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71.
Fatty acids, alcohols, and mycolic acid cleavage products were determined for 13 ATCC strains and 24 clinical isolates, which were initially identified by biochemical and growth characteristics as the Mycobacterium terrae complex. The clinical isolates were also analyzed by partial sequencing of the 16S rRNA gene, which divided them into five genetic entities, M. triviale (three strains), M. terrae (four strains), M. nonchromogenicum sensu stricto (seven strains), Mycobacterium sp. strain MCRO 6 (seven strains), and Mycobacterium sp. strain 31958 (one strain). After acidic methanolysis, secondary alcohols were a characteristic feature in all members of the M. terrae complex but M. triviale. In addition to the prominent secondary alcohols, 2-octadecanol and 2-eicosanol, two previously unidentified alcohols, 2-(8,15-dimethyl)docosenol and 2-(8,17-dimethyl)tetracosenol, were detected in M. nonchromogenicum, Mycobacterium sp. strain MCRO 6, and Mycobacterium sp. strain 31958. Only 2-(8,17-dimethyl)tetracosenol was detected in trace amounts in M. terrae. Genetic differences were associated with differences in phenotypic characteristics, including growth at 42°C and pyrazinamidase production. Based on fatty acid and alcohol composition and biochemical and genetic characteristics, M. nonchromogenicum and Mycobacterium sp. strains MCRO 6 and 31958 were found to be a closely related group, named the M. nonchromogenicum complex. Detected genetic variations associated with phenotypic characteristics may indicate further species separation of this complex. In conclusion, the results of gas-liquid chromatography fatty acid analysis, combined with those of a Tween 80 test, enable identification of the species of the M. terrae complex and their separation from other nonpigmented slowly growing mycobacteria.  相似文献   
72.
Occurrences of legionellae and nontuberculous mycobacteria were followed in water systems of a tertiary care hospital where nosocomial infections due to the two genera had been verified. The aim was to examine whether their occurrence in the circulating hot water can be controlled by addition of a heat-shock unit in the circulation system, and by intensified cleaning of the tap and shower heads. One hot water system examined had an inbuilt heat-shock system causing a temporary increase of temperature to 80 degrees C, the other was an ordinary system (60 degrees C). The heat-shock unit decreased legionella colony counts in the circulating hot water (mean 35 cfu/l) compared to the ordinary system (mean 3.6 x 10(3) cfu/l). Mycobacteria constantly present in the incoming cold water (mean 260 cfu/l) were never isolated from the circulating hot water. Water sampled at peripheral sites such as taps and showers contained higher concentrations of legionellae, mycobacteria, and mesophilic and Gram-negative heterotrophs than the circulating waters. The shower water samples contained the highest bacterial loads. The results indicate the need to develop more efficient prevention methods than the ones presently used. Prevention of mycobacteria should also be extended to incoming cold water.  相似文献   
73.
Abstract: The modulation of cardioventilator effects of thyrotropin-releasing hormone (TRH) by histaminergic mechanisms was studied in anaesthetized rats pretreated with histamine receptor antagonists. TRH (1–10. nmol/kg) into the lateral cerebral ventricle dose-dependently elevated mean arterial pressure, heart rate and stimulated respiration. The respiratory stimulating effect of TRH remained unchanged after pretreatments with histamine H1-receptor antagonist diphenhydramine or H2-receptor antagonists cimetidine and ranitidine, while the TRH-induced hypertension and tachycardia were attenuated by cimetidine. This antagonism was not due to an interation between TRH and cimetidine at their central binding sites, since there was no displacement of [3H]MeTRH binding in the presence of cimetidine nor did TRH displace [3H]cimetidine in rat brain homogenates. Inability of diphenhydramine to modify the cardiovascular effects of TRH indicates that these effects are not due to histamine liberation, as cardiovascular stimulation after central administration of histamine is mainly mediated via H1-receptors. The antagonism of the cardiovascular responses to TRH by cimetidine was not due to blockade of H2-receptors, since another potent H2-receptor antagonist ranitidine was unable to affect the cardiovascular effects of TRH. Therefore, we suggest that cimetidine exerted antagonism of TRH by some non-specific action.  相似文献   
74.
