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Complaints of chronic fatigue as well as sleep disturbances are prevalent in Lyme disease. We compared polysomnographic measures of sleep in patients with documented Lyme disease with those of a group of age-matched normal control subjects. Eleven patients meeting Centers for Disease Control criteria for late Lyme disease with serologic confirmation by enzyme-linked immunosorbent assay and Western blot without a history of other medical or psychiatric illness and 10 age-matched control subjects were studied. Lyme disease patients and controls underwent 2 nights of polysomnography. Multiple sleep latency testing (MSLT) was performed in the patients. Sleep was staged by standard criteria, and continuity of sleep was assessed for each stage of frequency analysis of consecutive epochs. All patients studied reported sleep-related complaints, including difficulty initiating sleep (27%), frequent nocturnal awakenings (27%), excessive daytime somnolence (73%) and restless legs/nocturnal leg jerking (9%). Greater sleep latency, decreased sleep efficiency and a greater arousal index were noted in Lyme patients. The median length of uninterrupted occurrences of stage 2 and stage 4 non-rapid eye movement (NREM) sleep was less in Lyme patients (6.3 +/- 3.0 epochs in patients vs. 11.4 +/- 4.4 epochs in controls for stage 2, p < 0.01, and 4.3 +/- 4.4 epochs in patients vs. 11.2 +/- 6.3 epochs in controls for stage 4, p < 0.01), indicating greater sleep fragmentation. Mean sleep onset latency during the MSLT was normal (12.7 +/- 5.6 minutes). Three patients demonstrated alpha-wave intrusion into NREM sleep. These sleep abnormalities may contribute to the fatigue and sleep complaints common in this disease.  相似文献   
3.
Cr- and Mn-doped InN films were successfully grown by plasma-assisted molecular beam epitaxy on c-plane sapphire substrates. Low temperature GaN buffer layers grown by metal-organic vapor-phase epitaxy were used to accommodate the large lattice mismatch between InN and sapphire. A high n-type carrier concentration of 1.5×1020 cm–3 was measured in InN films with 3% Cr-doping. Films of this type exhibit a well-defined in-plane magnetic hysteresis loop and remanence for temperatures varying from 5 to 300K. The Mn-doped films, however, turned out to exhibit less clear magnetic properties. Thus, ferromagnetism in Cr-doped InN can be concluded from our measurements.  相似文献   
4.
Dieser Beitrag behandlt die Rolle des statistischen Ansatzes in der maschinellen (oder automatischen) Sprachverarbeitung.   相似文献   
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Zusammenfassung Es wird die Hypothese diskutiert, daß eine Verbindung zur Erzielung einer aromaintensivierenden Wirkung 2 negative Ladungen tragen muß, die 3–9, bevorzugt 4–6 C-Atome voneinander entfernt sind. Anstelle eines C-Atoms kann auch ein S-Atom treten. Eine evtl. vorhandene -Aminogruppe wirkt intensivierend, wenn siel-Konfiguration hat.
Flavour enhancing effect ofl-glutamate and similar compounds
Summary The hypothesis is discussed that for attaining a flavour enhancing effect a compound should carry 2 negative charges in a distance of 3–9, preferentially 4–6 C-atoms from each other. In place of a C-atom there may also be an S-atom. An -amino group possibly present will act intensifying if it showsl-configuration.
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7.
Zusammenfassung Es wind eine neue Methode beschrieben, die es gestattet, anhand der Aminosäurezusammensetzung eines Peptides vorauszusagen, ob theses bitter ist. Dazu wird aus Energie-Daten für die relativen Löslichkeiten der einzelnen Aminosäuren ein WertQ errechnet. Peptide mitQ < 1300 sind nicht bitter. Peptide mitQ > 1400 haben einen bitteren Geschmack. Alle bisher beschriebenen synthetischen Peptide mit definiertem Geschmack (Di- bis Eicosapeptide, 21 selbst synthetisiert, 37 aus der Literatur) entsprechen unserer Regel. Auch 8 in der Literatur beschriebene Oligopeptide aus Spinat mit bekannter Aminosdurezusammensetzung passen in die Regel.
Prediction of bitterness of peptides from their amino acid composition
Summary A method is described permitting to predict whether a peptide is bitter or not. The method is based on the amino composition, whereby a valueQ is calculated from the solubility data of the individual amino acids. Peptides withQ < 1300 are not bitter, peptides withQ > 1400 show a bitter taste.All synthetic peptides with defined taste described so far (di- to eicosapeptides, 21 synthesised ourselves, 37 from the literature) do comply with our rule. Eight oligopeptides from spinach with known amino acid composition described in the literature fit also in this scheme.
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8.
A theoretical approach for the interpretation of the kinetics of simultaneous stable and metastable phase precipitation in a binary system is proposed. The model, based on the nucleation and growth theory, defines a critical size different for each phase. The size of the clusters evolves by adding or substracting a single atom one at a time. A set of coupled differential equations is obtained for the chemical rate whose solution reproduces the kinetics of thermoelectric power measurements in the Fe-C multiphase system. Suppositions about the growing and dissolution rate constants reduce the size of the equation system with a gain in computation time.  相似文献   
9.
BACKGROUND: The emergence of psychogenic seizures after surgery for epilepsy is not well recognized. OBJECTIVES: To identify the frequency of psychogenic seizures in an 11-year surgical experience and to characterize the patients with this complication. METHODS: Ninety-six patients underwent surgery for epilepsy between 1985 and 1996. The surgical database was reviewed and all patients who experienced postoperative psychogenic seizures were identified. Patients were characterized by sex, age, psychopathologic conditions, full-scale IQ, duration of epilepsy, surgical procedure, and operative complications. Patients were compared with the surgical group as a whole for these variables. SETTING: A comprehensive epilepsy center. RESULTS: Five patients were identified: 3 men and 2 women. Mean full-scale IQ was 73 (range, 66-82). Mean age was 29.8 years (range, 22-36 years). Three patients were diagnosed as having psychosis, 1 with borderline personality disorder and 1 with generalized anxiety. Operations included 4 anterior temporal lobectomies and 1 occipital lobectomy. Two patients experienced operative complications. Compared with the surgical cohort, patients had a higher frequency of preoperative psychopathologic conditions, lower mean full-scale IQ, and a greater occurrence of operative complications. CONCLUSIONS: (1) Patients can develop new-onset psychogenic seizures after surgery for epilepsy. (2) Low full-scale IQ, serious preoperative psychopathologic conditions, and major surgical complications may be risk factors. (3) Atypical postoperative seizures should be evaluated with video electroencephalographic monitoring before concluding that they are epileptic.  相似文献   
10.
On the estimation of `small' probabilities by leaving-one-out   总被引:1,自引:0,他引:1  
We apply the leaving-one-out concept to the estimation of `small' probabilities, i.e., the case where the number of training samples is much smaller than the number of possible classes. After deriving the Turing-Good formula in this framework, we introduce several specific models in order to avoid the problems of the original Turing-Good formula. These models are the constrained model, the absolute discounting model and the linear discounting model. These models are then applied to the problem of bigram-based stochastic language modeling. Experimental results are presented for a German and an English corpus  相似文献   
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