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151.
152.
Pseudomonas fluorescens multiplied in a minimal mineral medium supplemented with millimolar amounts of aluminum (5 mM), iron (5 mM), zinc (3 mM), calcium (2 mM) and gallium (1 mM). A slight decrease in growth rate and a 22% diminution in cellular yield were observed as compared to the control medium. Citrate, the sole source of carbon to which the test metals were complexed, was completely utilized. Although at stationary phase of growth most of the metals were immobilized in an exocellular lipid-rich residue, ultracentrifugation and dialysis studies revealed that metals were associated with phosphatidylethanolamine (PE) from early stages of growth. As growth progressed the metal content of the soluble cellular extract increased reaching an optimum at 35 h of incubation. However, no detectable amounts of metals in this cellular component were discerned at stationary phase of growth. There appeared to be no marked variation in exocellular protein and carbohydrate production in control and metal-stressed cultures. Transmission electron microscopic studies revealed metal rich bodies associated with the cytoplasm. Scanning electron microscopic analyses of the dialyzate aided in the identification of the metal-rich bodies associated with elongated structures comprised of carbon, oxygen and phosphorus. PE appeared to be an important organic constituent of the gelatinous residue.  相似文献   
153.
154.
Hypoglycemia is a common problem among neonates. Transient in nature, it usually resolves with an increase in glucose intake. However, as clinicians, we must recognize that prolonged hypoglycemia may be caused by increased insulin production. Nesidioblastosis is one cause of persistent hyperinsulinism of the newborn. This case study reviews fetal physiology, neonatal presentation, and treatment.  相似文献   
155.
Spiral computer tomography (SCT) is a new method of computer tomography by which, in contrast to conventional CT, the information about absorptional capacity of tissues is obtained without omission of images which makes it possible to build MPR and 3D of a very high quality. 205 patients with diseases of hepatopancreatoduodenal area were examined, in 189 patients the diagnosis being verified. Optimal technique of intravenous bolus contrasting in SCT was developed. Using various time interval between the start of the scanning and the beginning of infusion of contrast media, it is possible to obtain primary image of the arteries (arterial phase of contrasting, time of delay 18-25 sec.), the picture of veins and the image of saturation of hepatic parenchyma--(venous return phase, time of delay 60-80 sec.), to reveal characteristics of contrasting of the liver masses during delay (8-15 min) phase. The largest quantity of masses are revealed in arterial phase of contrasting. Specific features of contrasting in hemangiomas and malignant tumors of the liver has been revealed. Hemangiomas absorb contrast medium already at the early phase as hypercontrasted lacunas in an outlying areas, at a late phase they are hyperdenced in relation to hepatic parenchyma. Primary and metastatic tumors of the liver accumulate contrast medium in an early phase along the whole area and quickly lose contrast medium during parenchymal phase. The method of contrast intensification enables evaluation of interrelation between tumor and vessels, to determine passage of hepatic arteries and branches of portal and hepatic veins, to visualise choledochal duct, to determine the distance between hepatic and tumor surface, and to produce these data as a view of multiplanar and three-dimensional image (reconstruction). The effectiveness of obtained reconstructions in planning of the extent of surgical intervention is demonstrated.  相似文献   
156.
The examined groups included 175 children whose fathers were alcoholics and 73 individuals from nonalcoholic parents. The study group was divided by age into children from infantile age to 15 years and 16-28-year-olds. The wide range of psychopathologic disorders were revealed in children up to 15 years of age: syndrome of hyperactivity, neurotic disturbances, mental retardation, epileptic-like syndrome. Alcoholism was found in sons only (3.77%). Mental disorders were revealed significantly more frequently in sons of alcoholic fathers than in their daughters. Their incidence increased with the age of the sons. The disturbances occurred significantly more frequently in the test group as compared with the control one (19 and 6.38%, respective by). In the older group (16-28-year-olds) the spectrum of mental disorders consisted of alcoholism, mental retardation, psychopathic-like and neurotic disorders. Alcoholism occurred most frequent and its rate depended on the age and sex. Frequency of alcoholism was 66.7% in sons aged 21-28 years and 15.38% in daughters of the same age. The conclusion was made about multiple risk for children of alcoholic fathers. More vulnerable contingent was the sons for which the risk of alcoholism was very high.  相似文献   
157.
