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22.
SH Ahn DW Seo YK Ko DS Sung GU Bae JW Yoon SY Hong JW Han HW Lee 《Canadian Metallurgical Quarterly》1998,21(6):657-663
OBJECTIVE: To identify factors associated with the initiation of breast-feeding in a predominantly Puerto Rican population living in inner-city Hartford, Conn. DESIGN: Retrospective study of 144 Latino women (mean +/- standard deviation age = 26.3 +/- 5.7 years) with children at least 1 year old but younger than 6 years old (mean +/- standard deviation age = 3.0 +/- 1.2 years) at the time of the survey. Women were recruited from agencies sponsoring health programs for mothers and children. They were interviewed in their homes (69%) or at the Hispanic Health Council, Hartford, Conn (31%). SUBJECTS/SETTING: Low-income Latino women who had at least 1 preschooler at the time of the interview. The women lived in inner-city Hartford, and the overwhelming majority were Puerto Rican and received welfare assistance and food stamps. Seventy-eight percent of the women chose to be interviewed in Spanish; the other 22% were interviewed in English. STATISTICAL ANALYSES: Explanatory variables that related to breast-feeding initiation (P < or = .2) in bivariate chi 2 analyses were entered into a multivariate logistic regression model that was reduced using backward stepwise elimination procedures. RESULTS: Multivariate analyses indicated that breast-feeding the previous child, shorter length of maternal residence in the United States, not receiving prenatal bottle-feeding advice, more recent birth, and higher birth weight were positively associated with breast-feeding initiation. A major reason for choosing not to breast-feed was that women felt socially uncomfortable doing it. APPLICATIONS: Breast-feeding initiation was more likely in Latino women who received prenatal breast-feeding counselling and postpartum support. Mothers of low-birth-weight infants and women breast-feeding for the first time may need additional help. These findings can be used by programs like the Special Supplemental Nutrition Program for Women, Infants, and Children to increase breast-feeding initiation. 相似文献
23.
The current study examined the efficacy of graded doses of c9,t11 and t10,c12 CLA isomers on body composition, energy expenditure, hepatic and serum lipid liver biomarkers in hamsters. Animals (n = 105) were randomized to seven treatments (control, 1, 2, 3% of c9,t11; 1, 2, 3% of t10,c12) for 28 days. After 28 days treatment, 1–3% of t10,c12 lowered (p < 0.05) body fat mass compared to the control group. The 1–3% t10,c12 and 3% c9,t11 fed groups showed higher (p < 0.05) lean mass compared to other groups. We observed unfavorable changes in plasma total cholesterol and non-HDL cholesterol
levels in animals fed with 3% t10,c12 CLA isomers. The 2%, 3% t10,c12 groups presented elevated (p < 0.05) ALT levels. The present data suggest that a diet enriched with more than 2% t10, c12 led to liver malfunction and poses unfavorable changes on plasma lipid profiles. The 1% t10,c12 CLA lowered (p < 0.05) body fat mass and increased (p < 0.05) lean body mass. The c9,t11 CLA has less potent actions than t10,c12 CLA. We conclude that the actions of CLA on energy and lipid metabolism are form and dose dependent in the hamster model. 相似文献
24.
Recently, there has been increased interest in the geographical modelling of two or more diseases. In this article, we consider a number of issues relating to such an endeavour including the standardization process and the comparison of univariate and bivariate disease mapping models. A principle motivation for the examination of two or more diseases is to discover similarities or dissimilarities in the geographical distribution of risk. In this article, we propose a proportional mortality approach to give clues to areas of similarity and dissimilarity. A secondary aim of bivariate modelling is to 'borrow strength' between diseases in order to provide better estimates of risk in each area. We will illustrate various modelling strategies using incidence data from 1996 to 2000 on lung and bladder cancer in Washington state. 相似文献
25.
The sex pheromone released by the adult female Tenebrio molitor, 4-methyl-1-nonanol, is well known. In addition, there is evidence that adult males release a pheromone that attracts females.
The purpose of the present study was to isolate and identify male-released pheromone(s). Emissions from virgin adult males
and females were collected on filter paper and extracted with pentane. Extracts were analyzed by gas chromatography-mass spectrometry.
One male-specific compound was detected and identified as (Z)-3-dodecenyl acetate (Z3-12:Ac). In arena bioassays, E3-12:Ac was attractive to females only, at 1 and 10 μg doses. E3-12:Ac
was also attractive to females at a 10-μg dose. The presence of both male and female pheromones, each attracting the opposite
sex, may contribute to maintaining a high-density population of both sexes. 相似文献
26.
