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21.
Information regarding the inflammatory response in African tick-bite fever (ATBF), an emerging spotted-fever-group rickettsiosis, in international travelers to sub-Saharan Africa, is scarce. Plasma/serum levels of von Willebrand factor (vWF), soluble (s) E-selectin, tumor necrosis factor-alpha, interleukin (IL)-6, interferon-gamma, IL-10, IL-13, IL-8, RANTES, macrophage inflammatory protein-1alpha, and C-reactive protein were studied, at both first presentation and follow-up, in 15 patients with travel-associated ATBF and in 14 healthy travelers who served as control subjects. Our main and novel findings are the following: (1) patients with ATBF had increased levels of vWF and sE-selectin, with a subsequent decrease at follow-up; (2) with the exception of IFN-gamma, levels of cytokines and chemokines were also increased in these patients at the first presentation; and (3) IL-10 and IL-13 tended to increase during follow-up, whereas most of the inflammatory cytokines decreased. The induction of these mediators and the balance between them may be critical both for the regulation of inflammation and for protective immunity in ATBF.  相似文献   
22.
The aim of this study was to describe the sense of security associated with pregnancy and childbirth and to identify factors associated with it. Security was conceptualized in accordance with Kaufmann as a human need and as a human value. The instrument used was a questionnaire with a 4-point scale. The sample consisted of 481 pregnant Finnish women. The response rate was 69%. Rotated factor analysis was carried out and sum variables were produced. The effects of various background variables were calculated using the Kruskal-Wallis test and the Mann-Whitney U-test. The elements creating security were social support, knowledge, prenatal health-care experiences, support from the partner, livelihood, positive stories and, in multiparae, positive previous childbearing experiences. The most salient finding concerning factors related to security was that women who had no pregnancy-related problems in the current pregnancy reported social support, prenatal health-care experiences and support from the partner as security-creating elements more often than women with such problems. This was the only factor related to manifestation of security. The findings suggest that all pregnant women should be assisted by professionals to find security-creating elements in their particular situation to promote and strengthen the sense of security, paying special attention to women with pregnancy-related problems.  相似文献   
23.
We investigated whether certain Actinobacillus actinomycetemcomitans clones occur in elevated proportions in subgingival flora, and if the proportions relate to other bacteria in the samples. A total of 121 A. actinomycetemcomitans strains from 121 patients with periodontitis were serotyped and 60 strains were also genotyped. The 121 strains were divided into three groups and the 60 strains into two groups according proportion of A. actinomycetemcomitans. The samples from the 60 patients with genotyped strains were cultured for five other species. Among the 121 strains, serotype b occurred significantly more frequently in the high- (n = 14, proportions > 5%, mean = 18.09, SD = 20.07%) than low- (n = 49, proportions < or = 0.1%), mean = 0.04, SD = 0.03%) or intermediate-proportion groups (n = 58, proportions > 0.5%, mean = 1.31, SD = 1.24%). Genotype 3 occurred significantly more frequently in samples with low A. actinomycetemcomitans proportions (n = 28, < or = 0.1%, mean = 0.04, SD = 0.03%) than in those with high proportions (n = 32, > 0.1%, mean = 5.70, SD = 14.60%). No differences were seen in the detection frequencies or proportions of the five bacterial species between the samples with low or high A. actinomycetemcomitans proportions. The results indicate that certain clonotypes of A. actinomycetemcomitans may preferentially occur as low proportions, suggesting their controlled growth. Conversely, some serotype b clones may have a competitive advantage in subgingival flora.  相似文献   
24.
Dengue fever (DF) has become common in western travelers to the tropics. To improve the basis for travel advice, risk factors and dengue manifestations were assessed in 107 Swedish patients for whom DF was diagnosed after return from travel in 1998 and 1999. Patient data were compared with data on a sample of all Swedish travelers to dengue-endemic countries in the same years. Only three of the patients had received pretravel advice concerning DF from their physicians. Hemorrhagic manifestations were common (21 of 74 patients) but caused no deaths. Risk factors for a DF diagnosis were travel to the Malay Peninsula (odds ratio [OR] 4.95; confidence interval [CI] 2.92 to 8.46), age 15-29 years (OR 3.03; CI 1.87 to 4.92), and travel duration >25 days (OR 8.75; CI 4.79 to 16.06). Pretravel advice should be given to all travelers to DF-endemic areas, but young persons traveling to southern and Southeast Asia for >3 weeks (who constituted 31% of the patients in our study) may be more likely to benefit by adhering to it.  相似文献   
25.
