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41.
Pancreatic schwannoma is a very uncommon tumor of the pancreas,with only 27 cases reported.Most pancreatic schwannomas are benign,with only four malignant tumors reported.We describe a case of giant malignant schwannoma of the pancreatic body and tail,which involved the transverse colon.The tumor was treated successfully with en bloc distal splenopancreatectomy and colon resection.This is believed to be the first reported radical operation for malignant schwannoma of the pancreatic body,with infiltration of...  相似文献   
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Recent acknowledgment that multidrug resistant Stenotrophomonas maltophilia strains can cause severe infections has led to increasing global interest in addressing its pathogenicity. While being primarily associated with hospital-acquired respiratory tract infections, this bacterial species is also relevant to ophthalmology, particularly to contact lens-related diseases. In the current study, the capacity of Stenotrophomonas phage vB_SmaM_Ps15 to infect ocular S. maltophilia strains was investigated to explore its future potential as a phage therapeutic. The phage proved to be lytic to a range of clinical isolates collected in Australia from eye swabs, contact lenses and contact lens cases that had previously shown to be resistant to several antibiotics and multipurpose contact lenses disinfectant solutions. Morphological analysis by transmission electron microscopy placed the phage into the Myoviridae family. Its genome size was 161,350 bp with a G + C content of 54.2%, containing 276 putative protein-encoding genes and 24 tRNAs. A detailed comparative genomic analysis positioned vB_SmaM_Ps15 as a new species of the Menderavirus genus, which currently contains six very similar globally distributed members. It was confirmed as a virulent phage, free of known lysogenic and pathogenicity determinants, which supports its potential use for the treatment of S. maltophilia eye infections.  相似文献   
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Clinical Oral Investigations - To evaluate local effect of gaseous ozone on bacteria in deep carious lesions after incomplete caries removal, using chlorhexidine as control, and to investigate its...  相似文献   
46.
The aetiology of chronic obstructive pulmonary disease (COPD) is complex. While cigarette smoking is a well‐established cause of COPD, a myriad of assessed genetic factors has given conflicting data. Since gene‐environment interactions are thought to be implicated in aetiopathogenesis of COPD, we aimed to examine the matrix metalloproteinase (MMP) 9 C–1562T (rs3918242) functional variant and cigarette smoke in the pathogenesis of this disease. The distribution of the MMP9 C–1562T variant was analyzed in COPD patients and controls with normal pulmonary function from Serbia. Interaction between the C–1562T genetic variant and cigarette smoking was assessed using a case‐control model. The response of the C–1562T promoter variant to cigarette smoke condensate (CSC) exposure was examined using a dual luciferase reporter assay. The frequency of T allele carriers was higher in the COPD group than in smoker controls (38.4% vs. 20%; OR = 2.7, P = 0.027). Interaction between the T allele and cigarette smoking was identified in COPD occurrence (OR = 4.38, P = 0.005) and severity (P = 0.001). A functional analysis of the C–1562T variant demonstrated a dose‐dependent and allele‐specific response (P < 0.01) to CSC. Significantly higher MMP9 promoter activity following CSC exposure was found for the promoter harboring the T allele compared to the promoter harboring the C allele (P < 0.05). Our study is the first to reveal an interaction between the MMP9–1562T allele and cigarette smoke in COPD, emphasising gene‐environment interactions as a possible cause of lung damage in the pathogenesis of COPD. Environ. Mol. Mutagen. 57:447–454, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
47.

Objectives

The pulpal anesthetic and cardiovascular parameters obtained by 2 % lidocaine with epinephrine (LE; 1:80,000) or clonidine (LC; 15 mcg/ml) were studied in diabetes mellitus (DM) type 2 and healthy volunteers (72), after maxillary infiltration anesthesia.

Materials and methods

Onset and duration of pulpal anesthesia were measured by electric pulp tester; vasoconstrictive effect of used local anesthetic mixtures by laser Doppler flowmetry (LDF) through pulpal blood flow (PBF); systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were registered by electrocardiogram monitoring.

