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1.
To study bone loss relationships to aging and menopause, cross-sectional bone mass measurements by digital image processing (DIP method), and menopause information collected by questionnaire, were analyzed on 291 women who live in Tsukude village. The results are as follows. 1) The mean DIP values (sigma GS/D, MCI) by age-stratified groups decrease with age after menopause. The rate of bone loss in sigma GS/D is almost constant, but in MCI it increases with aging. 2) In 30-year old and 40-year old age groups, the frequency distribution of DIP values is symmetrical and bell-shaped. But after the fifties the distribution is asymmetrical, with the mode of distribution deviated toward low bone mass. The change of mode with aging is larger than that of mean. This fact suggests that change of mean bone mass substantially underestimates actual bone loss from aging. 3) The change of the mean DIP values stratified by years elapsed since menopause is not especially large at start of menopause but becomes almost constant after menopause. DIP values reflect the bone loss from the aging rather than from menopause, and are beneficial to the study of bone loss in elderly women.  相似文献   
2.
The authors studied the distribution of lipoprotein(a) (Lp(a)) levels with stratification for age and sex, as well as the relation between Lp(a) and atherosclerotic risk factors in a large Japanese population between 1992 and 1993. The subjects were 1,235 males and 1,762 females over 30 years old. Lp(a) was measured by an enzyme-linked immunosorbent assay. Lp(a) levels were higher in females than in males. The increase in Lp(a) with age was statistically significant, and the proportion of subjects with Lp(a) levels > 30 mg/dl also increased with age. In the obese subjects (body mass index (BMI) (kg/m2) > 26), Lp(a) levels were lower than in the non-obese subjects (BMI < or = 26) (p < 0.01 in males; p < 0.05 in females). Male alcohol drinkers had lower Lp(a) levels than nondrinkers (p < 0.05). Age, low density lipoprotein subtracting Lp(a) cholesterol [Lp(a) x 0.3], and fibrinogen level were all positively correlated with Lp(a) in both sexes. Alcohol consumption (g/day) and triglycerides were inversely correlated with Lp(a) in males, while total cholesterol subtracting Lp(a) cholesterol [Lp(a) x 0.3], high density lipoprotein, and factor VII were positively correlated in females. Multiple logistic regression analysis showed that triglycerides in males and BMI and fibrinogen in females were significant independent variables. The authors conclude that Lp(a) level is affected by various factors, such as alcohol drinking, BMI, sex, and age, and is not only correlated with lipid levels but also with hemostatic factors such as fibrinogen and factor VII.  相似文献   
3.
4.
Lactic acid bacteria involved in the natural fermentation of both home-produced and commercial mawè were investigated during a 72 h fermentation period. Lactobacillus spp. constitute the majority (94%) of the strains of the lactic acid bacteria isolated, among which 89% represent the Betabacterium group. They include L. fermentum (biotype cellobiosus) (41%), L. fermentum or L. reuteri (19%), L. brevis (26%), L. confusus (less than 2%), L. curvatus (less than 1%) and L. buchneri (less than 1%). Other isolated lactic acid bacteria were L. salivarius, Lactococcus lactis, Pediococcus pentosaceus, Pediococcus acidilactici and Leuconostoc mesenteroides. Several species were detected at the early stage of fermentation, but the final stage was dominated by L. fermentum (biotype cellobiosus) and L. fermentum or L. reuteri totalling 90% of the isolated strains. The trend was the same for both home-produced and commercial mawè. No strains of L. plantarum, generally reported as dominating lactic acid bacteria at the final stage of fermentation of most plant foods, were isolated.  相似文献   
5.
Abstract: In this study, the behavior and enterotoxin production by 10 different coagulase negative Staphylococcus (CNS) strains inoculated in cooked ham, reconstituted skimmed milk, and confectionery cream in the presence or absence of background microbiota have been investigated. After inoculation (103 CFU/g), foods were incubated at 25, 30, and 37 °C and aerobic mesophilic and CNS counts were carried out at 12, 24, 48, and 72 h. Staphylococcal enterotoxins (SE) detection was performed by SET-RPLA (Oxoid, Basingstoke, U.K.) and mini-Vidas® (bioMérieux, La Balme les Grottes, France). CNS counts increased during incubation and approached 106 to 107 CFU/g after 12 h at 37 °C in the 3 foods studied. At 25 °C, counts reached 106 to 107 CFU/g only after 24 to 48 h. The interference of background microbiota on CNS behavior was only observed when they grew in sliced cooked ham, which presented a high initial total count (105 CFU/g). Significantly higher counts of CNS isolated from raw cow's milk in comparison with food handlers isolates were found in reconstituted milk and confectionery cream. Although CNS strains were able to produce SEA, SEB, and SED in culture media, in foods, in the presence or absence of background microbiota S. chromogenes LE0598 was the only strain able to produce SEs. Despite the scarcity of reports on CNS involvement with foodborne disease outbreaks, the results found here support the CNS growth and SE production in foods even in the presence of background microbiota and may affect food safety.  相似文献   
6.
