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91.
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Objectives

(1) Determine the relationships among a family's specific answers to health history questions and their child's risk for aspiration as determined by a swallow study. (2) Identify key factors which may predict a child's risk for aspiration.

Methods

Answers to questions and results of Functional Endoscopic Evaluation of Swallow (FEES) and/or Video Swallow Study (VSS) for a sample of 198 children were collected. Subjects were categorized into groups: “aspiration”, “penetration” or “no aspiration or penetration”. Logistic regression modeling was used to determine the contribution of certain characteristics to the odds of aspiration. A model for predicting aspiration or penetration based on those characteristics was assessed. The sensitivity and specificity of the model in predicting aspiration and penetration was determined.

Results

One hundred ninety eight subjects had a FEES or VSS. Of these, 18% (n = 36) aspirated and 21% (n = 42) were found to have penetration. Many of the factors identified in the health history were found to be significantly associated with aspiration or penetration. The variables “demonstrated aspiration” (this included parent or caregiver seeing food in the tracheotomy tube or aspiration noted on a previous FEES or VSS) (p = 0.02), “hypotonia” (p = 0.02) and “tracheotomy” (p = 0.001) were most predictive of aspiration. History of tracheotomy was found to have an inverse relationship with aspiration. “gastroesophageal reflux” (GER) (p = 0.0007) was most significantly associated with penetration, followed by “prematurity” (p = 0.03) and “developmental delays” (p = 0.04). Based on the prediction model, the probabilities for a child with a history of combinations of the above variables to have aspiration or penetration were calculated.

