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71.
Soranos was highly regarded as the first and the most famous gynecologist in the antiquity. In point of fact, Soranos was not really a gynecologist but, he was the first to write a treatise about "gynecology". This work came down to us incomplete. In this study we analyse the conception's theories of Soranos. 相似文献
72.
DA Gansler R Fucetola M Krengel S Stetson R Zimering C Makary 《Canadian Metallurgical Quarterly》1998,186(12):776-781
There has been increasing knowledge of the treatment, diagnosis, and demographics of adults with residual attention deficit/hyperactivity disorder (ADHD). However, less is known about the neuropsychological functioning in adults with residual ADHD. In comparing the clinical neuropsychological test performance of a group of adult clinic patients with residual ADHD (N = 30) with that of normal controls (N = 10), we found the patients performed worse on the Trail Making Test, a visual continuous performance test, and the "Brown-Peterson" Auditory Consonant Trigrams Test, but not on any other neuropsychological measures. This pattern indicated a deficit in the area of executive control type functioning, a functional deficit that could be linked to dysregulation of frontal lobe brain systems. Of equal interest was that patients diagnosed with ADHD/hyperactive impulsive type (ADHD+) and patients diagnosed with ADHD/inattentive type (ADHD-) had different types of executive system deficits. ADHD+ was associated with relative deficiency on the Wisconsin Card Sorting Test. ADHD- was associated with relative deficiency on the "Brown-Peterson" Auditory Consonant Trigrams Test, a measure of working memory, as well as less olfactory identification on a smell identification test. The data are discussed in terms of recent localization theories of frontal lobe function. The preliminary data suggest that the different cognitive weaknesses of ADD subtypes may be linked to dysregulation of separate frontal brain regions and/or neurotransmitter systems. 相似文献
73.
A Edmar A Lombès M Renouil A Bangui D Lamblin B Boumahni G Chaurand JB Mariette A Fourmaintraux L Vallee 《Canadian Metallurgical Quarterly》1998,5(9):1000-1003
BACKGROUND: MELAS syndrome is a rare mitochondrial cytopathy; its diagnosis can be difficult. CASE REPORT: A 6-month-old boy presented with febrile seizures, possibly due to viral meningitis. At 7 months, he developed myoclonia and "brain attacks" and, subsequently, myoclonical attacks, regression of psychomotor and mental acquisitions, and progressive visual loss. The ratio of lactatorachia/lactacidemia was increased. The molecular genetic analysis showed an heteroplasmic point mutation with A-to-G mutation at nucleotide 3243 of the mitochondrial tRNA(leu) (UUR) gene. He was the second child of a mother having frequent headaches. His great aunt, a sister of his maternal grandmother, was mentally retarded and had frequent epileptic seizures and hemiparesy since her childhood. CONCLUSION: Any unusual neurological symptom, particularly when combined with "illegitimate" symptoms, should lead to search for a mitochondrial cytopathy. 相似文献
74.
JB Hale JA Hoeppner MB DeWitt DL Coury DG Ritacco B Trommer 《Canadian Metallurgical Quarterly》1998,31(6):595-607
We introduce a novel application for linkage analysis: using bone marrow donor-recipient sib pairs to search for genes influential in graft-versus-host disease (GVHD), a major cause of morbidity and mortality following allogeneic bone marrow transplantation. In particular, we show that transplant sib pairs in which the recipient developed severe GVHD can be used to map genes in the same way as traditional discordant (affected/unaffected) sib pairs (DSPs). For a plausible GVHD model, we demonstrate that the transplant/discordant sib pair analog of the "possible triangle test" [Holmans (1993) Am J Hum Genet 52:362-374] has similar power to that of the simpler "restricted test" proposed by Risch [(1990b) Am J Hum Genet 46:229-241; (1992) Am J Hum Genet 51:673-675]. Moreover, we show that the restricted test has superior power in much of the DSP possible triangle and significantly inferior power in only a small region. Thus, we conclude that the restricted test is preferable for localizing genes with transplant/discordant sib pairs. Finally, we examine the effects of heterogeneity on the power to detect GVHD loci and demonstrate the gain in efficiency by dividing the sample into genetically more homogeneous subgroups. 相似文献
75.
