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141.

Background  

Cardiovascular magnetic resonance (CMR) T2-imaging is oedema-sensitive and can detect increased myocardial water content to potentially distinguish acute from chronic myocardial infarction (AMI/CMI). Currently applied conventional black-blood T2-weighted-turbo-spin-echo (T2-BB-TSE)-sequences cause various artefacts which limit their image quality and possibly hamper their interpretation. Image contrast of conventional cine steady-state free precession (SSFP)-sequences partly consists of T2 oedema-sensitive information. We therefore sought to prospectively evaluate SSFP cine-imaging to detect myocardial oedema and differentiate AMI from CMI.  相似文献   
142.
Extracellular adenosine triphosphate (ATP) is a second signal for the assembly of the NLR family, pyrin domain-containing 3 (NLRP3) inflammasome, which form a framework to activate caspase 1, leading to the processing and secretion of the pro-inflammatory cytokine interleukin-1β (IL-1β). The aim of the present study was to investigate the role of the ATP-gated ion channel subtype P2X7 receptor in the inflammasome activation of bovine monocytes. ATP-induced inflammasome assembly in bovine monocytes was shown by caspase-1 activation and the release of IL-1β by LPS/ATP-stimulated bovine cells. The IL-1β release depended on potassium efflux but was independent of reactive oxygen generation of bovine monocytes. Unlike in the human system, a P2X7 receptor antagonist did not block the ATP-induced release of IL-1β of LPS-primed bovine cells. P2X7 mediated pore formation was observed in subsets of bovine T lymphocytes (CD4+>CD8+) but not in monocytes. In addition, ATP and 2-MeSATP but not the high affinity P2X7 agonist BzATP induced calcium influx in bovine monocytes. The data indicate that ROS generation plays no role in the ATP-induced activation of inflammasome in bovine monocytes and that P2X7-mediated pore formation is not necessary for the release of Interleukin-1β.  相似文献   
143.
Abstract There is no consensus on treatment strategies for elderly patients with mantle cell lymphoma (MCL). In this prospective phase II study we investigated whether the poor outcome could be improved, with reasonable toxicity, by prolonging the immunochemotherapy. Ten cycles of alternating cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP)/cytarabine (AraC) with eight doses of rituximab (R) were given as induction. The potential synergism of intermediate-dose AraC and fludarabine was tested in cycles 6-8. Induction was followed by bimonthly rituximab maintenance for 2 years. The median age of the 60 included patients was 74 years, and the Mantle Cell Lymphoma International Prognostic Index (MIPI) was intermediate or high risk in 98% of the patients. The overall response rate was 95% (complete response/complete response unconfirmed 87%). The response of 11 patients improved with cycles 6-8 (R-fludarabine-AraC). Progression-free survival was 70% and overall survival 72% at 4 years, respectively. Treatment related mortality was 2%. Severe infections were rare, with only one grade 4 infection. More dose reductions were needed during fludarabine-containing courses as compared to R-AraC. In 20 patients a transient grade 4 neutropenia without severe infections was recorded during maintenance. In conclusion, elderly patients with MCL can be treated relatively intensively with acceptable toxicity.  相似文献   
144.
Aims: To describe the occurrence of spinal muscular atrophy (SMA) in childhood; to evaluate if any of the genes in the SMA region on chromosome 5q13 correlates with disease severity; to make genotype–phenotype correlations; to evaluate the variability of different disease alleles in carriers and the sensitivity of multiplex ligation-dependent probe amplification (MLPA) for detecting carriers.
Methods: In a population-based study from Western Sweden MLPA was used to determine the copy-numbers of several genes in the SMA region (SMN1, SMN2, BIRC1, GTF2H2 and SERF1A) in SMA-patients and their parents.
Results: We estimated the incidence of SMN1-related SMA in childhood at 1 in 11 800 live births and confirmed the relationship between the number of SMN2 copies and the severity of disease. No other direct relationships were found. All but one of the analysed parents were confirmed as carriers by MLPA analysis. A total of at least 30 different disease alleles were identified and no specific disease allele represented more than 15% of the total.
Conclusion: The childhood incidence of SMA in the Swedish population is around 1 in 12 000 live births and it is unlikely that there is any founder effect involved in SMA in western Sweden.  相似文献   
145.