Conclusions

Significant relationships exist between aspiration or penetration and the family's answers about their child's medical history. Practitioners should consider a swallow assessment whenever a child has a history which includes variables with a strong association with aspiration or penetration.  相似文献   
94.
AIM: To describe the incidence and risk factors of vision reducing cataract in skin smear positive lepromatous patients. METHODS: Prospective longitudinal cohort study: 212 newly diagnosed lepromatous patients were followed during the two years of treatment with multidrug therapy and for a further five years, with biannual ocular examinations. Incidence of vision reducing (< or =6/18) cataract was calculated as the number of patients with cataract per person year of cataract-free follow up among those who did not have cataract at baseline. RESULTS: Cataract was present in 27 (11%) of lepromatous patients at diagnosis. Forty nine patients (2.87%/person year (95% confidence interval (CI), 2.17% to 3.80%)) developed cataract during a total follow up period of 1704 person years; 45 of these were > or =41 years old and were followed for a total of 638 person years with an incident rate of 0.070 (95% CI, 0.0523 to 0.094). Stepwise multiple regression confirmed the association of age (per decade) (hazard ratio (HR) = 2.50 (95% CI, 1.82 to 2.78), p<0.001), clofazimine crystals on the cornea (HR = 49.92 (5.48 to 454.82), p = 0.001), grade 2 deformity in all limbs (HR = 3.17 (1.12 to 8.97), p = 0.029), and uveal inflammation (HR = 3.52 (1.42 to 8.67), p = 0.006). No significant association was found with oral steroids. CONCLUSIONS: Cataract develops at the rate of 7%/person year in lepromatous patients over 40 years of age. It is associated with increasing age, subclinical intraocular inflammation, and grade 2 deformity.  相似文献   
95.
RATIONALE: To examine the management and outcomes of choanal atresia in children with CHARGE association compared with non-CHARGE children. METHODS: This is a retrospective chart review at a tertiary care children's hospital examining the management and outcomes of choanal atresia repair in children with CHARGE from 1990-2005. At least two CHARGE features were used to define these children. Children with CHARGE association were compared with non-CHARGE children regarding type of atresia, method of repair, post-operative management, re-stenosis rate and revision surgery. RESULTS: Fifty-seven children (36 female, 21 male) with complete records were identified with 24% diagnosed with CHARGE association. The median age of primary repair was 0.75 months for CHARGE and 15 months for non-CHARGE children (p=0.047). Unilateral atresia was diagnosed in 36% of CHARGE children and 81% of non-CHARGE children. Bilateral atresia was diagnosed in 64% of CHARGE and 19% of non-CHARGE children (p=0.006). The median duration of stent placement was slightly longer in the CHARGE group with no difference in the median number of post-operative dilations. Of those with CHARGE, 36% required revision surgery compared to 44% of the non-CHARGE subjects (p=0.58). Of those undergoing primary transnasal repairs, 40% of the CHARGE and 37% of the non-CHARGE patients failed. 50% of CHARGE patients with primary transnasal repair for bilateral atresia failed. Only 25% of transpalatal CHARGE repairs failed, while 75% of transpalatal repairs failed in the non-CHARGE group. The median follow-up was 24.6 months for CHARGE and 24.9 months for non-CHARGE patients. CONCLUSIONS: Children with CHARGE and unilateral choanal atresia can be managed successfully with a transnasal approach. However, our data, as well as prior published reports, suggests that CHARGE patients with bilateral atresia should have primary transpalatal repairs due to the high failure rate with the transnasal approach in this population.  相似文献   
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97.
PURPOSE: Schnyder crystalline corneal dystrophy (SCCD; MIM 121800) is a rare autosomal dominant disease characterized by an abnormal increase in cholesterol and phospholipid deposition in the cornea, leading to progressive corneal opacification. Although SCCD has been mapped to a genetic interval between markers D1S1160 and D1S1635, reclassification of a previously unaffected individual expanded the interval to D1S2667 and included nine additional genes. Three candidate genes that may be involved in lipid metabolism and/or are expressed in the cornea were analyzed. METHODS: DNA samples were obtained from six families with clinically confirmed SCCD. Analysis of FRAP1, ANGPTL7, and UBIAD1 was performed by PCR-based DNA sequencing, to examine protein-coding regions, RNA splice junctions, and 5' untranslated region (UTR) exons. RESULTS: No disease-causing mutations were found in the FRAP1 or ANGPTL7 gene. A mutation in UBIAD1 was identified in all six families: Five families had the same N102S mutation, and one family had a G177R mutation. Predictions of the protein structure indicated that a prenyl-transferase domain and several transmembrane helices are affected by these mutations. Each mutation cosegregated with the disease in four families with DNA samples from both affected and unaffected individuals. Mutations were not observed in 100 control DNA samples (200 chromosomes). CONCLUSIONS: Nonsynonymous mutations in the UBIAD1 gene were detected in six SCCD families, and a potential mutation hot spot was observed at amino acid N102. The mutations are expected to interfere with the function of the UBIAD1 protein, since they are located in highly conserved and structurally important domains.  相似文献   
98.
PURPOSE: Mutations in keratocan (KERA), a small leucine-rich proteoglycan, have recently been shown to be responsible for cases of autosomal recessive cornea plana (CNA2). A consanguineous pedigree in which cornea plana cosegregated with microphthalmia was investigated by linkage analysis and direct sequencing. METHODS: Linkage was sought to polymorphic microsatellite markers distributed around the CNA2 and microphthalmia loci (arCMIC, adCMIC, NNO1, and CHX10) using PCR and nondenaturing polyacrylamide gel electrophoresis before KERA was directly sequenced for mutations. RESULTS: Positive lod scores were obtained with markers encompassing the CNA2 locus, the maximum two-point lod scores of 2.18 at recombination fraction theta = 0 was obtained with markers D12S95 and D12S327. Mutation screening of KERA revealed a novel single-nucleotide substitution at codon 215, which results in the substitution of lysine for threonine at the start of a highly conserved leucine-rich repeat motif. Structural modeling predicts that the motifs are stacked into an arched beta-sheet array and that the effect of the mutation is to alter the length and position of one of these motifs. CONCLUSIONS: This report describes a novel mutation in KERA that alters a highly conserved motif and is predicted to affect the tertiary structure of the molecule. Normal corneal function is dependent on the regular spacing of collagen fibrils, and the predicted alteration of the tertiary structure of KERA is the probable mechanism of the cornea plana phenotype.  相似文献   
99.
Objective: To investigate the biogenic synthesis of silver nanoparticles (AgNPs) using partially purified ethylacetate extract of Nannochloropsis sp. hexane (EAENH) fraction of microalga. Methods: The green synthesis ofAgNPs was confirmed with UV-Vis spectrum which shows the surface plasmon resonance (SPR) at 421 nm. FourierTransform Infrared Spectra (FTIR) presented the involvement of functional groups like carboxyl groups of fatty acids,tetraterpenoids of xanthophylls, hydroxyl groups of polyphenols, carbonyl and amide linkage of proteins in the AgNPsynthesis. Gas Chromatography-Mass Spectrometry analysis (GCMS) revealed that phytochemicals like octadecanoicacid and hexadecanoic acid imply in capping, bioreduction, and stabilization of AgNps. Result: High-resolutionTransmission electron microscope (HRTEM), Dynamic light scattering (DLS), X-ray diffraction (XRD) and EDXanalysis showed the crystalline form of the AgNPs with Z-average size 57.25 nm. The zeta potential value of -25.7mV demonstrated the negative surface charge and colloidal stability of AgNPs. The antimicrobial activity of AgNPsdisplayed effective inhibition zone against selected bacterial and fungal pathogens. In vitro, antioxidant effects wereassessed by 1,1-diphenyl-2-picryl-hydrazyl (DPPH), hydrogen peroxide and reducing power assays which revealedexcellent scavenging potential for AgNPs than the extracts. The anti-proliferative potential of biofabricated AgNPsand extracts on Human Non-small lung cancer cell line (A549) was assessed using 3–(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay with IC50 values of 15 μgmL-1 and 175 μgmL-1 respectively. Conclusion:The study reveals that the microalgae-mediated AgNPs possesses potent antimicrobial and antioxidant activity alongwith the ability to stimulate apoptosis in A-549 cell line.  相似文献   
100.
Ecotoxicology - The availability of pharmaceutically active compounds (PhACs) in surface waters and suspended solids/sediments presents an ecological hazard of chronic exposure to non-target...  相似文献   
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