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71.
72.
Divergence and convergence are both important elements of organizational design processes. This is often stated in the normative design literature, but it has hardly been studied empirically. How do designers of organizations diverge and converge in practice? Do they first develop alternatives and then choose the best one? Do they go through one or more successive cycles? And what makes them choose a certain route? In an in‐depth study of management consulting, we identified five different routes for diverging and converging in practice: one route for simple situations and four routes for complex situations. These routes differ in their sequence of activities, in their use of alternative solutions, and in their focus on content or on politics. It is shown that most design processes appear diamond‐shaped, with a divergent and a convergent side, but that these diamonds are often coloured or even fake, especially in socio‐politically complex situations. Pseudo‐divergence, i.e., the process of apparent divergence in public, is widespread.  相似文献   
73.
This study examined the incidence of infectious and neoplastic diseases among 222 HIV-seronegative gay men who participated in the Natural History of AIDS Psychosocial Study. Those who concealed the expression of their homosexual identity experienced a significantly higher incidence of cancer (odds ratio?=?3.18) and several infectious diseases (pneumonia, bronchitis, sinusitis, and tuberculosis, odds ratio?=?2.91) over a 5-year follow-up period. These effects could not be attributed to differences in age, ethnicity, socioeconomic status, repressive coping style, health-relevant behavioral patterns (e.g., drug use, exercise), anxiety, depression, or reporting biases (e.g., negative affectivity, social desirability). Results are interpreted in the context of previous data linking concealed homosexual identity to other physical health outcomes (e.g., HIV progression and psychosomatic symptomatology) and theories linking psychological inhibition to physical illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Modulation of the skin environment after stratum corneum (SC) perturbation has profound effects on the rate and effectiveness of barrier repair. Intermediate water exposure, e.g. moderate relative humidity, may provide the optimum water gradient for SC repair. More rapid recovery with semipermeable (SP) films in vivo was associated with increased hydration measured as moisture accumulation rate. We hypothesized that (i) damaged SC recovering under the high water exposure of full occlusion (FO) would have lower free amino acids (FAA) than sites with low hydration (no occlusion, NO) and semi‐occlusion (SP, semipermeable film, intermediate hydration) and (ii) SC under semi‐occlusion would have higher FAA than with low hydration. Volar forearm sites in 15 healthy adults were perturbed via cellophane tape stripping and treated with SP, FO and NO for five days. Barrier recovery rate, hydration, dryness and erythema were determined. Serial SC samples (n = 15) were collected on day 5 and FAA quantified using reverse‐phase HPLC and fluorescence detection. The cumulative protein removed was higher for SP than the control, NO and FO. FAA as total, individual amino acids and citrulline were consistently higher in the control than the three damaged sites. Generally, FAA was higher in NO than FO. Citrulline was higher for NO than SP and FO over the sampled SC. Levels were higher for SP than FO in certain, but not all of the FAAs. FAA was inversely correlated to barrier integrity. Skin hydration was relatively constant at the external microenvironment of the SP site, whereas the NO and FO had a reduction, i.e. a gradient, over the time. Overall, barrier recovery under conditions of a decreasing hydration gradient produced SC with higher levels of FAA than did conditions of full occlusion.  相似文献   
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A majority of performing arts organizations active in classical music, theatre, and contemporary dance rely on funding from “third parties” in order to organize productions in a recurrent manner. We adopt an entrepreneurial perspective to inform the debate on the economic sustainability of performing arts organizations: Is it a “deficit” in entrepreneurial orientation that condemns these organizations to financial dependence? Relying on a comparative case study design (n = 12), we distill a process model of performing arts entrepreneurship (PAE), which we compare with insights on innovative entrepreneurship. Our findings reveal that it is neither a lack of entrepreneurial dynamics nor the presence of opposing logics that creates dependence on multiple revenue streams. The introduction of a second revenue stream follows from adhering to artistic distinctiveness. Implications for practice and theory are elaborated.  相似文献   
78.
