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131.
PURPOSE: The aim of the study was to evaluate factors possibly effecting the posterior capsule opacification (PCO), after extra-capsular cataract extraction with the posterior chamber intra-ocular lens (IOL) implantation. Age of patients, refractive errors, technique of cataract extraction, intra- and postoperative complications and coexisting diseases were taken into consideration. In 1992-98 posterior laser Nd:YAG capsulotomy was performed in 222 eyes of 222 patients (134 women and 88 men) previously operated in 1st and IInd Eye Clinic. PCO occurred in 5.8% patients, who underwent cataract extraction in this period, in 5.7% patients operated with phacoemulsification method and in 5.8% patients where extra-capsular cataract extraction with nucleus expulsion was performed. PCO was diagnosed in 12.7% patients at the age below 30, in 17% aged 31-40, in 7.8% aged 41-55 and in 5.1% patients older than 55 years. Among the patients, who developed PCO, in 6.3% myopia was present, in 8% primary open angle glaucoma, 16.6% were treated for diabetes mellitus. In 7.6% eyes the intra-operative cortical clean up was not efficient. CONCLUSION: PCO occurred in young patients (under 40) twice as often as in the other groups of age. Technique of cataract extraction had an influence on the incidence of PCO as well.  相似文献   
132.
PURPOSE: Intra-operative and postoperative complications of the first 50 phacoemulsifications were evaluated. The procedures were performed by one, skilled at ECCE surgeon. The phaco-chop technique was carried out in all cases with use of anterior chamber maintainer (ACM). MATERIAL AND METHODS: Eyes for surgery met the requirements: normal comea, presence of red reflex from the fundus and correct lens position. The patients were divided into 2 groups: I group--25 eyes had first surgery, II group--25 eyes had second surgery. On the first day after surgery complications and uncorrected acuity were evaluated. RESULTS: 50 eyes of 48 patients underwent operation. The mean age was 69.4 years 5% eyes had previous surgical record: 4--underwent trabeculectomy, 1--pars plana vitrectomy. The 12 intra-operative complications appeared in 10 eyes (20%): posterior capsule rupture without vitreous loss in 4% and 10% with vitreous loss, Descemet membrane detachment in 4%, iris dialysis in 2%, and persistent iris damage without sphincter disruption in 4%. The 16 postoperative complications concerned 10 eyes (20%): corneal oedema in 20%, transient intra-ocular pressure raise in 8%, hyphaema in 2%, and fibrin exudation in 2%. The majority of complications concerned the I group of eyes. The uncorrected visual acuity was 0.5 or better in 80% of eyes, on the first day after the operation. CONCLUSIONS: The use of ACM made the first steps in phacoemulsification rate during the learning course.  相似文献   
133.
PURPOSE: To evaluate the results of pars plana vitrectomy and membrane stripping for idiopathic and secondary preretinal macular membrane (PMM). MATERIAL AND METHODS: Twenty one consecutive subjects (21 eyes) ranging in age from 40 to 78 (mean 66.9) with PMM underwent vitrectomy and membrane peeling. 17 cases had membranes that were considered idiopathic, and 4 cases were associated with other disorders: 3 occurred after successful retinal reattachment surgery, 1--after laserotherapy in the course of diabetic retinopathy. Visual acuity (VA), Amsler grid, and postoperative complications were assessed. The follow-up was 1 to 22 months, mean 5.7. RESULTS: Visual acuity improved postoperatively in 15 eyes (71.4%), at least two lines on the Snellen chart in 8 eyes (38.1%), entirely in patients with idiopathic PMM. It remained unchanged in 3 eyes (14.3%) and deteriorated in 3 eyes (14.3%). Eyes with transparent membrane showed greater visual improvement than opaque ones. The preoperative Amsler test was positive in 15 patients (71.4%), postoperatively--in 4 cases (19%). 2 idiopathic cases with VA of 0.7 showed postoperatively VA of 1.0. Complications included retinal detachment in 2 eyes (1 in idiopathic and 1 in secondary PMM), and development of nuclear sclerotic cataract in 2 eyes. At 6 months of follow-up, a residual membrane formation in 1 cases appeared. Macular pseudohole was observed in 1 eye with no impact on visual results. CONCLUSIONS: 1. Vitrectomy with membrane peeling for preretinal macular membrane provides improvement in visual acuity and reduces metamorphopsia 2. Thin, cellophane-like appearance of the membrane gives a better prognosis of visual function improvement.  相似文献   
134.
