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701.
Malignant mesothelioma occurred in a female Aborigine after environmental exposure to asbestos. All known cases of the disease in Aborigines in Western Australia were reviewed; all occurred in Pilbara residents. Most were exposed while involved in the transport of asbestos from the Wittenoom crocidolite operation. Based on recent estimates of the size of the Aboriginal population in the Pilbara region, their incidence of this disease (250 per million for ages 15 and over) is one of the highest population-based rates recorded.  相似文献   
702.
703.
Light-dark and temperature shifts performed on myxamoebal populations of mixed mating types indicate that there is early differentiation of the population leading to the macrocyst formation in Dictyostelium discoideum.  相似文献   
704.
Postprandial duodenal bile acids, intestinal protein loss, and albumin and IgG turnover were studied in 19 non-operated patients with Crohn's disease. A lesion of the terminal ileum was present in 18 of 19 patients, either alone or associated with regional colitis. Identical bile acid studies were made in a control group of 20 patients with chronic diarrhoea of undetermined origin. Duodenal bile acid concentration was decreased in 9 of 19 patients with Crohn's disease, and in 5 of 20 patients with unexplained diarrhoea. The glycine/taurine-ratio was increased in 8 of 17 patients with Crohn's disease, but in only one of the 20 control patients. Abnormal intestinal protein loss was present in 13 of 14 patients with Crohn's disease. The fractional catabolic rate of albumin and IgG was increased in all 17 cases of Crohn's disease studied, except the patient with no protein loss. A statistically significant and positive correlation was observed between glycine/taurine-ratio and fractional catabolic rate of both albumin and IgG. No patient with Crohn's disease harboured an abnormal bacterial flora in the proximal small intestine. It is concluded that, in the absence of abnormal bacterial flora in the proximal jejunum, the glycine/taurine-ratio is more valuable as an indicator of terminal ileopathy than postprandial duodenal bile acid concentration in nonoperated patients with terminal ileitis. Abnormal intestinal protein loss and increased catabolic rate of albumin and IgG are practically always present in active Crohn's disease and are strong evidence of an organic gastrointestinal lesion in patients with normal radiographic findings.  相似文献   
705.
This study examined whether arginine-vasopressin (A-VP), given before the test would produce an improved retrieval of aversive memory, in the same way as pre-exposure to inescapable footshocks, in rats. For this purpose animals conditioned in a T-maze with appetitive (10% sucrose) and aversive (2.0 mA footshock) events were administered (intracerebroventricular) a single dose of 2.5, 5, 10 or 20 ng/rat of A-VP, 20-min before testing. In the retention test conducted with the same training apparatus 72 h after conditioning, the peptide treated rats showed a dose-dependent increase in latencies to enter the previously shocked goalarm, with the absence of such a difference in responding to the non-shocked goalarm. This differential response was not observed in saline treated rats. This effect of peptide on memory retrieval was similar to that seen following inescapable footshock in rats. These results suggest the possible involvement of central vasopressinergic mechanisms in the differential enhancement of memory of helplessness condition.  相似文献   
706.
707.
In a variety of systems, histone mRNA has been shown to lack poly(A) (Adesnik and Darnell, 1972; Grunstein et al., 1973). We have found, however, that in Xenopus laevis oocytes, poly (A)-containing mRNA codes for histones, in a wheat germ cell-free system, based on the following criteria: first, co-migration with authentic X. laevis oocyte histones on polyacrylamide gels; second, no detectable incorporation of tryptophan; third, differential incorporation of lysine and methionine into histone fraction H2A; fourth, resistance of histone fraction H2A to cleavage with cyanogen bromide; and fifth, correspondence of tryptic peptide maps of partially purified cell-free products with authentic X. laevis oocyte histone. RNA which directs the synthesis of histones in the cell-free system is retained on oligo(dT)-cellulose, even after denaturation in 80% DMSO at 70 degrees C, thereby demonstrating the covalent attachment of polyadenylic acid sequences to the mRNA. Poly (A)- RNA (7S-14S fraction) was also found to code for histones using the same criteria. We discuss the significance of the finding that X. laevis oocytes contain two classes of histone mRNA as well as the potential developmental implications of this observation.  相似文献   
708.
Under outdoor conditions this model was over estimating sweat loss response in shaded (low solar radiation) environments, and underestimating the response when solar radiation was high (open field areas). The present study was conducted in order to adjust the model to be applicable under outdoor environmental conditions. Four groups of fit acclimated subjects participated in the study. They were exposed to three climatic conditions (30 degrees, 65% rh; 31 degrees C, 40% rh; and 40 degrees C, 20% rh) and three levels of metabolic rate (100, 300 and 450 W) in shaded and sunny areas while wearing shorts, cotton fatigues (BDUs) or protective garments. The original predictive equation for sweat loss was adjusted for the outdoor conditions by evaluating separately the radiative heat exchange, short-wave absorption in the body and long-wave emission from the body to the atmosphere and integrating them in the required evaporation component (Ereq) of the model, as follows: Hr = 1.5SL0.6/I(T) (watt) H1 = 0.047Me.th/I(T) (watt), where SL is solar radiation (W.m-2), Me.th is the Stephan Boltzman constant, and I(T) is the effective clothing insulation coefficient. This adjustment revealed a high correlation between the measured and expected values of sweat loss (r = 0.99, p < 0.0001).  相似文献   
709.
Different extensions of fuzzy c‐means (FCM) clustering have been developed to approximate FCM clustering in very large (unloadable) image (eFFCM) and object vector (geFFCM) data. Both extensions share three phases: (1) progressive sampling of the VL data, terminated when a sample passes a statistical goodness of fit test; (2) clustering with (literal or exact) FCM; and (3) noniterative extension of the literal clusters to the remainder of the data set. This article presents a comparable method for the remaining case of interest, namely, clustering in VL relational data. We will propose and discuss each of the four phases of eNERF and our algorithm for this last case: (1) finding distinguished features that monitor progressive sampling, (2) progressively sampling a square N × N relation matrix RN until an n × n sample relation Rn passes a statistical test, (3) clustering Rn with literal non‐Euclidean relational fuzzy c‐means, and (4) extending the clusters in Rn to the remainder of the relational data. The extension phase in this third case is not as straightforward as it was in the image and object data cases, but our numerical examples suggest that eNERF has the same approximation qualities that eFFCM and geFFCM do. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 817–841, 2006.  相似文献   
710.
Building energy simulation plays a significant role in building design and retrofit. Most applications deal with individual buildings which allow for the specification of detailed model inputs. However, building energy simulation can be a powerful tool for assessing energy performance even when comprehensive building characteristics are unavailable. In this study, limited field data were collected on randomly selected new homes in eight US states with a goal of evaluating energy code compliance and energy savings potential. The limited data do not allow the derivation of comprehensive model inputs for each individual home sampled, let alone for the entire unknown residential construction stock. Therefore, we used prototype buildings to construct a large number of models and utilized bootstrap sampling to draw inputs from the limited data. This research demonstrates that overall energy performance of a large population of new homes can be assessed by the novel framework, given limited data.  相似文献   
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