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1.
This prospective clinic-based study evaluated the pretreatment periodontal status of the orthodontic patients seen at the University College Hospital, Ibadan, Nigeria, and assessed the relationship between dental aesthetic index (DAI) scores and periodontal status according to community periodontal index of treatment needs (CPITN) scores. One hundred forty five patients-70 (48.3%) males and 75 (51.7%) females from 6 to 45 years (mean 15.8 +/- 7.5)-were seen. World Health Organization (WHO) guidelines were followed in the examination and reporting of the periodontal status, and DAI scores were assessed based on WHO guidelines. The chi-square test was used to determine the association between the DAI and the CPITN scores. Most patients were in the 6-15 (55.9%) or 16-25 (35.9%) age groups. Based on the WHO preferred cumulative calculations of treatment need (TN), 35.2% of the patients had TN 0, 64.9% had TN 1, 24.9% had TN 2, and only 0.7% had TN 3. The relationship between DAI scores and periodontal treatment needs was not statistically significant (P >.05). Although many patients were yet to attain the WHO goal of no more than 1 sextant affected by bleeding or calculus at the age of 15, over one third had satisfactory periodontal health.  相似文献   
2.
The aim of the study was to assess the effect of academic stress on periodontal health. The experimental group consisted of 22 final year dental students preparing for a major final BDS examination. The control group was made of 29 first year dental clinical students who were not preparing for any examination. Informed consents were obtained from all the students who participated in the study. The study was double blind as the examiners and the students were not aware of the aim of the study at the examination stage. The baseline measurements of Oral Hygiene Index (OHI) and Gingival Index (GI) were done 6 weeks prior to the commencement of the final BDS examination for both the experimental and the control groups. Statistical significant differences were observed in the two indices at final reading, between experimental and control groups while the baseline scores for the indices revealed no statistical significant differences. The results indicate that non-demonstrable factors like psychosocial stress represent a risk indicator for periodontal disease and these should be addressed in periodontal patients before and during treatment.  相似文献   
3.
Asymptomatic hospital visits have been generally accepted as health behaviour that should be encouraged, although some factors have been identified as factors affecting compliance and attendance. A three years prospective study of the pattern of dental clinic attendance of children seen at the University college Hospital Ibadan was carried out between January 2001-December 2003. A total of 875 children comprising of 421 (48.1%) males and 454 (51.89%) females formed subjects for the study. Results showed that the modal age of presentation was 6-10yers. 88.8% of the children had symptomatic visits while 11.2% had asymptomatic visits and dental caries and its sequel were the frequently diagnosed symptoms. 67.8% of the symptomatic cases required extraction of their badly broken down teeth due to their late presentations at the clinic. Over 80% of the children with asymptomatic visits required only oral prophylaxis. In conclusion, an early age at presentation and asymptomatic visits are health behaviours that should be encouraged through regular dental health education to parents especially mothers.  相似文献   
4.
To assess the prevalence of some of the occlusal anomalies in Ibadan, Nigeria, an epidemiological survey of 644 secondary school children aged 12-18 years (mean age, 14.73 +/- 1.17 S.D.) was done. The sample consisting of 341(53%) males and 303(47%) females was randomly selected. About 66% were from the middle social class while 34% belonged to the working class. Scissors bite recorded the highest prevalence (6.7%) and cross bite was next with 2.2%. No statistically significant associations were found between the occlusal anomalies and socio-economic class (p > 0.05). No statistically significant gender differences were found in relation to the anomalies (p > 0.05). The prevalences of the occlusal anomalies studied were generally lower than those among northern Nigerian children.  相似文献   
5.
The objective of this study was to determine the prevalence of malocclusion among predominantly Yoruba adolescents in Ibadan, Nigeria, and to compare the results with those of other authors. The sample for this epidemiological survey comprised 636 secondary school students, (334 [52.5%] boys and 302 [47.5%] girls), aged 12-17 years (mean age, 14.72 +/- 1.16 SD). The subjects were randomly selected, and none had received previous orthodontic treatment. Occlusal anteroposterior relationships were assessed based on the Angle classification. Other variables examined were overjet, overbite, crowding, and midline diastema. The results showed that about 24% of the subjects had normal occlusions, 50% had Class I malocclusions, 14% had Class II malocclusions, and 12% had Class III malocclusions. Over 66% had normal overbites, and 14% and 9% had increased and reduced values, respectively. Overjet relationship was normal in 66%, increased in 16%, and decreased in 8%. Crowding was observed in 20% of the subjects and midline diastema in 37%. No statistically significant differences were observed for any occlusal variables (P > .05). Class I malocclusion is the most prevalent occlusal pattern among these Nigerian students. Different patterns of Class II and Class III might be present for the dominant ethnic groups in the country. Therefore, a survey of the occlusal pattern in southeastern Nigerians (Ibo ethnic group) would appear to be worthwhile.  相似文献   
6.
Double and congenitally missing teeth are known to be commoner in the primary dentition than the permanent. The knowledge of this trait in the permanent dentition in Africa is still poor. This paper describes the clinical findings in a pair of monozygotic Nigerian twins. This illustrates the claims of genetic basis of such conditions, which have been reported severally in developed parts of the globe but not much among the indigenous Nigerian Negroid population especially involving the permanent dentition.  相似文献   
7.
BACKGROUND: Optical penalization (OP) has previously been shown to successfully maintain vision in amblyopic eyes of older children when patching compliance is poor and when vision decreases once patching is discontinued. This study shows that the final vision in optically penalized eyes is often better than the vision obtained after patching alone. SUBJECTS AND METHODS: During the 5-year period from January 1992 to February 1997, 28 children aged between 3.7 and 8.2 years (average age, 6.5+/-1.1 years) were optically penalized for an average of 1.5+/-0.75 years. The maximum length of penalization was 3.3 years, whereas the minimum time was 6 months. There were 21 children with strabismic amblyopia and 7 children with anisometropic amblyopia. All 28 children had worn a patch to achieve their best visual levels and then had shown a loss of best vision when occlusion was stopped. Patching was usually resumed and continued until the previous best vision was obtained; at this point OP was started to "maintain" vision. Eighteen of the 28 children have discontinued penalization and have been followed up an average of 1(1/2) years. RESULTS: Twenty-six (93%) of the 28 patients showed an increase in best vision from that found at the conclusion of patching, and 2 patients maintained their vision at the initial level. The average visual acuity at the start of penalization was 20/50 (0.42+/-0.11 logarithm of the minimum angle of resolution [log MAR]). Final average visual acuity was 20/27 (0.15+/-0.12 log MAR). The average increase in vision was nearly 3 lines or 0.27+/-0.12 log MAR. CONCLUSION: OP alone (without the use of pharmacologic agents such as atropine) not only maintains vision after patching therapy, but also appears to improve the final visual outcome.  相似文献   
8.
目的:筛选一株优良的抗生素产生菌。方法:通过人为诱变来动摇产生菌原有的严密控制机制。结果:得到一种抗生素生物合成能力异常的突变株。结论:此方法可过量合成人们所期望的抗生素。  相似文献   
9.
目的:考察盐酸特拉唑嗪胶囊的稳定性。方法:通过影响因素(强光照射、高温、高温),加速和留样考察实验,以含量为测定指标,考察胶囊的含量变化。结果:在温度40℃、60℃、光照3500LX及RH75%等因素影响下,胶囊的含量无明显变化。结论:在25℃时,通过经典恒温加速试验推测盐酸特拉唑嗪胶囊的失效期为2年。  相似文献   
10.
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