The purpose of the current study was to assess speech aerodynamics and nasal acoustic energy during a follow-up period of 12 months in patients having undergone microvascular free flap reconstruction after tumor ablation from the oral cavity or oropharynx, usually followed by radiotherapy. Velopharyngeal function was assessed in terms of velopharyngeal orifice size by a pressure-flow measurement technique as well as by determining the instrumental correlate of perceived nasality (i.e., nasalance) during speech production. Velopharyngeal closure and nasalance were estimated to be adequate before operation both in oral cavity and oropharyngeal cancer patients. After the operation, at the group level, the oral cavity patients showed adequate velopharyngeal closure and nasalance. In contrast, the postoperative velopharynx orifice size was significantly bigger in the oropharyngeal cancer patients as compared with the oral cavity patients 6 months after operation. However, based on average aerodynamic as well as the nasalance data, the impairment of velopharyngeal function was not regarded clinically significant at the group level in either group of patients. The present treatment protocol served to maintain the prerequisites for normal or close to normal speech physiology.  相似文献   
75.
BACKGROUND: The pharmacokinetics of oxycodone (13-hydroxy-7,8-dihydrocodeinone) has been studied in adults and in children who are older than 6 months but there is no information on the disposition of oxycodone in neonates and young infants. The aim of this study was to study the pharmacokinetics of oxycodone in infants varying in age from 0 to 6 months. METHODS: Twenty-two infants undergoing surgery were given postoperatively an intravenous bolus of 0.1 mg.kg(-1) of oxycodone hydrochloride. Ten of the patients were younger than 1 week (group 1), six from 1 week to 2 months (group 2) and six from 2 to 6 months (group 3). Plasma samples were collected for the analysis of oxycodone concentrations up to 24 h. Pharmacokinetics were characterized by noncompartmental methods. RESULTS: The median (range) values for the clearance (Cl) were 9.9 (2.3-17.2), 20.1 (3.7-40.4) and 15.4 (14.8-80.2) ml.min(-1).kg(-1) in the above three groups. The values for volume of distribution at steady-state were 3.3 (1.9-4.7), 5.6 (1.3-8.5) and 3.2 (1.8-6.0) l.kg(-1) and for elimination half-life (t(1/2)) 4.4 (2.4-14.1), 3.6 (1.6-11.6) and 2.0 (0.8-3.9) h, respectively. Both Cl (r = 0.46) and half-life (r = -0.46) were correlated to the age of the patient (P < 0.05). There were 13 patients who were on mechanical ventilation at the time of oxycodone administration. None of the spontaneously breathing infants had hypoventilation which required assistance during the study. CONCLUSIONS: The values for Cl and t(1/2) varied greatly between the subjects. This variability was most pronounced in the two youngest groups. Routine dosing of oxycodone in young infants may be dangerous. The dose of oxycodone must be titrated individually.  相似文献   
76.
The Work Group of European Nurse Researchers (WENR) has been networking for advancement of nursing research in Europe for 25 years. The most well-known activity of WENR is its biennial conferences organized in all parts of Europe. They have provided a unique opportunity for nurses to come together to discuss nursing research and clinical practice. Recently, WENR has published a position paper in order to reinforce its own and International Council of Nurses, World Health Organization and The Standing Committee of Nurses of the European Union (PCN) aims. The Work Group of European Nurse Researchers recommends that the recommendations of The Council of Europe report be adopted formally by national nurses associations. Future activities of WENR include promotion of infrastructures and research capacities in member countries, and planning of new scientific activities.  相似文献   
77.
