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101.
BACKGROUND: Surfactant abnormalities have been implicated in reperfusion injury and respiratory failure in lung transplantation. METHODS: We investigated the efficacy of bronchoscopic administration of a bovine natural lung surfactant extract (Alveofact) to improve gas exchange and lung mechanics after heterologous left lung transplantation in foxhounds (+4 degrees C ischemia for 24 hours, conservation with Euro-Collins solution). Animals received either no surfactant therapy (untreated controls, n = 6) or 50 mg/kg body weight (prior to explantation, only graft) and 200 mg/kg body weight Alveofact (immediately after reperfusion, both lungs, n = 6). After lung transplantation, separate but synchronized ventilation of each lung was performed in a volume-controlled, pressure-limited mode for 12 hours, with the animals prone. Small catheters were inserted into the pulmonary veins of both the graft and the recipient's native lung for separate blood gas analysis. In the control group, marked protein leakage, influx of neutrophils into the alveolar space, and pulmonary edema formation (extravascular lung water; wet/dry ratio) were encountered in the transplanted lung but only to a very minor extent in the recipient's native lung. RESULTS: Lung compliance values and arterial oxygenation progressively deteriorated in the transplanted but not in the native lungs. Pulmonary hemodynamics did not change significantly. Surfactant administration did not significantly influence the development of reperfusion edema, protein leakage, and neutrophil influx into the grafts. However, surfactant restored the surface activity and the gas exchange (PaO2/FIO2 of 201.2 +/- 20.2 mm Hg vs 119.8 +/- 21.7 mm Hg in controls; P <.05) in the transplanted lungs, and compliance was markedly improved in the surfactant-treated animals (18.8 +/- 1.8 mL/mbar vs 11.5 +/- 1.6 mL/mbar in the controls; P <.05). CONCLUSION: Bronchoscopic surfactant administration does not prevent leukocyte influx or vascular leakage but does protect against respiratory failure and improves lung mechanics in single lung transplantation in dogs.  相似文献   
102.
BACKGROUND: The rising prevalence of obesity in children may be due to a reduction in physical activity (PA). OBJECTIVE: Our aim was to study the associations of objectively measured PA volume and its subcomponents with indicators of body fatness. DESIGN: A cross-sectional study of 1292 children aged 9-10 y from 4 distinct regions in Europe (Odense, Denmark; the island of Madeira, Portugal; Oslo; and Tartu, Estonia) was conducted. PA was measured by accelerometry, and indicators of body fatness were the sum of 5 skinfold thicknesses and body mass index (BMI; in kg/m(2)). We examined the associations between PA and body fatness by using general linear models adjusted for potential confounding variables. RESULTS: After adjustment for sex, study location, sexual maturity, birth weight, and parental BMI, time (min/d) spent at moderate and vigorous PA (P = 0.032) and time (min/d) spent at vigorous PA were significantly (P = 0.015) and independently associated with body fatness. Sex, study location, sexual maturity, birth weight, and parental BMI explained 29% (adjusted R(2) = 0.29) of the variation in body fatness. Time spent at vigorous PA explained an additional 0.5%. Children who accumulated <1 h of moderate PA/d were significantly fatter than were those who accumulated >2 h/d. CONCLUSIONS: The accumulated amount of time spent at moderate and vigorous PA is related to body fatness in children, but this relation is weak; the explained variance was <1%.  相似文献   
103.
Tiotropium, a new potent anticholinergic bronchodilator, is excreted mainly by the kidney. To investigate the pharmacokinetics of tiotropium in renal impairment, the authors evaluated the pharmacokinetics and safety after administration of a single dose of intravenous tiotropium 4.8 microg, given as an infusion over 15 minutes in subjects with normal renal function and a wide range of renal impairment based on measured creatinine clearance (normal: > 80 mL/min, n = 6; mild impairment: > 50-80 mL/min, n = 5; moderate impairment: 30-50 mL/min, n = 7; severe impairment: < 30 mL/min, n =6). As expected for a drug excreted predominantly in unchanged form by the kidneys, tiotropium plasma concentrations increased as renal impairment worsened, with mean values of 55.5 (16.2 percent geometric coefficient of variation [%gCV]), 77.1 (20.1 %gCV), 101 (29.8 %gCV), and 108 (27.3 %gCV) pgh/mL for AUC(0-4h) in the normal renal function and the mild, moderate, and severe renal impairment groups, respectively. The percentage of tiotropium dose excreted unchanged in the urine decreased from 60.1% of dose (17.7 %gCV) to 59.3% (14.4 %gCV), 39.9% (34.5 %gCV), and 37.4% (10.2 %gCV) in the normal renal function and the mild, moderate, and severe renal impairment groups, respectively. Plasma protein binding of tiotropium did not significantly change in the renal-impaired subjects. Two subjects with normal renal function experienced headache 10 hours after the infusion, which was mild and transient. No adverse events occurred in subjects with renal impairment. There were no clinically relevant changes in blood pressure, pulse rate, 12-lead ECG, physical examination, hematology, or clinical chemistry, compared with baseline values, in any subject after intravenous administration of tiotropium. Tiotropium should only be used in patients with moderate to severe renal insufficiency if the potential benefit outweighs the potential risks.  相似文献   
104.
