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991.
A number of significant radiological pictures of spontaneous biliodigestive fistula are presented. The aetiopathogenesis, pathological anatomy and clinical medicine of the condition are reviewed and the techniques available for the radiological investigation of biliodigestive short-circuits considered; the most frequent radiological signs and corresponding pictures are discussed and the complications and differential diagnosis with duodeno-biliar reflow examined. 相似文献
992.
The effect of mammary gland expression of human lysozyme on the properties of milk from transgenic mice 总被引:1,自引:0,他引:1
Transgenic mice were used as model systems to evaluate the impact of human lysozyme expression in the mammary gland. We previously generated two lines of transgenic mice that express human lysozyme mRNA in the mammary gland under the tissue-specific and developmentally correct control of the bovine gene promoter for alpha s1-casein. Concentrations of human lysozyme protein in milk of transgenic mice varied from .25 to .71 micrograms/microliters of milk. Human lysozyme secreted into mouse milk retained its antimicrobial activity, as determined by a denaturing polyacrylamide gel activity assay. The physical and functional properties of the milk were also altered, because mouse milk containing human lysozyme had a 35% decrease in rennet clotting time, a smaller median micelle size (157 nm vs. 172 nm), and a 2.5- to 3-fold greater gel strength than control milk. From these results, we conclude that the use of transgenic animals producing lysozyme in the milk is feasible and potentially useful to the dairy industry. 相似文献
993.
A prospective study was undertaken to determine whether feeding farm animals antibiotics in feed caused changes in the intestinal bacterial flora of farm dwellers and their neighbors. Chickens were fed tetracycline-supplemented feed (tet-feed), and, as expected, within one week their intestinal flora contained almost entirely tetracycline-resistant organisms. Increased numbers of resistant intestinal bacteria also appeared, but more slowly, in farm members, but not their neighbors. Within five and six months, 31.3 per cent of weekly fecal samples from farm dwellers contained greater than 80 per cent tetracycline-resistant bacteria as compared to 6.8 per cent of the samples from the neighbors (P less than 0.001). Seven of the 11 farm members, but only three of the 24 neighbors, had two or more fecal samples containing greater than 80 per cent tetracycline-resistant coliforms (P less than 0.01). These resistant bacteria contained transferable plasmids conferring multiple antibiotic resistances. Selective pressure by tet-feed for antibiotic-resistant bacteria in chickens extends to human beings in contact with chickens and the feed. 相似文献
994.
Strain-2 inbred guinea pigs were infected intradermally with 10(5)-10(7) viable BCG (Pasteur) organisms by means of multiple scarifications of shaven midflank skin. The spread of the BCG to the draining lymph nodes and on to the spleen was followed quantitatively for 28 days. The population of bacilli at the inoculation site increased as much as tenfold the first 14 days. The number of viable BCG organisms recovered from the primary draining superficial dorsal axillary and inguinal lymph nodes varied from 0.1 to 1.0% of the inoculum, with a further tenfold to 100-fold drop in counts for the secondary subclavian and lumbar lymph nodes. The bacterial counts for the various nodes increased substantially the first 14 days. By 28 days, as many as 1,000 viable bacilli were recovered from the spleen. Increasing the inoculum size or the number of inoculation sites increased the primary node counts and promoted a more extensive and rapid spread by the BCG population to the secondary lymph nodes and spleen. Prior vaccination of the host with living BCG decreased the spread of the BCG inoculum from the scarification site to the various draining lymph nodes. Multiple injections of cortisone tended to reverse this effect. 相似文献
995.
K Kwan CE Coppock GB Lake MJ Fettman LE Chase RE McDowell 《Canadian Metallurgical Quarterly》1977,60(11):1706-1724
Thirty-nine lactating Holstein cows were fed high-energy complete rations ad libitum with crude protein: 1) 11.7% (negative control); 2) 13.9% (1% urea); 3) 16.6% (1% urea); or 4) 16.6% (positive control) in a continuous 12-wk study beginning at wk 5 postpartum. Milk production of 27.7, 31.8, 34.0, and 30.4 kg/day showed the use of urea nitrogen by groups 2 and probably 3. Two digestion-nitrogen balance trials with each cow also provided evidence that urea nitrogen was used for milk secretion. Energy digestibility averaged 59.4, 64.2, 65.4, and 65.8; and lower for the negative control diet. Nitrogen solubility in the diets was 28, 36, 32, and 21%, which reflects the objective of selecting ingredients with low nitrogen solubility for use in urea diets. Concentrations of ammonia nitrogen before and after feeding were 1.1, 3.3, 3.5, 4.2, and 2.2, 11.2, 11.9, and 9.3 mg/100 ml of rumen fluid. The prefeeding amounts were probably too low for maximum microbial growth. Urea-nitrogen concentrations in plasma were 8.65, 10.32, 18.00, and 17.03 mg/100 ml. These results lend support to the postulate that lactating cows in early lactation can use urea nitrogen when high-energy complete rations with ingredients of low nitrogen solubility are fed ad libitum. 相似文献
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999.
GB Schneider 《Canadian Metallurgical Quarterly》1976,146(1):93-100
A compound, isolated from acid hydrolysates of urine samples from normal children, characterized as 3,6-anhydroglucosamine by chromatography on a cation exchange resin and by gas-liquid chromatography, could not be detected in hydrolyses of urine from Morquio patients. 相似文献
1000.
LS Leshin RR Kraeling TE Kiser CR Barb GB Rampacek 《Canadian Metallurgical Quarterly》1995,37(4):351-358
Magnocellular perikarya within the retrochiasmatic division of the supraoptic nucleus of bovine and porcine hypothalami were immunoreactive (ir) with antiserum against tyrosine hydroxylase (TH), but not dopamine-beta-hydroxylase (DBH). Few cells in this region were also immunoreactive for vasopressin (VP) or oxytocin (OT). In contrast, the main division of the supraoptic nucleus contained numerous perikarya immunoreactive for VP and OT, but not TH nor DBH. Both the retrochiasmatic and principal divisions of the supraoptic nuclei contained TH- and DBH-ir fibers and varicosities. This region in bovine and porcine hypothalami corresponds to the ventral A15 catecholaminergic (dopamine-producing) cell group. 相似文献