The biology of vernix caseosa   总被引:1,自引:0,他引:1  
The biology and physical properties of the uniquely human skin cream 'vernix caseosa' are discussed. This material coats the foetal skin surface during the last trimester of gestation and provides multiple beneficial functions for the foetus and newborn infant. Vernix has a complex structure similar to stratum corneum but lacks lipid lamellae and is more plastic due to the absence of desmosomal constraints. In utero, vernix is made in part by foetal sebaceous glands, interacts with pulmonary surfactant, detaches into the amniotic fluid, and is swallowed by the foetus. At the time of birth, vernix has a remarkably constant water content approximating 80%. Postnatally, vernix is simultaneously a cleanser, a moisturizer, an anti-infective, and an anti-oxidant. Vernix facilitates acid mantle development and supports normal bacterial colonization. Its hydrated cellular structure and unusual lipid composition provide a 'best' solution for the needs of the foetus and newborn, not least of which is the attraction of caregivers. Vernix is an important natural biomaterial of potential interest to cosmetic scientists, and other disciplines involved in product development and therapies targeting the complex interface between the stratum corneum and a changing terrestrial environment.  相似文献   
79.
A longitudinal study was conducted to assess to what extent intramammary infection (IMI) with non-aureus staphylococci (NAS) within the first 4 d after calving in dairy heifers affects quarter milk yield (qMY) and quarter milk somatic cell count (qSCC) during the first 4 mo of lactation. In total, 324 quarters from 82 Holstein Friesian heifers from 3 commercial dairy herds equipped with an automatic milking system were included and followed from calving up to 4 mo in lactation. The automatic milking system allowed us to precisely determine the daily qMY. A milk sample from each quarter was collected in early lactation (between 1 and 4 d in milk) for bacteriological culturing and measurement of the qSCC. Subsequently, milk samples were taken on a biweekly basis for measurement of the qSCC. The milk prolactin level in early lactation was measured, and the relation with NAS IMI was determined. Overall, NAS IMI in early lactation caused only a slight but significant increase in qSCC compared with milk from noninfected quarters during the first 4 mo in lactation, whereas no significant difference in daily qMY was present between NAS-infected and noninfected quarters. The milk prolactin level in early lactation did not differ between NAS-infected and noninfected quarters either. Our data suggest that IMI with NAS (as a group) present shortly after calving do not have an adverse effect on later production. The milk prolactin concentrations were not dissimilar between NAS-infected and noninfected quarters and thus cannot explain why NAS-infected quarters do not produce less than noninfected quarters.  相似文献   
80.
The aims of this study were to determine whether non-aureus staphylococci (NAS) are present in rectal feces of healthy dairy cows, and if so, to delineate species to which they belong and to study several phenotypic and genotypic traits as a first step toward determining the potential impact of fecal shedding of NAS on bovine udder health. Fecal samples were aseptically collected from the rectum of 25 randomly selected clinically healthy dairy cows in a commercial dairy herd using an automated milking system. Fecal NAS were isolated and then identified at the species level using transfer RNA-intergenic spacer PCR and sequencing of the 16S rRNA housekeeping gene. Strain typing was performed using random amplification of polymorphic DNA (RAPD)-PCR. The antimicrobial resistance profiles, biofilm formation, and growth and inhibitory characteristics of all NAS isolates were evaluated. Half of the cows were shedding NAS, resulting in 31 NAS isolates belonging to 11 different species. The most prevalent species were Staphylococcus rostri (23%, n = 7), Staphylococcus cohnii (16%, n = 5), and Staphylococcus haemolyticus (13%, n = 4) with all Staphylococcus agnetis, Staphylococcus chromogenes, and Staph. rostri isolates belonging to the same strain according to RAPD banding patterns. Acquired antimicrobial resistance was observed in 28 of the 31 NAS isolates, mainly due to β-lactamase production. Most of the isolates (84%, n = 27) had a weak biofilm-forming potential, but only 2 contained the bap gene. The ica and aap genes were not detected in any of the isolates. In vitro growth of Staphylococcus aureus and Streptococcus dysgalactiae was inhibited by Staph. agnetis isolates, and Staph. chromogenes isolates were able to inhibit the growth of Strep. dysgalactiae and Streptococcus uberis. All fecal isolates were able to grow when oxygen and iron were limitedly available, mimicking the growth conditions in the mammary gland.  相似文献   
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