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排序方式: 共有999条查询结果,搜索用时 15 毫秒
61.
K Sangthongpitag KR Moore NM Lapsys F Bao SR Babu PR Fain CF Verge 《Canadian Metallurgical Quarterly》1998,48(6):343-345
Abstract DNA typing of four tetrameric repeat loci (HUMVWA, HUMTH0I, D21SII and HPRT) was carried out in a Chinese Han population from Shanghai (East China) and one from Guangzhou (South-East China) using a quadruplex PCR amplification and detection of the fluorescent-labeled alleles on the ALF DNA sequencer. All loci were in accordance with Hardy-Weinberg equilibrium except for D21S11 in the Guangzhou population. A test for population differentiation showed no statistical difference in the allele frequency distribution between the two populations. Comparison of the allele frequency data with other Chinese Han populations from North and South-West China for the STR loci HUMVWA and HUMTH01 revealed heterogeneity between Northern Chinese Han and Southern Chinese Han, which is in accordance with previous studies on the basis of protein markers. 相似文献
62.
BACKGROUND/AIMS: Colorectal cancer incidence is higher in developed countries. High fat intake is one of the risk factors. However, many studies observed lower cholesterol serum levels on diagnosis of colorectal cancer. The aim of this assay was to study the serum cholesterol levels in patients with colorectal cancer and compare these values with individuals of the same age and sex. METHODOLOGY: Cholesterol serum levels of 85 patients with colorectal cancer were determined. Each of the patients with colorectal cancer were matched with an individual without cancer of the same age and sex. Total cholesterol concentrations were determined using an enzymatic colorimetric method. RESULTS: The mean serum of cholesterol was 183.4 for the colorectal group and 209.7 for the control group. This difference was statistically significant. This difference was more evident in patients with colon cancer and older than 60 years of age. There was no difference between the different Dukes' stage. CONCLUSIONS: Our study suggest an association between low blood cholesterol and colorectal cancer. We believe that the lower level of cholesterol observed in these patients is a consequence between the difference of colorectal carcinogenesis. 相似文献
63.
PE Leonards S Broekhuizen P de Voogt NM Van Straalen UA Brinkman WP Cofino B van Hattum 《Canadian Metallurgical Quarterly》1998,35(4):654-665
Bioaccumulation of non-, mono-, and di-ortho-substituted chlorobiphenyls (CBs) was investigated in four species of mustelids (weasel, stoat, polecat, and otter) and their preys, from a restricted area in the northern part of The Netherlands. Diets of these mustelids ranged from terrestrial (weasel, stoat, and polecat) to aquatic (otter). Diet-specific biomagnification factors (BMFs), CB in diet relative to CB in mustelids, were calculated for the sum of 28 congeners (SigmaCB), for the sum of the toxic equivalent concentration (SigmaTEQ) and on an individual congener basis. Biotransformation was studied in relation to structural CB properties (vicinal H-atom substitution). In addition, the methylsulphonyl CB-metabolites were determined. The concentration of SigmaCB on lipid weight basis increased in the order weasel < stoat < polecat < otter. On the basis of SigmaTEQ, the order changed to weasel < polecat < stoat < otter. Most of the differences in BMFs between the CBs could be explained by the vicinal H-atom structure-activity rules. For all mustelids, the lowest BMFs were found for congeners with vicinal H-atoms in the meta, para position. Indications were found that all mustelid species can metabolize these congeners. For some of the CBs, their methylsulphonyl-CB metabolites were determined and found to be present in concentrations up to 350-fold higher than those of the parent compounds. In addition, the non-ortho CBs 126 and 169 are selectively retained in the liver of weasel, stoat, and otter. These CBs had the highest BMFs of all congeners. However, rather surprisingly, in polecat the highest BMFs were found for di-ortho-substituted CBs. This animal was able to metabolize all congeners with vicinal H-atoms in the ortho and meta position (non- and mono-ortho CBs). The information concerning the differences in bioaccumulation of CBs for closely related mustelid species increased the understanding of reported differences in PCB toxicity between mink and ferrets, and suggest that weasel, stoat, and otter are at least as sensitive to CBs as are mink, while polecats are less sensitive. As otter is exposed to much higher concentrations of CBs trough their diet than weasel and stoat, the toxic threat of CBs will be the greatest for this animal. 相似文献
64.
