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JK Iversen H Nelleman A Buus K Stengaard-Pedersen U Lucht O Myhre Jensen AG Jurik 《Canadian Metallurgical Quarterly》1996,25(4):396-399
Calciphylaxis is a rare condition of widespread calcification of tissues and blood vessels with accompanying vascular thrombosis and ischemic necrosis. Most cases develop in association with hyperparathyroidism in patients with chronic renal failure. Pseudoxanthoma elasticum (PXE) is a hereditary condition of abnormal elastic tissue structure that leads to widespread abnormalities of the skin, retina, and visceral organs. Histologic changes of PXE have been observed as coincidental findings in several conditions such as following trauma to the skin manifest as isolated plaques often in scars. We observed histologic findings of PXE in a patient with chronic renal failure who developed fatal calciphylaxis. Complete evaluation failed to reveal evidence of systemic findings of PXE. Histologic changes of PXE may be seen in patients with calciphylaxis as a coincidental finding. Rapidly developing soft tissue calcification may lead to the expression of the characteristic histopathologic findings of PXE without evidence of classic clinical manifestations of PXE. Calciphylaxis should be added to the list of disorders that may lead to microscopic PXE-like changes. 相似文献
204.
In metazoan cells, the CAS protein has been shown to function as a recycling factor for the importin-alpha subunit of the classical nuclear localization signal receptor, exporting importin-alpha from the nucleus to allow its participation in multiple rounds of nuclear import. CAS is a member of a family of proteins that bear homology to the larger subunit of the nuclear localization signal receptor, importin-beta, and that are found in all eukaryotes from yeast to humans. Sequence similarity identifies the product of the Saccharomyces cerevisiae CSE1 gene as a potential CAS homologue. Here we present evidence that Cse1p is the functional homologue of CAS: Cse1p is required to prevent accumulation of Srp1p/importin-alpha in the nucleus, it localizes to the nuclear envelope in a pattern typical of nuclear transport receptors, and it associates in vivo with Srp1p in a nucleotide-specific manner. We show further that mutations in CSE1 and SRP1 have specific effects on their association and on the intracellular localization of Cse1p. 相似文献
205.
MD Phillips RI Grossman Y Miki L Wei DL Kolson MA van Buchem M Polansky JC McGowan JK Udupa 《Canadian Metallurgical Quarterly》1998,19(6):1055-1060
A kinetic analysis of degradation of saturated oligoguluronates by poly(alpha-L-guluronate)lyase from Corynebacterium sp. ALY-1 strain was done. The saturated oligoguluronates were prepared by hydrolyzing poly alpha-1,4-L-guluronate from alginate with HCl, and then by gel filtration on a Bio-Gel P-6 column. The saturated pentaguluronate or above were rapidly degraded by the enzyme, while tetraguluronate was slowly degraded. From the dependency of the catalytic rate constant (kcat) on the degree of polymerization of substrates, the enzyme was found to have a subsite size corresponding to hexaguluronate units. The action pattern of the enzyme on hexaguluronate suggested that the catalytic site of the enzyme was matched to the linkage between the second and third uronic residue from the non-reducing end, since the substrate was mainly split into a unsaturated tetramer and a saturated dimer from a HPLC analysis. 相似文献
206.
We have developed a new mixed-dye protein staining method that is simple, rapid, and sensitive. A freshly prepared mixture of calconcarboxylic acid (NN, 0.02%) and rhodamine B (RB, 0.04%) in 40% methanol/7% acetic acid, was used as a staining solution. RB acts as an auxiliary agent to inhibit the binding of NN to the gel matrix, reducing the background staining and therefore enhancing the protein staining by NN. This mixed-dye staining method reduces the total staining and destaining time to less than an hour, and increases the sensitivity to 25 ng of bovine serum albumin, which is greater than the 100 ng sensitivity limit of Coomassie Brilliant Blue R-250 (CBBR) staining. 相似文献
207.
