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101.
102.
Mycoplasma genitalium is known to cause nonchlamydial, nongonococcal urethritis in men and to be associated with pelvic inflammatory disease in women. Specific and sensitive PCR methods are needed for diagnosis of this bacterium because it is very difficult to culture from patient samples. To determine the bacterial load in patients' specimens, a quantitative real-time LightCycler PCR was developed. The housekeeping gene gap encoding glyceraldehyde-3-phosphate dehydrogenase was chosen as the target gene. The assay could consistently detect five genome copies per reaction. To evaluate the PCR, we tested 246 selected urethral swab samples from men attending a clinic for sexually transmitted diseases. Eighty-two of the samples were found positive for M. genitalium by a conventional 16S rRNA gene PCR assay, whereas 164 samples were randomly chosen among those tested negative. Of the positive samples, 78 (95.1%) were found positive, whereas 6 (3.7%) of the negatives were found positive by the LightCycler assay. The patient samples were also tested with a quantitative TaqMan assay, and the bacterial load was compared to the LightCycler results. A good linear correlation between the LightCycler and the TaqMan assays was found with a correlation coefficient of 0.89 and a slope of 0.99. Significantly more M. genitalium-positive men had urethritis, discharge, and dysuria than had M. genitalium-negative men. The M. genitalium DNA load in samples from patients with urethritis was significantly higher than in samples from those without (61 and 2.9 copies/microl, respectively [P = 0.0005]). This assay may prove useful in the monitoring of treatment and for optimizing sample preparation methods.  相似文献   
103.
Ischaemic retinal cell degeneration seems to involve both NMDA and non-NMDA receptor over stimulation. However, different retinal cell types differ largely in their susceptibility to excitatory amino acid induced neurotoxicity. We have investigated the vulnerability of GABAergic cells in the rabbit retina to the non-NMDA receptor agonist kainic acid (KA). The distribution of GABA immunoreactivity (GABA-IR) was examined in the central inferior retina at different survival times (5 h–6 days) following an intra-ocular injection of 140 nmol KA and compared to that of control and untreated retinas. In the normal retina, the majority of GABA-positive cells (79%) were located in the inner nuclear layer (INL), in one to four cell rows next to the inner plexiform layer (IPL), and in one cell row next to the outer plexiform layer (OPL). The remainder (21%) were found in the ganglion cell layer (GCL). Dense immunoreactivity was seen throughout the IPL. In the OPL, stained dots and occasional immunoreactive large processes could be seen. KA-exposed retinas processed for GABA immunocytochemistry 5 and 24 h after the injection showed an 85% reduction in the number of GABA immunoreactive cells. About the same degree of depletion was seen among GABA-IR cells located at different retinal levels. However, at these survival times, immunostaining was observed in three distinct bands in the IPL, indicating that the vulnerability to KA is not uniformly distributed among all GABAergic cells. At 48 h, an additional decrease in the number of labelled cells was noted, but immunoreactive cells were still found both in the INL and GCL. Even 6 days after KA treatment, a few stained cell bodies were seen in the INL next to the IPL, as well as a few processes in the IPL. The study shows that KA receptor overstimulation induces a marked depletion of the endogenous cellular GABA pools of the central rabbit retina, most likely as a result of GABAergic cell loss. However, a small population of GABAergic cells located in the INL appears to be less vulnerable to the toxic effects of 140 nmol KA.  相似文献   
104.
The humoral immune response to Chlamydia outer membrane protein 2 (Omp2) was studied. Omp2 is a highly genus-conserved structural protein of all Chlamydia species, containing a variable N-terminal fragment. To analyze where the immunogenic parts were localized, seven highly purified truncated fusion proteins constituting different regions of the protein were produced (Chlamydia pneumoniae-Omp2aa23-aa93, Chlamydia psittaci-Omp2aa23-aa94, and Chlamydia trachomatis-Omp2aa23-aa84, aa87-aa547, aa23-aa182, aa167-aa434, aa420-aa547). By an enzyme-linked immunosorbent assay with serologically defined patient sera, Omp2 was found to be a major immunogen of both C. pneumoniae and C. trachomatis infections (P 0.0001). The humoral immune responses were not confined to any particular region of the Omp2 protein, and no species-specific anti-Omp2 immunoglobulins were detected.  相似文献   
105.
106.
Dietary omega‐3 fatty acids accumulate and are actively retained in central nervous system membranes, mainly in synapses, dendrites and photoreceptors. Despite this selective enrichment, their impact on synaptic function and plasticity has not been fully determined at the molecular level. In this study, we explored the impact of omega‐3 fatty acid deficiency on synaptic function in the hippocampus. Dietary omega‐3 fatty acid deficiency for 5 months after weaning led to a 65% reduction in the concentration of docosahexaenoic acid in whole brain synaptosomal phospholipids with no impact on global dopaminergic or serotonergic turnover. We observed reduced concentrations of glutamate receptor subunits, including GluA1, GluA2 and NR2B, and synaptic vesicle proteins synaptophysin and synaptotagmin 1 in hippocampal synaptosomes of omega‐3 fatty acid‐deficient mice as compared to the omega‐3 fatty acid rich group. In contrast, an increased concentration of neuronal inositol 1,4,5‐trisphosphate‐receptor (IP3‐R) was observed in the deficient group. Furthermore, omega‐3 fatty acid deficiency reduced the long‐term potentiation (LTP) in stratum oriens of the hippocampal CA1 area, but not in stratum radiatum. Thus, omega‐3 fatty acids seem to have specific effects in distinct subsets of glutamatergic synapses, suggesting specific molecular interactions in addition to altering plasma membrane properties on a more global scale.  相似文献   
107.
There is an increased but variable risk of epilepsy in autism spectrum disorders. The objective of this study is to compare the prevalence and types of epilepsy and other central nervous system (CNS) diseases in a clinical sample of 89 individuals diagnosed as children with atypical autism (AA) with 258 matched controls from the general population. Diagnoses were based on data from the nationwide Danish National Hospital Register. The average observation time was 32.9 years, and mean age at follow-up was 48.5 years. Of the 89 individuals with AA, 20 (22.5%) were registered with at least one epilepsy diagnosis against 11 (4.3%) in the comparison group (P < 0.0001; OR 6.5; 95% CI 3.0–14.2). Other CNS diseases occurred with low frequency in both groups, and no single CNS disease (except epilepsy) was significantly more frequent among patients with AA. Low intelligence was a risk factor for epilepsy in AA.  相似文献   
108.
Study Type – Symptom prevalence (prospective cohort)
Level of Evidence 1b

