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OBJECTIVE: To assess subjective intensities of pain during supragingival calculus removal employing ultrasonic scaler tips of two different shapes. MATERIAL AND METHODS: Twenty patients were treated using a piezoelectric ultrasonic device (Sirosonic L) and two different scaler tips representing a conventional (Instrument No. 3) and a slim-line style (Perio Pro Line Instrument SI-11) in a split-mouth design. Pain was recorded during calculus removal at intervals of 0.5 s employing an inter-modal intensity comparison. Additionally, a visual analogue scale was used for evaluation directly after the treatment procedure. Treatment time was recorded to assess the efficiency of calculus removal. RESULTS: Pain assessment during treatment showed that the slim-line scaler tip (median pain score: 1.4 [U], maximum: 3.5 [U], minimum: 0 [U]) caused less pain than the conventional device (median pain score: 7.8 [U], maximum: 14.7 [U], minimum: 0 [U]) (p<0.05). These results could be confirmed by the visual analogue scale. Treatment with the slim-line tip took significantly longer than treatment with the conventional tip (p<0.05). CONCLUSIONS: Using slim-line-styled ultrasonic scaler tips for supragingival calculus removal, painful sensations can be reduced compared with conventional ultrasonic devices. Thus, it might be possible to increase the patient's compliance during dental treatment with oscillating instruments.  相似文献   
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OBJECTIVES: Periodontitis is believed to be an independent risk factor of cardiovascular disease (CVD) and to be associated with a moderate systemic inflammatory reaction and hyperlipidaemia. Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an enzyme that has been shown to be a risk factor of CVD and that is involved in the degradation of the phospholipid mediator platelet-activating factor (PAF), a potent mediator of inflammation. MATERIAL AND METHODS: In the present study, we measured concentrations of plasma lipids and plasma activity of Lp-PLA(2) in 32 patients (mean age 43+/-11 years) with moderate-to-severe periodontitis before and 3 months after local treatment. RESULTS: Periodontal therapy resulted in a significant reduction of local inflammation and tissue destruction as reflected in reduced pocket depths and reduced bleeding indices. Pre- and post-treatment plasma lipid levels were (median and range, mmol/l): total cholesterol (C) 5.01 (3.94-7.15) and 4.91 (3.32-8.01); low-density lipoprotein-cholesterol (LDL-C) 3.14 (2.40-4.84) and 2.96 (1.39-5.04); HDL-C 1.27 (0.73-2.17) and 1.25 (0.74-2.55); triglycerides 1.37 (0.48-5.11) and 1.14 (0.38-792). Using the Wilcoxon's rank test, neither parameter showed a significant change. In contrast to the lacking response of plasma lipids, we observed a significant reduction in the activity of Lp-PLA(2). Local treatment lowered the enzyme activity by about 10% from 3.61+/-0.99 to 3.29+/-0.94 micromol/ml/h (mean+/-SD; p<0.001). The pre-treatment values of Lp-PLA(2) and LDL-C significantly correlated with clinical parameters of inflammation and periodontal destruction. CONCLUSION: This study indicates that treatment of periodontitis significantly reduces the serum activity of Lp-PLA(2), which is believed to be an independent cardiovascular risk factor.  相似文献   
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This study investigated the ability and efficacy of an Er:YAG laser with a fluorescence feedback system for caries removal in deciduous teeth. Seventy-nine carious lesions were excavated using a fluorescence-controlled Er:YAG laser. Endpoint of treatment was defined by emission of fluorescence from the dentine surface below the pre-selected threshold level of 7 units and the subsequent termination of Er:YAG laser radiation. Dentine samples were obtained from the cavity floor, and viable counts of both Streptococcus mutans and Lactobacilli, expressed as colony forming units (log CFU), were evaluated. Preparation time was recorded to assess efficacy of the treatment procedure. S. mutans and/or Lactobacilli were found in 25 out of 79 lesions. Regarding the counts for S. mutans and Lactobacilli, the median log CFU was 0 (min, 0; max, 5.5) and 0 (min, 0; max, 6), respectively, with 2.4% of all samples yielding more than 100 CFU S. mutans and 4.8% yielding more than 100 CFU Lactobacilli. In 8 out of 79 cases, laser excavated cavities were not judged being caries-free using the conventional tactile criterion for assessing caries tissue. Focussing on these teeth, the median log CFU was 0 (min, 0; max, 0.5) for S. mutans and 0 (min, 0; max, 1.6) for Lactobacilli. The mean time for treatment was 2.3 +/- 1.2 min. Of the children, 93.8% rated the laser treatment to be comfortable. The study indicates that the fluorescence feedback-controlled Er:YAG laser might be an appropriate device for caries removal in children using the suggested threshold level of 7 units.  相似文献   
