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21.
In the case of the central nervous system or hepatic involvement, the prognosis of neonatal herpes simplex infection remains poor, despite antiviral drugs, presumably effective if given early. We report the case of a neonate with herpes simplex hepatitis, where the course of the illness was unusual with chronic, ultimately fatal, cholestasis. The treatment was not effective, because its administration was delayed, because of high infant C reactive protein level and the absence of clinical maternal genital infection, and because it was interrupted due to misleading information: clinical improvement, negative viral tests and raised herpes IgG antibody titer.  相似文献   
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Following gastrectomy, the longer is a Roux-Y limb constructed to restore digestive continuity the higher the frequency of postoperative symptoms. The aim of this experimental study was to test how the level of the jejunal transection and the length of the Roux limb affect the motility of the constructed limb and in particular the onset and the propagation of activity fronts (AFs). Three months after a distal Roux-en-Y gastrectomy, electromyographic tracings were recorded in six groups of rats grouped according to the level of the transection (20 or 40 cm from the pylorus) and the length of the limb (10, 20 or 30 cm). Animals in which a simple laparotomy or laparotomy + jejunal transection was performed, served as controls. During the interdigestive period, all animals had AFs in the limb which were independent from those recorded in the duodenum. In the limb, the mean time interval between two AFs was shorter (P < 0.01) and more irregular than in controls. An increase in limb length was associated with a lower incidence of completely propagated AFs (P < 0.05) and a higher incidence of irregularly propagated AFs (P < 0.01). When propagation of the AFs was analysed both in the limb and in the jejunum distal to the anastomosis, propagation abnormalities were more frequent. Below the gastrojejunal anastomosis, for an intestinal length of either 20 or 30 cm, the frequency of abnormal AFs was not different when this length was either only a limb or a limb with the 10 cm of distal jejunum below the jejuno-jejunal anastomosis. Interruption of AFs by a meal was irregular in the limb and more rarely observed in the 30-cm than in 10-cm limbs (P < 0.05). Interruption of AFs was shorter than in controls (P < 0.01). In the duodenum and the jejunum proximal to the limb, the interval between AFs was higher than in controls and in the Roux-Y limbs (P < 0.001). Intraluminal concentrations of bacterial strains were not different in the different types of limb while lactobacillus concentrations and pooled concentrations of bacteria were higher than in controls (P < 0.05). No relationship was found between the incidence of myoelectric abnormalities and intraluminal bacterial concentrations. Increasing the length of a Roux-Y limb resulted in more frequent disturbances in AFs in the limb but had no significant consequence on the overall rate of abnormal AFs in the jejunum distal to the transection. Motor response to food intake was also reduced. Motor changes were not related to intraluminal bacterial concentrations.  相似文献   
24.
β-Thalassemia is a genetic disease caused by a defect in the production of the β-like globin chain. More than 200 known different variants can lead to the disease and are mainly found in populations that have been exposed to malaria parasites. We recently described a duplication of four nucleotides in the first exon of β-globin gene in several families of patients living in Nord-Pas-de-Calais (France). Using the genotypes at 12 microsatellite markers surrounding the β-globin gene of four unrelated variant carriers plus an additional one recently discovered, we found that they shared a common haplotype indicating a founder effect that was estimated to have taken place 225 years ago (nine generations). In order to determine whether this variant arose in this region of Northern Europe or was introduced by migrants from regions of the world where thalassemia is endemic, we genotyped the first 4 unrelated variant carriers and 32 controls from Nord-Pas-de-Calais for 97 European ancestry informative markers (EAIMs). Using these EAIMs and comparing with population reference panels, we demonstrated that the variant carriers were very similar to the controls and were closer to North European populations than to South European or Middle-East populations. Rare β-thalassemia variants have already been described in patients sampled in non-endemic regions, but it is the first proof of a founder effect in Northern Europe.  相似文献   
25.

Objective

Folate is involved in the one-carbon metabolism that plays an essential role in the synthesis, repair, and methylation of DNA. We examined whether child??s germline genetic variation in the folate pathway is associated with childhood acute lymphoblastic leukemia (ALL), and whether periconception maternal folate and alcohol intake modify the risk.

Methods

Seventy-six single nucleotide polymorphisms (SNPs), including 66 haplotype-tagging SNPs in 10 genes (CBS, DHFR, FOLH1, MTHFD1, MTHFR, MTR, MTRR, SHMT1, SLC19A1, and TYMS), were genotyped in 377 ALL cases and 448 controls. Log-additive associations between genotypes and ALL risk were adjusted for age, sex, Hispanic ethnicity (when appropriate), and maternal race.

Results

Single and haplotype SNPs analyses showed statistically significant associations between SNPs located in (or adjacent to) CBS, MTRR, TYMS/ENOFS, and childhood ALL. Many regions of CBS were associated with childhood ALL in Hispanics and non-Hispanics (p < 0.01). Levels of maternal folate intake modified associations with SNPs in CBS, MTRR, and TYMS.