Background

The population of long-term survivors of childhood brain tumors (BTs) is growing. The aim of our study was to evaluate late-appearing morbidity in BT survivors.

Methods

Patients diagnosed with a BT at the age of 0–15 years between 1970 and 2004, and surviving at least 5 years, were identified from the Finnish Cancer Registry (n = 740). Their late new morbidity ≥5 years after cancer diagnosis was assessed using the Hospital Discharge Registry containing hospitalizations and outpatient visits in specialized health care settings. The morbidity of BT survivors was compared with that of the sibling cohort (n = 3615).

Results

The 5-year survivors had a significantly increased hazard ratio (HR) for endocrine diseases (HR, 14.7), psychiatric disorders (HR, 1.8), cognitive and developmental disorders (HR, 16.6), neurological diseases (HR, 9.8), disorders of vision and hearing (HR, 10.5), and diseases of the circulatory system (HR, 2.7) compared with the sibling cohort. The HRs for disorders of musculoskeletal system (HR, 1.4) and diseases of the kidney (HR, 2.1) were not significantly increased. Radiation treatment did not explain all of the excess morbidity. Female survivors had a higher risk for disorders of vision and hearing (P = .046). Age at diagnosis did not show an effect on HRs. The HRs for endocrine diseases and disorders of vision or hearing loss were highest for survivors treated in the 1980s or later.

Conclusions

Pediatric BT survivors had significant neurocognitive consequences. This, together with the considerable risk for endocrine morbidity, will motivate us to organize systematic follow-up procedures for pediatric BT survivors.  相似文献   
146.
A substantial increase in the prevalence of asthma in the Western world during the last few decades has led to a continuous search for novel factors that might be involved in the development of the disease. We carried out a study to clarify whether there is a relationship between severity of asthma and Chlamydia pneumoniae-specific titres at the group level and whether antibodies to the 60 kDa chlamydial heat shock protein (chsp60) are associated with asthma. A total of 116 (31 men, 85 women) consecutive asthma patients from a chest clinic were recruited and divided into 3 groups according to the severity of the disease: there were 13 asthmatics with severe, 54 with moderate and 49 with mild asthma. In addition, 50 (31 men, 19 women) consecutive blood donors were enrolled to serve as a control group. Sera for the measurements of specific IgG, IgA and IgM antibodies using a microimmunofluorescence test and of chsp60 using an enzyme immunoassay were obtained upon enrolment and also 3-4 months later from the asthma patients. Severe and moderate asthma were found to be strongly associated with elevated IgA antibody levels to C. pneumoniae [odds ratio (OR) 5.58, 95% confidence interval (CI) 1.31-23.72 for severe and OR 5.65, 95% CI 2.05-15.53 for moderate asthma] in a logistic regression model. Furthermore, in women, the occurrence of elevated IgA antibody levels and the age-adjusted geometric mean titres of IgA antibodies were significantly higher among the asthmatics than the controls (p = 0.003 and 0.04, respectively). Antibodies to chsp60 occurred more frequently and in higher concentrations among the asthmatics than the controls, although the differences did not reach significance. In conclusion, severe and moderate asthma were significantly associated with elevated IgA antibody levels to C. pneumoniae suggestive of chronic infection. Antibodies to chsp60 did not prove to be a useful marker of such an infection among the asthmatics studied here.  相似文献   
147.
148.

Background

T2 mapping indicates to be a sensitive method for detection of tissue oedema hidden beyond the detection limits of T2-weighted Cardiovascular Magnetic Resonance (CMR). However, due to variability of baseline T2 values in volunteers, reference values need to be defined. Therefore, the aim of the study was to investigate the effects of age and sex on quantitative T2 mapping with a turbo gradient-spin-echo (GRASE) sequence at 1.5 T. For that reason, we studied sensitivity issues as well as technical and biological effects on GRASE-derived myocardial T2 maps. Furthermore, intra- and interobserver variability were calculated using data from a large volunteer group.

