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301.
Jacalin, a D-galactose-specific lectin from jackfruit, interacts with human IgA and one or two other serum proteins. Incubation of jacalin with fresh human serum was shown to result in activation of the complement system. Therefore the mechanism of complement activation by jacalin was studied. Jacalin was extracted from jackfruit seeds (crude preparation) and purified to homogeneity by affinity chromatography on IgA-Sepharose to yield a pure preparation of jacalin. Both crude and pure jacalin were able to activate complement, accompanied by conversion of C3. Consumption of C1, C4 and C-1-inactivator (C-1-In) indicated involvement of the classical pathway. Aggregated IgG (AIgG) caused partial (38%) and jacalin induced complete consumption of C1-In functional activity. It was found upon Ouchterlony analysis that jacalin forms a precipitation line with purified C-1-In. In addition binding of 125I-C-1-In to jacalin-Sepharose was observed, and this binding was inhibitable by either secretory IgA or D-galactose. Next to binding of jacalin to C-1-In, jacalin was also shown to inhibit the functional activity of C-1-In. These results indicate that jacalin induces complement activation by inhibition of C-1-In function and thereby facilitates the activation of precursor C1 in either the absence or presence of low amounts of C1 activators.  相似文献   
302.
The complement (C)-activating capabilities in human serum of 32 mouse and 10 mouse/human chimeric MoAbs of different isotypes, and their fragments, were tested in vitro. Activation of C via the classical pathway (CP) was performed in 1% factor D-deficient serum in gelatin containing Veronal buffer in the presence of calcium and magnesium (GVB++), while activation of the alternative pathway of C (AP) was assessed in 10% Clq-depleted serum in the presence of 5 mm MgCl2 in GVB++. The C-activating ability of MoAbs was expressed relative to the degree of activation of complement by aggregated IgG for the CP and relative to mouse IgG 1 for the AP. All of seven mouse IgG2a MoAbs were potent activators of the CP. The results of CP activation by IgG1, IgG2b and IgG3 isotypes were different for individual MoAbs. Only three (two IgG 1 and one IgG3) of 32 mouse MoAbs were potent activators of the AP. IgG2a and IgG2b were relatively poor AP activators. There were a few MoAbs which activated both the AP and CP. Of 10 chimeric MoAbs, two IgG1, one IgG2 and one IgG4 were poor or non-activators of the CP. On the other hand, IgG2 and IgG4 were good AP activators. IgG3 was the most potent AP activator. Most of the F(ab')2 fragments were activators of the AP and displayed no activation of the CP. Fc fragments only activated the CP. whereas Fab'did not activate the CP or the AP. These studies suggest that the route of complement activation by class and subclass MoAbs can not always be predicted in advance and based only on their subclass identity.  相似文献   
303.

Background

A short-term study was carried out using guinea pigs to determine the effects of Curcuma domestica on lipid composition in the serum and aorta.

Methods

Animals were given food pellets containing 4% (w/w) powdered rhizome of C. domestica in order to determine its effect on cholesterol, triglyceride and phospholipid levels in the aorta and serum. The animals were fed either a cholesterol free diet or a high cholesterol diet (2% cholesterol, w/w, in food pellet) in order to induce hypercholesterolemia.. After five weeks of this diet treatment, blood and aorta were taken for biochemical analysis and histological studies.

Results

C. domestica in the diet showed no significant effect on the levels of cholesterol, triglyceride and phospholipid in the serum and aorta of the cholesterol free diet animals. However, addition of C. domestica to a high cholesterol diet counteracted increases in the levels of cholesterol, triglyceride and phospholipid in the aorta. Histology studies showed less cholesterol deposits in the aorta of high cholesterol diet animals given C. domestica compared to the high cholesterol diet animals not given C. domestica supplement. C. domestica also had a lowering effect on triglyceride level in the serum of high cholesterol diet animals but showed no effect on serum cholesterol and phospholipid levels.

