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1.
Klaus Reinhardt Hans Georg Breunig Aisada Uchugonova Karsten K?nig 《Journal of the Royal Society Interface》2015,12(110)
We explore the possibility of characterizing sperm cells without the need to stain them using spectral and fluorescence lifetime analyses after multi-photon excitation in an insect model. The autofluorescence emission spectrum of sperm of the common bedbug, Cimex lectularius, was consistent with the presence of flavins and NAD(P)H. The mean fluorescence lifetimes showed smaller variation in sperm extracted from the male (tau m, τm = 1.54–1.84 ns) than in that extracted from the female sperm storage organ (tau m, τm = 1.26–2.00 ns). The fluorescence lifetime histograms revealed four peaks. These peaks (0.18, 0.92, 2.50 and 3.80 ns) suggest the presence of NAD(P)H and flavins and show that sperm metabolism can be characterized using fluorescence lifetime imaging. The difference in fluorescence lifetime variation between the sexes is consistent with the notion that female animals alter the metabolism of sperm cells during storage. It is not consistent, however, with the idea that sperm metabolism represents a sexually selected character that provides females with information about the male genotype. 相似文献
2.
UE Reinhardt 《Canadian Metallurgical Quarterly》1994,13(4):22-24
The microflora of the large intestine in patients with odontogenic phlegmons of different localization were studied. 80.8% of such patients were found to have microecological disturbances, characterized by a decrease in the number of bacteria belonging to the genera Bifidobacterium, Lactobacillus, Enterococcus and Bacteroides and by an increase in the number of opportunistic microorganisms. 相似文献
3.
RA Reinhardt MP Masada GK Johnson LM DuBois GJ Seymour AC Allison 《Canadian Metallurgical Quarterly》1993,20(7):514-519
Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively. 相似文献
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Every general practitioner has to deal with urologic emergencies. The most frequent illnesses are urinary retention, acute scrotum, priapism, macrohematuria, nephritic colic, obstructive pyelonephritis and pyonephrosis. Whereas urinary retention, as well as acute ureteric stone colic must generally be treated by the practitioner, the urologist must often be consulted in case of an acute scrotum or for priapism. Testicular torsion is one situation, where surgical treatment needs to be performed within 6 hours. Of utmost importance is his timely assistance with the obstructive pyelonephritis and pyonephrosis. These are initially often not recognized, especially because the first ultrasound examination of the intrarenal pyelone may not show a dilatation of the collecting system despite obstruction. If the adequate treatment with drainage and antibiotics is applied too late, this can result in serious and potentially lethal consequences. 相似文献
6.
Otto Richter Thomas Schmidt Hand Büning-Pfaue und Dietrich Reinhardt 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1988,187(2):130-136
Zusammenfassung Es werden pharmakokinetische Modelle angegeben, um den Konzentrationsverlauf von Arzneimittelrückständen im Menschen zu berechnen, die mit der Nahrung aufgenommen werden. Dabei lassen sich zwei Kompartimentmodelle für die Kinetik in der Nahrung und im Menschen koppeln: Das erste System liefert die Anfangswerte (bzw. eine Folge von Anfangswerten) für das zweite System. Das Modell wird auf die Übertragung von Chloramphenicol durch Speisefische auf den Menschen und auf die Übertragung von Theophyin durch die Muttermilch auf gestillte Säuglinge angewendet. Durch Einführung einer günstigsten und ungünstigsten Parameterkombination werden Grenzverläufe für die Blutspiegel berechnet, die als Grundlage einer Rückstandsbewertung dienen können.
Residues of active substances following the consumption of contaminated food —Status report on the evaluation of residues based on two drugs
Summary Pharmacokinetic models are presented for the computation of time courses of blood levels of drugs in man following the consumption of contaminated food. Mathematically, two linear systems of differential equations are set up for the donor organism (e.g., trout) and for the recipient, (e.g., man), where the first system generates the initial conditions for the second. Models of this kind are applied to the transfer of chloramphenicol to man via carp and trout (which had previously been administered this drug) and to the transfer of theophylline to infants via breast milk. Limiting concentration profiles are computed by constructing the most favourable and most adverse combinations of parameters with respect to drug elimination in both the donor and recipient organism.相似文献
7.
UE Zappa 《Canadian Metallurgical Quarterly》1992,26(4):152-159
Scaling and root planing are the predominant and recognized forms of periodontal therapy. They have been known for centuries, and have been investigated with increasing intensity since the turn of the century. Scaling and root planing aim at therapeutic changes of the "hard tissue lesion" at the root surface, in order to render it biologically acceptable to cells capable of attaching to it. Two major components of these root surface alterations are calculus and cementum alterations. Numerous studies have shown that scaling and root planing effectively removes subgingival deposits, and that this removal is seldom complete in deeper pockets. Even though beneficial clinical effects of scaling and root planing have been shown, it is unlikely that the full potential of healing is utilized today due to technical shortcomings. Several studies have shown that the design and dimensions of curets as used today are not optimal. These instruments are for many situations too big, subject to rapid dulling, and produce a smear layer. Chemical agents have been used to remove this layer with limited success. The therapist is a virtually unknown factor in the system of delivering scaling and root planing. A recent study showed that scaling and root planing forces used by different therapists on similar root surfaces varied by factors greater than 10. In addition, higher forces were shown to remove significantly more root substance. Apparently there is a large subjective component included in the delivery of scaling and root planing therapy. Even though scaling and root planing have been shown to be effective therapeutic procedures, many aspects require more research. 相似文献
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9.
Within the scope of a parameter study the influence of the mixture composition of different self-compacting concretes on the
fresh concrete properties was investigated. For this purpose the standard test methods as well as the fresh concrete rheometer
“BTRHEOM” were used. The concrete was modelled as a two-phase system, consisting of the fluid phase paste and the solid phase
aggregates. The consistency control parameters paste volume, mortar volume and the coarse aggregate volume could be transferred
into the model parameter thickness of excess paste. By means of this model parameter the characteristic values of the standard
test methods like slump flow test and V-funnel test as well as the fundamental rheological parameters yield stress and the
plastic viscosity could be described. A comparative study showed that the yield stress and the plastic viscosity of self-compacting
concrete can be estimated based on the characteristic values of the slump flow test. 相似文献
10.