RS Clark PM Kochanek MA Schwarz JK Schiding DS Turner M Chen TM Carlos SC Watkins 《Canadian Metallurgical Quarterly》1996,39(5):784-790
The inflammatory response after traumatic brain injury (TBI) includes cytokine production, leukocyte infiltration, and microglial activation. Production of nitric oxide by inducible nitric oxide synthase (iNOS) occurs during acute inflammation outside of the CNS and in models of cerebral ischemia, and therefore may contribute to the inflammatory response after TBI. The purpose of this study was to localize and define the time course of iNOS expression after TBI in the immature rat. Immature Wistar rats (age 3.5-4.5 wk) were anesthetized and subjected to percussive trauma to the right parietal cortex. Nontraumatized rats were used as controls (n = 7). At 2, 24, 48, or 168 h (n = 3/group) posttrauma rats were killed by perfusion fixation. Brains were removed, frozen, sectioned, immunostained with antibodies against iNOS and glial fibrillary acidic protein (GFAP, a marker specific for astrocytes), and imaged using fluorescent detection systems. There was no detectable expression of iNOS in control brains. At 2h, minimal cerebrovascular iNOS expression was seen in the peritrauma area. At 24 and 48 h, there was marked peritrauma cerebrovascular iNOS expression that appeared to be restricted to vascular smooth muscle cells and infiltrated leukocytes. Further dual-immunolabeling showed that the leukocytes expressing iNOS were predominantly neutrophils. At 168 h, iNOS expression was no longer detectable. iNOS was not detectable in GFAP-positive cells. The prominent expression of iNOS protein after TBI in cerebrovascular smooth muscle cells and infiltrated neutrophils suggests that iNOS may play a role in cerebrovascular disturbances and secondary brain injury after trauma. 相似文献
208.
To understand the role of the spectrin-based membrane skeleton in generating epithelial polarity, we characterized the distribution of membrane skeletal components in Drosophila ovarian follicle cells and in somatic clones of mutant cells that lack alpha-spectrin. Immunolocalization data reveal that wild-type follicle cells contain two populations of spectrin heterodimers: a network of alphabeta heterodimers concentrated on the lateral plasma membrane and an alphabetaH population targeted to the apical surface. Induction of somatic clones lacking alpha-spectrin leads to follicle cell hyperplasia. Surprisingly, elimination of alpha-spectrin from follicle cells does not appear to prevent the assembly of conventional beta-spectrin and ankyrin at the lateral domain of the follicle cell plasma membrane. However, the alpha-subunit is essential for the correct localization of betaH-spectrin to the apical surface. As a consequence of disrupting the apical membrane skeleton a distinct sub population of follicle cells undergoes unregulated proliferation which leads to the loss of monolayer organization and disruption of the anterior-posterior axis of the oocyte. These results suggest that the spectrin-based membrane skeleton is required in a developmental pathway that controls follicle cell monolayer integrity and proliferation. 相似文献
209.
Stroke is the third most common cause of death in Britain, but despite its medical and economic importance, management of the three facets of stroke--prevention, acute care and rehabilitation--has been unstructured and poor value for money. This article considers how these issues might be more effectively addressed by a pragmatic coordinated approach to the whole problem of stroke in a health authority. 相似文献
210.
For survivors of aneurysmal subarachnoid hemorrhage, cerebral vasospasm significantly contributes to its morbidity and mortality by causing delayed ischemic neurological deficit. Noninvasive evaluation with computed tomography, transcranial doppler and single photon emission computerized tomography helps guide clinical decisions. Endovascular therapy of symptomatic vasospasm with balloon angioplasty and to a lesser extent with intraarterial papaverine infusion has emerged as an important treatment adjunct to neurosurgical medical and operative management. Early and aggressive treatment with balloon angioplasty has resulted in sustained clinical improvement in about two-thirds of patients suffering from neurological deficits attributable to vasospasm. Encouraging long-term clinical and transcranial artery damage following angioplasty. Despite balloon angioplasty's 2% to 5% peri-procedure mortality rate, it remains under used. 相似文献