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1.
EB Guglia 《Canadian Metallurgical Quarterly》1996,(10):34-36
The authors elaborated a method measuring air level of orthophosphorous and orthophosphoric acids by means of ion chromatography within the range of 0.1-25 mg/cu m. The samples are extracted through concentration on a filter. The analysis regime includes depression of the background levels. The separating column (4 x 200 mm) is filled with anion exchanger BT IAN, the suppressing column (6 x 150 mm) is filled with cation exchanger Dowex 50 x 8, the elutriating agent is 1.5 mM of sodium carbonate, the detector is conductometric. Minimal amounts of ions that could be detected in the analyzed solution are 7-10 ng (HPO32-), 10-15 ng (HPO 42-). The method is designed to analyze the air of workplace. 相似文献
2.
V. E. Gul O. A. Sdobnikova A. L. Peshehonova L. G. Samoilova O. A. Khanchech A. I. Suvorova 《Polymer Engineering and Science》1993,33(22):1489-1493
Reported is an attempt to attain orientation of macromolecules during extrusion of films of cellulose derivatives that led to the liquid-crystalline state of a polymer and resulted in enhanced film strength. 相似文献
3.
OBJECTIVE: To describe an immunocompromised patient (without AIDS) with nosocomial infectious diarrhea caused by Pseudomonas aeruginosa. Oral ciprofloxacin therapy proved to be effective. CASE SUMMARY: An 80-year-old woman with type II diabetes mellitus and hypertension developed progressive renal insufficiency, was hospitalized because of uremia, and underwent hemodialysis. When the patient developed hematochezia, Duke's C sigmoid colon cancer was detected and successfully resected. She received broad-spectrum antibiotics in the perioperative period. The patient then developed profuse diarrhea associated with abdominal cramping, a low-grade fever, prostration, and headache. The patient then started to received vancomycin 500 mg po qid empirically. Four days later, the diarrhea continued unabated, the Clostridium difficile titer was negative, and the vancomycin therapy was stopped. However, the stool culture was positive for heavy growth of P. aeruginosa sensitive to ciprofloxacin. The patient then began to receive ciprofloxacin 500 mg po bid. Within 3 days the diarrhea stopped. Oral ciprofloxacin therapy was continued for 10 days and the patient remained free of symptoms with formed stools thereafter. DISCUSSION: Diarrhea following the use of broad-spectrum antibiotics implicates pseudomembranous colitis as the cause. The patient did not respond to oral vancomycin therapy and had a negative stool assay for C. difficile toxin. This patient was believed to have Pseudomonas enteritis, which was confirmed by 2 positive stool cultures. The administration of oral ciprofloxacin therapy stopped her diarrhea with a rapid resolution of symptoms. CONCLUSIONS: P. aeruginosa as a cause of infectious diarrhea is unusual. When it occurs, it usually represents a nosocomial infection in an immunocompromised host. This report illustrates that oral ciprofloxacin therapy is effective for Pseudomonas enteritis, with rapid resolution of symptoms. 相似文献
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C Gnardellis A Trichopoulou K Katsouyanni E Polychronopoulos EB Rimm D Trichopoulos 《Canadian Metallurgical Quarterly》1995,6(1):74-77
The involvement of mental health professionals in determinations of dangerousness is both common and controversial. Among the various contexts for these evaluations, the release of potentially violent forensic patients from maximum security facilities evokes justified concern from involved experts and apprehension to outrage from the immediate community. We sought to examine how conclusions are reached on dangerousness at two sequential stages: clinical recommendations and Manifest Dangerousness Hearings decisions. In an archival study of 245 patients, we found that lack of progress in the institution and physical assaultiveness were the strongest correlates with dangerousness. In contrast, experts and review boards appeared to be relatively less influenced by diagnosis, types of treatment, and sociodemographic variables. 相似文献
7.
The present study examines the role of insulin, glucagon and cortisol in the regulation of gluconeogenesis from lactate and amino acids in fetal and newborn rats. Injection of glucagon in the full-term fetal rat caused a rise in glucose (and insulin) and a fall in blood levels of most individual amino acids, stimulated hepatic accumulation of 14C-amino isobutyric acid and 14C-cycloleucine and increased the conversion of 14C lactate, alanine and serine to glucose in vivo and in vitro (liver slices). Such changes were equivalent to the changes seen in 4 h old newborn rats. When glucagon was administered at birth, little difference was observed between control and treated animals in plasma amino acids and a smaller increment in conversion of 14C substrate to glucose occurred. By contrast, insulin injection at birth caused hypoglycemia, suppression of levels of certain amino acids and inhibition of conversion of 14C substrates into glucose. Glucose injection at birth caused elevated glycemia and plasma insulin and suppression of most amino acid levels and of conversion of 14C substrate into glucose. Cortisol injection at birth caused a marked, generalized by hyperaminoacidemia, a stimulation of glucagon secretion and of conversion of 14C substrates into glucose. These observations support the thesis that glucagon plays a major role in the induction of hepatic gluconeogenesis and that insulin acts as an antagonist hormone. 相似文献
8.
A family is described in which the mother and 2 of the 5 children had Felty's syndrome, a pattern of inheritance suggesting a dominant defect and one which has not previously been reported. The family is also of interest in that the other sib had rheumatoid arthritis. 相似文献
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ME Soberano EB Ong AJ Johnson M Levy G Schoellmann 《Canadian Metallurgical Quarterly》1976,445(3):763-773
Affinity chromatography on agmatine-Sepharose was used for the separation of two active forms of urokinase (EC 3.4.99.26) from partially purified human urinary urokinase. The approximate molecular weight of the heavier form was 47 000 and of the lighter 33 400. Both forms were homogeneous by sodium dodecyl sulfate gel electrophoresis and by 3H-labeled diisopropylphosphorofluoridate and 14C-labeled p-nitrophenyl-p'-guanidinobenzoate incorporation studies. The 33 400 mol. wt. form had a single chain, and the 47 000 mol. wt. form had two chains (33 100 and 18 600 mol. wt.) linked by disulfide bonds. The specific activity of the heavier form was 104 000 CTA units/mg protein, compared with 226 000 units/mg for the lighter form but the activities per mmol of active site (molar activities) of the two forms were almost identical (9.6-10(9) and 10.2-10(9) CTA units/mmol). Isoelectric focusing on gels showed that the 47 000 material contained one major subform with a pI of 8.60 and a minor subform with a pI of 8.90, while the 33 400 material had three major subforms with pI values of 8.35, 8.60 and 8.70, respectively, and a minor subform with a pI of 8.05. 3H-labeled diisopropylphosphorofluoridate incorporation studies revealed an active-site serine residue in the heavy chain. 相似文献