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1.
The DNA polymerase gene of a novel herpesvirus, vulture herpesvirus (VHV), isolated from an Indian Gyps vulture was completely sequenced using primer walking and transposon insertion strategies. DNA sequencing analysis revealed a single open reading frame (ORF) of 3660 nucleotides (53% G-C content) able to encode 1219 amino acids. Identification was based on a nucleotide sequence identity of approximately 50% to other herpesvirus sequences found in Genbank. Nine motifs were identified that are conserved amongst all known herpesviruses and are found within the 3–5 exonuclease and DNA binding functional domains of the DNA polymerase enzyme. Phylogenetic analysis using Clustal W with neighbour-joining revealed VHV to group within the subfamily Alphaherpesvirinae, more closely related to the avian herpesviruses than to those of other species. Partial sequence data also revealed VHV to contain other genes fundamental to the structure and replication of all herpesvirus genomes. A Real Time PCR Taqman assay specific for the VHV DNA polymerase gene was designed to detect the presence of VHV genomic material in post mortem tissue samples from diseased birds. Positive tissues included the spleen, rectum, thymus, kidney and brain. A herpesvirus specific to vultures may pose a threat to the management of captive breeding programs being established to assist the survival of wild populations of Gyps vultures.  相似文献   
2.

Background  

Extracellular nucleotides (ATP, ADP, UTP and UDP) exert a wide range of biological effects in blood cells mediated by multiple ionotropic P2X receptors and G protein-coupled P2Y receptors. Although pharmacological experiments have suggested the presence of several P2 receptor subtypes on monocytes and lymphocytes, some results are contradictory. Few physiological functions have been firmly established to a specific receptor subtype, partly because of a lack of truly selective agonists and antagonists. This stimulated us to investigate the expression of P2X and P2Y receptors in human lymphocytes and monocytes with a newly established quantitative mRNA assay for P2 receptors. In addition, we describe for the first time the expression of P2 receptors in CD34+ stem and progenitor cells implicating a potential role of P2 receptors in hematopoietic lineage and progenitor/stem cell function.  相似文献   
3.
Background: Percutaneous coronary rotational atherectomy (PCRA) is a potent stimulus of platelet activation and aggregation in vivo. For this reason, many patients undergoing PCRA are treated with platelet glycoprotein (GP) IIb/IIIa inhibitors. However, there is limited data regarding the ability of GP IIb/IIIa inhibitors to reduce ischemic complications of PCRA and no data regarding their effect on long-term survival.Methods: Data on 1138 consecutive patients undergoing PCRA in 5 hospitals in 1998–1999 were pooled and analyzed. Long-term survival was available for all 530 patients treated in 3 of the hospitals.Results and conclusions: GP IIb/IIIa inhibitors were administered to 315 of 1138 (28%) PCRA patients. There was no difference in age, gender or race among patients treated with and without GP IIb/IIIa antagonists. The prevalence of hypertension, diabetes, renal insufficiency and peripheral vascular disease did not differ between groups. Unstable angina was more common among patients treated with GP IIb/IIIa inhibitors (45% vs. 38%, P = 0.036)Patients treated with GP IIb/IIIa inhibitors had lower ejection fractions (50% vs. 55%, P < 0.001) and more 3-vessel coronary disease (24% vs. 16%, P = 0.002). Angiographic success was over 99% in both groups (P = NS). The frequency of major adverse cardiovascular events (MACE) was slightly greater in GP IIb/IIIa inhibitor treated patients (3.8% vs. 2.2%, P = 0.126). At a mean follow-up of 3 years, mortality was 13.3% in the GP IIb/IIIa treated patients and 12% in the untreated patients (P = 0.224). On Cox proportional hazards analysis, treatment with a GP IIb/IIIa inhibitor was not significantly associated with increased survival (Hazard Ratio, 0.81, 95% Confidence Interval, 0.631–1.039, P = 0.098). These data do not indicate a significant association between GP IIb/IIIa inhibitor treatment during PCRA and MACE or survival.Condensed Abstract. There is limited data regarding the ability of GP IIb/IIIa inhibitors to reduce ischemic complications of percutaneous coronary rotational atherectomy (PCRA) and no data regarding their effect on long-term survival. These data do not indicate a significant association between GP IIb/IIIa inhibitor treatment during PCRA and MACE or survival.  相似文献   
4.

