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1.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
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Circannual variation in lymphocyte subsets, revisited   总被引:2,自引:0,他引:2  
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply.  相似文献   
4.
Peptococcus indolicus (formerly Micrococcus indolicus) is an asaccharolytic anaerobic coccus that is frequently isolated from udder secretions from cases of heifer and dry-cow mastitis (summer mastitis). To facilitate better identification and its differentiation from Peptococcus asaccharolyticus, a variety of biochemical, enzymatic, and serological properties were studied. Seventy-nine strains of P. indolicus of bovine origin and 10 strains of P. asaccharolyticus of human origin were examined using the API 20A and API-ZYM test kit systems. In addition, production of extracellular enzymes by using sensitive substrate-containing agar plate tests, production of peptocoagulase (a plasma-clotting factor), hemolytic properties, metabolic end products by gas chromatography, and serological characteristics with a set of P. indolicus typing antisera were investigated. P. indolicus and P. asaccharolyticus were not satisfactorily differentiated solely by the API 20A system. P. indolicus differed from P. asaccharolyticus in producing H(2)S, reducing nitrate to nitrite, producing peptocoagulase, possessing alkaline phosphatase, and producing large amounts of propionate from lactate. Moreover, none of the strains of P. asaccharolyticus was typable with the P. indolicus typing antisera. The majority (88%) of P. indolicus strains also gave weak hydrolysis of ribonucleic acid, and 6 out of 79 produced deoxyribonuclease. All strains in this study were sensitive to metronidazole (5 mug) by disk diffusion tests.  相似文献   
5.
Isolates of Borrelia turicatae, Borrelia parkeri, and the Florida canine borrelia (FCB) were examined to further phylogenetically characterize the identities of these spirochetes in the United States. DNA sequences of four chromosomal loci (the 16S rRNA gene, flaB, gyrB, and glpQ) were determined for eight isolates of B. turicatae and six isolates of B. parkeri, which grouped the spirochetes into two distinct but closely related taxa (>98% sequence identity) separate from Borrelia hermsii. The FCB was clearly separated with the group identified as B. turicatae, confirming this bacterium as a relapsing fever spirochete. Therefore, the potential for tick-borne relapsing fever in humans and other animals exists in Florida and future efforts are needed to determine the enzootic hosts and distribution of this spirochete in the southeastern United States. Analysis of plasmids demonstrated both linear and circular forms in B. turicatae but only linear plasmids in B. parkeri, which should be of interest to investigators concerned with plasmid diversity and evolution within this group of spirochetes.  相似文献   
6.
The piliation and hemagglutination properties of 54 consecutive Escherichia coli isolates from women with recurrent urinary tract infections were studied. Mannose-sensitive hemagglutination (MSHA) of guinea pig erythrocytes, characteristic of type 1-piliated bacteria, was produced by 75% of the isolates, 32% produced mannose-insensitive hemagglutination, and 14% produced no hemagglutination reaction. The production of type 1 pili was examined in those strains that produced MSHA only. Studies with antiserum prepared against purified pili suggested that at least three subtypes of type 1 hemagglutinins were represented among the isolates. All of the type 1-piliated isolates produced MSHA after serial subculture in static broth. After growth on agar, selected type 1-piliated isolates were subdivided into two groups. Many strains apparently suppressed piliation during growth on agar (regulated variants); all colonies became MSHA negative and were composed of nonpiliated cells as shown by electron microscopy. The loss of the MSHA phenotype often occurred after a single overnight passage on agar, and any remaining hemagglutinin was gradually lost with one to three additional passages. Seven strains, however, retained a significant hemagglutination titer after multiple subcultures on agar, and they produced colonies consisting of a mixed population of piliated and nonpiliated cells. These strains were apparently able to oscillate between states of pilus expression and nonexpression during growth on agar (random phase variants). When nonpiliated cells isolated from the mixed, random variant population were plated on agar, they gave rise to hemagglutination-positive colonies that consisted of both piliated and nonpiliated cells. The distinction between random variants and regulated variants was also observed in shaking broth cultures inoculated with nonpiliated cells. The random variants produced MSHA-positive cultures composed of piliated and nonpiliated cells, whereas the regulated strains remained nonpiliated. The results indicate that type 1 pili are a predominant adhesin of uropathogenic E. coli and that during growth on agar only about one-fourth of the type 1-piliated isolates regulate pilus expression by random phase variation.  相似文献   
7.
