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61.
62.
Objective The aim of this work was to assess whether psoriasis is associated with phenotype prevalence and altered activity of haptoglobin (Hpt). Background Hpt is a plasma acute‐phase glycoprotein, displaying in humans three phenotypes. Phenotype prevalence or structure modification of Hpt was associated with several diseases. The Hpt main function is to bind and carry to the liver free haemoglobin for degradation and iron recycling. Hpt was recently found able to bind the apolipoprotein A‐I (ApoA‐I), thus impairing its stimulation on the activity of the enzyme lecithin‐cholesterol acyl‐transferase (LCAT). Study design Hpt was isolated from patients with psoriasis vulgaris, and its activity in haemoglobin or ApoA‐I binding and LCAT inhibition was compared with that of normal protein. Methods Two affinity chromatography steps, the first using resin‐coupled haemoglobin and the second anti‐Hpt antibodies, were used to purify Hpt. The protein phenotype was assessed by electrophoresis. Binding experiments were performed by Enzyme‐linked immunosorbent assay with stationary haemoglobin or ApoA‐I, Hpt in solution and anti‐Hpt antibodies for detection of bound Hpt. Standard LCAT assays were carried out in the presence of Hpt purified from patients or healthy subjects. Results Phenotype prevalence of Hpt in psoriasis was not found. After affinity chromatography by haemoglobin, albumin and ApoA‐I were routinely found heavily contaminating only Hpt from normal subjects. Isolated Hpt from patients had lower activity than normal protein in both haemoglobin binding and LCAT inhibition. Conclusions In psoriasis, Hpt displays some structure modification(s), which might be associated with the protein function in the disease.  相似文献   
63.
Osteomyelitis: detection with US   总被引:2,自引:0,他引:2  
Abiri  MM; Kirpekar  M; Ablow  RC 《Radiology》1989,172(2):509-511
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis.  相似文献   
64.
Growth hormone therapy for protein catabolism   总被引:5,自引:0,他引:5  
GH and IGF-I have shown remarkable consistency of effect in a wide range of catabolic conditions. Doses of around 10 IU/m2/day of GH and 80 micrograms/kg/day of IGF-I over short periods of time can improve net protein synthesis and preserve lean body mass. Most studies have reported metabolic endpoints, but favorable clinical effects have included decreased hospital stay and mortality in burns, improved respiratory muscle function in COAD, preserved grip strength post- operatively, and improvements in cardiac and bowel failure. Adverse effects of GH treatment are uncommon and usually related to glycaemic control. GH and IGF-I have differential effects on insulin concentrations--increasing or decreasing concentrations, respectively. The hypoglycaemic effects of IGF-I are dependent on route of administration and are avoided by subcutaneous delivery. Occasional patients have needed to discontinue GH treatment due to hyperglycaemia, although the anabolic action of GH may be partially mediated by increased insulin levels. The co-administration of GH and IGF-I has theoretical advantages by both increasing IGF binding-protein concentrations and balancing glycaemic control. An initial study with combination therapy in calorically-restricted volunteers has shown anabolic effects greater than with either agent alone. This approach requires further study in catabolic patients. There is a need for large, well-designed trials with clinical rather than purely metabolic end-points, and some of these are already underway. Should these studies confirm the early findings, financial considerations will become paramount, although it remains possible that treatment may be self-financing if lengths of hospital admissions are shortened.   相似文献   
65.
SUMMARY A new amoxycillin/clavulanate regimen (‘Augmentin-Duo’ 400/57), to be given orally in two divided doses, has been proposed to overcome the inconvenience of tid dosing. This observer-blind, multicentre study randomised children aged two to 12 years with lower respiratory tract infection to seven days' treatment with either amoxycillin/clavulanate bid at a dose of 25/3.6mg/kg/day (221 patients) or the currently prescribed amoxycillin/clavulanate regimen of 20/5mg/kg/day tid (216 patients). Clinical success (cure) rates at follow up were 81.0% for the bid group and 77.8% for the tid group [difference 3.2%; 95% CI (-4.36, 10.80)], indicating that the regimens were of equivalent efficacy. Both regimens were well tolerated, and there was no statistically significant difference in the incidence of adverse experiences between the two groups. Compliance with study medication was high and similar for both groups (80% compliance: bid 90.0%; tid 87.0%).  相似文献   
66.
67.
The handling of elemental gallium is not thought to be harmful, but this assumption does not consider metal coordination which readily occurs in physiological fluids. The aim of this work was to determine Ga(III) coordination behaviour in simple solutions and assess the effects of complex formation upon skin permeation in vitro. Ga(III) coordination was modelled using metal-ligand stability constants in silico and the permeation of the metal through human and porcine skin determined using four test conditions. Ga(III) was presented to the skin as: (1) Ga3+ ions; (2) a −ve citrate complex (Ganeg); (3) a mixture of +ve and −ve complexes (Gamix) and (4) a mixture of +ve hydroxide complexes (Gapos). The permeability coefficient (Kp) of Ga(III) through human skin increased by almost 2 orders of magnitude when applied as free Ga3+ ions or a Ganeg complex (the two most water soluble complexes), compared to Gamix or Gapos. This trend was not well modelled by porcine skin which proved to be less of a barrier to Ga(III) permeation compared to human skin (Kp = 2 × 10−3 ± 2 × 10−4 cm h−1). Given the significant transdermal bioavailablity of Ga(III) demonstrated by this study, it would appear prudent to re-evaluate the dermal toxicity of this metal.  相似文献   
68.

