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51.
该文旨在介绍Beth Israel医疗中心采用大剂量术中放疗(HDR-IORT)治疗复发头颈癌的经验。对2001-2010年间头颈癌局部复发接受大剂量HDR-IORT的患者进行回顾分析。结果,76例患者的87个部位在肿瘤切除后接受了治疗。术后2年控制率为62%。平均总生存期为19个月,其中42%的患  相似文献   
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Purpose

To investigate renal ischemia injury during renal hilar clamping (artery alone versus clamping artery/vein together) by evaluating ischemic damage via two different modalities in animal models—near-infrared tissue oximetry and 8-isoprostane levels.

Methods

Near-infrared renal oximetry measurements of Yorkshire swines (n = 4; 8 renal units) subject to hilar clamping were obtained at baseline, during warm ischemia (15- and 30-min trials) and after unclamping. Quantitation of 8-isoprostane levels is the second technique of quantitating interstitial fluid collected from a dialysis catheter placed through renal parenchyma of male Sprague–Dawley rats (n = 50) subject to hilar clamping during preclamp, clamp (either 15 or 30 min of hilum clamping), and post-clamp.

Results

N ear-infrared tissue oximetry. In the 15-min trial, oxygen saturation decreased 6× faster with artery alone compared to artery/vein clamped together. In the 30-min trial, the decrease was 5× faster. Recovery of oxygen saturation with only artery clamped occurred more than 2× faster in the 15- and 30-min periods. Isoprostane. For 15-min clamp times, 8-isoprostane levels in the artery alone group demonstrated a 1.54 decrease in the artery clamped alone group (p = 0.006) versus artery/vein together: preclamp (11.47 and 11.63 pg/mL/g), clamp (14.61 and 17.70 pg/mL/g), and post-clamp (14.26 and 22.04 pg/mL/g).

Conclusions

Renal ischemia injury from clamping the renal artery alone was significantly less than clamping artery/vein together demonstrated in two different techniques. Recovery of oxygen saturation was twofold faster, and mean post-clamp 8-isoprostane levels demonstrated a 1.54-fold decrease with clamping renal artery alone compared to clamping artery/vein together.  相似文献   
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ObjectiveOT was reported to be a direct regulator of bone mass in young rodents, and this anabolic effect on bone is a peripheral action of OT. The goal of this study was to investigate the peripheral action of oxytocin (OT) in the alveolar healing process in old female rats.Materials and methodsFemales Wistar rats (24-month-old) in permanent diestrus phase, received two ip (12 h apart) injections of saline (NaCl 0.15 M – control group) or OT (45 μg/rat – treated group). Seven days later, the right maxillary incisor was extracted and analyses were performed up to 28 days of the alveolar healing process (35 days after saline or OT administration).ResultsCalcium and phosphorus plasma concentrations did not differ between the groups. The plasma biochemical bone formations markers, alkaline phosphatase (ALP) and osteocalcin were significantly higher in the treated group. Histomorphometric analyses confirmed bone formation as the treated group presented the highest mean value of post-extraction bone formation. Tartrate-resistant acid phosphatase (TRAP) was significantly reduced in the treated group indicating an anti-resorptive effect of OT. Immunohistochemistry reactions performed in order to identify the presence of osteocalcin and TRAP in the bone cells of the dental socket confirmed these outcomes.ConclusionsOT was found to promote bone formation and to inhibit bone resorption in old acyclic female rats during the alveolar healing process.  相似文献   
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Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)..  相似文献   
58.
AIM: To assess the accuracy of a model in diagnosing severe fibrosis/cirrhosis in chronic hepatitis C virus (HCV) infection. METHODS: The model, based on the sequential combination of the Bonacini score (BS: ALT/AST ratio, platelet count and INR) and ultrasonography liver surface characteristics, was applied to 176 patients with chronic HCV infection. Assuming a pre-test probability of 35%, the model defined four levels of post-test probability of severe fibrosis/cirrhosis: <10% (low), 10-74% (not diagnostic), 75-90% (high) and >90% (almost absolute). The predicted probabilities were compared with the observed patients' distribution according to the histology (METAVIR). RESULTS: Severe fibrosis/cirrhosis was found in 67 patients (38%). The model discriminated patients in three comparable groups: 34% with a very high (>90%) or low (<10%) probability of severe fibrosis, 33% with a probability ranging from 75% to 90%, and 33% with an uncertain diagnosis (i.e., a probability ranging from 10% to 74%). The observed frequency of severe fibrosis/ cirrhosis was within the predefined ranges. CONCLUSION: The model can correctly identify 67% of patients with a high (>75%) or low (<10%) probability of cirrhosis, leaving only 33% of the patients still requiring liver biopsy.  相似文献   
59.
The total surgical experience of a supraregional paediatric cardiology unit over a nine year period (January 1980 to December 1988) was reviewed to assess the effect of the introduction of the full range of ultrasound techniques. A total of 1517 patients underwent cardiac surgery (955 cardiopulmonary bypass, 562 closed procedures). Of these, 485 patients (32%) did not undergo cardiac catheterisation before operation: 217 bypass (23% of all procedures under cardiopulmonary bypass) and 268 closed procedures (48%). The overall ratio of catheterisations to operations for patients undergoing palliative or corrective surgery fell from 0.97 (1980) to 0.38 (1988). The patients were classified as (a) neonates (0-28 days), (b) infants (one to 12 months), and (c) children (one to 14 years). The main impact of non-invasive surgical referral was in neonates (total catheter:operation ratio 0.38; neonates 0.2 for 1988). The surgical population was further divided according to the principal echocardiographic technique available: (a) 1980-4 cross sectional imaging; (b) 1985-6; imaging plus spectral Doppler ultrasound; (c) 1987-8; imaging plus spectral Doppler ultrasound and colour flow mapping. A fall in the catheter:operation ratio for all age groups was most pronounced in the last four years. This reflects increased familiarity and surgical confidence with non-invasive diagnostic assessment. The introduction of each new echocardiographic technique was associated with a significant fall in the total catheter:operation ratio compared with the preceding period. Six incorrect ultrasound diagnoses were made during the entire period; one of these patients died in the early postoperative period. The integration of Doppler ultrasound with cross sectional imaging has made non-invasive assessment an increasingly practical alternative to preoperative cardiac catheterization.  相似文献   
60.
In primary systemic amyloidosis, small numbers of bone marrow plasma cells secrete monoclonal light chains that form extracellular fibrils (amyloid) in various organs. Evidence limited to a few cases suggests that rare clonal elements can also be found in the peripheral blood (PB), and this may be relevant in PB stem cell autotransplantation. Since up to 40% of amyloid clones do not synthesize heavy chains, in order to detect tumor cells with high specificity and sensitivity we developed a seminested allele-specific oligonucleotide polymerase chain reaction for tumor light chains. Clone-related sequences were detected in DNA and/or cDNA from the PB cells of eight of 10 patients at diagnosis and from apheretic collections of three of four cases undergoing PB progenitor autotransplantation. Since there are experimental data suggesting that circulating tumor cells may be involved in the growth of the amyloidogenic clone and may be chemoresistant, these findings are relevant to the use of leukapheresis purging strategies for PB progenitor autotransplantation in amyloidosis.  相似文献   
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