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71.
In the present study, we have synthesized mixed cuprous/copper oxide nanosuspensions by metallosurfactant based microemulsion technique. Three metallosurfactants were synthesized which includes two non-ionic double chained metallosurfactants with C12, C16 chains with coordinated copper i.e. Cudda and Cuhexa, respectively. Another cationic double chained metallosurfactant with loosely bound metal (Cuctac) was also prepared. The prepared metallocomplexes were characterized using FTIR, elemental analysis, and NMR. The effect of the position of metallosurfactant in microemulsion on the fabrication and properties of nanosuspensions was elucidated. In this method, no external reducing agent and capping agent were added and tween 80 acted both as reducing and stabilizing agent for the nanoparticles. The synthesized nanoparticles were characterized and it was observed that mixed copper and cuprous oxide particles are present in colloidal suspension for all the three studied metallosurfactants. The kinetics of formation of mixed copper/cuprous oxide nanosuspensions (Ns) and their stability was estimated using Uv-visible spectroscopy. Further, the binding and interactions of copper nanosuspensions with calf Thymus DNA (CT-DNA) were assessed using Uv–vis spectroscopy, circular dichroism and gel electrophoresis. Additionally, the antioxidant activity of the Cu Ns was checked using DPPH assay. The role of positive charge on nanoparticles as evaluated from Zeta potential was responsible for DNA affinity. The DNA conformational changes in the presence of nanosuspensions and relevant scavengers were investigated. Further, the anti-proliferative activity of copper Ns was assessed using HeLa cells and Cuhexa derived Ns were proved to be active with highest activity at a low concentration and were nontoxic towards normal cell lines. In summary, this work demonstrates a softer approach for the synthesis of copper nanosuspensions with a size range of 2–5?nm and evaluated the role of type and structure of metallosurfactant on size, stability of particles and anti-proliferative activity.  相似文献   
72.
The purpose of this paper was to report an unusual case of multirooted permanent maxillary canine. A 16-year-old female patient presented with pain and swelling related to the upper right permanent canine. Radiographic examination revealed a multirooted permanent maxillary canine--an unusual finding. Endodontic treatment was performed after amputation of 2 extra roots, and then the tooth was intentionally reimplanted. The prevalence of birooted permanent mandibular canines in the Japanese population has been reported, but the prevalence of this 3-rooted maxillary canine is still unknown. This report also states the potential etiological factors, effects on the developing dentition, and various treatment options for the multirooted maxillary permanent canine.  相似文献   
73.
Cutibacterium acnes (C. acnes) is a significant insidious pathogen for postoperative infections in shoulder surgery. Studies have demonstrated that certain topical antibiotic powders used have the potential for chondrotoxicity. Benzylpenicillin, commonly referred to as Penicillin G (Pen G) has the lowest minimum inhibitory concentration (MIC) for C. acnes. There is no research regarding the topical application of Pen G during shoulder surgery, nor has its chondrocyte toxicity been previously investigated. This study sought to characterize the in vitro chondrocyte toxicity of Pen G. Culture-derived bovine chondrocytes were exposed to serial Pen G concentrations and compared with a positive and negative control. A negative control of growth medium and positive control of 1% Triton solution. The chondrocyte viability was assessed via spectrophotometer absorbance. The treatment groups were analyzed using one-way repeated measures analysis of variance and Pearson's correlation analysis. The chondrocyte viability was significantly higher for all Pen G concentrations as compared with the positive control (p < 0.001). All concentrations of Pen G exhibited continued chondrocyte metabolic activity over time. Analysis of variance, independent of time, demonstrated no significant decrease in chondrocyte viability for Pen G concentrations ≤6.25 mg/ml, as compared with the negative control (p > 0.05). Pen G demonstrated a significant negative correlation with its concentration and absorbance (r = 0.371, p < 0.001), however, concentrations ≤6.25 mg/ml did not demonstrate a significant decrease in chondrocyte viability (p = 0.063). Pen G in concentrations appropriate for C. acnes is not significantly chondrotoxic and may be safe for intrawound application. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:726-730, 2020  相似文献   
74.
The study consisted of application of anti-ubiquitin antibodies (Abs)-coated iron oxide-nanoparticles (IONPs) for minimisation of oxidative stress to contemporary live spermatozoa from the raw semen. Round-shaped IONPs (12.09 ± 0.91 nm) after two-stage functionalisation (silanisation and pegylation) were conjugated with Abs. Four aliquots from each of the 24 ejaculates (4 buffalo bulls) formed Control (Group I) and treatment (II, III and IV) groups; each containing 150 ± 25 million dead/damaged spermatozoa. IONPs-Abs complex were added at ratio of 1:1 (0.5 µg/ml), 1:2 (1.0 µg/ml) and 1:4 (2.0 µg/ml), respectively, in Groups II, III and IV. The semen quality parameters showed improvement at lag-stage (post-nano-purification before processing for cryopreservation). The mean post-thaw motility (%) in Group IV was found to be greater (p < .05) than Group I. Moreover, the overall DNA integrity (%) at post-thaw stage was improved in the nano-purified semen samples. The value of malondialdehyde was greater (p < .001) in Group I than Groups II, III and IV. The mean total antioxidant capacity and superoxide dismutase (U/mg protein) activity values in Group IV was greater (p < .05) than Group I. The study results show that IONPs conjugated with anti-ubiquitin Abs at 2.0 µg/ml can be an effective dose for depletion of dead/damaged spermatozoa from buffalo ejaculates to minimise oxidative stress.  相似文献   
75.
76.