Background

Anatomy in medical curricula is typically taught via pedagogy consisting of didactic lectures combined with a practical component. The practical component often includes traditional cadaveric dissection classes and/or workshops utilizing anatomical models, carefully prosected cadaveric material and radiology. The primary aim of this study was to determine if there is an association between attendance at practical classes in anatomy and student assessment outcomes. A secondary aim was to determine if student assessment outcomes were better when students preferentially attended workshops or prosection style practical classes.

Method

We retrospectively examined practical attendance records and assessment outcomes from a single large anatomy subject (approx. 450 students) to identify how attendance at anatomy practical classes correlates with assessment outcome.

Results

Students who scored above the median mark for each assessment attended significantly more practical classes than students who scored below the median assessment mark (Mann Whitney; p?<?0.001), and students who attended more than half the practical classes had significantly higher scores on assessments than students that attended less than half the practical classes (Mann Whitney; P?<?0.01). There was a statistically significant positive correlation between attendance at practical classes and outcomes for each assessment (Spearman’s correlation; p?<?0.01). There was no difference in assessment outcomes for students who preferentially attended more dissection compared to prosection style classes and vice versa (Mann Whitney; p?>?0.05).

Conclusions

Our findings show there is an association between student attendance at practical classes and performance on anatomy assessment.
  相似文献   
5.
The incidences, cooccurrences and epidemiological associations at term of the three common focal macroscopic placental lesions, infarcts, intervillous fibrin plaques (IVFP), and intervillous thrombi (IVT) were investigated as part of a population-based case-control study of small-for-gestational age (SGA) infants. Five hundred and nine placentas from women delivering SGA infants (10th percentile or less for gestational age) and 529 placentas from women delivering infants with birthweights appropriate for gestational age were examined using fixed protocols for identification of macroscopic lesions and microscopic diagnoses. One or more of these lesions were found in 280 placentas (28%), including infarcts in 150 (15%), IVFP in 132 (13%), and IVT in 64 (6%). Macroscopic misidentifications, particularly of IVFP as infarcts, emphasize the need for microscopic diagnoses. There were strong associations between the occurrence of any one type of lesion and cooccurrence of either of the other two, and these associations were site-dependent: between central (nonmarginal) infarcts and central IVFP (P = 0.0023); marginal infarcts and marginal IVFP (P < 0.0001); and between IVT (all central) and marginal infarcts (P < 0.0001) and marginal IVFP (P = 0.012). However, a study of associations between the incidences of placentas bearing each of the three lesions and 31 socio-demographic and pregnancy-related factors showed no associations in common. IVFP, an IVFP variant termed labyrinthine, and IVT did not show any of the independent associations demonstrated between infarcts and SGA, pregnancy-induced hypertension, nonsmoking, age at first pregnancy, and ethnicity. IVFP had no significant associations, and IVT were associated only with male gender. The study has shown that IVFP and IVT do not share the important clinical associations demonstrated for infarcts, but has not identified the pathogenetic factor or factors responsible for the frequent cooccurrence of these lesions. The maternal thrombophilias may have such a role.  相似文献   
6.
It has previously been shown that knee injuries with ACL ruptures may lead to decreased proprioception and that exercise in a normal population, uninjured individuals, may reduce the proprioceptive ability. How proprioception is affected by exercise in patients with ACL deficiency has, to our knowledge, not been studied before. Knee joint proprioception was estimated in 36 patients, 18 males and 18 females, with ACL deficiency by measuring thresholds for detection of slow passive motion before and after a short period of exercise on an ergometer bicycle. In addition, the results were compared with a control group of 24 individuals of the same age. We found trends of enhanced proprioception towards extension in the patient group after cycling, but not in the control group. Towards flexion, both groups showed poorer proprioception after cycling. When difference scores of proprioceptive change in each group were compared, a trend towards different reaction upon cycling between the groups was seen in measurement towards extension from 20° where the patients seemed to improve proprioception, which the controls did not. The results are not conclusive in this pilot study, but the possibility that ACL-deficient patients and controls may not react likewise to cycling, as regards their proprioceptive ability, is discussed.  相似文献   
7.