DS Reid K Kotte P Kilmartin M Young 《Journal of the science of food and agriculture》2003,83(10):1018-1021
Shelf‐life estimation for frozen foods can be a long process because of the long duration of shelf‐life at the lower temperatures of storage. A variety of rapid procedures have been proposed to suggest whether products will have acceptable shelf‐lives at low storage temperatures. These all have limitations. In this paper a new procedure is proposed which involves direct determination of shelf‐lives at the more elevated frozen storage temperatures, where change is more rapid. This is coupled with utilisation of information on the mobility temperature to establish a low‐temperature storage datum. A plot of expected shelf‐life as a function of temperature is produced using these two data sources. The effectiveness of the procedure is validated using existing literature data and newly generated data. The procedure allows for the effective estimation of the low‐temperature storage life of a product utilising data collected on the product in question. It requires around 60 days, while effectively estimating the storage temperatures required to achieve target shelf‐lives of 1 year, 18 months, 2 years or even longer. Copyright © 2003 Society of Chemical Industry 相似文献
27.
Tryptic digests of four polypeptides found in Kunjin virus-infected Vero cells, NV5, NV4, V3, and NV3, were compared by peptide mapping. The polypeptides to be analyzed were labeled with radioactive methionine and separated by electrophoresis through polyacrylamide gels containing sodium dodecyl sulfate. Because infection of Vero cells by Kunjin virus does not inhibit host cell protein synthesis, radioactively labeled viral polypeptides prepared from infected cells migrate coincidentally during sodium dodecyl sulfate-gel electrophoresis with some of the labeled host proteins. Thus, the genuine viral methionine-containing peptides in tryptic digests of viral proteins have been identified by co-analyzing polypeptides from [3H]methionine-labeled uninfected cells and [35S]methionine-labeled infected cells and determining the 35S/3H ratio in the peptides resolved in two dimensions on thin-layer chromatography plates. The peptide map of NV3 demonstrated that it is host coded, whereas NV5, NV4, and V3 have unique peptide maps and, therefore, account for approximately one-half of the coding potential of Kunjin virus RNA. 相似文献
28.
Sinus histiocytosis is a newly recognized benign disease affecting mainly children and young adults and usually having a protracted clinical course that is relatively unaffected by therapy. This paper describes four additional patients who had orbital involvement initially and reviews the salient clinical and histopathologic features of this entity. The outstanding clinical feature is cervical lymphadenopathy. Associated findings include low-grade fever, anemia, leukocytosis, and elevated IgG levels. A small percentage of patients develop proptosis with palpable orbital tumors. Such patients may not have appreciable lymphadenopathy. Progressive proptosis may lead to exposure keratitis, corneal ulceration, endophthalmitis, and loss of the eye. Histopathologically, the lymph nodes and orbital mass show a proliferation of large histiocytes intermixed with a variable proportion of lymphocytes and plasma cells. Lymphocytes and occasionally other cells derived from the hematopoietic system are commonly seen within the cytoplasm of the histiocytes. 相似文献
29.
30.
TL Raymond WE Connor DS Lin S Warner MM Fry SL Connor 《Canadian Metallurgical Quarterly》1977,60(6):1429-1437
To identify any metabolic effects of dietary fiber upon cholesterol metabolism in man, six adult volunteer subjects were fed eucaloric cholesterol-free formula diets, with and without added dietary fiber for two 4-wk periods. A large quantity of dietary fiber was fed, some 60 g of plant cell wall material (or 16 g of crude fiber) derived from corn, beans, bran, pectin, and purified cellulose. This provided about five times the fiber intake of the typical American diet. The addition of fiber to the cholesterol-free diet did not change either the plasma cholesterol level (171+/-21 mg/dl, SEM, to 167+/-18) or the triglyceride (103+/-39 to 93+/-27 mg/dl). The excretion of both endogenous neutral steroids and bile acids were unchanged with fiber (505+/-41 to 636+/-75 mg/day and 194+/-23 to 266+/-47 mg/day, respectively.) However, total fecal steroid excretion was increased 699+/-29 to 902+/-64 mg/day, P < 0.025). With fiber, intestinal transit time was decreased (59+/-9 to 35+/-8 h, P < 0.005), and both the wet and dry stool weights were greatly increased.A second group of six subjects was fed similar diets containing 1,000 mg cholesterol derived from egg yolk. The addition of fiber to the 1,000-mg cholesterol diet did not alter either plasma cholesterol level (233+/-26 to 223+/-36 mg/dl) or triglyceride (102+/-19 to 83+/-11 mg/dl). The excretion of endogenous neutral steroids (618+/-84 to 571+/-59 mg/day), of bile acids (423+/-122 to 401+/-89 mg/day), and of total fecal steroids (1,041+/-175 to 972+/-111 mg/day) were unchanged by fiber. The absorption of dietary cholesterol was not altered when fiber was added to the 1,000-mg cholesterol diet (44.0+/-3.3 to 42.9+/-2.5%). A two-way analysis of variance utilizing both groups of subjects indicated a significant (P < 0.001) effect of dietary cholesterol upon the plasma cholesterol concentration. We concluded that a large quantity of dietary fiber from diverse sources had little or no effect upon the plasma lipids and sterol balance in man in spite of the fact that intestinal transit time and stool bulk changed greatly. 相似文献