OBJECTIVE: The aims of the present study were to evaluate the role of the gap junction protein beta-2 gene (GJB2), encoding connexin 26 (Cx26), in children with moderate to profound prelingual nonsyndromic sensorineural hearing impairment (HI) and to investigate the carrier frequencies of the GJB2 gene mutations in a control population in Northern Finland. METHODS: Mutation analysis was performed by direct sequencing and carrier detection by conformation sensitive gel electrophoresis further confirmed by direct sequencing. RESULTS: Cx26 mutations were found in 15 of 71 (21.1%) (67 families) children with HI. Homozygosity for the mutation 35delG was shown to be the cause of HI in 13 of 15 (86.7%) children. Homozygosity for the M34T genotype was found in one child, and compound heterozygosity for the M34T/V37I genotype was found in another. Five families of those with suspected familial HI (29.4%) and six families out of those with sporadic HI (12.0%) had a homozygous or compound heterozygous mutation. The carrier frequency for the mutation 35delG was 1 of 78 (4 of 313) and that for the M34T was 1 of 26 (12 of 313). CONCLUSION: 35delG/35delG genotype was found to be a significant cause of moderate to profound prelingual nonsyndromic sensorineural HI in Northern Finland. M34T/M34T genotype was seen in only one child, but the carrier frequency of the M34T allele was about three times higher than that of the 35delG mutation.  相似文献   
78.
Phyto-oestrogen database of foods and average intake in Finland   总被引:1,自引:0,他引:1  
Information on phyto-oestrogen intake in various populations has been scanty until now, primarily because data on the content of these compounds in foods were lacking. We report here on expansion of the Finnish National Food Composition Database (Fineli) with values for the plant lignans matairesinol and secoisolariciresinol and the isoflavones daidzein and genistein. The values, expressed as aglycones, were based on food analyses (mainly GC-MS) or imputed from analytical data for 180 foods for lignans and 160 foods for isoflavones; additionally, over 1000 values were derived from the recipe database of Fineli. Average intake of these phyto-oestrogens was calculated using food consumption data of the National Dietary Survey FINDIET 1997, which was carried out in a random sample of the adult population in five areas in Finland. The dietary data were collected by 24 h recall =2862). The mean lignan intake was 434 (standard deviation (SD) 1575) microg/d and the mean isoflavone intake was 788 (SD 673) microg/d. Women had a higher lignan density (microg lignans/MJ) in their diet than men (P<0.05). Men had a higher mean daily isoflavone intake, 902 (SD 368) microg, than women, 668 (SD 963) microg (P<0.05). The sources of lignans were many: seeds, cereals, fruit, berries and vegetables. The main sources of isoflavones appeared to be processed meat products/sausages containing soya as an ingredient, and legumes as such. The average intake of lignans and isoflavones in Finland seems to be low, but intake varies throughout the population.  相似文献   
79.
This study examined irrelevant/incorrect answers produced by children with Asperger syndrome or high-functioning autism (7-9-year-olds and 10-12-year-olds) and normally developing children (7-9-year-olds). The errors produced were divided into three types: in Type 1, the child answered the original question incorrectly, in Type 2, the child gave a correct answer, but when asked a follow-up question, he/she explained the answer incorrectly, and in Type 3, the child first gave a correct answer or explanation, but continued answering, which ultimately led to an irrelevant answer. Analyses of Type 1 and 2 errors indicated that all the children tried to utilize contextual information, albeit incorrectly. Analyses of Type 3 errors showed that topic drifts were almost non-existent in the control group, but common in the clinical group, suggesting that these children had difficulties in stopping processing after deriving a relevant answer. LEARNING OUTCOMES: The reader becomes aware of the different instances which may lead to the irrelevance of answers and get knowledge about features of answers of children with AS/HFA.  相似文献   
80.
The aim of this study was to measure the quality of children's dental healthcare from the oral health records of 10-year-olds and from the numbers of children in risk groups. The focus was on dental healthcare and markers of dental records. A representative sample of women expecting their first child was selected in southwestern Finland. Children's dental health, dmft/DMFT = 0, was recorded in 45% of cases with a mean DMFT index of 0.5, and dmft/DMFT &#83 5 in 15% of the children. Late-appearing caries (caries-free at the age of 5 years but caries-existing thereafter) was present in 31% (258/828) of the children. The focus on restorative dental healthcare was appropriate. The use of sweets was documented in 23% of cases and tooth-brushing in 28%. A total of 26% of the children had gingivitis in every segment. The study illustrates that only one of the targets has been fully reached.  相似文献   
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