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1.
A BASIC program has been devised for the hydropathic analysisof protein sequences according to the method of Kyte and Doolittle(1982). The program uses sequence data from input files thatare created with a word processor and produces two types ofoutput file: one contains a bar graph of the hydropathic profilein a format that can be easily edited; the other is a tabulationof hydropathic indices along a protein's sequence that can beused as input by the program for the production of a bar graphor as input into other graphics and analysis software. An MS-DOSmicrocomputer, operating under IBM BASICA or GWBASIC and a dotmatrix printer with block graphics capabilities are the onlyhardware requirements for graphic display of hydropathy profiles.The program is capable of unattended analysis from a list ofup to 15 input files. ; accepted on March 10, 1986  相似文献   
2.
The red blood cells of normal adult ducks contain two main hemoglobins. The most abundant type, HbA, comprises approximately 80% of the total, with the remaining 20% being made up of HbD. An attempt was made to determine whether during hemolytic anemia a special alpha globin chain (alpha s) replaces the alpha chain of HbA found in normal animals. This special stress alpha globin, whose existence has been seriously questioned, was originally postulated to explain the sequence discrepancies obtained between alpha chains of normal and anemic chickens and ducks. Using gel electrophoresis, isoelectric focusing, and HPLC peptide mapping techniques no qualitative differences between the alpha A globins of normal and anemic animals were found. The nature of the beta globin chains present in adult ducks has also never been rigorously established. In this work, a variety of techniques, including HPLC, gel electrophoresis, and microcolumn amino acid analysis, were used to examine the beta chains from each hemoglobin. Using these methods, no differences were found between the beta globin chains of the two hemoglobins.  相似文献   
3.
Zusammenfassung In einem gegen die natürliche Langwellenstrahlung abgeschirmten Versuchsraum wurde die Atmung von Mäuselebergewebe in künstlich erzeugten elektromagnetischen Feldern gemessen. Unter der Einwirkung von zyklonale Wetterlagen simulierenden Programmen (30–100 pulses sec–1, > 100 mV m–1, 10–100 kHz) ergab sich im Vergleich zu den Kontroll-QO2-Werten eine signifikante Dämpfung der Gewebeatmung um 42% ± 2,8% (p<0,001). Die Applikation eines H-Feld-Programms blieb ohne Wirkung. Programme mit Simulierung antizyklonaler Wetterlagen(1–3 pulses sec–1, <10 mV m–1, 10 kHz) hatten ebenfalls keinen Einfluss auf die Atmungsgeschwindigkeit der Mäuseleber.
In a room completely shielded against long wave radiation, liver tissue of mice in a Warburg apparatus was exposed to artificial electromagnetic radiation simulating cyclonic and anticyclonic weather. Under the influence of simulated cyclonic weather programs (30–100 pulses sec–1, > 100 mV m–1 10–100 kHz) a significant decrease (42% ± 2,8%) of the respiration rate of the liver tissue was found, compared with the control QO2 (p < 0,001). The application of a cyclonic weather H-field program had no effect. Simulated anticyclonic weather (1–3 pulses sec–1, < 10 mV m–1, 10 kHz) also failed to produce a demonstrable effect on the respiration rate of mouse liver tissue.

Resume Dans un local absolument protégé contre l'irradiation naturelle par ondes longues, des tissus de foie de souris ont été exposés, dans un appareil de Warburg, à des impulsions électromagnétiques artificielles, correspondant à celles de temps cyclonal et anticyclonal. Sous l'influence des programmes artificiels simulant le temps cyclonal(30–100 pulses sec–1, > 100 mV m–1, 10–100 kHz), il a été constaté une inhibitation significative de la respiration tissulaire de 42% ± 2,8% comparée aux valeurs du QO2 de contrôle (p < 0.001). L'application d'un temps cyclonal-"H-field"-programme séparé, est demeuré sans effet. De même. les signaux de temps anticyclonal(1–3 pulses sec–1, < 10 mV m–1, 10 kHz), n'ont eu aucune influence démonstrable sur la vitesse de respiration du fois de souris.
