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101.
102.
LM Vieira da Silva VL Formigli MP Cerqueira L Kruchevsky 《Canadian Metallurgical Quarterly》1997,1(6):444-450
To evaluate vaccination coverage in children 0 to 5 years of age, a cross-sectional study based on a household survey was carried out in 1992 in the Pau de Lima Health District, Salvador, Bahia, Brazil, using a cluster sampling technique. The district was subdivided into 30 small areas that were homogeneous with respect to socioeconomic characteristics. Information on the vaccination status of 385 children was obtained through verification of a vaccination card or campaign voucher, or, in the absence of these items, through verbal confirmation from the mother or other responsible person. Based on all the sources of information, the study found vaccination coverage rates in the entire age range of 69% for polio vaccine; 56% for DTP; 74% for measles vaccine; and 87% for BCG. These results suggest that rates obtained from routine records of the health services and vaccination campaigns may be overestimates. The authors discuss the implications of the low coverage rates found in the entire age group and especially among children under 1 year old. 相似文献
103.
OBJECTIVE: To describe the prevalence of and risk factors associated with regular water supplementation of neonates. DESIGN: Evaluation of data from the Food and Drug Administration's Infant Feeding Practices Study, a panel study of US women of fairly high socioeconomic status who were followed up from late pregnancy through their infants' first year of life. The sample was drawn from a nationally distributed consumer mail panel. Each mother was asked whether she gave her neonate water at least 3 times per week. PARTICIPANTS: A total of 1677 mothers of infants who were neonates in April through November 1993. MAIN OUTCOME MEASURES: Percentages of mothers who gave their neonates water at least 3 times a week, considering infant feeding status, mother's education, and family income. RESULTS: About one fourth (24.7%) of the mothers reported giving their neonates water at least 3 times per week. Stratification by feeding practices and socioeconomic factors revealed that 41.6% of mothers who formula-fed their neonates, 47.4% of mothers with less than a high school education, and 35.4% of mothers with an annual family income less than $22,500 gave their neonates water at least 3 times per week. CONCLUSIONS: Water supplementation of neonates was a prevalent practice in this cohort of women. Feeding practices, maternal education, and family income were all significant risk factors associated with this behavior. 相似文献
104.
105.
EJ Gangarosa AM Galazka CR Wolfe LM Phillips RE Gangarosa E Miller RT Chen 《Canadian Metallurgical Quarterly》1998,351(9099):356-361
To assess the impact of anti-vaccine movements that targeted pertussis whole-cell vaccines, we compared pertussis incidence in countries where high coverage with diphtheria-tetanus-pertussis vaccines (DTP) was maintained (Hungary, the former East Germany, Poland, and the USA) with countries where immunisation was disrupted by anti-vaccine movements (Sweden, Japan, UK, The Russian Federation, Ireland, Italy, the former West Germany, and Australia). Pertussis incidence was 10 to 100 times lower in countries where high vaccine coverage was maintained than in countries where immunisation programs were compromised by anti-vaccine movements. Comparisons of neighbouring countries with high and low vaccine coverage further underscore the efficacy of these vaccines. Given the safety and cost-effectiveness of whole-cell pertussis vaccines, our study shows that, far from being obsolete, these vaccines continue to have an important role in global immunisation. 相似文献
106.
Nuclear medicine imaging techniques are an important adjunct to other currently used modalities in the evaluation of patients with fever of unknown origin. Bone scanning performed with technetium-labeled phosphonate agents may identify osteomyelitis when plain radiography fails and may disclose sites of joint inflammation or unsuspected osseous tumor metastasis. Indium-labeled autologous leukocytes localize at sites of inflammation in the same manner as unlabeled leukocytes. Gallium citrate accumulates in areas of inflammation and in some tumors, most notably lymphomas. In most cases, scintigraphy is best used to determine the location of a lesion rather than to specifically identify the pathologic process. 相似文献
107.
108.
The putative envelope glycoproteins of hepatitis C virus (HCV) likely play an important role in the initiation of viral infection. Available information suggests that the genomic regions encoding the putative envelope glycoproteins, when expressed as recombinant proteins in mammalian cells, largely accumulate in the endoplasmic reticulum. In this study, genomic regions which include the putative ectodomain of the E1 (amino acids 174 to 359) and E2 (amino acids 371 to 742) glycoproteins were appended to the transmembrane domain and cytoplasmic tail of vesicular stomatitis virus (VSV) G protein. This provided a membrane anchor signal and the VSV incorporation signal at the carboxy termini of the E1 and E2 glycoproteins. The chimeric gene constructs exhibited expression of the recombinant proteins on the cell surface in a transient expression assay. When infected with a temperature-sensitive VSV mutant (ts045) and grown at the nonpermissive temperature (40.5 degrees C), cells transiently expressing the E1 or E2 chimeric glycoprotein generated VSV/HCV pseudotyped virus. The resulting pseudotyped virus generated from E1 or E2 surprisingly exhibited the ability to infect mammalian cells and sera derived from chimpanzees immunized with the homologous HCV envelope glycoproteins neutralized pseudotyped virus infectivity. Results from this study suggested a potential functional role for both the E1 and E2 glycoproteins in the infectivity of VSV/HCV pseudotyped virus in mammalian cells. These observations further suggest the importance of using both viral glycoproteins in a candidate subunit vaccine and the potential for using a VSV/HCV pseudotyped virus to determine HCV neutralizing antibodies. 相似文献
109.
In 4 conditioned lick suppression experiments with rats, the combined effects of latent inhibition treatment followed by overshadowing treatment were assessed as a test of the comparator hypothesis's (R.R. Miller & L.D. Matzel, 1988) explanations of overshadowing and latent inhibition. Experiments 1 and 2 confirmed the prediction of the comparator hypothesis that combined latent inhibition and overshadowing treatments attenuate the response deficit produced by either treatment alone. Furthermore, consistent with the comparator hypothesis, posttraining changes in the associative status of the putative comparator stimulus altered responding to the target conditioned stimulus (Experiment 3), and switching contexts between latent inhibition and overshadowing treatments (Experiment 4) eliminated the interaction between the latent inhibition and overshadowing treatments. 相似文献
110.
JM Quintela C Peinador C Veiga L González LM Botana A Alfonso R Riguera 《Canadian Metallurgical Quarterly》1998,6(10):1911-1925
The synthesis of a series of pyridothienopyrimidines and their evaluation as inhibitors or inducers of the release of histamine from rat mast cells is reported. The activity was measured after immunological stimulation with ovoalbumin and chemical stimulation with polymer 48/80 and the drugs adryamicin and vinorelbine. The experiments were carried out with and without preincubation of the stimulus with the cells before addition of the drug. Several pyridothienopyrimidines show inhibitory IC50 values in the range 2-25 microM, indicating they are up to 100 times more potent than cromoglycate (DSCG) and 10 times greater than Ketotifen. Compound 9l is a potent inhibitor in all the conditions tested and shows IC50 = 9-25 microM. Pyridothienopyrimidines 4l and 9e are very strong inducers of histamine release in the immunological (4l, 170-230%) and chemical (9e, 100-150%) assays, respectively. Compounds 4l and 9i are cytotoxic in vitro (IC50 = 0.1-0.2 microgram/mL) against P-388, A-549, HT-29, and MEL-28 tumor cell lines. 相似文献