The effect on behavior of single subtoxic doses (100 and 600 micrograms/kg i.p., i.e. 1/77 and 1/13 of LD50, respectively) of an organophosphorous compound, diisopropylfluorophosphate (DFP), was studied in male Wistar rats. In the open-field test, the lower dose of DFP tended to increase ambulation, while the higher dose showed a trend towards a decrease in ambulation, rearing and frequency of defecation. In the elevated plus-maze, rotarod, elevated bridges and hot plate tests, DFP-treated rats did not differ significantly from the olive oil-treated controls. DFP significantly impaired the performance of rats in the one-trial passive avoidance task and dose-dependently decreased spontaneous locomotor activity for 4 hours after administration. At the doses used DFP only slightly inhibited acetylcholinesterase activity in the blood and different brain areas. The results show that the higher dose of DFP had an inactivating effect on the behavior of rats, while the lower dose did not markedly change their behavioral pattern. Our findings indicate that anticholinesterase compounds, such as DFP, can alter behavior even after single small subtoxic doses.  相似文献   
26.
27.
87 teenagers were included in a 2-year follow-up study on clinical and microbiological conditions of the periodontium. The clinical status was determined according to the Community Periodontal Index of Treatment Needs (CPITN) for subjects under 20 years of age. 59% of the subjects had at least 3 healthy sextants at the baseline and 68% at the 2-year examination. The microbiological conditions were assessed by using direct dark-field microscopy, and the culture of Actinobacillus actinomycetemcomitants (A.a.). Subgingival bacterial samples were taken, 2 for the microscopy and 2 for the culture, from the mesial surfaces of the first molars of each subject. The presence of gingival bleeding after probing was separately recorded from the 2 sites sampled for dark-field microscopy. No gingival bleeding at these 2 sites was found at the 2-year examination in 55% of those subjects who were non-bleeding at baseline, in 46% of the subjects initially with 1 bleeding site and in 13% of the subjects with both sites bleeding at baseline. 55% of the subjects with neither fusiforms, motile rods nor spirochetes at baseline maintained their healthy flora for 2 years. A.a. was recovered in 4 subjects at baseline and in 5 subjects 2 years later, in 3 of them at both examinations. Longer follow-up periods are needed to reveal the significance of the constant recovery of A.a. from the same subjects.  相似文献   
28.
29.
We evaluated the contribution of lifestyle-related factors, calcaneal ultrasound, and radial bone mineral density (BMD) to cervical and trochanteric hip fractures in elderly women in a 10-year population-based cohort study. The study population consisted of 1,681 women (age range 70–73 years). Seventy-two percent (n = 1,222) of them participated in the baseline measurements. Calcaneal ultrasound was assessed with a quantitative ultrasound device. BMD measurements were performed at the distal and ultradistal radius by dual-energy X-ray absorptiometry. Forward stepwise logistic regression analysis was used to find the most predictive variables for hip fracture risk. During the follow-up, 53 of the women had hip fractures, including 32 cervical and 21 trochanteric ones. The fractured women were taller and thinner and had lower calcaneal ultrasound values than those without fractures. High body mass index (BMI) was a protective factor against any hip fractures, while low functional mobility was a risk factor of hip fractures. Specifically, high BMI protected against cervical hip fractures, while low physical activity was a significant predictor of these fractures. Similarly, high BMI protected against trochanteric fractures, whereas low functional mobility and high coffee consumption were significant predictors of trochanteric fractures. Cervical and trochanteric hip fractures seem to have different risk factors. Therefore, fracture type should be taken into account in clinical fracture risk assessment and preventative efforts, including patient counseling. However, the study is not conclusive due to the limited number of observed fractures during follow-up, and the results have to be confirmed in future studies.  相似文献   
30.
OBJECTIVES: To study the effect of a physical activity counseling intervention on instrumental activity of daily living (IADL) disability. DESIGN: Primary care–based, single‐blind, randomized controlled trial. SETTING: City of Jyväskylä, central Finland. PARTICIPANTS: Six hundred thirty‐two people aged 75 to 81 who were able to walk 500 meters without assistance, were at most moderately physically active, had a Mini‐Mental State Examination score greater than 21, had no medical contraindications for physical activity, and gave informed consent for participation. INTERVENTION: A single individualized physical activity counseling session with supportive phone calls from a physiotherapist every 4 months for 2 years and annual lectures on physical activity. Control group received no intervention. MEASUREMENTS: The outcome was IADL disability defined as having difficulties in or inability to perform IADL tasks. Analyses were carried out according to baseline IADL disability, mobility limitation, and cognitive status. RESULTS: At the end of the follow‐up, IADL disability had increased in both groups (P<.001) and was lower in the intervention group, but the group‐by‐time interaction effect did not reach statistical significance. Subgroup analyses revealed that the intervention prevented incident disability in subjects without disability at baseline (risk ratio=0.68, 95% confidence interval=0.47–0.97) but had no effect on recovery from disability. CONCLUSION: The physical activity counseling intervention had no effect on older sedentary community‐dwelling persons with a wide range of IADL disability, although it prevented incident IADL disability. The results warrant further investigation to explore the benefits of a primary care–based physical activity counseling program on decreasing and postponing IADL disability.  相似文献   
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