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51.
Published data indicate that during the last decades there is a possible change in the pattern of sensitization to different aeroallergens in adult population with atopy. The aim of this investigation was based on the hypothesis that during last 15 years there has been a change in the structure of prevalence of sensitization to different aeroallergens in adult population of Zagreb and its surroundings with atopy. Medical records from outpatient allergy clinic were screened for the period 1991-2004. We included 794 patients during years 1991-1994, 814 patients during years 1995-1999, and 969 patients during years 2000-2004. Following data were analyzed: age, gender, education level, residence, referral diagnosis, dominant symptoms, results of skin-prick test (SPT), total and specific serum immunoglobulin E. As risk factors for allergic sensitization we determined the decade of birth (p < 0.0001), male gender (p < 0.008), level of education (p < 0.0001), and place of residence (p < 0.05). Proportion of sensitized individuals to pollen significantly increased from the period 1991-1994 towards 2000-2004 (p < 0.001 for the trend) with a significant increase in the proportion of sensitized individuals to weed pollen (p = 0.002 for the trend) while the proportion of sensitized to other two groups of pollen (grasses and trees) was not significantly different. A significant increase in the proportion of sensitized individuals was determined for sensitization to ragweed pollen (p = 0.004 for the trend), and to mugwort (p = 0.005 for the trend). Despite all its limitations primarily based on the selection bias the results of this study are conclusive about the significant change in the proportion of sensitization to different aeroallergens and different pollen groups and individual pollen species during the investigated 15-year time interval.  相似文献   
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It has been shown that adult human Leydig cells express a number of neuroendocrine markers, and, therefore, could be considered as a part of the neuroendocrine system in the adult. A limited number of studies have dealt with the dynamics of development of human foetal Leydig cells, whereas studies on their neuroendocrine nature are still extremely rare. Therefore, the aim of our study was to investigate the development of human foetal Leydig cells in different weeks of gestation (wg) and to check if these cells express certain markers characteristic of the diffuse neuroendocrine system (DNS). Qualitative, quantitative histological studies and immunohistochemical analyses of human foetal testicular tissue have been performed. According to our data, Leydig cells formed a dynamic population of cells within the interstitum of testes in the period between 15 and 36 wg. The total number of Leydig cells of human foetal testes changed through different stages of gestation by means of 'pulsatile' dynamics (most likely, by following the variable level of gonadotropins). At early stages of development (15-17 wg) immunohistochemical reactions for the expression of neuron specific enolase (NSE) were positive within sex cords and between them, in the interstitum. Pro-spermatogonia in the sex cords were positive, as well as elongated spindle-shaped cells of the interstitum (very likely, precursors of Leydig cells). During the later stages of development (28-36 wg), excluding the pro-spermatogonia, the interstitial Leydig cells were also positive. The results of the immunohistochemical analyses (the expression of NSE) confirmed the hypothesis that human foetal Leydig cells were of neuroendocrine nature.  相似文献   
54.
We demonstrate the evolution of the clinical presentation and outcomes for patients with clinically localized prostate cancer (PC) treated with radical retropubic prostatectomy (RRP) at our department, emphasizing epidemiologic significance of changes during the 10-year period. We assessed the annual trends for changes in patients age, preoperative prostate specific antigen (PSA), preoperative versus postoperative stages and Gleason grades, organ confined status and surgical margin status. A total of 488 RRPs were performed from January 1996 to December 2005 with the annual frequency increased from 8 to 129 (1512.5%). Mean patient age increased from 61.5 to 66.12 years in 2005, with the percentage of men aged more than 70 years increased from 12.5 to 26.5%, respectively. The detection of PC based solely on pathological PSA levels (as indication for prostate biopsy) rose impressively from 25.5 to 70% and the rates of postoperative organ-confined disease also increased significantly from 25 to 74.7%. Mean preoperative PSA decreased from 16.7 to 9.89 ng/mL. On the contrary, there was an increase in percentage of patients with preoperative PSA values ranging from 4 to 10 ng/mL (from 20 to 65.4%). Positive surgical margin rate decreased from 49.4 to 25% and percent of patients receiving neoadjuvant therapy decreased from 78.5 to 5.4%. Proportion of patients who were undergraded decreased from 75.1 to 31.7%. The rates of understaging have remained relatively stable over the years. During the study period, PC was increasingly detected by prostate biopsy on the basis of a pathological PSA level only and shifted significantly to more organ-confined stages with more favourable outcomes for pathological variables due to a more accurate assessment of clinical stage prior to surgery, reduced use of neoadjuvant therapy and improved surgical technique. Our data also argue strongly that routine PSA testing should be expanded and not restricted.  相似文献   
55.