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4.
The acyl-CoA ligases convert free fatty acids to acyl-CoA derivatives, and these enzymes have been shown to be present in mitochondria, peroxisomes, and endoplasmic reticulum. Because their activity is obligatory for fatty acid metabolism, it is important to identify their substrate specificities and subcellular distributions to further understand the cellular regulation of these pathways. To define the role of the enzymes and organelles involved in the metabolism of very long chain (VLC) fatty acids, we studied human genetic cell mutants impaired for the metabolism of these molecules. Fibroblast cell lines were derived from patients with X-linked adrenoleukodystrophy (X-ALD) and Zellweger's cerebro-hepato-renal syndrome (CHRS). While peroxisomes are present and morphologically normal in X-ALD, they are either greatly reduced in number or absent in CHRS. Palmitoyl-CoA ligase is known to be present in mitochondria, peroxisomes, and endoplasmic reticulum (microsomes). We found enzyme-dependent formation of lignoceroyl-CoA in these same organelles (specific activities were 0.32 +/- 0.12, 0.86 +/- 0.12, and 0.78 +/- 0.07 nmol/h per mg protein, respectively). However, lignoceroyl-CoA synthesis was inhibited by an antibody to palmitoyl-CoA ligase in isolated mitochondria while it was not inhibited in peroxisomes or endoplasmic reticulum (ER). This suggests that palmitoyl-CoA ligase and lignoceroyl-CoA are different enzymes and that mitochondria lack lignoceroyl-CoA ligase. This conclusion is further supported by data showing that oxidation of lignoceric acid was found almost exclusively in peroxisomes (0.17 nmol/h per mg protein) but was largely absent from mitochondria and the finding that monolayers of CHRS fibroblasts lacking peroxisomes showed a pronounced deficiency in lignoceric acid oxidation in situ (1.8% of control). In spite of the observation that lignoceroyl-CoA ligase activity is present on the cytoplasmic surface of ER, our data indicate that lignoceroyl-CoA synthesized by ER is not available for oxidation in mitochondria. This organelle plays no physiological role in the beta-oxidation of VLC fatty acids. Furthermore, the normal peroxisomal oxidation of lignoceroyl-CoA but deficient oxidation of lignoceric acid in X-ALD cells indicates that cellular VLC fatty acid oxidation is dependent on peroxisomal lignoceroyl-CoA ligase. These studies allow us to propose a model for the subcellular localization of various acyl-CoA ligases and to describe how these enzymes control cellular fatty acid metabolism.  相似文献   
5.
Two experiments were conducted to investigate the efficacy of a vaginal mucus impedance meter for the detection of estrus in the dairy cow. In Experiment 1 the positioning of the probe within the vaginal tract was examined in dairy cows (n=6) by measuring mucus impedance at 5-cm intervals during probe withdrawal and comparing these fixed distance measurements with the depth within the vaginal tract at which the lowest impedance measurement was recorded. Measurements at 15 and 20 cm from the vulva were significantly lower than at other fixed depths, but did not show a reduction during estrus. The lowest recording upon withdrawal of the probe, which usually occurred between 15 and 20 cm from the vulva, was significantly lower than at any fixed depth recordings and was reduced proportionate during estrus to 0.14 of its non-estrus value. In Experiment 2 the accuracy of the probe to confirm estrus in cows exhibiting possible estrus signs was examined. Dairy cows (n=191) were inseminated either on the basis of herdsman observation of behavior alone (Treatment A) or on the basis of herdsman observation with cows exhibiting signs of estrous behaviour, but not standing to be mounted, being tested for vaginal mucus impedance (Treatment B). There were no significant treatment differences in the estrus detection rate, conception rate or other reproductive performance parameters. However, in 12% of cows in Treatment B, measurement of vaginal mucus impedance detected an extra estrous event, giving a theoretical increase in the estrus detection rate from 0.67 to 0.74 detected/predicted estrous events. It was concluded that when using a vaginal probe the lowest value in the vaginal tract should be sought, but that using the probe as an adjunct to herdsman's observation would not greatly increase estrus detection rate.  相似文献   
6.
