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11.
Cigarette smoking is an important risk factor for all respiratory tract diseases. Unfortunately, the symptoms develop slowly, thus patients feel the consequences of the slowly developing inflammation too late. The inflammation first develops in the area of respiratory bronchioles. In this stage, the disease is asymptomatic. The study included a sample of 31 smokers, mean age 36.38 years, with normal spirometry indices, acid-base status and arterial blood gases. The mean smoking index was 11.28 smoking/years. All subjects were healthy, without any subjective health problems or disease indicators. The aim was to define dead lung area (V/Q) as an early indicator of changes in smokers. Study results demonstrated the mean shunt value in smokers of 8.25%, which showed positive correlation with smoking. The shunt size yielded negative correlation with the forced expiratory volume in one second and midexpiratory flow in smokers. In conclusion, determination of lung shunt is a simple method that is sensitive enough in the diagnosis of initial lung lesion due to cigarette smoking.  相似文献   
12.
In the forest of Kljestevica, the elm is attacked by four species of elm bark beetles: Scolytus multistriatus (Marsh.), Scolytus scolytus (Fab.), Scolytus pygmaeus (Fab.) and Scolytus ensifer (Rich.) (Col., Scolytidae). Scolytus multistriatus and S. pygmaeus are the most numerous species. Elm bark beetle is parasitized by four species of parasites: Dendrosoter protuberans (Nees), Ecphylus silesiacus (Ratz.), Coeloides scolyticida (Wesm.) (Hym., Braconidae) and Entedon leucogramma (Ratz.) (Hym., Eulophidae). Ecphylus silesiacus and D. protuberans are the most numerous species. The nectar of mustard ( Sinapis alba L., Brassicaceae) flowers, sweet basil ( Stachys recta L., Lamiaceae) flowers and of wild carrot ( Daucus carota L., Umbelliferae), has an important effect on the number of parasites and on the parasitism of the elm bark beetles. Wild carrot is the most attractive plant to the parasites for additional nutrition, especially for D. protuberans . Mustard and sweet basil flowers are suitable for additional nutrition of E. silesiacus imagos. On meadow flowers growing spontaneously in forest clearings, the lowest number of parasite imagos was collected by an entomological catcher, and the lowest percentage of parasitized larvae and eggs of the elm bark beetle was recorded in elm control catch trunks that were not near the cultivated melliferous plants.  相似文献   
13.
14.
In the school-year 2002/2003 a prospective epidemiological study was performed with the aim of evaluating the prevalence and distribution of scoliosis in the population of schoolchildren from Mostar, Bosnia and Herzegovina. The general check-up of primary-school children covered a total of 2,517 children aged 7-14. The children in which at least one positive symptom of scoliosis was found were directed to undergo orthopedic examination and--if indicated--radiography. Incorrect posture was noted in 33.4% of children, and 11.8% of children were sent to orthopedic specialist examination. The prevalence of structural scoliosis amounted to 3.1%, with the spine curvature threshold being 10 degrees. In eight children (0.32%; 1 boy and 7 girls) a curvature of 20 degrees or more was diagnosed. The most common type of curvature was the thoracal (39%) and the thoraco-lumbar (39%) while 14 children had a double curvature (17.8%). A scoliosis was detected due to here performed check-up in 83.5% of children with scoliosis. No case of serious spine deformity (45 degree or more) was recorded, due to regular general check-ups taking place biannually in this population.  相似文献   
15.
Nitric oxide (NO) is generated intracellularly from L-arginine by the action of the enzyme nitric oxide synthase (NOS). The present investigation demonstrates immunoreactivity against NOS and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase activity in nerve cells and fibers of the reproductive system of the female mouse. The density of nerve fibers staining for NOS varied among different genital organs. The ovary and Fallopian tube were devoid of NOS-positive nerves. The uterine horns received sparse innervation by NOS-containing nerve fibers. The most abundant NOergic innervation was found in the uterine cervix and vagina, where the nerve fibers ran parallel to the smooth muscle bundles and beneath the epithelium; they also accompanied intramural blood vessels. The vaginal muscular wall contained single or groups of NOS-reactive nerve cells. Clusters of NOS-containing neurons were located in Frankenhäuser's ganglion at the cervico-vaginal junction. NO may therefore act as a transmitter in the nervous control of the female reproductive tract.  相似文献   
16.