Conclusion

This study has shown that dietary intake of C. domestica decreased all lipid composition levels in the aorta and also the serum triglyceride level. In addition, C. domestica also reduced cholesterol deposition in the aorta of high cholesterol diet animals.  相似文献   
304.
OBJECTIVES: Use three-dimensional (3D) facial laser scanned images from children with fetal alcohol syndrome (FAS) and controls to develop an automated diagnosis technique that can reliably and accurately identify individuals prenatally exposed to alcohol. METHODS: A detailed dysmorphology evaluation, history of prenatal alcohol exposure, and 3D facial laser scans were obtained from 149 individuals (86 FAS; 63 Control) recruited from two study sites (Cape Town, South Africa and Helsinki, Finland). Computer graphics, machine learning, and pattern recognition techniques were used to automatically identify a set of facial features that best discriminated individuals with FAS from controls in each sample. RESULTS: An automated feature detection and analysis technique was developed and applied to the two study populations. A unique set of facial regions and features were identified for each population that accurately discriminated FAS and control faces without any human intervention. CONCLUSION: Our results demonstrate that computer algorithms can be used to automatically detect facial features that can discriminate FAS and control faces.  相似文献   
305.
该文旨在研究经口腔机器人手术(TORS)治疗头颈部恶性肿瘤的技术可行性、安全性及有效性。对应用daVinci外科机器人治疗的20例患者进行前瞻性研究。纳入标准为成年患者的早期头颈癌,包括口腔癌、口咽癌、下咽癌及喉癌。结果,2例无法充分达到手术部位,手术终止。其他18例术后手术切缘阴性。8例行组织重建。10行单侧颈淋巴清扫,5例行双侧颈清,未行气管切开,术中、术后无并发症。  相似文献   
306.
High bone mass (HBM) can be an incidental clinical finding; however, monogenic HBM disorders (eg, LRP5 or SOST mutations) are rare. We aimed to determine to what extent HBM is explained by mutations in known HBM genes. A total of 258 unrelated HBM cases were identified from a review of 335,115 DXA scans from 13 UK centers. Cases were assessed clinically and underwent sequencing of known anabolic HBM loci: LRP5 (exons 2, 3, 4), LRP4 (exons 25, 26), SOST (exons 1, 2, and the van Buchem's disease [VBD] 52‐kb intronic deletion 3′). Family members were assessed for HBM segregation with identified variants. Three‐dimensional protein models were constructed for identified variants. Two novel missense LRP5 HBM mutations ([c.518C>T; p.Thr173Met], [c.796C>T; p.Arg266Cys]) were identified, plus three previously reported missense LRP5 mutations ([c.593A>G; p.Asn198Ser], [c.724G>A; p.Ala242Thr], [c.266A>G; p.Gln89Arg]), associated with HBM in 11 adults from seven families. Individuals with LRP5 HBM (~prevalence 5/100,000) displayed a variable phenotype of skeletal dysplasia with increased trabecular BMD and cortical thickness on HRpQCT, and gynoid fat mass accumulation on DXA, compared with both non‐LRP5 HBM and controls. One mostly asymptomatic woman carried a novel heterozygous nonsense SOST mutation (c.530C>A; p.Ser177X) predicted to prematurely truncate sclerostin. Protein modeling suggests the severity of the LRP5‐HBM phenotype corresponds to the degree of protein disruption and the consequent effect on SOST‐LRP5 binding. We predict p.Asn198Ser and p.Ala242Thr directly disrupt SOST binding; both correspond to severe HBM phenotypes (BMD Z‐scores +3.1 to +12.2, inability to float). Less disruptive structural alterations predicted from p.Arg266Cys, p.Thr173Met, and p.Gln89Arg were associated with less severe phenotypes (Z‐scores +2.4 to +6.2, ability to float). In conclusion, although mutations in known HBM loci may be asymptomatic, they only account for a very small proportion (~3%) of HBM individuals, suggesting the great majority are explained by either unknown monogenic causes or polygenic inheritance. © 2015 The Authors Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
307.
Aim: To describe the epidemiology of infants admitted to Paediatric Intensive Care (PIC) with acute respiratory failure including bronchiolitis. Methods: Data from all consecutive admissions from 2004 to 2007 in all 29 designated Paediatric Intensive Care Units (PICUs) in England and Wales were collected. Admission rates, risk‐adjusted mortality, length of stay, ventilation status, preterm birth, deprivation and ethnicity were studied. Results: A total of 4641 infants under 1 year of age had an unplanned admission to PIC with acute respiratory failure (ARF), an admission rate of 1.80 per 1000 infants per year. There was a reduced rate of admission with bronchiolitis in South Asian children admitted to PICU, which is not explained by case‐mix. Children born preterm had a higher rate of admission and longer stay, but a similar low mortality. Risk‐adjusted mortality was higher in South Asian infants and the highest in those with ARF (OR 1.76, 95% CI 1.20–2.57) compared with the rest of the PICU population. Conclusion: Acute respiratory failure in infants causes most of the seasonal variation in unplanned admission to intensive care. Socioeconomic deprivation and prematurity are additional risk factors for admission. Fewer South Asian infants are admitted to PICU with a diagnosis of bronchiolitis, but risk‐adjusted mortality is higher in South Asian infants overall.  相似文献   
308.
309.

