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141.
Plasma interleukin-1 beta (Il-1 beta) interleukin-6 (Il-6) and tumor necrosis factor-alpha (TNF-alpha) concentrations were measured in 26 women with Anorexia Nervosa (AN), nine of the restricted type (AN-R) and 17 of the binge-eating/purging type (AN-BP), in 24 women with Bulimia Nervosa (BN) and in 26 healthy age- and sex-matched controls. Concentrations of the cytokines were measured at the beginning of the study before starting any treatment and then after 1 and 3 months of combined cognitive-behavioral and pharmacological therapy (fluoxetine for AN-R and AN-BP, amineptine for AN-BP and BN, and fluvoxamine for BN). Basal values of Il-1 beta, Il-6 and TNF-alpha, were the same in patients and controls and did not change during treatments, in spite of the improvement of the mental disorders. This seems to exclude the possibility that alterations of basal plasma cytokine secretion are involved in the etiopathogenesis of AN and BN.  相似文献   
142.
OBJECTIVE: To characterize relationships among blood pressure, pulse rate, vitamin C status and other protective and risk factors for older British people, from a national survey. DESIGN: A cross-sectional analysis of survey data. SETTING: A population study, representative of mainland Britain. SUBJECTS: Among 914 people of both sexes living in the community, 373 were taking blood-pressure-lowering drugs and were therefore excluded from the analyses. INTERVENTIONS: Completion of an interview on health, lifestyle and dietary habits, recording of a 4-day dietary record, anthropometry and taking of a blood sample to determine haematological and biochemical status. MAIN OUTCOME MEASURES: Systolic and diastolic blood pressures, pulse rate, indices of micronutrient status including plasma ascorbate concentration, nutrient intake and haematology. RESULTS: Plasma ascorbate concentration was inversely correlated to systolic and diastolic blood pressures and pulse rate. Other covariates of blood pressure included age, sex, domicile, plasma retinol, fibrinogen and gamma-tocopherol concentrations, erythrocyte count, prothrombin time and urine sodium: creatinine ratio. Covariates of pulse rate included sex, domicile, plasma fibrinogen and platelet count. Blood pressure was also correlated to intake of vitamin C. CONCLUSIONS: Plasma ascorbate concentration and intake of vitamin C are covariates of blood pressure in older people living in Britain. New intervention studies are now needed, to test for possible causalities.  相似文献   
143.
144.
Galactorrhea as the result of hyperprolactinemia has been described in very rare cases associated to acute outbreaks of intermittent acute porphyria (IAP). In our country, any of such cases have been published or analytically documented. We present the case of a patient admitted in our hospital for the study of abdominal pain and galactorrhea, with latter diagnosis of IAP, supported by the assessment of the activity of the enzyme showing a deficit in the red blood cells.  相似文献   
145.
146.
The effects of insulin and platelet-derived growth factor (PDGF) on glycogen synthase activation were compared in 3T3-L1 fibroblasts and adipocytes. In the fibroblasts, PDGF elicited a stronger phosphorylation of mitogen-activated protein kinase (MAPK) and AKT than did insulin. Both agents caused a comparable stimulation of receptor autophosphorylation, MAPK, and phosphatidylinositol 3-kinase (PI3-K) activation in the adipocytes. However, adipogenesis resulted in the uncoupling of PI3-K activation by PDGF from subsequent AKT phosphorylation. The relative contributions of glycogen synthase kinase-3 (GSK-3) inactivation and protein phosphatase-1 (PP1) activation in the regulation of glycogen synthase in both cell types were evaluated. Insulin and PDGF caused a small increase in glycogen synthase a activity in the fibroblasts. Additionally, both agents caused a similar inhibition of GSK-3, while having no effect on PP1 activity. Following differentiation, insulin treatment resulted in a 5-fold stimulation of glycogen synthase, whereas PDGF was without effect. Both agents caused a comparable inhibition of GSK-3 activity in the adipocytes, whereas only insulin activated PP1. Finally, wortmannin completely blocked the stimulation of PP1 by insulin in 3T3-L1 adipocytes, indicating that PI3-K inhibition can impinge on PP1 activation. Cumulatively these results suggest that the weak activation of glycogen synthase in 3T3-L1 fibroblasts is mediated by GSK-3 inactivation, whereas in the more metabolically active adipocytes, the insulin-specific activation of glycogen synthase is mediated by PP1 activation.  相似文献   
147.
