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71.
SYNOPSIS
Fluorimetric estimations of total 5HT in blood of 11 migrainous patients during an untreated migraine attack were made. Total blood 5HT dropped during a migraine attack to about 68% of its former level returning to preheadache values by the time the pain ceased. Mean values for total blood serotonin (ng/ml) were 65.1 at the beginning of a migraine attack, 57.9 at the peak, 61.0 at the end, and 91.2 in the headache free period (p<0.05). No correlation between the intensity of the headache and the concentration of 5HT during a migraine attack was found (p>0.5). The influence of some drugs upon fluorescence in blood of migraineurs was tested.  相似文献   
72.
73.
A wide range of local thermal ablative therapies have been developed in the treatment of non resectable hepatocellular carcinoma(HCC) in the last decade.Laser ablation(LA) and radiofrequency ablation(RFA) are the two most widely used of these.This article provides an up to date overview of the role of laser ablation in the local treatment of HCC.General principles,technique,image guidance and patient selection are discussed.A review of published data on treatment efficacy,long term outcome and complication rates of laser ablation is included and comparison with RFA made.The role of laser ablation in combination with transcatheter arterial chemoembolisation is also discussed.  相似文献   
74.
OBJECTIVE: To estimate gastric emptying rate in continuous ambulatory peritoneal dialysis (CAPD) patients, with or without indwelling dialysate, and to evaluate if there is an association between gastric motility and nutritional status. DESIGN: Single-center cross-sectional study. SETTING: Peritoneal Dialysis Unit, Medical Faculty, Jagiellonian University Hospital, Krakow, Poland. PATIENTS AND METHODS: 20 end-stage renal disease patients [11 F, 9 M; mean age 50.1 +/- 11 years; treated with CAPD for median 13.5 (2-61) months] were studied. All patients were nondiabetic and had no comorbidity that might influence gastric motility; nor were they receiving any prokinetic drugs. Gastric emptying rate was estimated with dynamic abdominal scintigraphy, started immediately after complete ingestion of a standard 200-kcal solid meal injected with 99mTc-labeled colloid, activity 40 MBq. Scintigraphy was performed at the rate of 23 images in 4-minute intervals for 92 minutes. Two consecutive procedures--with and without PD fluid--were performed at weekly intervals. As nutritional parameters, protein catabolic rate (PCR) and lean body mass (LBM) (based on urea and creatinine kinetics, respectively), body mass Index (BMI), and serum albumin were measured. RESULTS: All analyzed gastric emptying parameters, measured with or without dialysis fluid, were markedly prolonged in patients compared to values accepted as normal in the local scintigraphy unit. Gastric emptying half-time (T(1/2)) and percent of initial activity in minute 46 and in minute 92 were 60.5 +/- 25.0 minutes, 57.19% +/- 17.5%, and 33.8% +/- 20.9% with a full peritoneal cavity, and 63.9 +/- 28.2 minutes, 59.1% +/- 23.9%, and 33.9% +/- 24.3% with an empty peritoneal cavity. The T(1/2) and percent of initial activity after 46 and 92 minutes for healthy subjects were 39 +/- 9 minutes, 45% +/- 11%, and 15% +/- 6%, respectively. T(1/2) without dialysis fluid revealed a negative correlation with LBM and BMI values (r = -0.5, p < 0.05, and r = -0.56, p < 0.01; respectively). Patients with dialysate-free T(1/2) > 40 minutes were characterized by significantly lower serum albumin level compared to subjects with T(1/2) < 40 minutes (39.2 +/- 2.9 vs 42.9 +/- 3.6 g/L, p < 0.05). The values of all gastric emptying parameters measured for an empty abdomen were prolonged in subjects with BMI < 25 kg/m2. No difference was found between patients with and without PD fluid. CONCLUSIONS: Gastric emptying is markedly impaired in CAPD patients compared to healthy subjects. However, the presence of dialysate does not influence it significantly. Gastric emptying rate was negatively associated with the nutritional status of treated subjects. This association can be demonstrated when gastric motility is measured with an empty peritoneal cavity.  相似文献   
75.
OBJECTIVES: Markers of chronic inflammation, acute-phase reactants, and growth factors may be concomitantly involved in a number of pathologic processes in the general population and uremic patients. In addition, growth factors may influence peritoneal membrane transport characteristics. However, the association between plasma growth factors, markers of chronic inflammation, and peritoneal membrane transport remains largely unknown.The aim of this study was to evaluate the relationship between plasma levels of selected growth factors [basic fibroblast growth factor (bFGF), transforming growth factor beta1 (TGFbeta1), vascular endothelial growth factor (VEGF)] and markers of chronic inflammation [interleukin (IL)-6, C-reactive protein (CRP), and fibrinogen] in continuous ambulatory peritoneal dialysis (CAPD) patients.The potential link between the above substances and dialysis adequacy was also explored. DESIGN: Single-center, cross-sectional study. SETTING: Peritoneal Dialysis Unit, Medical Faculty, Jagiellonian University Hospital, Kraków, Poland. PATIENTS: 32 stable end-stage renal disease patients (13 M, 19 F; mean age 53.6 +/- 13.7 years) on CAPD for a median period of 19.5 months. Patients free from signs and symptoms of any inflammatory disease (including peritonitis) for at least 3 months were included into the study. All patients underwent measurements of dialysis dose [Kt/V, weekly creatinine clearance (wCCr)] and peritoneal solute transport using a standard peritoneal equilibration test (PET). METHODS: TGFbeta1, bFGF, VEGF, and IL-6 were measured with ELISA, CRP was assayed with immunonephelometry, and fibrinogen with Multifibren U reagent (Dade Behring Marburg GmbH, Marburg, Germany). Nephron 97 for Windows software was used to assess dialysis adequacy. RESULTS: Significant positive correlations between plasma bFGF and IL-6, as well as fibrinogen concentrations (R = 0.36, p < 0.05 and R = 0.39, p < 0.05, respectively), were found. VEGF correlated significantly with IL-6 and CRP (R = 0.65, p < 0.0001 and R = 0.51, p < 0.005, respectively). An association between VEGF and bFGF was also found (R = 0.59, p < 0.0005). Serum level of TGFbeta1 revealed no relationship with any marker of acute-phase activation, remaining growth factors, or dialysis adequacy. Positive correlation between TGFbeta1 concentration and dialysate-to-plasma ratio for creatinine in PET (R = 0.35, p < 0.05) was found. In addition, patients with lower solute transport (low/low-average transporters) had lower serum levels of both bFGF and TGFbeta1 compared to patients with higher solute transport. Patients with total wCCr > 60 L/ week/m2 were characterized by lower levels of bFGF and IL-6. Serum level of IL-6 and plasma levels of bFGF and VEGF were significantly lower among subjects with residual renal function (RRF) > 2.0 mL/minute. CONCLUSIONS: Our results indicate that systemic inflammation in peritoneal dialysis patients is associated with increased plasma VEGF and bFGF but not TGFbeta1. The negative correlation with RRF suggests that either the renal clearance of these cytokines and growth factors may contribute to their elimination, or cytokines and growth factors have a negative impact on RRF. We also suggest an association between serum levels of growth factors tested and peritoneal membrane function.  相似文献   
76.