S Hicks G Frankel JB Kaper G Dougan AD Phillips 《Canadian Metallurgical Quarterly》1998,66(4):1570-1578
Attaching and effacing (A/E) lesion formation is central to enteropathogenic Escherichia coli (EPEC) pathogenesis. In vitro experiments with human epithelial cell lines have implicated virulence plasmid-encoded bundle-forming pili (BFP) in initial binding and intimin in intimate attachment and A/E lesion formation. This study investigated the role of BFP and intimin in EPEC interactions with pediatric small intestinal biopsy tissue in in vitro organ culture. Organ culture infections (2 to 8 h) were performed with E2348/69 (a wild-type EPEC O127:H6 clinical isolate) and E2348/69 derivatives including CVD206 (eae deficient), CVD206(pCVD438) (eae-complemented CVD206), CVD206(pCVD438/01) (expressing intimin, which is nonfunctional due to a single amino acid substitution), JPN15 (spontaneous EPEC adherence factor virulence plasmid-cured E2348/69), and 31-6-1(1) (E2348/69 with a TnphoA insertion inactivation mutation in the virulence plasmid-encoded bfpA gene). Scanning and transmission electron microscopy revealed that after 8 h E2348/69 and CVD206 (pCVD438) (both Int+ BFP+) adhered to all specimens, causing A/E lesions with surrounding microvillous elongation. JPN15 and 31-6-1(1) (both Int+ BFP-) adhered and caused A/E lesions although bacteria adhered in "flat," two-dimensional groups. CVD206 and CVD206(pCVD438/01) (both Int- BFP+) did not adhere to any sample, and no pathological tissue changes were seen. Thus, in human intestinal organ culture, BFP do not appear to be involved in the initial stages of EPEC nonintimate adhesion but are implicated in the formation of complex, three-dimensional colonies via bacterium-bacterium interactions. Intimin appears to play an essential role in establishing colonization of EPEC on pediatric small intestinal tissue. 相似文献
76.
JB Bederson AL Levy WH Ding R Kahn CA DiPerna AL Jenkins P Vallabhajosyula 《Canadian Metallurgical Quarterly》1998,42(2):352-60; discussion 360-2
OBJECTIVE: Decreased cerebral blood flow (CBF) and cerebral ischemia occurring immediately after subarachnoid hemorrhage (SAH) may be caused by acute microvascular constriction. However, CBF can also be influenced by changes in intracranial pressure (ICP) and cerebral perfusion pressure (CPP). The goal of these experiments was to assess the significance of acute vasoconstriction after SAH and its relationship to changes in CBF, ICP, CPP, and extracellular glutamate concentrations. METHODS: Three experiments were performed using the endovascular filament technique to produce SAH. In the first experiment, CBF, ICP, and CPP were measured for 60 minutes after SAH (n = 21) and were correlated with the 24-hour mortality rate. In the second experiment, rats undergoing SAH (n = 23) or a sham procedure (n = 7) were perfused 60 minutes after SAH for measurement of the circumference and wall thickness of the internal carotid and anterior cerebral arteries and correlation with CBF, ICP, and CPP. In the third experiment (n = 11), extracellular glutamate concentrations determined by hippocampal and cortical microdialysis and high performance liquid chromatography were correlated with physiological changes. RESULTS: CBF reductions to less than 40% of baseline for 60 minutes after SAH predicted 24-hour mortality with 100% accuracy and were used to define "lethal" SAH. In contrast, ICP and CPP 60 minutes after SAH were not correlated with the mortality rate. The vascular circumference was significantly smaller in lethal than in sublethal SAH or sham-operated rats (P < 0.001). Vessel measurements were correlated with both CBF and hemorrhage size (P < 0.01). Extracellular glutamate concentration increased to 600% of baseline after lethal SAH in both hippocampus and cortex and was inversely correlated with CBF (r = 0.9, P < 0.001) but did not increase after sublethal SAH. CONCLUSION: Acute vasoconstriction after SAH occurs independently of changes in ICP and CPP and is associated with decreased CBF, larger hemorrhage size, persistent elevations of extracellular glutamate, and poor outcome. Acute vasoconstriction seems to contribute directly to ischemic brain injury after SAH. Further evaluations of pharmacological agents with the potential to reverse acute vasoconstriction may increase CBF and improve outcome. 相似文献
77.
TV holograms for spatial phase stepping are formed with a small angular offset between the object and the reference beams to give a spatial frequency bias to the pattern recorded by the TV camera. It is common to set the bias so that there is a 90° or 120°phase shift between adjacent pixels and to use the irradiance of three or more adjacent pixels to evaluate the phase of the interference. We report the Fourier-transform evaluation of such recordings to obtain their phase data. We also demonstrate the direct calculation of the phase difference between successive recordings without intermediate calculation of the random phase of each hologram. This technique is proposed as an approach to pulsed TV holography. 相似文献
78.