105.
PURPOSE: Long lesions remain a challenging task in interventional cardiology, with a high propensity of restenosis, especially within the stented segment. Although intracoronary gamma-radiation has been proved to reduce diffuse in-stent restenosis in long lesions, such an effect remains to be determined using beta-radiation. METHODS AND MATERIALS: Of 1098 consecutive patients at 46 European centers treated with localized beta-radiation ((90)Sr, Novoste Beta-Cath System), 139 patients (mean age 61.5 +/- 10.7 years, 84% male, 22% with diabetes mellitus) with lesions treated using a >40-mm source length underwent radiation using a single 60-mm source train (34%) or a stepping/pullback procedure with a 30-mm (12%) or 40-mm (87%) source length after conventional interventional procedures. The mean lesion length was 35.3 +/- 17.9 mm. RESULTS: Technical success was achieved in 96% of cases. Geographic miss was noted in 9 patients (6.5%). The reference (placebo) group was obtained from the Washington Hospital Center for In-Stent Restenosis Trial (WRIST) and the WRIST Trial for long lesions (LONG WRIST) studies by selecting the cases (94 patients) that required a dummy source length >/=13 seeds (or >51 mm in length). Statistically significant improvement was noted in late angiographic restenosis (34.7% vs. 76.5%, p <0.0001), target vessel revascularization (14.9% vs. 60.6), and major adverse cardiac events (i.e., death, myocardial infarction, or total vessel revascularization) (17.9% vs. 64.9%, p <0.0001) at 6 months in reference to the nonradiation group. CONCLUSION: This subanalysis from the Radiation in Europe with Novoste study confirms the safety and efficacy of beta-radiation combined with conventional interventional procedures in patients with diffuse, long, in-stent restenosis  相似文献   
106.
The clinical characteristics of childhood-onset restless legs syndrome are described. Thirty-two of 538 subjects (5.9%) examined in our sleep disorders center received diagnoses of restless legs syndrome. They were classified based on published criteria into probable (n = 9/32 or 28%) and definite (n = 23/32 or 78%) categories. Apart from an earlier age of diagnosis of the probable group, no differences were found between the two categories. Sleep onset or sleep maintenance insomnia was the most common symptoms, being present in 28 of 32 subjects (87.5%). Inattentiveness was seen in 8 of 32 subjects (25%). Serum ferritin levels were measured in 24 of 32 subjects and were below 50 microg/L in 20 of 24 subjects (83%). A family history of restless legs syndrome was present in 23 of 32 (72%) subjects, with mothers almost three times more likely to be affected than fathers (p = 0.02). We conclude that iron deficiency and a strong family history are characteristic of childhood-onset restless legs syndrome.  相似文献   
107.
Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia manifested by vivid, often frightening dreams associated with simple or complex motor behavior during REM sleep. Patients appear to "act out their dreams," in which the exhibited behaviors mirror the content of the dreams. Management of RBD involves counseling about safety measures in the sleep environment; in those at risk for injury, clonazepam and/or melatonin is usually effective. In this article, the authors present a detailed review of the clinical and polysomnographic features, differential diagnosis, diagnostic criteria, management strategies, and pathophysiologic mechanisms of RBD. They then review the literature and their institutional experience of RBD associated with neurodegenerative disease, particularly Parkinson's disease and dementia with Lewy bodies. The evolving data suggests that RBD may have clinical diagnostic and pathophysiologic significance in isolation and when associated with neurodegenerative disease.  相似文献   
108.
We recently described two novel aryl binding sites of farnesyltransferase. In this study, the cinnamoyl residue was designed as an appropriate substituent for our benzophenone-based AAX-peptidomimetic compound capable of occupying the far aryl binding site.  相似文献   
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110.
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