Methods

GRASE-derived multiecho images were analysed using dedicated software. After sequence optimization, validation and sensitivity measurements were performed in muscle phantoms ex vivo and in vivo. The optimized parameters were used to analyse CMR images of 74 volunteers of mixed sex and a wide range of age with typical prevalence of hypertension and diabetes. Myocardial T2 values were analysed globally and according to the 17 segment model. Strain-encoded (SENC) imaging was additionally performed to investigate possible effects of myocardial strain on global or segmental T2 values.

Results

Ex vivo studies in muscle phantoms showed, that GRASE-derived T2 values were comparable to those acquired by a standard multiecho spinecho sequence but faster by a factor of 6. Besides that, T2 values reflected tissue water content. The in vivo measurements in volunteers revealed intra- and interobserver correlations with R2=0.91 and R2=0.94 as well as a coefficients of variation of 2.4% and 2.2%, respectively. While global T2 time significantly decreased towards the heart basis, female volunteers had significant higher T2 time irrespective of myocardial region. We found no correlation of segmental T2 values with maximal systolic, diastolic strain or heart rate. Interestingly, volunteers´ age was significantly correlated to T2 time while that was not the case for other coincident cardiovascular risk factors.

Conclusion

GRASE-derived T2 maps are highly reproducible. However, female sex and aging with typical prevalence of hypertension and diabetes were accompanied by increased myocardial T2 values. Thus, sex and age must be considered as influence factors when using GRASE in a diagnostic manner.

Electronic supplementary material

The online version of this article (doi:10.1186/s12968-015-0118-0) contains supplementary material, which is available to authorized users.  相似文献   
149.
Renal replacement therapy has become available for the majority of patients suffering from severe congenital chronic kidney disease (CKD). Data on the long‐term neurocognitive outcome and the impact of early kidney transplantation (KTx) in this setting is unclear. Neurocognitive outcomes in 15 patients (11 male) with isolated congenital CKD (stage 3–5) requiring KTx at a mean age of 2.8 ± 1.3 were assessed at a mean age of 8.3 ± 1.4 years. Patients underwent neurological examination and testing for neuromotor and neurocognitive function using three independent tests. Pre‐emptive KTx was performed in six patients, and nine patients were dialyzed prior to KTx for a mean period of 11.1 ± 8.6 months. Neuromotor function was abnormal in 8/15 patients. HAWIK‐III showed a global intelligence quotient (IQ) of 93.5 ± 11.4 (P = 0.05) due to a significantly reduced performance IQ of 89.1 ± 11.3 (P < 0.01). In three patients, the global IQ was clinically significantly reduced by >1 SD to <85. In patients with neuromotor dysfunction, performance IQ was lower than in patients with normal neuromotor function (83.8 ± 10.2 vs. 96.2 ± 9.0, P = 0.04). Time on dialysis was inversely correlated to verbal IQ (r = 0.78, P = 0.02). Pre‐emptive KTx and duration of dialysis treatment <3 months was associated with superior neurocognitive outcome. Early (pre‐emptive) KTx results in superior long‐term neurocognitive outcome in children with severe congenital CKD.  相似文献   
150.
The incidence of small renal masses is increasing, as a result of the wide adoption of imaging exams. Their management, however, is complicated, especially in patients with decreased life expectancy or comorbidities. Approximately 20% of small renal masses are benign and, even if malignant, just 10% show aggressive pathological features. Furthermore, competing cause mortality seems to exceed the cancer‐specific mortality in patients aged over 70 years. The role of percutaneous tumor biopsy is still not well defined. All these observations raise the concern as to whether surgery might represent an overtreatment for some cases of small renal masses, calling into question the role of active surveillance. The aim of this review was to evaluate the current evidence pertaining to several hot questions that need to be addressed when contemplating active surveillance for small renal masses. The most relevant publications on this subject available in the literature were selected. Five representative series of active surveillance along with the main related variables were identified. Some relevant items surrounding the field of active surveillance were identified and submitted to an evidence‐based discussion. According to the recent evidence, small renal masses under active surveillance tend to show an indolent course with a low probability of disease progression, the latter being triggered most of the time by a tendency to grow faster. Unfortunately, we are currently unable to predict those few cases with aggressive behavior. According to the current evidence, active surveillance is feasible and safe in elderly and comorbid patients.  相似文献   
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