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1.
In the oomycete, Phytophthora infestans, mating type is determined by a locus that segregates in a non-Mendelian manner consistent with its linkage to a system of balanced lethals. The significance of this unusual phenomenon was addressed by studying the segregation patterns of DNA markers linked to mating type in the related species, P. parasitica. This was done using loci identified by either RAPD analysis of P. parasitica crosses or by cross-hybridization with RFLP markers linked to mating type in P. infestans. The resulting data revealed that, unlike P. infestans, mating type in P. parasitica was regulated by a locus displaying Mendelian segregation. An improved model for mating-type determination in Phytophthora is presented. Received: 21 October 1996 / 7 April 1997  相似文献   
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OBJECTIVE: Children with hydrocephalus are characterised by slow linear growth in prepuberty, accelerated physical maturation during puberty, and reduced final height. We aimed to study the possible roles of growth hormone, insulin-like growth factor-I (IGF-I), and IGF binding protein-3 (IGFBP-3) in this growth pattern. STUDY DESIGN: One hundred and fourteen patients with shunted hydrocephalus (62 males) aged 5 to 20 years, of whom 17 had spina bifida (six males), and 73 healthy controls (38 males) were studied. Anthropometric measures, body mass index, and body fat mass were assessed and the stage of puberty was determined. Serum growth hormone and plasma IGF-I and IGFBP-3 concentrations were measured. RESULTS: The patients comprised 44 (26 males) who were prepubertal and 70 (36 males) pubertal or postpubertal, while 32 of the controls (19 males) were prepubertal and 41 (19 males) pubertal or postpubertal. The prepubertal children with hydrocephalus had lower IGF-I (p = 0.002) and IGFBP-3 concentrations (p < 0.001) than the controls, and the pubertal children had four times lower basal growth hormone concentrations (p < 0.001). There was a correlation between height SD score and IGF-I levels in the total patient population (r = 0.23; p = 0.01). Peripheral IGF-I concentrations peaked at pubertal stages 2-3 in the female patients and at stage 4 in the controls. The prepubertal patients on antiepileptic treatment, carbamazepine in most cases (73%), had higher IGF-I (p = 0.01) and IGFBP-3 concentrations (p = 0.03) than those who had never been treated with antiepileptic drugs, but still lower IGFBP-3 levels than the controls (p = 0.01). CONCLUSION: Based on these findings, it can be concluded that reduced growth hormone secretion may contribute to the pattern of slow linear growth and reduced final height observed in these patients.  相似文献   
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There is no general agreement on criteria that could be applied to distinguish between orthodontically acceptable and non-acceptable occlusions after the completion of dental development. The aim of the present study was to analyse morphological and functional features that could be used as an index to define an acceptable occlusion in young adults. Three expert panels representing specialists in orthodontics and stomatognathic physiology participated in a modified Delphi method. Each panel responded to a questionnaire concerning the usefulness of various occlusal features, and a set of characteristics was selected on the basis of the responses; thereafter, applicability of the chosen characteristics and their cutoffs for an acceptable-non-acceptable dichotomy was tested clinically. To obtain a consensus level of 100%, the last panel session was completed with a group discussion. Assessments made using the morphological criteria were compared with those made with the dental health component of the Index of Orthodontic Treatment Need. The selected morphological characteristics consisted of overjet, overbite, canine relationship, crossbite, scissors bite and midline deviation. The functional evaluation comprised assessments of discrepancy between the centric relation and the intercuspal position, working- and non-working-side contacts and protrusion contacts. The dental health component and our morphological criteria showed different sensitivity to contact point displacements, interdigitation in buccal segments and increased overbite. This study provides a set of morphological and functional indicators reflecting the current consensus opinion of Finnish professionals. Further studies are needed to analyse the reproducibility of assessment of the characteristics included.  相似文献   
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In Finland, adults born in 1961 or later were progressively entitled to subsidies for dental care from private practitioners during 1986-90, while at the same time having access to care in the Public Dental Service. The aim of this study was to compare the effects of attendance frequency of private dental care on treatment costs and treatment spectrum for the heaviest and lowest users over a period. Three separate cohorts of recipients of reimbursements were formed, using the Social Insurance Register. The highest and lowest cost groups in 1986, 1990, and 1994 were followed up to 1997. Initially, the mean numbers of visits were 1.2-1.3 and 5.2-5.6 and cost Euro 48-53 and Euro 358-379 among low users and heavy users, respectively, in all cohorts. Among the heavy users (the high-cost category) infrequent attendance was related to higher and frequent attendance to lower mean annual costs of care. Among the low users (the low-cost category) the opposite was true. Those who initially belonged to the high-cost category received in 1997 significantly more (P < 0.01) restorative treatment and, to a lesser extent, more (P < 0.01) preventive and periodontal treatment than those belonging to the low-cost category. Frequent dental care seemed to benefit those who received a lot of care. Frequency of attendance was not associated with being a low or a heavy user, indicating rigid check-up routines. The inclusion of simple oral health data would greatly improve the usefulness of the register as an evaluation tool for health-political decisions.  相似文献   