7.
Summary Self-exchange of chloride and sulfate in dog and cat red cells has been measured under equilibrium conditions. The rates of efflux for these anions are approximately twofold higher in dog compared to cat red blood cells. Although the rates differ, the anion exchange systems of these two red cell types exhibit many common properties. The dependence of35SO4 efflux on the intracellular SO4 concentration, the pH dependence and the inhibition of35SO4 efflux by Cl and SITS are almost identical in dog and cat red cells. Nystatin treatment was used to study the dependence of36Cl efflux on internal Cl. Chloride efflux exhibits saturation in both cell types with dog red cells possessing a higherV max andK 1/2 than cat red cells. The number of anion transport sites was estimated by extrapolation to the number of molecules of dihydro DIDS (H2DIDS, where DIDS is 4,4-diisothiocyano-2,2 stilbene-disulfonic acid) which were bound at 100% inhibition of transport. The results indicate that either the turnover numbers for anion transport differ in dog, cat, and human red cells or that there is heterogeneity in the function of the membrane components which bind H2DIDS.  相似文献   
8.
We have examined in two inbred rat strains basal and stress-induced increases in plasma levels of epinephrine (EPI) and norepinephrine (NE) and compared these with activities of the adrenal enzymes involved in the synthesis of catecholamines. There were no differences in basal levels of NE and EPI in plasma of adult male rats of the Wistar-Kyoto (WKY) and Brown-Norway (B-N) strains. However, following 5 min. of intermittent footshock, plasma levels of both catecholamines were twice as high in WKY rats as in B-N rats. In the adrenals of unstressed rats, activities of tyrosine hydroxylase and dopamine-beta-hydroxylase were significantly higher in B-N rats. In addition, the adrenal weights and the contents of NE but not EPI were greater in B-N rats. Thus, in these two rat strains, the capacity of the adrenal gland to synthesize and store catecholamines appeared to be inversely related to plasma levels of NE and EPI after stress. The differences between the strains appeared to be due to differences in the rates of removal of catecholamines from the peripheral circulation as well as to differences in the rate of release of catecholamines from the sympatho-adrenal medullary system. Thus biosynthetic enzyme activities need not be related directly to the capacity to release and elevate plasma levels of catecholamines following stressful stimulation.  相似文献   
9.
10.
In conscious animals, handling and immobilization increase plasma levels of the catecholamines norepinephrine (NE) and epinephrine (EPI). This study examined plasma concentrations of endogenous compounds related to catecholamine synthesis and metabolism during and after exposure to these stressors in conscious rats. Plasma levels of 3,4-dihydroxyphenylalanine (DOPA), NE, EPI, and dopamine (DA), the deaminated catechol metabolites 3,4-dihydroxyphenylglycol (DHPG), and 3,4-dihydroxyphenylacetic acid (DOPAC), and their O-methylated derivatives methoxyhydroxyphenylglycol (MHPG) and homovanillic acid (HVA) were measured using liquid chromatography with electrochemical detection at 1, 3, 5, 20, 60, and 120 min of immobilization. By 1 min of immobilization, plasma NE and EPI levels had already reached peak values, and plasma levels of DOPA, DHPG, DOPAC, and MHPG were increased significantly from baseline, whereas plasma DA and HVA levels were unchanged. During the remainder of the immobilization period, the increased levels of DOPA, NE, and EPI were maintained, whereas levels of the metabolites progressively increased. In animals immobilized briefly (5 min), elevated concentrations of the metabolites persisted after release from the restraint, whereas DOPA and catecholamine levels returned to baseline. Gentle handling for 1 min also significantly increased plasma levels of DOPA, NE, EPI, and the NE metabolites DHPG and MHPG, without increasing levels of DA or HVA. The results show that in conscious rats, immobilization or even gentle handling rapidly increases plasma levels of catecholamines, the catecholamine precursor DOPA, and metabolites of NE and DA, indicating rapid increases in the synthesis, release, reuptake, and metabolism of catecholamines.  相似文献   
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