Oocytes from CBA mice varying in age from 2 to 11 months were cultured to the metaphase II stage of meiosis and the chromosomes analyzed. The oocytes from three maternal age groups were compared with respect to the mean number of oocytes obtained per mouse, the frequency of maturation to metaphase II, and the frequency of numerical chromosomes abnormalities. Both the mean number of oocytes obtained per mouse and the frequency of maturation decreased markedly with maternal age. The frequency of chromosome abnormalities in the oocytes increased with maternal age from the young to the middle-aged mice but dropped off in the oldest maternal age group. No hyperploid (n + 1) oocytes were observed in the young or old group of mice, but 5.2% hyperploidy occurred in the middle-aged group. It is suggested that the lack of hyperploid oocytes in the old CBA females might be due to a threshold effect in which oocytes that are damaged by the number of univalents present at metaphase I become atretic and do not progress to metaphase II. The frequency of diploid (2n) oocytes was 1.7% and was not maternal-age dependent.  相似文献   
148.
The effects of whole-plant corn silage (CS) particle size and long unprocessed grass hay (LH) supplementation on milk yield, chewing activity, and ruminal digestion in dairy cows were evaluated in 2 experiments. In Experiment 1, corn silage harvested at fine (6 mm; FCS) or coarse (23 mm; CCS) theoretical cut length were fed to 22 lactating Holstein cows. Treatments were 2 total mixed rations containing 58% of dry matter (DM) as FCS or CCS. Diet DM intake tended to be higher in cows fed FCS than those fed CCS (23.4 vs. 22.1 kg/d). However, milk yield and composition, body condition score, and plasma metabolite concentrations were not affected by the dietary treatments. In the second experiment, 5 cannulated Holstein cows were used in a 5 × 5 Latin square design to evaluate the effects of the addition of LH to the diets evaluated in Experiment 1 on chewing activity and ruminal digestion. Treatments were 5 total mixed rations: FCS-based diet plus the addition of 0, 5, or 10% LH (DM basis) and CCS-based diet plus 0 or 5% LH. Long hay addition linearly decreased DM intake in cows fed FCS-based diets (25.0 to 21.7 kg/d), but increased DM intake in those fed CCS-based diets (22.7 to 27.1 kg/d). The intake of neutral detergent fiber (NDF) increased with LH addition in CCS-based diets (7.6 vs. 9.4 kg/d). Rumination time increased (16.8 to 21.0 min/kg of DM intake) when LH was added to FCS-based diets, but it decreased when included in CCS-based diets (18.8 vs. 12.9 min/kg of DM intake). Ruminal pH was higher (5.9 vs. 5.7) and lag-time for in situ NDF disappearance was shorter (3.5 vs. 8.7 h) for cows fed CCS compared with cows fed FCS. The rate of NDF disappearance tended to be higher for the CCS-based diet with 5% LH than for the diet with 0% LH (2.0 vs. 4.4%/h), but solids passage rate was not affected by the treatments. These results suggest that addition of LH to FCS-based diets does not affect ruminal environment or digestion, but depressed DM intake. In contrast, addition of LH to CCS-based diets may improve ruminal NDF digestion, increasing DM intake by reducing filling effect and time needed for rumination.  相似文献   
149.
Feed production systems should consider more sustainable solutions to reduce the pressure on earth's finite resources. In this work, we investigated the effect of microencapsulated condensed tannins (MCTs)-enhanced diet on the cow milk characteristics. The diet reduced the urea content, while preserved and the n-3 and n-6 portion of fatty acids. Aside from the rising of vitamin C level, MCTs had a negative effect on the amount of B group vitamins. MCTs may be considered a promising feed supplement that offers a good trade-off in terms of milk chemical quality while increasing the environmental sustainability of cattle livestock.  相似文献   
150.
The inefficiency of protein utilisation by ruminants fed protein concentrates (based on legume meals) causes serious economic loss and environmental damage owing to their rapid hydrolysis and deamination in the rumen. Thus efforts aimed at slowing the ruminal fermentation of such feeds are needed, and recent studies have observed potentially positive effects of tannins on ruminant nutrition under certain circumstances. Tannins are a complex group of naturally occurring plant polyphenols characterised by their ability to bind with proteins. This property of tannins is considered responsible for the decreased ruminal digestibility of forages both in vivo and in vitro. Under that perspective, commercial tannic acid was added at three proportions (10, 25 and 50 g kg?1 on a dry matter basis) to four different legume meals (horse bean, kidney bean, soybean and pea), and the effect on in situ dry matter and crude protein ruminal disappearance was assessed. The results confirmed the dose‐dependent (although not persistent after 48 h) slowing of in situ digestibility, this effect being significant at the highest tannin treatment when compared with untreated samples. Scanning electron microscopy revealed that soybean seed endosperm cell walls were protected from digestion by the ruminal microbiota, while the digestion of starch granules was relatively unaffected by tannic acid. Electrophoresis of the protein fractions confirmed the lower digestibility of tannin‐treated seeds as well as the relative lack of alteration of the electrophoretic profile of individual proteins. Implications for the digestion of concentrates in ruminants are discussed. Copyright © 2004 Society of Chemical Industry  相似文献   
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