AL Zietman WU Shipley DS Kaufman EM Zehr NM Heney AF Althausen FJ McGovern 《Canadian Metallurgical Quarterly》1998,160(5):1673-1677
PURPOSE: We describe a protocol designed to evaluate the use of twice daily radiation used together with cisplatin and 5 fluorouracil (5-FU) in the treatment of operable transitional cell carcinoma of the bladder with potential bladder preservation. MATERIALS AND METHODS: A total of 18 consecutive patients with T2-T4a bladder tumors underwent as complete a transurethral resection as possible, which was visibly complete in 14 cases. They then received twice daily radiation and infusion cisplatin and 5-FU during an induction phase. No therapy was given for 3 weeks, following which patients were reevaluated cystoscopically. Cases of clinical complete response by biopsy and cytology were consolidated with further chemotherapy/radiation using the same chemotherapeutic agents and radiation schedule. Patients who had incomplete responses were advised to undergo an immediate radical cystectomy. Of the 18 patients 15 subsequently received 3 cycles of adjuvant chemotherapy, consisting of methotrexate, cisplatin and vinblastine. Median followup for the entire group is 32 months. RESULTS: Of the 18 patients 14 had no detectable tumor after induction therapy. Of the 4 patients with persistent tumor 2 underwent radical cystectomy and 2 refused cystectomy, 1 of whom was treated with partial cystectomy and the other with consolidation chemotherapy/radiation. The actuarial overall survival at 3 years was 83%. The chance of a patient being alive at 3 years with a native bladder was 78%. No patient required cystectomy for hematuria or bladder shrinkage. Three patients in whom superficial tumors developed were treated successfully with bacillus Calmette-Guerin. Small bowel obstruction in 1 case was corrected surgically. CONCLUSIONS: This pilot study demonstrates a high rate of response to this combined chemotherapy/radiation regimen in conjunction with a visibly complete transurethral resection. Reevaluation after a short induction phase allows for the early selection of patients with persistent disease for radical cystectomy. 相似文献
65.
SF Stamatelopoulos NS Saridakis AK Chatzis AT Kalandaridou NM Desses A Lymperidis NM Giannopoulos SD Moulopoulos 《Canadian Metallurgical Quarterly》1998,22(11):993-997
This study examines whether a catheter mounted left intraventricular balloon may prevent left ventricular (LV) dysfunction following acute experimental myocardial infarction. In 10 anesthetized pigs, multiple coronary arterial ligations were applied around the apex of the heart. LV end-diastolic pressure (LVEDP), aortic flow (AF), and LV long and short axis fractional shortening (FS) were measured before and at 15 min intervals after ligations. At the 60th min after ligation, the LV long axis FS and AF decreased by 7.2 +/- 2.6% (p < 0.05) and 13.25 +/- 2.68% (p < 0.01), respectively, and the LVEDP increased by 4.3 +/- 1.1 mm Hg (p < 0.01) while no change was noted in the LV short axis FS. An intraventricular catheter mounted nonpulsating balloon was positioned over the endocardium of the infarcted area at the LV apex. Inflation of the nonpulsating balloon to an optimal volume, which was found to be equal to 8-10% of the LV end-diastolic volume, resulted in a reduction (by 3.8 +/- 1.2 mm Hg, p < 0.01) of the already increased LVEDP and in an increase (by 6.6 +/- 2.1%, p < 0.05) in the LV short axis FS while no statistically significant change was noted in the AF and LV long axis FS. It is concluded that an intraventricular catheter mounted balloon patch positioned over the endocardium of the infarcted area may ameliorate early LV dysfunction, possibly by interfering with the functional geometry of the LV contraction. 相似文献
66.
67.
MG Astapenko W Otto TM Trofimowa H H?ntzschel B Tautenhahn D Reinelt H Treutler AI Speranskij NM Mylow WA Duljapin TA Tarasenkowa 《Canadian Metallurgical Quarterly》1976,31(16):641-646
On the basis of own observations of courses the author adopts a definite attitude to the early symptomatology of the rheumatoid arthritis. During the first weeks of the rheumatoid arthritis the following symptoms are found: articular syndromes, more frequently in form of obstinate polyarthralgias, mono-oligoarthritis, accompanied by morning rigidity and accelerated BSR as well as impairment of the general condition. In the majority of the patients only the tentative diagnosis rheumatoid arthritis may be made. After a one to three months' course of the disease the diagnosis becomes more probable. It is above all based on constancy and symmetry, characteristic localisation of the articular process, morning rigidity, radiologically paraarticular loosening of the structure and morphological symptoms of an acute and subacute synovialitis. 6 to 12 months after the beginning of the disease a clinical picture forms which allows to make the diagnosis of a certain or classical rheumatoid arthritis in accordance with the criteria of the ARA. The occurrence of a high activity of multiple affection of the joints (permanent symmetrical polyarthritis including the small joints of the hands and feet), distinctive morning rigidity, high fever and much accelerated BSR, beginning with the first weeks of the disease, speaks for the possibility of the development of an arthrovisceral form of the course of rheumatoid arthritis. 相似文献
68.