Objective

To compare oxygen supply options for health facilities in the Gambia and develop a decision-making algorithm for choosing oxygen delivery systems in Africa and the rest of the developing world.

Methods

Oxygen cylinders and concentrators were compared in terms of functionality and cost. Interviews with key informants using locally developed and adapted WHO instruments, operational assessments, cost-modelling and cost measurements were undertaken to determine whether oxygen cylinders or concentrators were the better choice. An algorithm and a software tool to guide the choice of oxygen delivery system were constructed.

Findings

In the Gambia, oxygen concentrators have significant advantages compared to cylinders where power is reliable; in other settings, cylinders are preferable as long as transporting them is feasible. Cylinder costs are greatly influenced by leakage, which is common, whereas concentrator costs are affected by the cost of power far more than by capital costs. Only two of 12 facilities in the Gambia were found suitable for concentrators; at the remaining 10 facilities, cylinders were the better option.

Conclusion

Neither concentrators nor cylinders are well suited to every situation, but a simple options assessment can determine which is better in each setting. Nationally this would result in improved supply and lower costs by comparison with conventional cylinders alone, although ensuring a reliable supply would remain a challenge. The decision algorithm and software tool designed for the Gambia could be applied in other developing countries.  相似文献   
69.

Background

Noise exposure is an inherent part of duty of the aircrew and maintenance staff in the Indian Air Force (IAF). An audiometric survey of IAF personnel was carried out to analyze the prevalence and severity of noise induced hearing loss (NIHL).

Methods

An audiometric study of 1000 IAF personnel of various trades, age and exposure groups were carried out at an operational base. Age related correction of 5 dB per decade was applied for personnel above SO years of age. Personal factors like smoking, blood group and use of ear defenders were analysed for their effect on the prevalence of NIHL.

Result

The study revealed an overall incidence of NIHL of 22.9 % in the personnel with a higher prevalence among the technical trades (26.18 %) as compared to non technical trades (12.5 %). There was a significant increase in prevalence of hearing loss with duration of exposure with 50.8% of personnel above 30 years of exposure having hearing loss. A higher incidence of hearing loss was observed in personnel of blood group O and smokers whereas use of ear defenders was protective.

Conclusion

The study reveals a significantly increased prevalence of NIHL among the technical trades of the IAF personnel. The deleterious effects of smoking and protective effect of regular use of ear defenders are emphasized.Key Words: Noise induced hearing loss, Smoking, Ear defenders  相似文献   
70.
The aim of the study was to determine if high-dose bovine surfactant (Alveofact, initially 100 mg/kg birth weight) would improve oxygenation compared with low-dose surfactant (50 mg/kg birth weight) administered intratracheally within 1 h after birth. Inclusion criteria included gestational age 24–29 weeks and birth weight 500–1500 g, intubation and mechanical ventilation, absence of congenital malformations and bacterial infections. Retreatment was considered if the fraction of inspired oxygen (FiO2) was > 0.4 (dose 50 mg/kg birth weight). The primary endpoint was level of oxygenation (PaO2/ FiO2) 2 h after treatment. The study design was a sequential analysis using a triangular test with alpha = 0.05 and 95% power to detect a 25 % improvement in the endpoint. Oxygenation was improved significantly with high-dose ( n = 42) compared to low-dose treatment ( n =48): 30.9±15.0 kPa (231.5±112.7 mmHg) versus 24.1±15.7 kPa (180.6±118.0 mmHg) (mean ± SD). The survival rate was 83% in both groups and the incidence of pulmonary interstitial emphysema was 33% versus 14% with the high-dose treatment. We conclude that high-dose surfactant significantly improved oxygenation and reduced lung barotrauma. An initial dose greater than 50 mg/kg birth weight of surfactant is required for optimal acute response.  相似文献   
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