Fifty-six blood donor sera were examined by indirect immunofluorescence for IgG antibodies to a selection of anaerobic bacterial strains, often isolated from wound cultures. Another 25 sera were examined by IgG antibodies to six NCTC Bacteroides strains. A wide range of IgG antibody titres were found against Fusobacterium, Clostridium, and anaerobic streptococcal species. Very low titres were found against the Bacteroides strains. It is suggested that the testing of a single serum specimen for IgG antibodies against a representative collection of Bacteroides fragilis strains could be helpful in verifying a clinical suspicion of infection with these organisms.  相似文献   
8.
Fragments of plasmid DNA from Borrelia burgdorferi and B. hermsii were cloned and tested for specificity as hybridization probes to identify these two species of pathogenic spirochetes. Three fragments from the 49-kilobase-pair linear plasmid of B. burgdorferi were tested: a 500-base-pair (bp) HindIII fragment (probe 49A), a 445-bp PstI-HindIII fragment (probe 3G), and a 320-bp HindIII fragment (probe 16H). When hybridized to purified DNA or whole spirochetes, all of the probes distinguished B. burgdorferi from the other species examined, including B. hermsii, B. parkeri, B. turicatae, B. coriaceae, B. crocidurae, and B. anserina. Probe 49A was the most useful, however, hybridizing with all strains of B. burgdorferi originating from both North America and Europe while not cross-hybridizing with B. hermsii. A 790-bp HindIII fragment of B. hermsii DNA hybridized with DNA and whole spirochetes of this species and also with B. parkeri, confirming the close relatedness of these two species. These probes provide a new method of identifying these Borrelia species once the organisms have been grown in culture.  相似文献   
9.
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide dismutase (SOD) and catalase-like enzyme activity were quantified in seminal plasma from normozoospermic patients, men with known distal ductal occlusion, proven fathers and male partners of couples receiving in-vitro fertilization (IVF) treatment for both male and female causes. Glutathione was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme activities per unit volume were lower in semen from vasectomized men, suggesting that they did not originate substantially from the testis or epididymis. The strongest relationships between enzyme activities and accessory gland markers were between zinc and GRD (r = 0.678), SOD (r = 0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these enzymes. Only weak relationships between accessory gland markers and catalase-like activity suggested a multi-glandular source of this enzyme. There was no relationship between the activity of any of the enzymes in the IVF patients with their fertilization rates in vitro or the establishment of pregnancy after IVF. Nor was there any correlation of enzyme activity with the morphology and percentage of motile spermatozoa in semen or with the percentage motility of spermatozoa immediately after swim-up or after overnight incubation. These findings suggest that the protective enzymes in the seminal plasma are contributed largely by the prostate and little by the epididymis, and that in most cases of IVF, they have no major influence on the outcome.   相似文献   
10.
Campylobacter pylori was identified with immunoperoxidase staining and a mouse monoclonal antibody directed against C. pylori in gastric biopsy specimens from 24 patients with gastritis. C. pylori was not found in gastric biopsy specimens from six subjects with histologically normal mucosa. The monoclonal antibody, which was reactive with a surface protein of approximately 20 kilodaltons, was found to be specific for C. pylori, and the immunoperoxidase staining proved to be more sensitive and rapid than culture in detecting the organism. In the tissue specimens where C. pylori was detected with the monoclonal antibody, there was a strong expression of class II transplantation antigens on the epithelial cells and an increased number of T lymphocytes. These findings indicate that C. pylori may initiate local immune responses.  相似文献   
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