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BACKGROUND: The objective of this study was to evaluate whether the post-neonatal hospitalization and resulting health care costs are increased among in vitro fertilization (IVF) children up to 7 years of age. METHODS: We conducted a population-based cohort study with linkage to a national hospital discharge register including 303 IVF children, born from 1990 to 1995, and 567 control children (1:2) randomly chosen from the Finnish Medical Birth Register and matched for sex, year of birth, area of residence, parity, maternal age and socioeconomic status. The cost calculations were stratified for singleton (n = 152 vs. n = 285) and twin (n = 103 vs. n = 103) status. Main outcome measures were hospitalizations and societal health care costs. RESULTS: The full-sample and singleton analyses showed that IVF children were significantly more frequently admitted to hospital (mean 1.76 vs. 1.07, P < 0.0001; 1.61 vs. 1.07, P = 0.0004, respectively) and spent significantly more days in the hospital (mean 4.31 vs. 2.61, P < 0.0001; 3.47 vs. 2.56, P = 0.0014, respectively) than control children. No differences were detected between IVF and control twins. The costs of post-neonatal hospital care per child were 2.6-fold for IVF singletons, but 0.7-fold for IVF twins when compared with controls. Cost estimation showed 2.6-fold costs for total IVF population in comparison to general population based controls. CONCLUSIONS: The incidence of multiple births increases the utilization of post-neonatal health care services and costs among IVF children in comparison to naturally conceived children. Increased hospitalization and costs were also seen among IVF singletons.  相似文献   
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BACKGROUND: Coenzyme Q10 (CoQ10) has been suggested to be effective in the prevention of migraine, and levels can be quantified with standardized reference ranges. OBJECTIVE: This study documents the prevalence of CoQ10 deficiency in migraine headache and examines the potential effectiveness of supplementation. METHODS: We assessed patients attending a tertiary care center with frequent headaches for CoQ10 deficiency. We recommended patients with low CoQ10 levels begin supplementation with CoQ10 as part of their multidisciplinary treatment plan. We assessed response to treatment including correction of CoQ10 deficiency, overall headache improvement, and headache disability. RESULTS: CoQ10 was measured in 1550 patients (mean age 13.3 +/- 3.5, range 3 to 22 years). The mean total CoQ10 level was 0.60 +/- 0.20 microg/mL (range 0.21 to 1.77 microg/mL). Of these patients, 32.9% were below the reference range. Patients with low CoQ10 were recommended to start 1 to 3 mg/kg per day of CoQ10 in liquid gel capsule formulation. In a subset of patients who returned for timely follow-up (mean, 97 days), the total CoQ10 level improved to 1.20 +/- 0.59 microg/mL (P < .0001), while the headache frequency improved from 19.2 +/- 10.0 to 12.5 +/- 10.8 (P < .001) and headache disability assessed with PedMIDAS improved from 47.4 +/- 50.6 to 22.8 +/- 30.6 (P < .001). CONCLUSIONS: Deficiency of CoQ10 may be common in pediatric and adolescent migraine. Determination of deficiency and consequent supplementation may result in clinical improvement. Further analysis involving more scientifically rigorous methodology will be required to confirm this observation.  相似文献   
10.
Aims/hypothesis: Coeliac disease is more prevalent among patients with Type I (insulin-dependent) diabetes mellitus and coeliac disease-related antibodies have been reported to increase in frequency in their first-degree relatives. Our aim was to find out if coeliac disease is more common among siblings of children with Type I diabetes than in the normal population. Methods: IgA endomysium antibodies were measured by indirect immunofluorescence in 550 subjects (mean age 11.8 years, range 3.1–26.9 years) with a sibling with Type I diabetes. We performed jejunal biopsy on as many subjects with positive antibodies as agreed. HLA-DQB1 genotyping was done in 427 subjects. Results: Endomysium antibodies were positive in nine subjects (1.6 %). Jejunal biopsy was diagnostic for coeliac disease in five out of seven patients. An additional patient with coeliac disease, one already on a gluten-free diet, was identified by questionnaire. The prevalence of coeliac disease was 1.1 %. Five of six patients with coeliac disease had HLA-DQB1*02 allele, compared with 118 of 421 of those without coeliac disease (p = 0.009). The sixth patient was positive for HLA-DQB1*0302 allele, which was also found in 241 of 421 of those without coeliac disease (p = 0.4). Conclusion/interpretation: We found the prevalence of coeliac disease among siblings of children with Type I diabetes to be similar to figures reported from recent population-based studies and to be correlated with the prevalence of coeliac disease associated HLA-DQB1 alleles. We propose that routine screening for coeliac disease among all first-degree relatives of patients with Type I diabetes is not warranted. [Diabetologia (2001) 44: 1051–1053] Received: 11 January 2001 and in revised form: 27 April 2001  相似文献   
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