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1.
Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class.  相似文献   
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Established nonexpanding hematomas can be successfully treated with minimal morbidity using standard liposucstion techniques at the bedside or in an outpatient setting under local anesthesia. The authors presents a series of eight patients and discuss current concepts of dealing with this common and distressing surgical complication.  相似文献   
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Background  

Although the impact of Aboriginal status on HIV incidence, HIV disease progression, and access to treatment has been investigated previously, little is known about the relationship between Aboriginal ethnicity and outcomes associated with highly active antiretroviral therapy (HAART). We undertook the present analysis to determine if Aboriginal and non-Aboriginal persons respond differently to HAART by measuring HIV plasma viral load response, CD4 cell response and time to all-cause mortality.  相似文献   
5.
Primary congenital glaucoma (gene symbol: GLC3) is an ocular disorder that occurs for 0.01-0.04% of blind people. In the majority of familial cases reported so far, this condition is inherited as an autosomal recessive trait. We have recently used a group of 17 GLC3 families with a minimum of two affected offspring and consanguinity in most of the parental generation and mapped the first GLC3 locus (GLC3A) to the 2p21 region. Six families did not show any linkage to the GLC3A locus and thus provided evidence for genetic heterogeneity of this disorder. A total of eight families unlinked to the 2p21 region were used to search for the chromosomal location of the second GLC3 locus. Herein, we describe mapping of a new locus (designated GLC3B) for primary congenital glaucoma to the short arm of chromosome 1 (1p36.2-36.1) that is situated centromeric to the neuroblastoma and Charcot-Marie-Tooth type 2A (CMT2A) loci. A total of 17 DNA markers were genotyped from this region of chromosome 1. Four families showed no recombination with the two markers D1S2834 and D1S402 with a maximum lod score of 4.510 and 4.157 respectively. Pairwise and multipoint linkage analysis and inspection of the haplotypes revealed that the remaining four families are not linked to this part of chromosome 1, thus providing further evidence that at least one more locus for the autosomal recessive form of GLC3 must exist in the genome. Based on the recombination events, the overall linkage map of this region is: tel-D1S1192-D1S1635-D1S1193 - (D1S1597/-D1S489/D1S228)- [GLC3B/D1S2834/D1S402] - (D1S1176/D1S507/D1S407) - D1S2728-(MFAP2/D1S170) - D1S1368 - D1S436- D1S1592-cen.   相似文献   
6.
Purpose. To visualize the transport pathway(s) of high molecular weight model compounds across rat nasal epithelium in vivousing confocal laser scanning microscopy. Furthermore, the influence of nasal absorption enhancers (randomly methylated -cyclodextrin and sodium taurodihydrofusidate) on this transport was studied. Methods. Fluorescein isothiocyanate (FITC)-labelled dextrans with a molecular weight of 3,000 or 10,000 Da were administered intranasally to rats. Fifteen minutes after administration the tissue was fixed with Bouin. The nasal septum was surgically removed and stained with Evans Blue protein stain or DiIC18(5) lipid stain prior to visualization with the confocal laser scanning microscope. Results. Transport of FITC-dextran 3,000 across nasal epithelium occurred via the paracellular pathway. Endocytosis of FITC-dextran 3,000 was also shown. In the presence of randomly methylated -cyclodextrin 2% (w/v) similar transport pathways for FITC-dextran 3,000 were observed. With sodium taurodihydrofusidate 1% (w/v) the transport route was also paracellular with endocytosis, but cells were swollen and mucus was extruded into the nasal cavity. For FITC-dextran 10,000 hardly any transport was observed without enhancer, or after co-administration with randomly methylated -cyclodextrin 2% (w/v). Co-administration with sodium taurodihydrofusidate 1% (w/v) resulted in paracellular transport of FITC-dextran 10,000, but morphological changes, i.e. swelling of cells and mucus extrusion, were observed. Conclusions. Confocal laser scanning microscopy is a suitable approach to visualize the transport pathways of high molecular weight hydrophilic compounds across nasal epithelium, and to study the effects of absorption enhancers on drug transport and cell morphology.  相似文献   
7.