Background: We assessed the safety and evidence of efficacy of radiofrequency ablation (RFA) for colorectal lung metastases with follow-up to 1 year.Methods: Twenty-three patients had percutaneous RFA for 52 colorectal pulmonary metastases under fluoro-computed tomography (CT). Patients received intravenous conscious sedation and local analgesia with routine hospitalization and monitoring for 24 hours after RFA. Patients had CT scanning at 1 month and then every 3 months, with serum carcinoembryonic antigen assessment monthly and every 3 months.Results: All ablations were technically successful. Tumor diameter ranged from .3 to 4.2 cm. Pneumothorax occurred in 43% (10 of 23) of patients. Six patients required intercostal chest drain placement. Six patients had a second RFA, four for new lesions and two for re-treatment of a previously treated lesion. The median admission was 2.0 days (range, 1–9 days). The median follow-up was 428 days (range, 173–829 days); data are reported to 1 year in this article. Five patients died at 5, 6, 8, 8, and 12 months after RFA from extrapulmonary (n = 1) or widespread (n = 4) disease. One patient developed a malignant pleural effusion at 6 months after RFA. Cavitation was seen in nine treated lesions (17%); all resolved with scar tissue contraction by 12 months. Eighteen patients with CT scan follow-up at 1 year have 40 lesions classified as disappeared (n = 17), decreased (n = 5), stable/same size (n = 4), or increased (n = 14).Conclusions: Percutaneous imaging–guided RFA of multiple colorectal pulmonary metastases is a minimally invasive treatment option with modest morbidity. A significant proportion of patients show good evidence of successful local control at 1 year.  相似文献   
8.
In this article, the role of functional imaging for providing objective evidence that grafts of fetal tissue can survive and form connections in Parkinson’s and Huntington’s disease patients is reviewed. The dissociation between dopamine storage capacity, clinical improvement, and normalization of brain metabolism in PD is discussed, and possible mechanisms underlying the phenomenon of dyskinesias off medication are presented. It is concluded the positron emission tomography and single photon emission computed tomography can provide valuable ancillary information alongside clinical observations but are not currently appropriate modalities for use as surrogate endpoints.  相似文献   
9.
The purpose of this study was to characterise Lyme meningitis (LM) in a Belgian paediatric population and to suggest findings that could allow early distinction from aseptic meningitis (AM). The medical records of patients hospitalised between 1993 and 2000 and with a discharge diagnosis of LM (n=14) or AM (n=16) were retrospectively reviewed. The Kruskal-Wallis test was used to compare data. Of the patients, 16 were identified with AM and 14 with LM, amongst which 7 presented with isolated LM and 7 with associated peripheral facial palsy (PFP). Patients with AM, when compared with LM, complained of more pronounced signs and symptoms of meningitis (fever, headaches, and neck stiffness); they statistically displayed a shorter period of symptoms before admission (1.6 vs 15 days), higher neutrophilic component (mean 56% vs 2.4%), and lower protein levels (mean 0.39 vs 1.12 g/l) on cerebrospinal fluid analysis. In the neuroborreliosis group, the duration of symptoms was shorter and the cerebrospinal protein level was lower in cases of LM associated with PFP compared to isolated LM (mean 1.3 vs 15 days; mean 0.55 g/l vs 1.12 g/l). Conclusions.Our results suggest that some clinical data and laboratory findings may help the physician to diagnose aseptic or Lyme meningitis before completion of serologic testing. LM should be suspected in cases of meningitis with very low CSF neutrophilic counts and high protein levels associated with prolonged duration of symptoms, low grade fever, and absence of pronounced signs of meningitis.  相似文献   
10.
In some rodent strain combinations, allogeneic spleen transplantation induces tolerance spontaneously to itself and to other donor-specific organs. In other combinations, a state of tolerance has been achieved in the weakened immune system of the recipient. The data indicate that if a balance can be achieved between host-versus-graft and graft-versus-host responses, tolerance develops, possibly due to the development of suppressor/regulatory cells. There have been a number of unsuccessful studies in outbred large animals, but none in MHC-defined donor-recipient pairs, and none in which the protocol specifically aimed at inducing tolerance. Spleen transplantation has been performed in approximately 50 humans for a number of reasons, however no clear immunologic advantage has been reported. Graft-versus-host disease (GVHD) was documented in at least 3 patients, and was lethal in one case, despite excision of the donor spleen. The advantages of tolerance over chronic immunosuppressive therapy are so great that a potentially tolerogenic approach such as spleen transplantation would seem worthy of further investigation in a suitable large animal model. Such a study is ongoing at our center.  相似文献   
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