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161.
Recently it was demonstrated by Gautam, et al. that release of neutrophil-borne heparin-binding protein (HBP), also known as CAP37/azurocidin, induced endothelial hyperpermeability and neutrophil efflux. Here, we show that chronic leg ulcer fluid, in contrast to wound fluid from acute wounds, contains highly increased levels of HBP. Immunohistochemistry demonstrated the presence of HBP in chronic ulcer tissues. Furthermore, secreted products of Pseudomonas aeruginosa were found to induce release of HBP from human neutrophils. Our data suggest a possible link between bacterial presence and HBP-release in chronic ulcers. Thus, targeting HBP offers an interesting option for reduction of endothelial barrier dysfunction in chronic ulcers.  相似文献   
162.
Background Cutaneous surgery for removal of small skin tumors is usually performed as elliptical excision. There is some indication that circular excisions could result in cosmetically more favorable scars and should therefore be considered as an alternative method.Objective The aim of this study was to compare circular and elliptical excisions with respect to scar area and cosmetic result.Methods Fifty-six operations were performed, 27 elliptical and 29 circular. The cosmetic results were determined as patients opinion by questionnaire and assessment of photo slides by three independent observers. Also, scar areas were measured by computer program.Results The scar area was significantly smaller after circular excisions compared with elliptical excisions after 6 and 12 months of observation (p = 0.005 and p = 0.001, respectively). The assessment of cosmetic results by the patients did not differ between the two groups (p = 0.44), while the independent observers slightly favored the cosmetic outcome of elliptical scars (p = 0.03). When analyzing only excisions without complications, there was no difference in cosmetic results between the two groups.Conclusion Circular excisions seemed to cause smaller scars and equal cosmetic results compared with traditional elliptical excisions and could therefore be an alternative method for small skin excisions on the trunk and extremities.
SommaireAntécédents La chirurgie visant lablation de petites tumeurs cutanées est souvent effectuée par excision elliptique. Certaines données indiquent toutefois que lablation circulaire produirait des cicatrices plus acceptables du point de vue cosmétique et devrait donc être considérée comme méthode alternative.Objectif Lobjectif de cette étude est la comparaison entre les ablations elliptiques et circulaires en ce qui a trait aux cicatrices et aux résultats cosmétiques.Méthode 56 opérations ont été effectuées, 27 elliptiques et 29 circulaires. Les résultats cosmétiques ont été déterminés par lopinion des patients qui ont répondu á un questionnaire et par lévaluation des photos par trois observateurs indèpendants. Également, les régions cicatrisées ont été mesurées par un programme informatique.Résultats Les cicatrices étaient considérablement plus petites dans le cas des chirurgies circulaires, à la suite dune observation au 6e mois et au 12e mois (p = 0.005 et p = 0.001, respectivement). Il ny avait pas une grande différence entre les résultats cosmétiques des deux groupes de patients (p = 0.44). Les observateurs indépendants ont légérement favorisé les résultats des cicatrices elliptiques (p = 0.03). Lanalyse des excisions sans complications na montré aucune différence dans les résultats cosmétiques entre les deux groupes.Conclusion Les excisions circulaires semblent produire des cicatrices plus petites avec le même résultat cosmétique que les excisions elliptiques traditionnelles. Par conséquent, elles pourraient représenter une méthode alternative pour les opérations dablation des tumeurs cutanées sur le tronc et les extrémités.
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163.
Natural preparations for replenishing of hyaluronic acid of zoogenous origin used till now, are characterized with quit low biocompatibility and also too short effect of their action. Recently worked out synthetic polyvinylpyrrolidone preparation PVP, contains modification constituting internally netting of microgels to improve polymer bioresistance. The introduce modification can, however influence PVP biocompatibility after deposition into tissues of the living organism. The aim of research was evaluation of the local reaction of muscular tissue after PVP infection. The results of research concerned a control group where normal saline was used for infections. The research was carried out on 18 Wistar rats and included macroscopic and histologic observations made in the 3rd, 5th, 7th, 14th and 30th day after PVP injection into thigh muscle. The local reaction of muscular tissue was macroscopically characterized with inflammatory reaction till the 7th day after PVP injection, in later terms the observed changes disappeared. Microscopic research showed that PVP till the 7th day after PVP injection caused rather strong diffuse non-specific inflammatory process, yet without essential participation of neutrophils leading to producing of loose intra-muscular. Connective tissue in a later term. The carried out tests showed presence of PVP in muscular tissue till the 30th day after injection.  相似文献   
164.