Purpose

The prediction of number of casts in the Ponseti method has always remained a subject of interest. We investigated the correlation of the number of casts before tenotomy with the age and initial Pirani score in Ponseti treatment of club foot.

Methods

Inclusion criteria were idiopathic clubfeet corrected by Ponseti method requiring tenotomy for equinus correction in children up to ten years of age. Defaulters (noncompliance with serial casting schedule), children with postural, non idiopathic, previously surgically treated, recurrent clubfoot and clubfoot not requiring tenotomy were not included in this study. Further, children who did not require tenotomy were also excluded. ANOVA regression analysis was used for finding correlation between initial Pirani score, age in months and number of corrective casts prior to tenotomy.

Results

There were a total of 297 children (442 feet) in the study. The average age of the child at presentation was 10.3 months and the average initial Pirani score was 4.8. The average number of corrective casts was seven per child (range, two to18). The regression analysis showed both Pirani and age had positive correlation with number of casts, although weak (r2 = 0.05–0.20). The initial Pirani scoring correlated ten times more than age (in months) to the number of casts.

Conclusion

The number of casts for correction in idiopathic clubfoot, although variable, is influenced by both initial Pirani score and age.  相似文献   
77.

Background

The benefit of cytoreductive nephrectomy (CN) for overall survival (OS) is unclear in patients with synchronous metastatic renal cell carcinoma (mRCC) in the era of targeted therapy.

Objective

To determine OS benefit of CN compared with no CN in mRCC patients treated with targeted therapies.

Design, setting, and participants

Retrospective data from patients with synchronous mRCC (n = 1658) from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) were used to compare 982 mRCC patients who had a CN with 676 mRCC patients who did not.

Outcome measurements and statistical analysis

OS was compared and hazard ratios (HRs) adjusted for IMDC poor prognostic criteria.

Results and limitations

Patients who had CN had better IMDC prognostic profiles versus those without (favorable, intermediate, or poor in 9%, 63%, and 28% vs 1%, 45%, and 54%, respectively). The median OS of patients with CN versus without CN was 20.6 versus 9.5 mo (p < 0.0001). When adjusted for IMDC criteria to correct for imbalances, the HR of death was 0.60 (95% confidence interval, 0.52–0.69; p < 0.0001). Patients estimated to survive <12 mo may receive marginal benefit from CN. Patients who have four or more of the IMDC prognostic criteria did not benefit from CN. Data were collected retrospectively.

Conclusions

CN is beneficial in synchronous mRCC patients treated with targeted therapy, even after adjusting for prognostic factors. Patients with estimated survival times <12 mo or four or more IMDC prognostic factors may not benefit from CN. This information may aid in patient selection as we await results from randomized controlled trials.

Patient summary

We looked at the survival outcomes of metastatic renal cell carcinoma patients who did or did not have the primary tumor removed. We found that most patients benefited from tumor removal, except for those with four or more IMDC risk factors.  相似文献   
78.
The current work focuses on the in vivo performance of a newly developed injectable composite graft in infected full‐thickness wounds. The composite graft was composed of bioactive porous Poly dl‐lactide‐co‐glycolide scaffolds, antibiotic gentamicin, and crosslinked gelatin as carrier gel. Treated infected wounds exhibited a faster wound closure, rapid weight gain, lower neutrophil count, higher breaking strength, and 100 times lesser microbial count (102 colony forming units/g in infected treated vs. 104 colony forming units/g in infected control group) in comparison with infected control group 28 days post treatment. During healing, collagen production was more in the treated groups at day 7 than controls and thereafter gradually reduced to normal levels. Histology revealed a mature scar tissue formation, fibroblast proliferation, epidermal resurfacing, and collagen deposition in reticular alignment similar to normal healthy skin in treated wounds. Further, the plasma concentration of gentamicin was 35–45 μg/mL during the initial 12 hours and reduced to 1 μg/mL in 24 hours, which indicated safe levels of the antibiotic drug during healing. These results clearly indicate a faster, infection‐free, and safe after treatment with the developed graft.  相似文献   
79.
80.
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