary malignancy is infrequently indicated. However, in the absence of widely metastatic disease, PD should be considered for locally advanced tumors or isolated metastatic malignancy. 相似文献
989.
Cell-cell adhesion mediated by E-cadherin is often lost or disturbed in human carcinomas. For regular adhesive function, E-cadherin has to form complexes with peripheral cytoplasmic catenins which are multifunctional proteins that are also involved in signal transduction and growth regulation. We have analyzed the expression levels of the genes encoding alpha-catenin, beta-catenin and plakoglobin in correlation to the E-cadherin expression levels in cell lines derived from human cervical carcinomas. Reduced mRNA and protein levels were detected for plakoglobin, whereas alpha- and beta-catenin showed only reduced protein (but not mRNA) levels. The alterations in catenin gene expression were often associated with absent or reduced E-cadherin. The findings indicate that a reduction of catenin gene expression may contribute to the development of cervical carcinomas. 相似文献
990.
Tissue ingrowth into porous-coated orthopedic and dental implants is commonly used as a means to achieve long-term fixation of these prostheses. However, the degree of tissue ingrowth is often inadequate and inconsistent. If the pores of these implants are impregnated with a controlled drug release system delivering relevant growth factors, then it might be possible to stimulate more tissue ingrowth. The present study introduces such a system based on biodegradable polymers and investigates its protein release profile and polymer degradation characteristics. Porous coated titanium implants were impregnated with a mixture of a 50%-50% polylactic acid-polyglycolic acid copolymer and a model protein, soybean trypsin inhibitor. Control implants contained only the polymer and no protein. The implants were subjected to hydrolytic degradation in phosphate buffered saline at 37 degrees C for periods of 3, 6, and 11 weeks. The protein release and the mass and molecular weight of the polymer were monitored. The results indicate that the protein is released in three distinct phases and the polymer loses almost all its mass and molecular weight by 11 weeks. There was a significant difference in the polymer degradation characteristics between the control and test implants, which might be the result of some complex polymer-protein interactions. 相似文献