Internally netted miscogelatinated preparation on the basis of polyvinylpyrrolidone PVP desioned for viscosuplementation of joint fluid was worked out. Netted structure of microgel grains presents larger resistance to the degrading action of free radicals than analogical linear polymer chains. Application of zoogeous preparations of hyaluronic acid results in short-term effects of their usage in evoking reaction foreign protein. Replenishment of joint fluid with preparation with higher biostability from biocompatible synthetic polymer-polyvinylpyrrolidone could improve the function of synovial through restoration of its proper viscosity and protection of the joint for a longer period of time. The aim of the experiment was determination of bioresistance and reaction of microgel PVP on the tissues of synovial joint. The tests were carried out on 10 white New Zealand rabbits after injection PVP into the knee joint for 3, 7, 14 and 30 days and submitted to macroscopic and histological evaluation. The results of tests were compared with the data obtained after injection of normal saline. Macroscopically, there were no changes in the limits of articular capsule and cartilage; there was only slight and enlargement of synovial membrane in the first 7 days after PVP injection. In histological tests it was observed that reaction in the knee joint after PVP injection was characterised it single inflammatory chains without essential participation of neutrophils observed only in synovial membrane and limited to places were tested preparation was seen. Microgel PVP was present in diverticula of synovial membrane to 30th day after injection.  相似文献   
165.
The kinetics of the acute inflammatory response of the lung was triggered in CD-1 mice by a single intratracheal instillation of a large amount of Se (10 mg); it was studied by quantitative cytology of bronchoalveolar lavage samples, light microscopy, and scanning electron microscopy coupled with x-ray elemental microanalysis. Bronchoalveolar lavage leukocytes were mostly neutrophils and increased from 12 to 24 h of Se treatment and decreased at 72 h. Only less than half of the granulocytes showed ingested Se particles; in contrast, virtually all BAL macrophages contained Se particles. Scanning electron microscopy coupled with X-ray elemental microanalysis revealed that the intracellular Se particles were heterogeneous in size (diameters from 0.4 and up to 14 microm), and that Se inclusions were sometimes accumulated at a pole of the cell. At 72 h after instillation of the particles, Se-loaded alveolar macrophages were migrated in the interstitial space of the alveoli. Se-positive regions had a focal distribution in the lung; accumulation of inflammatory cells erased the alveolar architecture of these areas of the deep lung. Our data indicates that Se overloading of the lung results in: (1) an acute inflammatory response that is dominated by neutrophils; (2) early removal of Se done mostly by alveolar macrophages, and (3) formation of focal areas of invasion of the lung parenchyma by inflammatory infiltrates.  相似文献   
166.
The telephone provides an easy-to-use, reliable and cheap computer interface. We review computer telephony applications for patient care, clinical research and medical education. We describe uses at our academic health sciences centre and discuss strengths and weaknesses of this technology. Until more sophisticated interfaces, for example personal digital assistants with wireless Internet access, are commonplace, we believe computer telephony can play a useful role in electronic healthcare.  相似文献   
167.
PURPOSE: Tangier disease is an autosomal recessive disorder in which cholesterol-rich lipids are deposited at various tissues of the body including the cornea. In this case report, the corneal changes in a patient with Tangier disease are described. METHODS: A 72-year-old patient who was diagnosed with Tangier disease 25 years before received a complete eye examination including confocal microscopy and Cochet-Bonnet esthesiometry. RESULTS: Slit-lamp biomicroscopy and confocal microscopy showed bilateral corneal opacifications caused by lipid accumulation. Confocal microscopy showed that pathologic changes in the cornea in Tangier disease are limited to the stroma. Neither a reduced corneal sensation nor lid abnormalities as previously described in Tangier disease were found. CONCLUSION: Confocal microscopy helps to identify corneal changes in the stroma caused by Tangier disease easily missed in a slit-lamp examination. The ocular manifestations of Tangier disease do not necessarily include a reduced corneal sensitivity and lid abnormalities.  相似文献   
168.
The aim of the present study was to determine the proportion of gamma/delta T-lymphocytes and CD16/CD56 (CD3- and CD3+) cells in the peripheral blood of children and adolescents with Graves' disease (GD; n = 27; mean age, 15.5 +/- 5.1 y) and nontoxic nodular goiter (NTNG; n = 25; mean age, 15.2 +/- 5.7 y), in comparison with sex- and age-matched healthy control subjects (n = 25; mean age, 15.9 +/- 2.4 y). In addition, in patients with GD, we investigated the effect of methimazole therapy on the proportion of these cells. We also looked for associations among the parameters investigated. The percentages of gamma/delta TCR+CD3+ lymphocytes and CD3+, CD16/56+CD3+, and natural killer (NK) cells were analyzed by the three-color flow cytometry using a Coulter EPICS XL cytometer. In patients with untreated GD, we observed a significant decrease in gamma/delta T (CD3+) (p < 0.002), CD16/56(CD3+) (p < 0.001), and NK (p < 0.001) cells in comparison with the healthy control subjects. After 2-6 mo of methimazole therapy, the percentages of gamma/delta TCR+CD3+ and CD16/56(CD3+) cells in peripheral blood of hyperthyroid patients returned to the normal values, whereas the percentages of NK cells normalized after 18-24 mo of therapy. These abnormalities were absent in children and adolescents with NTNG. Furthermore, there was no difference in the percentage of CD3+ lymphocytes in all of the groups. In the patients with untreated GD, we found a negative correlation between free thyroxine concentration in blood serum and the percentages of CD16/56 (CD3-) and gamma delta T cells (r = -0.5, p < 0.035; r = -0.4, p < 0.02). No such correlation was detected in patients with NTNG. We conclude that the abnormal distribution of CD16/CD56 (CD3- and CD3+) cells and gamma/delta T lymphocytes in the peripheral blood in children and adolescents with untreated GD suggests their role in the development of autoimmunity.  相似文献   
169.