Results

Onset of pulpal anesthesia was shorter for LC than for LE in healthy, while it was not different in diabetic participants; duration of pulpal anesthesia was significantly longer in type 2 diabetic participants, regardless of used anesthetic mixture. Significant reduction of PBF with LE was observed during 45 min in healthy and 60 min in diabetic participants, while with LC such reduction was observed during 45 min in both groups. LE caused a significant increase of SBP in the 5th and 15th minutes in diabetic versus healthy participants, while LC decreased SBP from the 10th to 60th minutes in healthy versus diabetic participants.

Conclusions

DM type 2 influences duration of maxillary infiltration anesthesia obtained with LE and LC, and systolic blood pressure during LE anesthesia.

Clinical relevance

The obtained results provide elements for future protocols concerning intraoral local anesthesia in DM type 2 patients.
  相似文献   
48.
This paper contains a joint ESHG/ASHG position document with recommendations regarding responsible innovation in prenatal screening with non-invasive prenatal testing (NIPT). By virtue of its greater accuracy and safety with respect to prenatal screening for common autosomal aneuploidies, NIPT has the potential of helping the practice better achieve its aim of facilitating autonomous reproductive choices, provided that balanced pretest information and non-directive counseling are available as part of the screening offer. Depending on the health-care setting, different scenarios for NIPT-based screening for common autosomal aneuploidies are possible. The trade-offs involved in these scenarios should be assessed in light of the aim of screening, the balance of benefits and burdens for pregnant women and their partners and considerations of cost-effectiveness and justice. With improving screening technologies and decreasing costs of sequencing and analysis, it will become possible in the near future to significantly expand the scope of prenatal screening beyond common autosomal aneuploidies. Commercial providers have already begun expanding their tests to include sex-chromosomal abnormalities and microdeletions. However, multiple false positives may undermine the main achievement of NIPT in the context of prenatal screening: the significant reduction of the invasive testing rate. This document argues for a cautious expansion of the scope of prenatal screening to serious congenital and childhood disorders, only following sound validation studies and a comprehensive evaluation of all relevant aspects. A further core message of this document is that in countries where prenatal screening is offered as a public health programme, governments and public health authorities should adopt an active role to ensure the responsible innovation of prenatal screening on the basis of ethical principles. Crucial elements are the quality of the screening process as a whole (including non-laboratory aspects such as information and counseling), education of professionals, systematic evaluation of all aspects of prenatal screening, development of better evaluation tools in the light of the aim of the practice, accountability to all stakeholders including children born from screened pregnancies and persons living with the conditions targeted in prenatal screening and promotion of equity of access.  相似文献   
49.
A growing concern for the biopharmaceutical characterization of pharmaceutical products increased the interest in the evaluation and identification of physicochemical properties of drugs and dosage forms that govern its biological performance. In vitro and in vivo characteristics of two carbamazepine (CAS 298-46-4) immediate release tablets were investigated and compared in order to establish level A in vitro-in vivo correlation. An in vivo study was conducted as a controlled, two-way, complete cross-over, single dose, pharmacokinetic trial in 18 subjects. The in vitro study was performed using various dissolution media in order to evaluate their potential influence on drug release and distinguish the set of experimental conditions relevant to the in vivo behavior of the investigated drug products. Beside significant differences among in vitro release profiles, the in vivo data indicated bioequivalence of the two formulations. Although a high level of correlation between in vivo and in vitro data was observed in some media, there was no single in vitro-in vivo correlation model applicable to both investigated products. The obtained results add to the existing debate on the rationale for the use of surfactants in drug release media and their in vivo relevance, emphasizing the importance of in vitro dissolution testing in addition to in vivo bioequivalence testing.  相似文献   
50.
Using mixture experimental design, the effect of carbomer (Carbopol® 971P NF) and hydroxypropylmethylcellulose (Methocel® K100M or Methocel® K4M) combination on the release profile and on the mechanism of drug liberation from matrix tablet was investigated. The numerical optimization procedure was also applied to establish and obtain formulation with desired drug release. The amount of TP released, release rate and mechanism varied with carbomer ratio in total matrix and HPMC viscosity. Increasing carbomer fractions led to a decrease in drug release. Anomalous diffusion was found in all matrices containing carbomer, while Case — II transport was predominant for tablet based on HPMC only. The predicted and obtained profiles for optimized formulations showed similarity. Those results indicate that Simplex Lattice Mixture experimental design and numerical optimization procedure can be applied during development to obtain sustained release matrix formulation with desired release profile.  相似文献   
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