The process of electrostatic extrusion as a method for cell immobilization was investigated that could be used for potential applications in medicine. An attempt was made to assess the effects of cell addition and polymer concentration on the overall entrapment procedure, ie, on each stage of immobilization: polymer-cell suspension rheological characteristics, electrostatic extrusion process, and the process ofgelation. The findings should contribute to a better understanding of polymer-cell interactions, which could be crucial in possible medical treatments. Alginate-yeast was used as a model system for carrier-cells. The electrostatic extrusion was considered as a complex two-phase flow system and the effects of cell and alginate concentrations on the resulting microbead size and uniformity were assessed. Under investigated conditions, microbeads 50-600 microm in diameter were produced and the increase in both alginate and cell concentrations resulted in larger microbeads with higher standard deviations in size. We attempted to rationalize the findings by rheological characterization of the cell-alginate suspensions. Rheological characterization revealed non-Newtonian, pseudoplastic behavior of cell-alginate suspensions with higher viscosities at higher alginate concentrations. However, the presence of cells even at high concentrations (5x10(8) and 1x10(9) cells/mL) did not significantly affect the rheological properties of Na-alginate solution. Lastly, we investigated the kinetics of alginate gelation with respect to the quantity of Ca2+ ions and cell presence. The gelation kinetics were examined under conditions of limited supply with Ca2+ ions, which can be essential for immobilization of highly sensitive mammalian cells that require minimal exposure to CaCl2 solution. The molar ratio of G units to Ca2+ ions of 3.8:1 provided complete crosslinking, while the increase in alginate concentration resulted in prolonged gelation times but higher strength of the resulting gel. The cell presence decreased the rate of network formation as well as the strength of the obtained Ca-alginate hydrogel.  相似文献   
17.
The aim of this study was to investigate metabolites of the lichen Laurera benguelensis. A high-performance liquid chromatographic (HPLC) method has been developed for the characterization of xanthones and anthraquinones in extracts of this lichen. Lichexanthone, secalonic acid D, norlichexanthon, parietin, emodin, teloschistin and citreorosein were detected in the lichen samples, which were collected from two places in Thailand. Components of the lichen were identified by relative retention time and spectral data. This is the first time that a detailed phytochemical analysis of the lichen L. benguelensis was reported and this paper has chemotaxonomic significance because very little has been published on the secondary metabolites present in Laurera species. Some of the metabolites were detected for the first time in the family Trypetheliaceae. The results of preliminary testing of benzene extract and its chloroform and methanol fractions showed that all samples showed a weak radical scavenging activity. The chloroform extract showed the highest antioxidant activity.  相似文献   
18.
The most favourable period for Dendrosoter protuberans development occurred when wasps were introduced 16 days after the beginning of Scolytus multistriatus development (the greatest number of emerged wasps per a single parasitoid female with a very positive sexual index and high percentage of parasitised elm bark beetle larvae). No significant differences were observed in parasitoid efficiency between the 11th and the 21st day. The most unfavourable period for elm bark beetle parasitisation was six days after the beginning of S. multistriatus development (a low reproduction of D. protuberans, a negative sexual index and a low number of destroyed S. multistriatus larvae). The reproduction of both the elm bark beetle and D. protuberans was greater in the first, than in the second generation. The developmental period of D. protuberans in the first generation was approximately two days longer than in the second generation. Furthermore, the development of females was 1-2 days longer than the development of males. D. protuberans developed most successfully on S. multistriatus (the most abundant parasitoid reproduction with the longest developmental period and a very positive sexual index that resulted in a high percentage of parasitised larvae) and then on S. ensifer, S. pygmaeus and Pteleobius kraatzi. On the other hand, S. scolytus larvae were the poorest host of all elm species - the reproduction of D. protuberans in this species was the scarcest with the shortest period of development and a negative sexual index, hence larval parasitisation was the lowest.  相似文献   
19.
The expression and distribution of nitric oxide synthase (NOS) was studied by use of the newly designed specific histochemical NADPH diaphorase staining method and the indirect immunofluorescence technique employing an antiserum to brain NOS in visceral and somatic striated muscles of several mammalian species. Histochemical activity and immunoreactivity were located in the sarcolemma region of type I and II fibers of all muscles investigated. Visceral muscles were more strongly stained than somatic muscles. Furthermore, type II fibers, identified by staining of myosin adenosine triphosphatase activity after pre-incubation at alkaline pH, were more intensely labeled than type I fibers. In addition, NOS activity was detected in the area of the sarcolemma of intrafusal fibers. No obvious differences between species were observed. It was concluded that NOS of striated muscles probably makes up the richest and most important nitric oxide source in mammals.  相似文献   
20.
Summary Recently, it has been shown that in human striated muscle the signalling enzyme, brain-type nitric oxide synthase I (NOS I), is associated with the sarcolemma and complexes with dystrophin and/or members of the dystrophin complex. In order to find out whether there exists a regular association between NOS I and the complex, muscle biopsies from patients with various muscle disorders were analysed by enzyme histochemistry and immunohistochemistry. In patients suffering from Duchenne muscular dystrophy, and to a lesser extent in those with Becker-type dystrophy, NOS I and dystrophin complex components were absent or drastically reduced in the sarcolemma region. In other dystrophies, as well as in metabolic and inflammatory myopathies, NOS I and dystrophin complex constituents were expressed normally, while in the case of neurogenic diseases leading to denervation atrophy and especially congenital idiopathic clubfoot, the immunohistochemical patterns of the distribution of the dystrophin complex constituents were normal, but NOS I activity and protein were deficient or dramatically diminished. The results can be interpreted as indicating that, in general, NOS I targeting to the sarcolemma is dependent on particular members of the dystrophin complex, such as ·-1 syntrophin, yet the expression and/or positioning of NOS I may be under the control of further factors, probably of neurogenic origin. NOS I-associated diaphorase may thus be a useful complementary tool in the diagnosis of muscle disorders. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
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