PURPOSE: To analyze the effect of different concentrations and application intervals of indocyanine green (ICG) on the retina in an experimental setting of macular surgery. METHODS: Twenty-one porcine eyes were used within 5 hours after enucleation. The eyes were hemisected and the vitreous removed. Different doses of ICG (up to 1 mg) were applied over the trephined macula, and the remainder of the eyecup was filled with a balanced salt solution (BSS). Both the ICG solution and the BSS were drained after 30 or 60 seconds and the complete eyecup irrigated and filled with fresh BSS. The posterior pole was then illuminated with a standard surgical light pipe and light source at maximum power for 3 minutes. Both the ICG-treated retina and the nontreated surrounding retina were processed for histology. RESULTS: Exposure of the retina at different concentrations of ICG either for 30 or 60 seconds, followed by illumination, caused no histologically detectable damage compared with the controls. No microarchitectural disorganization or cellular disruption was detected. The vitreoretinal interface seemed unaffected. CONCLUSIONS: Previously described severe damage to the inner retina of human donor eyes could not be found with even higher doses of ICG in this porcine model. Although differences within the species may contribute to these contradictory results, it is conceivable that the postmortem time and the vitality of the tissue influence the outcome in this ex vivo system.  相似文献   
135.
The surface expression of CD117 antigen (c-kit) on plasma cells from 158 multiple myeloma (MM), 12 plasma cell leukemia (PCL), 7 MGUS, 7 IgM lymphoplasmacytic lymphoma patients and 10 healthy subjects has been analyzed by flow cytometry using triple staining with the monoclonal antibodies CD138, CD117 and CD38. The antigen expression intensity was calculated as relative fluorescence intensity (RFI) and for direct quantitative analysis the QuantiBRITE test (Becton Dickinson) was applied. Antibody bounding capacity (ABC) was calculated using QuantiCALC software. CD117 antigen was present in 49/158 MM, 5/12 PCL and 5/7 MGUS patients. The RFI values ranged from 0.2 to 20.2 in particular MM patients (mean: 11.0 ± 5.3; median 11.5) while the number of CD117 binding sites (ABC) on MM plasma cells ranged from 637 to 6217 (mean: 3029 ± 1568; median 2946) (r = 0.8328). In responsive to chemotherapy c-kit positive MM patients the percentage of CD117 +  plasma cells in the bone marrow decreased significantly while in c-kit negative MM patients the percentage of CD117 +  cells in bone marrow did not change and remained in the normal limits. When comparing the clinical and biological disease characteristics (monoclonal protein isotype, albumin, β2-microglobulin, lactate dehydrogenase, stage of disease, response to chemotherapy, survival time) of c-kit positive and c-kit negative cases, no significant differences were found. In CD117 positive PCL cases expression of CD117 was detected in bone marrow plasma cells as well as in peripheral blood plasma cells. Normal plasma cells and those in IgM lymphoplasmacytic lymphoma did not show reactivity for the CD117 antigen. We conclude that it may be rationale to consider usefulness of therapy with tyrosine kinase inhibitors in the management of c-kit positive plasma cell proliferations. In one third of MM and PCL patients c-kit antigen could be considered as a "tumor associated marker" and together with CD38 and CD138 it may be of value for the identification of the malignant clone in minimal residual disease as it was first suggested by Spanish authors.  相似文献   
136.
Granulocyte-colony stimulating factor (G-CSF), in addition to myeloid and stem cells, mobilizes a large number of lymphoid cells. We examined which lymphoid populations were mobilized in 21 consecutive donors of peripheral blood stem cells (PBSC) and whether the differences in mobilization could affect the incidence of acute and chronic GvHD in respective HLA-identical recipients. G-CSF administration induced significant increases of donor B (CD3CD19+) lymphocytes and slight increases of T (CD3+) and cytotoxic (CD16+CD56+) NK cells. The number of extrathymic cells (CD3+ cells with NK markers, or CD7+) remained unchanged except for an increase of CD3+CD57+CD8+ cells. Donors of patients without subsequent grade II–IV acute GvHD compared to donors of patients who developed significant acute GvHD were found to have in peripheral blood stable numbers of CD3+CD4+ cells producing IL2, with a concomitant increased number of CD3+CD4low+CD25+ T regulatory cells and decreased NK-mediated cytotoxicity, together with a higher number of suppressive extrathymic CD57+CD3+ cells in the blood and G-PBMC grafts. Increasing numbers of activated T and NK cells in the blood were associated with the development of chronic GvHD. We suggest that differences in steady-state levels and kinetics of G-CSF induced mobilization of donor lymphoid cells may in addition to other well-known factors affect the incidence of GvHD in HLA-identical recipients. However, owing to the small number of donor-recipient pairs studied, our results must be verified in a larger group of patients. Both authors contributed equally to this study.  相似文献   
137.