Graves' disease (GD) is an autoimmune thyroid disease caused by immunological abnormality. The immune cells (lymphocytes T and B) which infiltrate the thyroid gland play a key role in the development of autoimmune thyroid disease (AITD). The aim of this study was to evaluate the differences between distribution of T (CD3) lymphocytes, subsets CD4, CD8, and their memory (CD45RO), and naive (CD45RA) T cells and B (CD19) lymphocytes in the peripheral blood of patients with Graves' disease (GD) (n = 33, mean age 15.9 +/- 5.9 years) and non-toxic nodular goiter (NTNG) (n = 25, mean age 15.2 years), in comparison to age- and sexmatched healthy control subjects (n = 25, mean age 15.9 years). The percentages of peripheral blood lymphocyte subsets were analyzed by three-color flow cytometry using a Coulter EPICS XL cytometer. In the untreated Graves' patients we observed an increase in the percentage of CD19+ (p<0.007, p<0.003), CD4+ (p<0.004, p<0.017), CD4+CD45RO+ (p<0.04, NS), CD4/CD8 ratio (p<0.002, p<0.001) and a decrease in the percentage of CD8+ (p<0.02, p<0.02), CD4+CD45RA+ (p<0.04, p<0.03) cells in comparison to the healthy control subjects and euthyroid Graves' patients. These abnormalities were absent in children with non-toxic nodular goiter. In addition, the levels of CD3+, CD4+CD8+, CD8+CD45RO+ T cells and CD8 lymphocytes co-expressing CD45RA and CD45RO antigens were similar in all groups and no statistically significant differences were found in comparison to the healthy controls. In the untreated Graves' patients we found a positive correlation between serum levels of fT4 and fT3 and the percentage of CD19+ lymphocytes (r = 0.45, p<0.01, r = 0.37, p<0.04), between serum level of fT4 and the percentage of CD4CD45RO (r = 0.4, p<0.02) lymphocytes and between concentration of TRAb and CD4+ (r = 0.38, p <0.04) and CD19+ (r = 0.39, p<0.016) cells. Statistically significant negative correlations existed between TRAb, TPO-Ab or TG-Ab concentration in blood serum and the percentage of CD8+ lymphocytes (r = -0.55, p<0.002; r = -0.41, p<0.02; r = -0.51, p<0.004), and between fT4 concentration and the percentage of CD8+ (r = -0.39, p<0.02) lymphocytes. No such correlation was detected in patients with non-toxic nodular goiter. We conclude that the abnormal distribution of B lymphocytes, memory and naive T cell subsets in the peripheral blood in children and adolescents with untreated Graves' disease suggests their role in the development of autoimmunity. The normalization in the percentage of these immune cells after thyrostatic treatment in comparison to newly diagnosed patients confirms the immunomodulatory effect of methimazole therapy.  相似文献   
170.
The purpose of this study was to characterize basolateral anion channels in Calu-3 and normal human bronchial epithelial cells, and their role in anion secretion. Patch clamp studies identified an outwardly rectifying Cl- channel (ORCC), which could be activated by the adenosine receptor agonist 5'-(N-ethylcarboxamido)adenosine (NECA). Short-circuit current measurements revealed that NECA activates a basolateral, but not an apical, anion conductance sensitive to 4,4'-diisothiocyanatostilbene-2, 2'-disulfonic acid, and to 9-anthracenecarboxylic acid, but not to 4,4'-dinitrostilbene-2,2'-disulfonic acid. Apical membrane permeabilization studies confirmed the presence of basolateral anion channels, established their halide permeability sequence (Cl- >/= Br- > I-), and demonstrated their outwardly rectifying nature. Experiments using H-89, forskolin, and Ht31 demonstrated that adenosine receptor dependent activation of basolateral ORCC was cAMP- and potentially A-kinase anchoring protein-dependent. Neither BAPTA-AM treatment nor basolateral Ca2+ removal had any effect on the activation of these channels. Anion replacement and 36Cl- flux studies show that Calu-3 cells primarily secrete HCO3- when stimulated with NECA, and that Cl- secretion can be stimulated by blocking basolateral ORCC, whereas normal human bronchial epithelial cells exclusively secrete Cl- under all conditions studied. We propose a novel model of anion secretion in which ORCC recycles Cl- across the basolateral membrane, allowing preferential HCO3- secretion.  相似文献   
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