The absorption enhancing effect of -, -, and -cyclodextrin (CD), dimethyl--cyclodextrin (DMCD), and hydroxypropyl--cyclodextrin (HPCD) on intranasally administered insulin was investigated in rats. Coadministration of 5% (w/v) DMCD to the insulin solution resulted in a high bioavailability, 108.9 ± 36.4% (mean ± SD, n = 6), compared to i.v. administration, and a strong decrease in blood glucose levels, to 25% of their initial values. Coadministration of 5% -CD gave rise to an insulin bioavailability of 27.7 ± 11.5% (mean ± SD, n = 6) and a decrease in blood glucose to 50% of its initial value. The rate of insulin absorption and the concomitant hypoglycemic response were delayed for the -CD-containing solution as compared to the DMCD preparation. The other CDs, HPCD (5%), -CD (1.8%), and -CD (5%), did not have significant effects on nasal insulin absorption. DMCD at a concentration of 5% (w/v) induces ciliostasis as measured on chicken embryo tracheal tissue in vitro, but this effect is reversible. In conclusion, DMCD is a potent enhancer of nasal insulin absorption in rats.  相似文献   
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PLGA-PEI nanoparticles for gene delivery to pulmonary epithelium.   总被引:5,自引:0,他引:5  
Pulmonary gene delivery is thought to play an important role in treating genetically related diseases and may induce immunity towards pathogens entering the body via the airways. In this study we prepared poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles bearing polyethyleneimine (PEI) on their surface and characterized them for their potential in serving as non-viral gene carriers to the pulmonary epithelium. Particles that were synthesized at different PLGA-PEI ratios and loaded with DNA in several PEI-DNA ratios, exhibited narrow size distribution in all formulations, with mean particle sizes ranging between 207 and 231 nm. Zeta potential was strongly positive (above 30 mV) for all the PEI-DNA ratios examined and the loading efficiency exceeded 99% for all formulations. Internalization of the DNA-loaded PLGA-PEI nanoparticles was studied in the human airway submucosal epithelial cell line, Calu-3, and DNA was detected in the endo-lysosomal compartment 6 h after particles were applied. Cytotoxicity of these nanoparticles was dependent on the PEI-DNA ratio and best cell viability was achieved by PEI-DNA ratios 1:1 and 0.5:1. These findings demonstrate that PLGA-PEI nanoparticles are a potential new delivery system to carry genes to the lung epithelium.  相似文献   
10.
The uptake of estradiol and progesterone into the cerebrospinal fluid (CSF) after intranasal and intravenous administration in rats was investigated. Each animal received estradiol intranasally (40 microg/rat) and by intravenous infusion (10 microg/rat) into the jugular vein using a vascular access port. Hereafter, the same set of rats was treated with progesterone intranasally (200 microg/rat) and by intravenous infusion (104 microg/rat). Following nasal delivery, both steroid hormones reach Cmax values in plasma and CSF at 15 min after administration. Intravenous infusion of estradiol and progesterone shows comparable plasma and CSF concentration-time profiles compared to the nasal route. For both hormones the AUCCSF/AUCplasma ratios (mean +/- SD) after intranasal delivery (estradiol 2.3 +/- 1.1%; progesterone 1.9 +/- 0.7%) do not differ significantly from the ratios shown after intravenous infusion (estradiol 2.0 +/- 0.6%; progesterone 2.2 +/- 0.8%). These results indicate that after nasal delivery estradiol and progesterone are rapidly absorbed into the systemic circulation, from where the non-protein bound hormones probably enter the CSF by crossing the blood-brain barrier. No extra direct nose-CSF transport could be demonstrated.  相似文献   
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