1. The use of Li pre-treatment in rats before high pressure oxygen exposure has been reported effective in controlling convulsions. This is an effect which is better demonstrated if exposure to oxygen follows shortly after Li injection than exposure following several hours later. 2. This study has investigated the hypothesis that the protective action of Li may be exerted, in the short term, by its removing ammonia from the blood and alleviating the latter's known toxic action. 3. A normal Li distribution time profile in unstressed rat brain and blood following intraperitoneal injection has been established. Brain and blood ammonia, amino acids and Li concentrations were also measured in Li-treated animals exposed and convulsed by oxygen. These measurements were made both shortly (15 min) and also several hours after (24 hr) Li treatment. Ammonia and amino acid values in Li-protected groups were compared to normal unstressed animal values and also to values in animals convulsed by oxygen unprotected by Li pre-treatment. 4. In rat brain abd blood significant (P less than 0-001) elevation of ammonia and glutamine and depression of gamma-amino butyric acid (brain only) and glutamate was noted following oxygen treatment in unprotected animals. Prior injection of Li 15 min before high pressure oxygen exposure delayed convulsions twice as long. Additionally if these animals were only exposed to oxygen for a period of time equal to that which would normally produce convulsions in unprotected animals, brain and blood ammonia and amino acids were maintained near to unstressed animal levels. Concomitantly, blood Li concentrations were considerably depressed below the values one would expect from the previously determined Li distribution time profile. 5. In rats exposed to high pressure oxygen 24 hr after Li treatment there was no protective action against high pressure oxygen convulsion, rather a potentiating effect for convulsion was seen. 6. These data present compelling evidence for the controlling effect of Li in rats, on rising blood ammonia concentration which occurs in high pressure oxygen exposure. The effect might well be due to the known chelating properties of Li with ammonia. 相似文献
69.
An epidemiologic case-control study to ascertain the determinants of low birthweight was carried out in Santiago, Chile, from January to December 1989. The cases were defined as livebirths < 2500 g. The controls were livebirths > or = 2500 g of birthweight. All cases and a random sample (1:1) of controls were selected among 8,254 singleton births occurring at the El Salvador Hospital in the Eastern area of Santiago. These deliveries represented 50% of institutional deliveries in the area. Home deliveries (2%) and private hospital deliveries were not included in the study. Information was obtained from hospital medical records by six trained medical students. Some information could not be obtained from the hospital medical records. Thus the second step in data collection was the tracking of all the selected subjects to their referring neighborhood health centers. For the analysis, the data were divided into 3 case (outcome) categories: 453 subjects were the total case group. From these, 153 were the IUGR case group and 300 were the LBW preterm case group. The general control group consisted of 605 normal birthweight infants. 565 were the IUGR control group and 40 were the preterm control group. A total of 25 risk factors showed a significant crude odds ratio for at least one of the groups. In the multivariate logistic regression analysis eight variables: No. of pregnancies, previous adverse outcomes, previous LBW, pregnancy maternal weight, No. of visits, month of first prenatal care visit, maternal smoking and intrahepatic cholestasis of pregnancy, were significantly associated with LBW after adjustment by confounding. Eight risk factors: IUGR in previous pregnancies, Previous adverse outcome, Maternal smoking, intrahepatic cholestasis, maternal pregnancy weight, maternal height, month first prenatal visit, No. of visit, were significant to IUGR. Only two variables: pregnancy weight, divorced mother, were significantly associated with low birth weight in the preterm group. The most relevant risk factors were included in stepwise logistic regression models carried out for the outcome LBW for the general group, term group and preterm group, in order to adjust by confounding. Adjusted odds ratios were then obtained. Prenatal care related factors and maternal adverse obstetric factors were at higher significance for LBW in the general and IUGR groups. Only nutritional factors were related to LBW in preterm group. Women who delivered a LBW or IUGR infant were more likely to have fewer pregnancies, a history of previous LBW, lower prepregnancy weight and lower gestational weight gain. ICP was associated with an elevated risk of LBW that was independent of gestational age. 相似文献
70.