Conclusion

Our data suggest the importance of genetic variability in the folate pathway and childhood ALL risk.  相似文献   
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Although numerous reports indicate that patients receiving autotransplants for lymphoma are at increased risk for myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML), the separate contributions of pretransplantation- and transplantation-related therapy are not well characterized. We conducted a case-control study of 56 patients with MDS/AML and 168 matched controls within a cohort of 2 739 patients receiving autotransplants for Hodgkin disease or non-Hodgkin lymphoma at 12 institutions (1989-1995). Detailed abstraction of medical records was undertaken to determine all pre- and posttransplantation therapy, and transplantation-related procedures. In multivariate analyses, risks of MDS/AML significantly increased with the intensity of pretransplantation chemotherapy with mechlorethamine (relative risks [RRs] = 2.0 and 4.3 for cumulative doses < 50 mg/m2 and > or = 50 mg/m,2 respectively; trend over dose categories, P =.04) or chlorambucil (RRs = 3.8 and 8.4 for duration < 10 months or > or = 10 months, respectively; trend, P =.009), compared with cyclophosphamide-based therapy. Transplantation-conditioning regimens including total-body irradiation (TBI) at doses 12 Gy or less did not appear to elevate leukemia risk (RR = 1.3; P =.48) compared with non-TBI regimens; however, a statistically significant increased risk was found for TBI doses of 13.2 Gy (RR = 4.6; P =.03). Peripheral blood stem cells were associated with a nonsignificant increased risk of MDS/AML (RR = 1.8; P =.12) compared with bone marrow grafts. Our data show that type and intensity of pretransplantation chemotherapy with alkylating agents are important risk factors of MDS/AML following autotransplantation. Transplantation-related factors may also modulate this risk; however, the apparent contribution of high-dose TBI requires confirmation.  相似文献   
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Although recent studies have demonstrated associations between nonchromosomal birth defects and several pediatric cancers, less is known about their role on childhood leukemia susceptibility. Using data from the Childhood Cancer and Leukemia International Consortium, we evaluated associations between nonchromosomal birth defects and childhood leukemia. Pooling consortium data from 18 questionnaire-based and three registry-based case-control studies across 13 countries, we used multivariable logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between a spectrum of birth defects and leukemia. Our analyses included acute lymphoblastic leukemia (ALL, n = 13 115) and acute myeloid leukemia (AML, n = 2120) cases, along with 46 172 controls. We used the false discovery rate to account for multiple comparisons. In the questionnaire-based studies, the prevalence of birth defects was 5% among cases vs 4% in controls, whereas, in the registry-based studies, the prevalence was 11% among cases vs 7% in controls. In pooled adjusted analyses, there were several notable associations, including (1) digestive system defects and ALL (OR = 2.70, 95% CI: 1.46-4.98); (2) congenital anomalies of the heart and circulatory system and AML (OR = 2.86, 95% CI: 1.81-4.52) and (3) nervous system defects and AML (OR = 4.23, 95% CI: 1.50-11.89). Effect sizes were generally larger in registry-based studies. Overall, our results could point to novel genetic and environmental factors associated with birth defects that could also increase leukemia susceptibility. Additionally, differences between questionnaire- and registry-based studies point to the importance of complementary sources of birth defect phenotype data when exploring these associations.  相似文献   
30.
Hispanic children have a higher incidence of acute lymphoblastic leukemia (ALL) than non‐Hispanic whites but tend to be diagnosed at older ages. In genome‐wide association studies, Native American ancestry and polymorphisms in six genes have been associated with ALL risk. In multivariable regression models, we investigated whether genomic ancestry, inherited risk SNPs, or acquired somatic alterations were associated with differences in age at diagnosis in Hispanic children with B‐cell ALL. Genome‐wide array data were used to estimate each participant's percent membership in the three Hispanic ancestral populations: Native American, African, and European. Each 20% increase in European ancestry was associated with a six month younger age at diagnosis (95% CI = 0.36–11.6 months, P = 0.037). Correspondingly, each 20% increase in Native American ancestry was associated with a six‐month older age at diagnosis (P = 0.037). Both the TEL‐AML1 translocation and high‐hyperdiploidy were associated with younger age at diagnosis (24.4 months, P = 2.0 x 10?4 and 12.4 months, P = 0.011, respectively), while CDKN2A and IKZF1 deletions were associated with older age at diagnosis (19.7 months, P = 7.0 x 10?4 and 18.1 months, P = 0.012, respectively). No associations with age at diagnosis were observed for RAS mutation, PAX5 deletion or for known heritable risk alleles in IKZF1, CDKN2A, PIP4K2A, GATA3, ARID5B, or CEBPE. Because younger age at diagnosis is associated with improved treatment outcomes for children with ALL, the effect of European ancestry on ALL survival may be mediated by its effect on age at diagnosis, or by proxy, its association with more treatable molecular subtypes of ALL. Am. J. Hematol. 89:721–725, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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