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1.
BackgroundAlthough several computer-aided computed tomography (CT) analysis methods have been reported to objectively assess the disease severity and progression of idiopathic pulmonary fibrosis (IPF), it is unclear which method is most practical. A universal severity classification system has not yet been adopted for IPF.ObjectiveThe purpose of this study was to test the correlation between quantitative-CT indices and lung physiology variables and to determine the ability of such indices to predict disease severity in IPF.MethodsA total of 27 IPF patients showing radiological UIP pattern on high-resolution (HR) CT were retrospectively enrolled. Staging of IPF was performed according to two classification systems: the Japanese and GAP (gender, age, and physiology) staging systems. CT images were assessed using a commercially available CT imaging analysis workstation, and the whole-lung mean CT value (MCT), the normally attenuated lung volume as defined from −950 HU to −701 Hounsfield unit (NL), the volume of the whole lung (WL), and the percentage of NL to WL (NL%), were calculated.ResultsCT indices (MCT, WL, and NL) closely correlated with lung physiology variables. Among them, NL strongly correlated with forced vital capacity (FVC) (r = 0.92, P <0.0001). NL% showed a large area under the receiver operating characteristic curve for detecting patients in the moderate or advanced stages of IPF. Multivariable logistic regression analyses showed that NL% is significantly more useful than the percentages of predicted FVC and predicted diffusing capacity of the lungs for carbon monoxide (Japanese stage II/III/IV [odds ratio, 0.73; 95% confidence intervals (CI), 0.48 to 0.92; P < 0.01]; III/IV [odds ratio. 0.80; 95% CI 0.59 to 0.96; P < 0.01]; GAP stage II/III [odds ratio, 0.79; 95% CI, 0.56 to 0.97; P < 0.05]).ConclusionThe measurement of NL% by threshold-based volumetric CT analysis may help improve IPF staging.  相似文献   
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The intestinal epithelium contains columnar epithelial cells (ECs) and M cells, and fucosylation of the apical surface of ECs and M cells is involved in distinguishing the two populations and in their response to commensal flora and environmental stress. Here, we show that fucosylated ECs (F-ECs) were induced in the mouse small intestine by the pro-inflammatory agents dextran sodium sulfate and indomethacin, in addition to an enteropathogen derived cholera toxin. Although F-ECs showed specificity for the M cell-markers, lectin Ulex europaeus agglutinin-1 and our monoclonal antibody NKM 16-2-4, these cells also retained EC-phenotypes including an affinity for the EC-marker lectin wheat germ agglutinin. Interestingly, fucosylation of Peyer’s patch M cells and F-ECs was distinctly regulated by α(1,2)fucosyltransferase Fut1 and Fut2, respectively. These results indicate that Fut2-mediated F-ECs share M cell-related fucosylated molecules but maintain distinctive EC characteristics, Fut1 is, therefore, a reliable marker for M cells.  相似文献   
4.
In Japan, although greenhouse whitefly, Trialeurodes vaporariorum (Westwood), and sweet potato whitefly, Bemisia tabaci (Gennadius), co-occur on tomato plants under greenhouse conditions, the two whiteflies are distributed differently with regard to leaf position. To elucidate the factors that determine the leaf position of these whiteflies, we investigated traits for leaflets collected from three positions on tomato plants. Furthermore, we examined leaflet selection by and fertility of the two whiteflies under choice and non-choice conditions. In addition, the effect on whitefly behavior of volatile compounds released from leaflets was evaluated by use of a Y-tube olfactometer test. Nitrogen and carbon content were highest for upper leaflets. In choice tests, more T. vaporariorum and B. tabaci adults selected upper and middle leaflets, respectively. Similarly, they oviposited more eggs on upper and middle leaflets. In non-choice tests, T. vaporariorum oviposited more eggs on upper leaflets, but B. tabaci oviposited equally on each leaflet. In Y-tube olfactometer tests, more T. vaporariorum adults moved to upper leaflets whereas more B. tabaci adults moved to middle leaflets. These results suggest that different leaflet selection by adults of these two whiteflies is likely to be associated with the different volatile compounds emitted by tomato leaflets at each position.  相似文献   
5.
Receptor-mediated superoxide (O2.-)-generation and tyrosyl phosphorylation of neutrophil proteins, such as 58, 65, 84, 108 and 115 kDa, were enhanced by priming cells with granulocyte colony stimulating factor (G-CSF) [Akimura, K. et al. Arch. Biochem. Biophys. 298: 703-709, 1992]. To elucidate the possible involvement of tyrosyl phosphorylation of neutrophil proteins in the enhancing mechanism of O2.- generation, the effect of cepharanthine, a biscoclaurine alkaloid that inhibits phorbol 12-myristate 13-acetate (PMA)- and receptor-mediated O2.- generation, on the priming of human peripheral neutrophils (HPPMN) was studied. Both enhancement of formyl-methionyl-leucyl- phenylalanine (FMLP)-mediated O2.- generation and tyrosyl phosphorylation of some neutrophil proteins, i.e., 115, 108 and 84 kDa proteins, by HHPMN after treatment with G-CSF were strongly inhibited by cepharanthine in a concentration- and treatment-time-dependent manner. In contrast, inhibition of PMA-mediated O2.- generation by cepharanthine was weak and independent of treatment time. These results suggest that cepharanthine might inhibit the priming step of neutrophil activation concomitantly with its inhibition of the tyrosyl phosphorylation of some neutrophil proteins that might underlie the mechanism for priming of neutrophils with G-CSF.  相似文献   
6.
