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81.

Purpose

The purpose of this work is to explore audiometry following cochlear implantation (CI) in patients with enlarged vestibular aqueduct (EVA) and to investigate the effects of inner ear morphological variation on post CI audiometry.

Methods

This was a retrospective review of both natural and cochlear-implant-aided audiometry results, using all available measurements in a mixed-effects model accounting for longitudinal change and the grouping structure of ears. Patients who visited our tertiary academic medical center between 2000 and 2016 were identified as having EVA according to Cincinnati criteria on radiological examination; patients eligible for CI were then selected for analysis.

Results

Multivariable modeling showed a statistically significant hearing improvement in ears with EVA undergoing CI with regards to pure tone average (?64.0?dB, p?<?0.0001), speech reception threshold (?57.90?dB, p?<?0.0001), and word score (34.8%, p?>?0.0001). Vestibular aqueduct midpoint size and the presence of incomplete partition type II (IP II) did not have significant independent associations with audiometric findings. However, multivariable modeling revealed a statistically significant interaction between IP II and CI such that IP II ears demonstrated a decrease in WS improvement of 30.2% (p?=?0.0059) compared to non-IP II ears receiving CI.

Conclusion

There is a statistically significant audiometric benefit to ears with EVA receiving CI. Morphology, specifically the presence of IP II, may hinder CI benefit in terms of word score however this finding needs clinical validation. This data improves personalization of surgical counseling and planning for patients with EVA considering CI.  相似文献   
82.
Phylogenetic analysis of influenza viruses collected during December 2009–February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. Many amino acid signatures observed were characteristic of human isolates; hence, their circulation could enhance inter- or intrasubtypic reassortment.  相似文献   
83.
84.
This work evaluates the antifungal activity of two essential oil components against 28 clinical isolates (17 sensitive, 11 resistant) and 3 standard laboratory strains of Candida. Growth of the organisms was significantly effected in both solid and liquid media at different test compound concentrations. The minimum inhibitory concentrations (MICs) of Isoeugenol (compound 1) against 31 strains of Candida ranged 100–250 μg/ml and those of o ‐methoxy cinnamaldehyde (compound 2) ranged 200–500 μg/ml, respectively. Insight studies to mechanism suggested that these compounds exert antifungal activity by targeting H+‐ATPase located in the membranes of pathogenic Candida species. At their respective MIC90 average inhibition of H+‐efflux for standard, clinical and resistant isolates caused by compound 1 and compound 2 was 70%, 74%, 82% and 42%, 42% and 43%. Respective inhibition of H+‐efflux by fluconazole (5 μg/ml) was 94%, 92% and 10%. Inhibition of H+‐ATPase leads to intracellular acidification and cell death. SEM analysis of Candida cells showed cell membrane breakage and alterations in morphology. Haemolytic activity on human erythrocytes was studied to exclude the possibility of further associated cytotoxicity. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
85.
Poly(caprolactone) (PCL) has been frequently considered for bone tissue engineering because of its excellent biocompatibility. A drawback, however, of PCL is its inadequate mechanical strength for bone tissue engineering and its inadequate bioactivity to promote bone tissue regeneration from mesenchymal stem cells. To correct this deficiency, this work investigates the addition of nanoparticles of silica (nSiO(2)) to the scaffold to take advantage of the known bioactivity of silica as an osteogenic material and also to improve the mechanical properties through nanoscale reinforcement of the PCL fibers. The nanocomposite scaffolds and the pristine PCL scaffolds were evaluated physicochemically, mechanically, and biologically in the presence of human mesenchymal stem cells (hMSCs). The results indicated that, when the nanoparticles of size approximately 10?nm (concentrations of 0.5% and 1% w/v) were embedded within, or attached to, the PCL nanofibers, there was a substantial increase in scaffold strength, protein adsorption, and osteogenic differentiation of hMSCs. These nSiO(2) nanoparticles, when directly added to the cells evidently pointed to ingestion of these particles by the cells followed by cell death. The polymer nanofibers appeared to protect the cells by preventing ingestion of the silica nanoparticles, while at the same time adequately exposing them on fiber surfaces for their desired bioactivity.  相似文献   
86.