Objectives

The purpose of this study was to evaluate the prevalence of alveolar bone loss (BL) in healthy children treated at private pediatric dentistry clinics in Brasília, Brazil.

Material and Methods

The research included 7,436 sites present in 885 radiographs from 450 children. The BL prevalence was estimated by measuring the distance from the cementoenamel junction (CEJ) to alveolar bone crest (ABC). Data were divided in groups: (I) No BL: distance from CEJ to ABC is ≤2 mm; (II) questionable BL (QBL): distance from CEJ to ABC is >2 and <3 mm; (III) definite BL (DBL): distance from CEJ to ABC ≥3 mm. Data were treated by the chi-square nonparametric test and Fisher''s exact test (p<0.05).

Results

Among males, 89.31% were classified in group I, 9.82% were classified in group II and 0.85% in group III. Among females, 93.05%, 6.48% and 0.46% patients were classified in Group I, II and III, respectively. The differences between genders were not statistically significant (Chi-square test, p = 0.375). Group composition according to patients’ age showed that 91.11% of individuals were classified as group I, 8.22% in group II and 0.67% in group III. The differences among the age ranges were not statistically significant (Chi-square test, p = 0.418). The mesial and distal sites showed a higher prevalence of BL in the jaw, QBL (89.80%) and DBL (79.40%), and no significant difference was observed in the distribution of QBL (Fisher’s exact test p = 0.311) and DBL (Fisher’s exact test p = 0.672) in the dental arches. The distal sites exhibited higher prevalence of both QBL (77.56%) and DBL (58.82%).

Conclusions

The periodontal status of children should never be underestimated because BL occurs even in healthy populations, although in a lower frequency.  相似文献   
310.
Summary. Factor IX Grifols® is a new high‐purity plasma‐derived FIX concentrate with two specific pathogen elimination steps. Until this study was performed, there were no detailed reports with an adequate number of patients on the clinical evaluation of this product. To determine the efficacy and safety of Factor IX Grifols® for replacement therapy in previously treated patients with severe haemophilia B, this open, multicentre and non‐randomized study included 25 male subjects over the age of 12 with severe haemophilia B. Patients underwent prophylaxis and treatment of bleeding episodes with Factor IX Grifols® for 1 year. The clinical efficacy and safety of this product were assessed. Forty percent of the patients were children and adolescents (12–17 years old). During the 12 months follow‐up, 1 446 000 IU of Factor IX Grifols® were administered in 961 infusions (range 12–83 infusions per patient): 31% for prophylaxis and 69% for bleeding episodes. Only five major bleeding events were reported in two patients. These haemorrhages were successfully treated with a mean of 2900 IU per bleed (range 1500–4000 IU), and 1–3 infusions per bleed. The average time elapsed from the first infusion to resolution of bleeding was 43 h (median). Overall, haemostasis was rated as excellent or good by the investigator in 96% of the infusions. No product‐related adverse events were reported. Factor IX Grifols® is an effective and safe Factor IX concentrate and can be considered as a first line option for replacement therapy in haemophilia B patients.  相似文献   
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