Fischer rats were a fed diet supplied with copper chloride (150–600 ppm) for 60 d from weaning. Serum (glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) activities were increased with the increase of Cu concentration in the diet. Biliary excretion of Cu was related to the dietary Cu level. Depositions of hepatic and renal Cu were also related to the dietary Cu level in a dose-dependent manner. In particular, hepatic (155.2±13.3 μg/g) and renal (44.9±4.4 μg/g) Cu concentrations increased abruptly in the Cu-600 ppm group. In the liver, about 60% of Cu was distributed in the soluble fraction (100,000 g supernatant). In the Cu-600 ppm group, 25% of cystosolic Cu was bound to metallothionein (MT). Our results suggest that chronic exposure to Cu appears to have a deleterious effect on the hepatic function, and further, that even in rats with normal biliary Cu excretion, clearance of Cu from the liver may be marginal when dietary Cu is near the 600-ppm level. Although Cu is an essential nutrient, an overload of Cu should be avoided.  相似文献   
7.
Animals decerebrated at the precollicular-premammillary body level exhibit spontaneous locomotion without any artificial stimulation. Our laboratory reported that the cardiovascular and autonomic responses at the onset of spontaneous locomotor events are evoked by central command, generated from the caudal diencephalon and the brain stem (Matsukawa K, Murata J, and Wada T. Am J Physiol Heart Circ Physiol 275: H1115-H1121, 1998). In this study, we examined whether central command and/or a reflex resulting from muscle afferents modulates arterial baroreflex function using a decerebrate cat model. The baroreflex was evoked by stimulating the aortic depressor nerve (ADN) at the onset of spontaneous muscle contraction (to test the possible influence of central command) and during electrically evoked contraction or passive stretch (to test the possible influence of the muscle reflex). When the ADN was stimulated at rest, heart rate and arterial blood pressure decreased by 40 +/- 2 beats/min and 11 +/- 1 mmHg, respectively. The baroreflex bradycardia was attenuated to 55 +/- 4% at the onset of spontaneous contraction. The attenuating effect on the baroreflex bradycardia was not observed at the onset and middle of electrically evoked contraction or passive stretch. The depressor response to ADN stimulation was identical among resting and any muscle interventions. The inhibition of the baroreflex bradycardia during spontaneous contraction was seen after beta-adrenergic blockade but abolished by muscarinic blockade, suggesting that the bradycardia is mainly evoked through cardiac vagal outflow. We conclude that central command, produced within the caudal diencephalon and the brain stem, selectively inhibits the cardiac component, but not the vasomotor component, of the aortic baroreflex at the onset of spontaneous exercise.  相似文献   
8.
We isolated Bartonella henselae from an inguinal lymph node of a 36-year-old male patient with cat-scratch disease. The patient had many areas of erythema on his body, swelling of the left inguinal lymph nodes with pain and slight fever. The diagnosis was made on the basis of polymerase chain reaction for B. henselae DNA from the lymph node biopsies and blood sample, and isolation of the organism, histology of the lymph node and serology with an indirect immunofluorescent antibody test. We also analyzed the genome profiles for five strains of 90 isolates from the lymph node by pulsed-field gel electrophoresis after Not I endonuclease digestion. We found two different genomic profiles. These results suggest that the patient had been either co-infected or re-infected with two genetically different strains of B. henselae.  相似文献   
9.
To characterize the ability of bifidobacteria to affect the production of macrophage-derived cytokines, a murine macrophage-like cell line, J774.1, was cultured in the presence of 27 strains of heat-inactivated bifidobacteria. Bifidobacterium adolescentis and B. longum, known as adult-type bifidobacteria, induced significantly more pro-inflammatory cytokine secretion, IL-12 and TNF-alpha, by J774.1 cells, than did the infant-type bifidobacteria, B. bifidum, B. breve, and B. infantis (P<0.01). In contrast, B. adolescentis did not stimulate the production of anti-inflammatory IL-10 from J774.1 cells as the other tested bacteria did. The results suggest that the adult-type bifidobacteria, especially B. adolescentis, may be more potent to amplify but less able to down-regulate the inflammatory response.  相似文献   
10.
It has been reported that inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase suppress cell proliferation and induce apoptosis. One inhibitor which induces apoptosis is mevastatin. However, the molecular mechanism of apoptosis induction is not well understood so the effects of mevastatin on various functions of HL-60 cells were investigated. We confirmed that mevastatin activated caspase-3 by release of cytochrome c (Cyt. c) from mitochondria through a membrane permeability transition mechanism and also induced typical fragmentation and ladder formation of DNA in HL-60 cells. These effects were inhibited by mevalonate, a metabolic intermediate of cholesterol biosynthesis. Mevalonate and geranylgeraniol (GGOH) inhibited DNA fragmentation whereas farnesol (FOH) did not. Mevastatin also induced cell differentiation to monocytic cells via a mevalonate inhibitable mechanism. Furthermore, mevastatin decreased the amount of an isoprenylated membrane bound Rap1 small GTPase concomitant with an increase in cytosolic Rap1 which occurred before apoptosis and differentiation. On the contrary, both mevastatin and geranylgeranylacetone (GGA), which competes with geranylgeranyl pyrophosphate, induced membrane depolarization of isolated mitochondria without swelling and Cyt. c release. These results suggest that mevastatin-induced apoptosis of HL-60 cells might be caused indirectly by activation of the caspase cascade through the modulation of mitochondrial functions and that some relationship between a certain small GTPase molecule, such as Rap1, and mevastatin-induced apoptosis may exist.  相似文献   
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