Human immunodeficiency virus (HIV) infection is a major health burden across the world which leads to the development of acquired immune deficiency syndrome (AIDS). This review article discusses the prevalence of HIV, its major routes of transmission, natural immunity, and evasion from the host immune system. HIV is mostly prevalent in Sub‐Saharan Africa and low income countries. It is mostly transmitted by sharing syringe needles, blood transfusion, and sexual routes. The host immune system is categorized into three main types; the innate, the adaptive, and the intrinsic immune system. Regarding the innate immune system against HIV, the key players are mucosal membrane, dendritic cells (DCs), complement system, interferon, and host Micro RNAs. The major components of the adaptive immune system exploited by HIV are T cells mainly CD4+ T cells and B cells. The intrinsic immune system confronted by HIV involves (apolipoprotein B mRNA‐editing enzyme, catalytic polypeptide‐like 3G) APOBEC3G, tripartite motif 5‐α (TRIM5a), terherin, and (SAM‐domain HD‐domain containing protein) SAMHD1. HIV‐1 efficiently interacts with the host immune system, exploits the host machinery, successfully replicates and transmits from one cell to another. Further research is required to explore evasion strategies of HIV to develop novel therapeutic approaches against HIV.  相似文献   
87.
The study was designed to evaluate the role of antioxidant defense system in the etiology of psoriasis, a chronic skin disorder of complex etiology and pathology. Hospital-based case–control study was carried out in major referral hospital in Kashmir, North India. Cases (N?=?40) were composed of patients with psoriasis vulgaris, and controls (N?=?20) were healthy volunteers. Study included estimation in plasma of both patients and controls of glutathione (GSH) levels, superoxide dismutase (SOD) activity, and total antioxidant potential (AOP) as indices of antioxidant defense system and malondialdehyde (MDA) as a measure of lipid peroxidation (LP), an indicator of oxidative stress. The GSH levels, SOD activity, AOP, and malondialdehyde levels in plasma of psoriasis patients were 2.58?±?0.22 μM/l, 5.24?±?0.69 U/ml, 0.020?±?.011?nmol?1/ml?h, and 0.88?±?0.20 nmol/ml and were 4.76?±?0.52 μM/l, 4.14?±?0.56U/ml, 0.042?±?0.018 nmol?1/ml?h, and 0.53?±?0.16 nmol/ml in healthy voluntary controls, respectively. A significant decrease in GSH levels (p?<?0.005) and AOP (p?<?0.005) and significant increase in SOD activity (p?<?0.01) MDA levels (p?<?0.005) as an indicator of LP was observed.  相似文献   
88.
Forty patients with an average age of 26.5 years were treated for symptomatic low-grade isthmic spondylolisthesis with in situ instrumented posterolateral fusion. All patients had failed previous conservative treatment. Average follow-up was 42.2 months (range: 30-62 months). Low-back pain resolved in 70% of the patients, whereas 65% of those with radicular pain reported complete resolution of the symptoms. At the final follow-up 82.5% of the patients had improvement in their function. Solid fusion was achieved in 70% of the patients. It was uncertain in 10% and a fusion failure was seen in 20%. The anterior slippage as measured by the Taillard method was 31.55% and an average 35% correction was seen after surgery. However, an average 10% loss of correction was seen at the final evaluation. The clinical results were evaluated by Kim and Kim criteria. Satisfactory results were obtained in 65% of patients and this was closely associated with the rate of successful fusion. The results suggest that clinical outcome is closely related to the attainment of solid fusion and decompression or removal of the loose laminar fragment seems unnecessary in patients without major neurological symptoms.  相似文献   
89.
Hyperkalemia is generally associated with electrocardiographic (ECG) changes and these changes have been used to follow the effects of high serum potassium (K +) levels on the heart. It is known that chronic renal impairment may diminish the toxic effects of hyperkalemia on ECG abnormality formation. ,  and  Here, we report a case of recurrent severe hyperkalemia without any significant ECG changes in a patient with normal baseline renal function.  相似文献   
90.

Background

Hepatobiliary stone disease is one of the most common surgical conditions worldwide. There are multiple causative agents responsible for the formation of hepatobiliary stones, and bacterial infection is one of them. The presence of Helicobacter DNA species has been investigated in the biliary epithelium of patients with biliary diseases. However, conflicting results have been observed that may have been due to the small number of subjects studied, difficulty in obtaining a healthy control group, absence of controlling for confounding factors, or ethical and regional differences among populations.

Methods

We investigated the presence of Helicobacter pylori species by PCR of 26-kDa surface antigen specific to H. pylori in bile samples from 50 cases with hepatobiliary stones and 25 controls without hepatobiliary stones. The control group comprised of 20 patients of hydatid cyst disease of liver and 5 patients of right colonic growth.

Result

H. pylori was present in 20 bile samples among cases and was absent in 30 bile samples among cases. Among controls, H. pylori could not be detected. A significant association of the presence of H. pylori with hepatobiliary stone disease was seen (p < 0.001).

Conclusion

There is an association between bile infection with H. pylori and hepatobiliary stone disease.
  相似文献   
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