Polypropylene composites were prepared by copolymerizing styrene and divinylbenzene in molten polypropylene by using an extruder. The resultant copolymers are of very fine particles uniformly dispersed in polypropylene phase with no aggregation. The properties of the resultant polypropylene composites were studied: crystalline structure, and mechanical, dynamic viscoelastic, and thermal properties. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1614–1620, 2000  相似文献   
7.
Recently, we revealed that the motion of the normal fluid component in the aerogel is well described by the frictional relaxation model (Higashitani et al. in Phys. Rev. B 71:134508, 2005). To clarify the origin of the friction between the quasiparitcles and the aerogel, we have performed the fourth sound resonance experiments at two different pressures. The fourth sound resonance experiment can derive both the static and the dynamic informations simultaneously, namely, the superfluid fraction and the energy loss. From the static part, we found that the superfluid fraction slightly changes with changing the pressure. We calculated the density of states in the impurity system by means of HSM and propose that the constituent of the normal fluid component is the quasiparticles at emerging levels in the energy gap, which we call the midgap states. From the dynamic part, we found that the energy loss depends on the pressure, in contrast to the superfluid fraction. The pressure dependence of the frictional relaxation time has been calculated, and we revealed that the response of the normal fluid component against the frictional force depends on the BCS coherence length.  相似文献   
8.
Detailed geochemical and geothermal studies have been carried out in the Red Sea and Gulf of Aden in order to understand the regional distribution of source rocks through time, and the effects of changing heat flow through time.
These studies have shown the presence of generally thin developments of fair to very good quality source rocks. Most of the identified source rocks occur in syn-rift sediments throughout the Red Sea area, but pre-rift source-rock occurrences have been identified in Yemen (Gulf of Aden). Somalia, and to a lesser extent in Egypt. Isolated occurrences of post-rift source rocks have also been identified. The data can be interpreted in the regional context of the sedimentary facies of the region in order to predict possible geographic distribution of source rocks.
Maturity gradients determined using vitrinite reflectivity and spore coloration range from low (often in post-rift sections) to high (often in syn- and pre-rift sections). The maturity gradients in many of the sections analysed show intersecting bi-linear trends, suggesting very high palaeogeothermal gradients in sediments close to the rifting centres. In such areas, the oil and gas "windows" are relatively shallow and thin. In areas where crustal thickening has reduced heat flux. hydrocarbon generation may have occurred in the past, but has since ceased.
The models derived during this project for source-rock distribution and heat-flow variations are consistent with the tectonic evolution of the basin, and show that there is good potential in parts of the study area for oil generation, accumulation and preservation in pre-rift, syn-rift as well as in post-rift sediments.  相似文献   
9.
Although cardiac rupture is the second most common cause of death after ventricular failure in acute myocardial infarction, no diagnosis has ever been made before an episode of clinical compromise, and no significant predictive factors have been described. This study was designed to determine whether high serum C-reactive protein (CRP) levels could predict the incidence of subacute cardiac rupture after acute myocardial infarction. Nine consecutive patients with cardiac rupture were compared retrospectively with 28 consecutive control patients without rupture after acute myocardial infarction. In the rupture group, peak serum CRP levels increased rapidly and markedly after infarction, reaching more than 20 mg/dl on day 2, and persisted at high levels compared with those in the control group. However, the time course and levels of serum creatine phosphokinase were not significantly different between the two groups. High serum CRP levels ( > 20 mg/dl) had a high diagnostic sensitivity (89%) and specificity (96%) for cardiac rupture. Patients with persistently high serum CRP levels, particularly above 20 mg/dl, might have high probability of occurrence of sub-acute cardiac rupture after acute myocardial infarction.  相似文献   
10.
The varicocele is benign pathology which sometimes involves disorders of testicular growth. Those can cause a hypofertility. We saw in a retrospective way the 243 patients having been treated by percutaneous embolisation from May 1985 to August 1993. At 150 patients being 1 year at least of postoperative retreat, 70% of cases present a cure, 15% of patients repeated and were taken again surgically. At 8% of patients, the embolisation was not technically possible for reasons of vascular anomalies or spasm of the vein during the procedure. The morbidity of this technique is low, this involves therefore a right choice of the treatment of the varicocele which does not prevent any surgical treatment in the event of repetition or in the event of technical failure.  相似文献   
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