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981.
982.
We describe a five year old boy with inversion duplication of chromosome 15 (inv dup (15)) who, at the age of six months had started to develop West's syndrome. He later developed cryptogenic myoclonic epilepsy which was resistant to medication. On examination there was dysmorphia, overall hypotonia and diffuse pyramidalism. On starting ACTH the crises of flexion spasms were reduced but these were soon followed by myoclonic crises, both tonic and atonic, which did not respond to the various anticonvulsive treatments given. We comment on the changes in chromosome 15 linked to convulsions, and particularly the phenotypes of the inv dup (15) which depend on the size and genetic composition of the anomaly. This is the third case described in the literature of a patient with West's syndrome associated with supernumerary inversion duplication of chromosome 15. It is suggested that the karyotype be included when studying convulsive encephalopathies and cryptogenic refractory epilepsy, especially in infantile spasms. 相似文献
983.
984.
R Castejón JA Vargas M Briz E Berrocal Y Romero JC Gea-Banacloche MN Fernández A Durantez 《Canadian Metallurgical Quarterly》1997,11(8):1253-1257
We investigated whether 2-chlorodexoyadenosine could induce apoptosis in B cell chronic lymphocytic leukemia (B-CLL) cells in vitro using clinically achievable drug doses, measuring apoptosis ratio by flow cytometry. B cells were isolated from previously untreated patients and apoptosis was measured in these cells immediately after isolation and following incubation in vitro, without and with 2-chlorodeoxyadenosine at different concentrations, for 24 and 48 h. Distribution of cellular DNA content and quantitative analysis of apoptosis were determined by standard propidium iodide staining and flow cytometry. Spontaneous apoptosis occurred in B-CLL cells incubated in vitro in the absence of drug, but the level of apoptosis was greater in cells treated with 2-chlorodeoxyadenosine after the second day of culture. The present in vitro study of B-CLL cells from previously untreated patients suggests this chemotherapeutic agent activates a program of cell death by apoptosis using a drug dose equivalent to the physiological concentration used in patients in vivo. These data reveal an interesting possibility in the 2-chlorodeoxyadenosine treatment of untreated patients by neoplastic B cell apoptosis induction. 相似文献
985.
GA Velders JC Kluin-Nelemans CJ De Boer J Hermans EM Noordijk E Schuuring MH Kramer WA Van Deijk JB Rahder PM Kluin JH Van Krieken 《Canadian Metallurgical Quarterly》1996,14(4):1269-1274
PURPOSE: From a population-based non-Hodgkin's lymphoma (NHL) registry, 41 patients with mantle cell lymphoma (MCL) -- a recently defined distinct B-cell NHL -- were selected and compared with patients with low- or intermediate-grade NHL from the same registry. PATIENTS AND METHODS: The incidence and behavior of MCL in the area of the Comprehensive Cancer Center West (CCCW) from 1981 to 1989 were analyzed. Age, performance, tumor bulk, extranodal localization, stage, response to therapy, and survival were registered. Expression of cyclin D1 protein and Ki-67 were measured in 29 patients. RESULTS: MCL made up 3.7% of NHLs. The median age was 68 years, and the male-to-female ratio was 1.6:1. Seventy-eight percent presented with stage IV, with the majority having bone marrow involvement. The complete response (CR) rate was 32% (13 of 41), with a median duration of 25 months. The median overall survival time was 31.5 months. The International Prognostic Index identified five patients with a low-risk score and a median survival time of 93+ months. In 23 of 29 patients, cyclin D1 overexpression was present, without any relation to overall or disease-free survival. In contrast, a proliferative index less than 10% was significantly related to a better overall survival time (50 v 24 months). CONCLUSION: MCL is a disease of the elderly, who present with widespread disease and with a poor response to therapy. Although it harbors features of an indolent NHL, it behaves clinically as an aggressive NHL with a short overall survival time. 相似文献
986.
WP Farrar S Bech-Nielsen JC Gordon SM Reed CI Pretzman CW Kohn 《Canadian Metallurgical Quarterly》1993,34(4):345-353
A sulfate-reducing bacterium using trinitrotoluene (TNT) as the sole nitrogen source was isolated with pyruvate and sulfate as the energy sources. The organism was able to reduce TNT to triaminotoluene (TAT) in growing cultures and cell suspensions and to further transform TAT to still unknown products. Pyruvate, H2, or carbon monoxide served as the electron donors for the reduction of TNT. The limiting step in TNT conversion to TAT was the reduction of 2,4-diamino-6-nitrotoluene (2,4-DANT) to triaminotoluene. The reduction proceeded via 2,4-diamino-6-hydroxylaminotoluene (DAHAT) as an intermediate. The intermediary formation of DAHAT was only observed in the presence of carbon monoxide or hydroxylamine, respectively. The reduction of DAHAT to triaminotoluene was inhibited by both CO and NH2OH. The inhibitors as well as DANT and DAHAT significantly inhibited sulfide formation from sulfite. The data were taken as evidence for the involvement of dissimilatory sulfite reductase in the reduction of DANT and/or DAHAT to triaminotoluene. Hydrogenase purified from Clostridium pasteurianum and carbon monoxide dehydrogenase partially purified from Clostridium thermoaceticum also catalyzed the reduction of DANT in the presence of methyl viologen or ferredoxin, however, as the main reduction product DAHAT rather than triaminotoluene was formed. The findings could explain the function of CO as an electron donor for the DANT reduction (to DAHAT) and the concomitant inhibitory effect of CO on triaminotoluene formation (from DAHAT) by the inhibition of sulfite reductase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
987.
988.
989.
The myoneural junctions present in the opossum (Didelphis albiventris) extraocular muscles were studied through histochemical and ultrastructural techniques. Three different types of junction were shown: two single types, 'en grappe' and 'en plaque', present in the middle third of the muscle fibers; and one multiple type, more rare and observed in the distal third of the muscle. 相似文献
990.
The solution behaviour of selected proteins has been studied under conditions promoting precipitation, binding to mildly hydrophobic adsorbents or partition. Solvophobic theory may be used to describe these forms of protein partition. The tendency of a protein to partition therein is dependent upon surface properties of the protein solute mediated by the concentration and nature of added salts. As applied to partitioning in poly(ethylene glycol) (PEG)-salt systems this implies that linear (Br?nsted) relationships apply only to proteins partitioned close to the critical point. At longer tie-line lengths protein partitioning is increasingly influenced by salting-out forces. This is confirmed by the observed behaviour of the proteins. The point at which this behaviour changes has been unambiguously defined enabling the direct comparison of phase transition of proteins during partition in all systems. The results obtained show that phase transition during adsorption and partition occur at similar concentrations of salt. This is less than that required to promote precipitation. It appears, from these limited studies, that top-phase preferring proteins are partitioned at salt concentrations above those required to cause adsorption. Proteins preferring the lower phase are partitioned at salt concentrations close to or below those required for adsorption. This raises questions regarding the solvated molecular form of the partitioned proteins and the definition of the partition coefficient. 相似文献