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991.
BackgroundPandemic 2009 H1N1 influenza A (pH1N1) virus has caused substantial morbidity and mortality globally and continues to circulate. Although pH1N1 viral antigens have been demonstrated in various human tissues by immunohistochemistry (IHC), cellular localization of pH1N1 RNA in these tissues has largely remained uninvestigated.ObjectivesTo examine the distribution of pH1N1 RNA in tissues of fatal cases in order to understand the virus tissue tropism, replication and disease pathogenesis.Study designFormalin-fixed, paraffin embedded autopsy tissues from 21 patients with confirmed pH1N1 infection were analyzed by influenza A IHC and by in situ hybridization (ISH) using DIG-labeled sense (detects viral RNA) and antisense probes (detects positive-stranded mRNA and cRNA) targeting the nucleoprotein gene of pH1N1 virus.ResultspH1N1 RNA was localized by ISH in 57% of cases while viral antigens were detected by IHC in 76%. However, in cases with a short duration of illness (1–3 days), more cases (69%) were positive by ISH than IHC (62%). Strong ISH staining was detected by antisense probes in the alveolar pneumocytes of the lungs, mucous glands and in lymph nodes. IHC staining of viral antigens was demonstrated in the lung pneumocytes and mucous glands, but no immunostaining was detected in any of the lymph nodes examined.ConclusionsThis study demonstrates cellular localization of positive-stranded pH1N1 RNA in the lungs, mucous glands and lymph nodes that suggests viral replication in these tissues. The novel ISH assay can be a useful adjunct for the detection of pH1N1 virus in tissues and for pathogenesis studies.  相似文献   
992.
Twenty-eight examples of postburn contracture of the neck managed during the last 5 years gave us a better understanding of the problems of anaesthesia, contracture release, skin grafting, splintage and maintenance of the fully release state. The severe contracture should be incised before intubation under a local anaesthetic agent. The release should include the adjoining contractures of mandibular and pectoral regions lest the skin graft is pulled by the existing contracture. Haemostasis should be meticulously secured to avoid graft loss. Splintage should be a static splint for 4-6 weeks followed by a dynamic splint until the applied graft becomes soft, supple and wrinkle free. Ideally, however, contractures should be prevented by nursing the patient with a neck extension in the acute phase and wearing a cervical collar during the subacute phase of wound healing.  相似文献   
993.
The Veterans Affairs Hypertension Primary Care Longitudinal Cohort (VAHC) was initiated in 2003 as a pilot study designed to link the VA electronic medical record system with individual genetic data. Between June 2003 and December 2004, 1,527 hypertensive participants were recruited. Protected health information (PHI) was extracted from the regional VA data warehouse. Differences between the clinic and mail recruits suggested that clinic recruitment resulted in an over-sampling of African Americans. A review of medical records in a random sample of study participants confirmed that the data warehouse accurately captured most selected diagnoses. Genomic DNA was acquired non-invasively from buccal cells in mouthwash; ~ 96.5 per cent of samples contained DNA suitable for genotyping, with an average DNA yield of 5.02 ± 0.12 micrograms, enough for several thousand genotypes. The coupling of detailed medical databases with genetic information has the potential to facilitate the genetic study of hypertension and other complex diseases.  相似文献   
994.
Bilateral ganglionic masses, likely representing fused superior and middle cervical sympathetic ganglia, were found in the mid-neck region of a cadaver during routine dissection. The displacement of the superior cervical ganglion from its normal location is a striking anomaly that does not appear to have been reported earlier. This observation may be clinically relevant for avoiding misdiagnosis of such masses as Schwannomas or other tumors. In addition, in cases where the superior cervical ganglion is absent from its usual location, it should be sought in the mid-neck region.  相似文献   
995.
Purpose:To compare the optical coherence tomography (OCT)-based retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness at the posterior pole, and total macular thickness of women with the polycystic ovarian syndrome (PCOS) versus healthy reproductive age group females.Methods:The study included 110 eyes of 55 diagnosed cases of PCOS (study group) and 110 eyes of 55 healthy reproductive age group (15–49 years) females (control group). All patients underwent a detailed ophthalmological evaluation followed by an OCT to measure their retinal thicknesses. The body mass index (BMI) of patients was noted and compared with the retinal thickness. Also, the lipid profile and serum testosterone levels of PCOS patients were recorded.Results:The retinal thicknesses in the two study were similar and there was no statistically significant difference. However, on stratification with BMI, it was seen that in patients with BMI>30 kg/m2, the superior Retinal Nerve Fibre Layer (RNFL) was significantly thicker in the PCOS group as compared with the control group (P = 0.0006). The mean serum testosterone level in patients with PCOS was 141.3 ± 23.2. Also, 65.45% of patients had a serum testosterone level of more than 70 ng/dL. The mean HDL cholesterol in patients with PCOS was 38.1 ± 15.6. The mean LDL cholesterol in PCOS patients was 98.4 ± 21.7, and the mean total cholesterol in PCOS patients was 153.6 ± 27.3.Conclusion:Androgens have a trophic action on nerves, which could explain the increased RNFL thickness in these patients.  相似文献   
996.