Despite the widespread use of exogenous surfactant, acute and chronic lung injury continues to be a major cause of morbidity in preterm infants. CC10 is a protein produced by Clara cells that inhibits phospholipase A2 and has anti-inflammatory and antifibrotic properties. We studied whether intratracheal (IT) recombinant human Clara cell protein (rhCC10) could safely minimize lung injury in a newborn piglet model of acute lung injury. Twenty-nine newborn piglets were given Survanta and then ventilated for 48 h receiving the following: room air (group 1); 100% O2 (group 2); or 100% O2 and 25, 5, or 1 mg/kg (groups 3, 4, and 5, respectively) of IT rhCC10 (diluted to 2 mL/kg with saline) at time 0. Laboratory studies, oxygen ratios, static pressure-volume curves, bronchoalveolar lavage (for inflammatory markers), and histologic analyses were performed over the 48-h study period. Pulmonary compliance and oxygenation were significantly improved in animals receiving 5 mg/kg IT rhCC10 compared with room air and 100% O2 controls (p < 0.004 and p < 0.05, respectively, ANOVA). Reductions in inflammatory markers were seen in animals receiving rhCC10, although changes did not reach statistical significance. No significant toxicity was noted. rhCC10 appeared safe and improved pulmonary function in this newborn piglet model of hyperoxic lung injury. We speculate that rhCC10 may represent a promising therapy for the prevention of lung injury in preterm infants.  相似文献   
138.
We report here on the exuberant glial reaction in the optic nerves affected by prion diseases. Optic nerves from CJD- and GSS-, and scrapie-infected mice and hamsters showed severe pathology. These lesions were qualitatively indistinguishable from each other but were more intense in the Fujisaki model than in the hamsters inoculated with Echigo-1. Exuberant cellular reaction comprised of macrophages containing numerous mitochondria, abundant rough endoplasmic reticulum, and secondary lysosomes filled with digested myelin debris, electron-dense material and occasionally, entire myelin-bound vacuoles were readily observed in both models. Macrophages actively digesting myelin fragments and containing lyre-like bodies and paracrystalline inclusions were frequently noted. Some macrophages extended long filopodia to form labyrinth-like structures, and within a few macrophages, concentric arrays of cisterns and channels sequestrated part of the cytoplasm. An analogous network of narrow cisterns was seen to surround whole segments of the myelinated fibers.  相似文献   
139.
Many recent studies indicate that long term use of contraceptives is a strong risk factor in the development of cervical cancer. Steroid hormones, in persistent papilloma virus infection act on various levels, one of them is enhancing transforming activity of the virus. The aim of the study was to estimate if physiological concentrations of 17 beta-estradiol could influence expression of viral transforming genes. HeLa cell lines were incubated with three different physiological concentrations and and on the third day of incubation the level of E6 gene expression was determined. Results show no differences in expression between the control culter, and cultures incubated with physiological concentrations. It indicates that normal levels of 17 beta-estradiol don't play role in transforming process but it also shows need to analyse higher levels of hormones by quantitative analyses in prospective studies.  相似文献   
140.
We determined the pattern of cross-reactivity of a panel of anti-streptokinase (SK) monoclonal antibodies (mAbs) with SK variants in order to map the antigenic and functional epitope of SK. Comparison of the pattern of cross-reactivity of the anti-SK mAb A4.3 with SK variants and sequence alignments of SK variants and native (n) SK suggested that mutation of Ser 138 to Lys results in loss of binding of mAb A4.3 to SK variants. However, this mutation does not affect formation of activator complex by these proteins. The epitope specificity of the mAb A4.3 was further confirmed by mutating Ser 138 to Lys in n SK. Monoclonal Ab A4.3 did not bind to mutant SK (Ser138Lys). Activator activity of mutant SK (Ser138Lys) was indistinguishable from that of n SK and recombinant n SK. Since addition of A4.3 mAb to an equimolar mixture of SK and human plasminogen inhibits activator complex formation, the sequences spanning position 138 are likely important for formation of streptokinase-plasminogen activator complex or processing of the plasminogen substrate.  相似文献   
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