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Objective To measure the impact of changes in the fraction of inspired oxygen (FiO2) on systemic and cerebral oxygen supply in gas and liquid ventilated healthy animals.Design Interventional prospective animal study.Setting University research laboratory.Participants Ten healthy, new-born piglets.Interventions Variations in FiO2 during conventional mechanical ventilation (CMV) followed by partial liquid ventilation (PLV) with two different filling volumes of PF 5080 (10 vs. 30 ml/kg).Measurements and results Arterial blood gases were obtained 15 min after changing FiO2 and concentrations of cerebral oxygenated and total hemoglobin were determined with near infrared spectroscopy. During CMV an increase in FiO2 1.0 was associated with a constant rise in PaO2 but only a small increase in the cerebral concentration of oxygenated Hb. Initiation of PLV (at FiO2 of 1.0) caused a rapid drop in PaO2 towards values that were similar to CMV at FiO2 of 0.5. At FiO2 of 0.5 a reduction in oxygenated Hb was found in the 30 ml/kg filling group. Complete filling of the lungs with PFC caused a significant drop in total cerebral Hb concentration.Conclusions According to our data, PLV in healthy lungs should be performed with a FiO2 of 1.0 and a small filling volume to avoid deterioration in cerebral oxygen supply.Financial support: The study was supported by a grant of German Ministry of Education and Research (BMBF Perinatale Lunge-01ZZ9511). NIRO 300 was kindly supplied by Hamamatsu Germany.  相似文献   
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OBJECTIVES: To identify risk and protective factors associated with a history of recurrent pressure ulcers among participants with spinal cord injury (SCI). DESIGN: A mail survey was used to identify factors associated with the presence or absence of recurrent pressure ulcers. SETTING: A large specialty hospital in the southeastern United States. PARTICIPANTS: All participants had traumatic SCI, were nonambulatory, 18 years or older, and had been injured at least 5 years. A total of 826 subjects participated, 633 of whom reported a pressure ulcer history that could be classified as to whether they did or did not have a history of recurrent pressure ulcers. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: History of pressure ulcers was measured by a single item that required participants to classify their history into 1 of 5 options, ranging from never having any pressure ulcers to having almost continuous pressure ulcers, often requiring hospitalization. Those who either never had a pressure ulcer or had them mostly for a short period after SCI onset were classified as nonrecurrent, whereas those who reported at least 1 per year were classified as recurrent. RESULTS: Seventy percent of the participants failed to report recurrent pressure ulcers (never had any or had them only immediately after SCI onset), whereas 13% reported a clear pattern of recurring pressure ulcers of 1 or more per year. Logistic regression analyses suggested several general behaviors were protective for recurrent pressure ulcers, including lifestyle, exercise, and diet. Yet none of the behaviors generally recommended during inpatient rehabilitation specifically to prevent pressure ulcers (eg, skin checks weight shifts) were associated with pressure ulcer history. Only 2 risk behaviors were identified (number of cigarettes smoked, use of medication for sleep), although several proxy variables were related to pressure ulcer history. CONCLUSIONS: Pressure ulcer history is a more viable measure of pressure ulcer outcomes than measures taken at a single point in time (current), over a brief period (eg, 1y), or those relying on critical events occurring at any time since SCI onset (ie, surgeries to repair pressure ulcers). A healthy lifestyle appears to be strongly associated with avoiding pressure ulcers, whereas the efficacy of specific prevention behaviors was not demonstrated. Problem solving and coping strategies should be targets for further research.  相似文献   
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SUMMARY Dysbaric symptoms following ascent from a scuba dive are due to symptomatic nitrogen or air emboli with clear patterns of associated injury. This case report highlights an unusual presentation of dysbaric injury treated successfully with a prostacyclin analogue.  相似文献   
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