Angiotensin converting enzyme (ACE) inhibitors, enalapril (5 to 20 mg twice daily) or captopril (25 to 100 mg thrice daily) and matching ACE inhibitor placebos were given to 32 moderate-to-severe essential hypertension patients who were already on 50 mg hydrochlorothiazide daily. Alpha-methyldopa (250 to 500 mg twice daily) was given to 16 patients following 6 weeks of ACE inhibitor therapy. Both enalapril and captopril significantly (p less than 0.05) lowered the supine and upright blood pressures (BPs) (acutely and long-term) without significant reflex heart rate changes. The BPs of enalapril patients were, however, significantly lower (supine diastolic p less than 0.03, supine systolic p less than 0.05, and upright diastolic p less than 0.04) than those of captopril patients when compared by repeated measures of analysis of variance. Eleven enalapril patients have been followed for 1 year with continued BP control. Skin rash occurred in one captopril patient and reversible renal insufficiency developed in two enalapril patients during the first 16 weeks. It is concluded that (although both ACE inhibitors lowered BP, enalapril was more effective than captopril and twice-daily enalapril was well tolerated during 52 weeks of treatment.  相似文献   
997.
998.
Our objective was to characterize, by DSC and XRD, the equilibrium thermal behavior of frozen aqueous solutions containing polyethylene glycol (PEG) and sucrose. Aqueous solutions of (i) PEG (2.5–50% w/w), (ii) sucrose (10% w/v) with different concentrations of PEG (1–20% w/v), and (iii) PEG (2% or 10% w/v) with different concentrations of sucrose (2–20% w/v), were cooled to ? 70°C at 5°C/min and heated to 25°C at 2°C/min in a DSC. Annealing was performed for 2 or 6 h at temperatures, ranging from ? 50 to ? 20°C. Experiments under similar conditions, on select compositions, were also performed in a powder X-ray diffractometer. Two endotherms, observed during heating of a frozen PEG solution (10% w/v), were attributed to PEG–ice eutectic melting and ice melting, and were confirmed by XRD. At higher PEG concentrations (> 37.5% w/w), only the endotherm attributed to the PEG–ice eutectic melting was observed. Inclusion of sucrose decreased both PEG–ice melting and ice melting temperatures. In unannealed systems with a fixed sucrose concentration (10% w/v), the PEG–ice melting event was not observed at PEG concentration < 5% w/v. Annealing for 2–6 h facilitated PEG crystallization. In unannealed systems with a fixed PEG concentration (10% w/v), an increase in the sucrose concentration increased the devitrification but decreased the PEG–ice melting temperature. The PEG–ice melting temperatures obtained by DSC and XRD were in good agreement. In ternary systems at a fixed PEG to sucrose ratio, the Tg as well as the PEG–ice melting temperature were unaffected by the total solute concentration. XRD confirmed the absence of a PEG–sucrose–ice ternary eutectic. When the PEG to sucrose ratio was systematically varied, the PEG–ice and ice melting temperatures decreased with an increase in the sucrose concentration. However, at a fixed PEG to sucrose ratio, the PEG–ice melting temperature, was unaffected by the total solute concentration.  相似文献   
999.
The study was undertaken to evaluate the impact of deltamethrin impregnated mosquito nets on malaria incidence, mosquito density, any adverse side effect among users and collateral effects on bed bugs and houseflies. A field trial was carried out over a period of three years in two adjacent military stations at Allahabad (UP), keeping one as a trial and other as a control station. During first year, baseline data were collected and during next two years residual spray was replaced with use of deltamethrin impregnated mosquito nets in trial station. The use of deltamethrin-treated bed nets resulted in a significant decline in malaria incidence and annual parasite index (API). The average mosquito density of anopheline mosquitoes decreased by 67.8% and culicine by 49.7%. The insecticide was found safe for use amongst troops and had favourable collateral effects against bed bugs and flies. Use of deltamethrin impregnated bed nets has beneficial impact on integrated control of malaria.  相似文献   
1000.
The aim of this study was to evaluate the usefulness of measuring the standardized uptake value (SUV) in primary brain tumors on fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) scans. Two groups of patients were studied. Whole-brain glucose cerebral metabolic rates (wCMRs) and SUVs were obtained in 20 normal subjects. Twenty-seven patients with histology-proven malignant primary CNS tumors (high-grade gliomas n=22, primitive neuroectodermal tumors n=3, ependymomas n=2) were also studied. The degree of FDG uptake was assessed by visual inspection and thereafter regions of interest were placed over the lesion, the contralateral cortex and white matter and the whole brain. Average (avg) and maximum (max) pixel values were determined in each site. Based on these measurements, SUV, tumor to cortex (T/C) and tumor to white matter (T/WM) activity ratios were calculated. There was no correlation between wCMRs (4.55±0.36 mg min–1 100 g–1) and wSUVs (5.41±0.43) in the normal subjects (r=0.18, P=0.45). In the second group,17 lesions were described as definitely and seven as probably malignant. However, SUVs in these tumors and in the contralateral cortex were not significantly different. Although the SUVs were generally higher in the tumor than in the contralateral white matter, there was a significant overlap between the values. The range of the SUVs was wide: 2.54–11.8 for the tumors, 2.98–9.96 for the cortex and 1.87–6.76 for the white matter. SUVs in the normal cortex were negatively correlated with blood glucose level at the time of the injection. SUVs in the whole brain and in the cortex were lower in patients previously treated by irradiation, even months after completion of the treatment. No correlation was detectable between any of the SUVs and the age of the patients, tumor type, time post injection, use of dexamethasone, patient weight, dose injected and visual score. With cutoff levels of 1.5 for T max/WM and 0.6 for T max/C, the sensitivity of the activity ratios was 74% and 96% respectively. In conclusion, SUVs do not correlate with CMRs across subjects and appear to be of limited value in characterizing brain tumors. Visual assessment and measurement of the activity ratios currently remain the most reliable methods of analysis.  相似文献   
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