Myelin basic protein isolated by a single step with the cationic detergent cethyltrimethylammonium bromide in a lipid-bound form is able to induce structural transition of lysophosphatydilcholine micelles into multi-laminar vesicles. This finding, observed through electron microscopy, is discussed in the light of the assumed ability of the basic protein to organize myelin lipids.  相似文献   
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The distribution of the stage-specific embryonic antigen SSEA-3 was studied immunohistochemically on postimplantation mouse embryos. This carbohydrate antigen, identified as an epitope of a globo-series ganglioside isolated from human teratocarcinoma cells (Kannagi et al., 1983, J. Biol. Chem.258, 8934–8942) was originally detected on the zygote and mouse early cleavage-stage embryos. It disappears on the early blastocyst and reappears on the primitive endoderm of the implanting blastocyst (Shevinsky et al., 1982, Cell30, 697–705). We now show in the early egg cylinder (on the sixth day of pregnancy) SSEA-3 is present in the entire visceral endoderm but not in any other part of the conceptus. From Day 7 of pregnancy onward, SSEA-3 is restricted to the extraembryonic visceral endoderm and the visceral yolk sac cells. Therefore, SSEA-3 is a useful marker for this endodermal cell lineage in midgestational mouse embryos.  相似文献   
58.
Deinococcus radiodurans is one of the most radiation-resistant organisms known. It can repair hundreds of radiation-induced double-strand DNA breaks without loss of viability. Genome reassembly in heavily irradiated D. radiodurans is considered to be an error-free process since no genome rearrangements were detected after post-irradiation repair. Here, we describe for the first time conditions that frequently cause erroneous chromosomal assemblies. Gross chromosomal rearrangements have been detected in recA mutant cells that survived exposure to 5 kGy γ-radiation. The recA mutants are prone also to spontaneous DNA rearrangements during normal exponential growth. Some insertion sequences have been identified as dispersed genomic homology blocks that can mediate DNA rearrangements. Whereas the wild-type D. radiodurans appears to repair accurately its genome shattered by 5 kGy γ-radiation, extremely high γ-doses, e.g., 25 kGy, produce frequent genome rearrangements among survivors. Our results show that the RecA protein is quintessential for the fidelity of repair of both spontaneous and γ-radiation-induced DNA breaks and, consequently, for genome stability in D. radiodurans. The mechanisms of decreased genome stability in the absence of RecA are discussed.  相似文献   
59.
Rural areas, where 47.6% of the Croatian population lives are not generally the focus of research; yet there are challenges which affect the rural population that often go unreported. These communities often exhibit disadvantages in many areas of health. The aim of this study is to examine the specific health needs and related determinants of rural populations influenced by transition that were affected by the consequences of war. The focus of the research is rural lifestyle, behaviour and cardiovascular risk factors in three villages of Sisacko-moslavacka County. Results show that participants generally understand that their own lifestyles influence their health, but they often neglect to change their behaviour to improve their health. This can be explained through complex socio-economic conditions and traditional values of their heritage. These results suggest a need for further research on health status, attitude, and behaviour of Croatia's rural population. Specific public health intervention and services for rural populations must be promoted.  相似文献   
60.
The benefits of ever-growing numbers of sequenced eukaryotic genomes will not be fully realized until we learn to decipher vast stretches of noncoding DNA, largely composed of transposable elements. Transposable elements persist through self-replication, but some genes once encoded by transposable elements have, through a process called molecular domestication, evolved new functions that increase fitness. Although they have conferred numerous adaptations, the number of such domesticated transposable element genes remains unknown, so their evolutionary and functional impact cannot be fully assessed. Systematic searches that exploit genomic signatures of natural selection have been employed to identify potential domesticated genes, but their predictions have yet to be experimentally verified. To this end, we investigated a family of domesticated genes called MUSTANG (MUG), identified in a previous bioinformatic search of plant genomes. We show that MUG genes are functional. Mutants of Arabidopsis thaliana MUG genes yield phenotypes with severely reduced plant fitness through decreased plant size, delayed flowering, abnormal development of floral organs, and markedly reduced fertility. MUG genes are present in all flowering plants, but not in any non-flowering plant lineages, such as gymnosperms, suggesting that the molecular domestication of MUG may have been an integral part of early angiosperm evolution. This study shows that systematic searches can be successful at identifying functional genetic elements in noncoding regions and demonstrates how to combine systematic searches with reverse genetics in a fruitful way to decipher eukaryotic genomes.  相似文献   
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