Introduction

Chronic rhinosinusitis (CRS) is one of the most common diseases in Polish society. According to the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) 2012 the incidence of CRS among European and US citizens varies from 5 to 16%. Its treatment is based on pharmacotherapy or surgical procedure. The aim of the study was to evaluate the correlation between general health condition of the patients with CRS with each symptom of the disease before and after Functional Endonasal Sinus Surgery (FESS) procedure.

Materials and methods

The study was conducted on 100 patients, who evaluated symptoms and general health condition twice – before and after FESS, by means of visual analogue scale (VAS).

Results

Before FESS the highest severity among all symptoms concerned the nasal blockade and olfactory disorders, while after the procedure this ratio was found to be the opposite. All results were statistically significant (p < 0.05).

Conclusions

The authors emphasize a great role of general health assessment in patients with CRS as the element of proper diagnosis and better comprehension of patients’ needs. They indicate that the patient's estimation of the disease and its symptoms differs from the clinician's interpretation to much extent.  相似文献   
77.
78.
Archean microfossils: a reappraisal of early life on Earth   总被引:1,自引:0,他引:1  
The oldest fossils found thus far on Earth are c. 3.49- and 3.46-billion-year-old filamentous and coccoidal microbial remains in rocks of the Pilbara craton, Western Australia, and c. 3.4-billion-year-old rocks from the Barberton region, South Africa. Their biogenicity was recently questioned and they were reinterpreted as contaminants, mineral artefacts or inorganic carbon aggregates. Morphological, geochemical and isotopic data imply, however, that life was relatively widespread and advanced in the Archean, between 3.5 and 2.5 billion years ago, with metabolic pathways analogous to those of recent prokaryotic organisms, including cyanobacteria, and probably even eukaryotes at the terminal Archean.  相似文献   
79.
ObjectivesThe aim of the study was to assess the activity of cathepsin D in polyps removed during first-time FESS surgery and in recurrent polyps removed during successive FESS surgeries.Design and MethodsThe study examined 24 polyps: 11 polyps were removed during first-time surgical procedures (termed primary polyps in the study), and 13 recurrent polyps were removed in successive FESS surgeries (termed polyps after re-polypectomy in the study). The activity of cathepsin D was determined by measuring the tyrosine released from denatured hemoglobin.ResultThe average cathepsin D activity in polyps after re-polypectomy was 74% higher than the average activity in primary polyps, whereas the difference between the maximum and the minimum cathepsin D activities in polyps after re-polypectomy was twofold greater than the respective difference in primary polyps.ConclusionDifferences in cathepsin activity and the protein content, likely to be significant in the process of polyp recurrence, were observed in both groups of polyps.  相似文献   
80.
Existing epiretinal implants for the blind are designed to electrically stimulate large groups of surviving retinal neurons using a small number of electrodes with diameters of several hundred micrometers. To increase the spatial resolution of artificial sight, electrodes much smaller than those currently in use are desirable. In this study, we stimulated and recorded ganglion cells in isolated pieces of rat, guinea pig, and monkey retina. We used microfabricated hexagonal arrays of 61 platinum disk electrodes with diameters between 6 and 25 microm, spaced 60 microm apart. Charge-balanced current pulses evoked one or two spikes at latencies as short as 0.2 ms, and typically only one or a few recorded ganglion cells were stimulated. Application of several synaptic blockers did not abolish the evoked responses, implying direct activation of ganglion cells. Threshold charge densities were typically <0.1 mC/cm2 for a pulse duration of 100 micros, corresponding to charge thresholds of <100 pC. Stimulation remained effective after several hours and at high frequencies. To show that closely spaced electrodes can elicit independent ganglion cell responses, we used the multielectrode array to stimulate several nearby ganglion cells simultaneously. From these data, we conclude that electrical stimulation of mammalian retina with small-diameter electrode arrays is achievable and can provide high temporal and spatial precision at low charge densities. We review previous epiretinal stimulation studies and discuss our results in the context of 32 other publications, comparing threshold parameters and safety limits.  相似文献   
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