OBJECTIVE

To characterize and evaluate a Danish patient population with bladder pain syndrome/interstitial cystitis (BPS/IC), using a working definition for BPS/IC incorporating six variables, and a set of criteria defined by the European Society for the Study of Interstitial Cystitis (ESSIC); to describe the clinical course and treatment intensity in relation to these variables.

PATIENTS AND METHODS

Clinical data were obtained retrospectively from medical records for 349 consecutive patients with IC referred to the Department of Urology, Copenhagen University Hospital Herlev, Denmark between 1966 and 2008. The median (range) age at diagnosis was 53 (16–88) years; 64% were followed for at least 2 years. The outcome was expressed in terms of treatment intensity and was correlated with clinical data (pain, nocturnal frequency, bladder capacity, mucosal glomerulations, detrusor mastocytosis, detrusor intrafascicular fibrosis, IFF).

RESULTS

All patients had pain and 75% had nocturia at least twice. The bladder capacity estimated under general anaesthesia was <500 mL in 42%; 53% presented with detrusor mastocytosis (≥28 mast cells/mm2) and 50% with IFF. The detrusor mast cell count (P < 0.001), IFF (P = 0.004) and nocturnal frequency (P = 0.043) had statistically significant prognostic value for treatment intensity, whereas bladder capacity and glomerulations were not significant.

CONCLUSION

Nocturia, detrusor mastocytosis and IFF are associated with multiple treatments and presumed failure of standard urological therapy in patients with BPS/IC, while bladder capacity and glomerulations are not. Valid conclusions cannot be drawn because of numerous limitations to the study.  相似文献   
109.
110.
Boron Neutron Capture Therapy (BNCT) effectiveness depends on the preferential sequestration of boron in cancer cells relative to normal tissue cells. We present a novel strategy for sequestering boron using an adenovirus expressing the sodium iodide symporter (NIS). Human glioma grown subcutaneously in athymic mice and orthotopic rat brain tumors were transfected with NIS using a direct tumor injection of adenovirus. Boron bound as sodium tetrafluoroborate (NaBF(4)) was administered systemically several days after transfection. Tumors were excised hours later and assessed for boron concentration using inductively coupled plasma atomic emission spectroscopy. In the human glioma transfected with NIS, boron concentration was more than 10 fold higher with 100 mg/kg of NaBF(4), compared to tumor not transfected. In the orthotopic tumor model, the presence of NIS conferred almost 4 times the boron concentration in rat tumors transfected with human virus compared with contralateral normal brain not transfected. We conclude that adenovirus expressing NIS has the potential to be used as a novel boron delivery agent and should be explored for future clinical applications.  相似文献   
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