Chromatin structure of nuclei of histogenetically distinct cells of humans and animals under normal and pathological courses of gestation was studied by the method of optic-structural computer analysis. A constant ratio of compact and diffuse chromatin is detected in nuclei of cells originating from all the germ layers. This ratio can change to a variable degree in cases of pathological gestation.  相似文献   
158.
The synthesis of oligosaccharide-lipids thought to play a role in the attachment of carbohydrate to protein has been studied in incubations of slices from calf kidney, pancreas, thymus, and liver, as well as from hen oviduct. These compounds were characterized after radiolabeling of their saccharide moiety by incubation with [14C]glucose or [14C]mannose and a comparison was made with the oligosaccharide-lipid produced by thyroid slices. Furthermore, the unlabeled glycolipid was prepared from hen oviduct for the purpose of quantitating its sugar constituents. Purification of the oligosaccharide-lipids extracted with chloroform/methanol/water (10/10/3) was achieved by DEAE-cellulose chromatography and their carbohydrate moieties were released by mild acid hydrolysis. On the basis of gel filtration it was determined that the lipid-bound oligosaccharides formed by oviduct, thymus, kidney, and liver had molecular weights comparable to that from thyroid (about 2400). The saccharide moiety of the glycolipid from pancreas was however distinctly smaller in size with a molecular weight of approximately 1800. Analyses of the radiolabeled oligosaccharide-lipids from oviduct, kidney, and thymus indicated that they, like the compound from thyroid slices, but unlike those believed to be formed by cell-free systems from various tissues, contained glucose in addition to mannose and N-acetylglucosamine as their monosaccharide constituents. This compositional data was supported by the finding that the unlabeled oligosaccharide from oviduct consists of 10 mannose, 1 glucose, and 2 N-acetylglucosamine residues. Sodium borohydride reduction of this oviduct saccharide moiety indicated that 1 of the 2 glucosamines was situated in a reducing terminal position. The radiolabeled oligosaccharide from the glycolipid produced by pancreas differed from the others analyzed in that it contained only trace amounts of glucose. Upon treatment with alpha-mannosidase this glucose-deficient pancreatic oligosaccharide was extensively digested (85% of the mannose released). In contrast, the carbohydrate moieties of oviduct, kidney, and thymus, like that of thyroid, underwent a more limited digestion with the alpha-mannosidase (55% or less of the mannose released) suggesting that the presence of glucose may serve to block a more complete degradation of these oligosaccharides by this enzyme.  相似文献   
159.
The roentgen appearance and pathogenesis of carpal instability are described in an evaluation of patients and cadavers with rheumatoid arthritis and calcium pyrophosphate deposition disease. Dorsiflexion (16%) and palmar flexion (8%) instability occurs in rheumatoid arthritis, particularly in patients with moderate to advanced disease. Navicular-lunate dissociation frequently accompanies dorsiflexion instability and results from involvement of the interosseous ligament between the two bones by rheumatoid pannus. Carpal instability and navicular-lunate dissociation also accompany pyrophosphate arthropathy, resulting from calcific deposition and cystic degeneration of ligamentous structures.  相似文献   
160.
The cutaneous recording of the gastric electrical activity according to the modified method of Sobakin was utilized. In fasting individuals changes in potential occured between 2 and 5 per min., in most of the cases after standard breakfast the frequency increased while lower amplitudes appeared. The frequency of electrical waves from the duodenum increased remarkably. It could be demonstrated that the peristalsis recorded by gastroscopy was synchronous with the electrogastrographic potentials. The applicability of the method for clinical diagnostic purposes is limited at the present time, because a "normal" electrogastrogram has not yet been established. Specific changes of the electrogastrogram have not been observed in various gastric diseases, which may be verified by routine diagnostic procedures.  相似文献   
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