Novel unitary devices, prepared by lyophilization of viscous solutions of sodium carboxymethylcellulose (CMC) and methylcellulose (MC), were evaluated as sustained-release delivery systems for recombinant human bone morphogenetic protein-2 (rhBMP-2). In vitro characterization of the unitary devices, which contained rhBMP-2-loaded poly (d,l lactide-co-glycolide) (PLGA) bioerodible particles (BEPs), was conducted over a 2-month period. Determinations included buffer uptake, mass and molecular weight loss and rhBMP-2 release from the unitary devices. CMC devices imbibed approximately 16 times their weight of buffer, while with MC, equilibrium uptake was approximately 6 times the dry weight of the devices. Overall mass loss percentages were approximately 55 and 35%, respectively, for CMC and MC devices. rhBMP-2 release from the devices was essentially a triphasic process: an initial phase during which "free" protein (rhBMP-2 present on the surface and within the pores of the PLGA BEPs) was released, a lag period during which no release was discerned, and then release of "bound" rhBMP-2 (protein adsorbed to the BEPs). The release of bound protein correlated with the mass loss of the polymer which began after 3 weeks. Release from the unitary devices was lower than that from the BEPs alone, due to a retardation effect of the gelled CMC/MC polymers. In rabbits in which full-thickness cranial bone defects were created, the implants were well tolerated and induced significant new bone growth during an 8-week evaluation period. The CMC devices appear to have induced bone earlier (at 2 weeks), but this did not affect eventual 8-week results. CMC devices without rhBMP-2 appeared to provide some bone conduction, in contrast to the blank MC devices. 相似文献
79.
F Devin P Garcia V Peyrot B Ridings JB Saracco 《Canadian Metallurgical Quarterly》1996,19(6-7):423-430
PURPOSE: The function of RPE is well known in PVR. Pharmacological agents have been extensively studied both experimentally and clinically. Few reports have detailed the interactions of antimitotic drugs on the microtubule network. The aim of this study is to visualize by indirect immunofluorescence the effects of colchicine and paclitaxel on the microtubule network of cultured pig RPE cells in interphase. METHODS: Pigs were killed at the slaughter-house, their eyes were enucleated. RPE cells were isolated and cultured. RPE cells were plated onto glass cover-slips at a density of 2,000,000 cells/ml, cultured and treated with the drugs during 4 and 24 hours at 37 degrees C at different concentrations. Immunofluorescence reaction was developped using antitubulin and fluoresceinated anti-mouse antibodies. The cytoskeletons were visualized employing a Zeiss photomicroscope equipped with epiilumination, a 63 x lens and appropriate filters for fluoresceine. RESULTS: The cytoplasmic microtubules of RPE cells were disrupted in a concentration and time-dependant manner by colchicine. Between 10 and 100 nm Veveral degrees of depolymarization of the microtubule network were observed. Paclitaxel between 1 micron and 10 microns was found to induce several degrees of microtubule "bundling" after 4 and 24 hours of incubation. Actin network was modified neither by colchicine and paclitaxel used in the same conditions. CONCLUSIONS: The results show that low doses of antimitotic drugs inhibit the microtubule network formation by depolymerization (colchicine) or stabilize it (paclitaxel). These actions inhibit cell division, which is one of the mechanisms implicated in PVR. 相似文献
80.
J Iida AM Meijne JR Knutson LT Furcht JB McCarthy 《Canadian Metallurgical Quarterly》1996,7(3):155-162
Genes that encode enzymes that convert inactive "prodrugs" into anticancer metabolites may be therapeutically useful against brain tumors. Unlike other genes tested to date in brain tumor models, the Escherichia coli gpt gene is unique in that it not only sensitizes cells to the prodrug 6-thioxanthine (6TX) but also encodes resistance to a different regimen (mycophenolic acid, xanthine, and hypoxanthine), thus providing a means to select for gpt-positive cells. In the present study, rat C6 glioma cells were infected with a retrovirus vector that transduces this gene. A clonal line (C6GPT-7) was derived that exhibited significant 6TX susceptibility in vitro with an ID50 of 2.5 mumol/L, whereas 50% growth inhibition of parental C6 cells was not achieved at concentrations tested (up to 50 mumol/L). This line also exhibited significant sensitivity to 6-thioguanine (6TG), with an ID50 of 0.05 mumol/L, whereas 50% growth inhibition of parental C6 cells was achieved at 0.5 mumol/L. In a "bystander" assay, C6GPT-7 tumor cells efficiently transferred 6TX sensitivity to C6 cells at ratios as low as 1:9 (C6GPT-7:C6). This in vitro bystander effect was abrogated when C6GPT-7 and C6 cells were separated by a microporous membrane, suggesting that it was not mediated by highly diffusible metabolites. In vivo both 6TX and 6TG significantly inhibited the growth of subcutaneously transplanted C6GPT-7 cells but not that of C6 cells in athymic mice. In an intracerebral model, both 6TX and 6TG exhibited significant antiproliferative effects against tumors formed by C6GPT-7 cells. These findings provide a basis for exploring further gene therapy strategies based on in vivo transfer of the E coli gpt gene to provide chemosensitivity against 6TX and 6TG. 相似文献