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661.
Gabrilove  JL; White  K; Rahman  Z; Wilson  EL 《Blood》1994,83(4):907-910
Stem cell factor (SCF) and basic fibroblast growth factor (bFGF) are hematopoietic cytokines produced by bone marrow stromal cells. It is known that, although SCF and bFGF have limited clonogenic activity on their own, they can augment colony-stimulating factor (CSF)-mediated progenitor cell growth. Because these factors are both sequestered by stromal cells, we examined their interaction on progenitor cell growth in conjunction with granulocyte-macrophage-CSF (GM-CSF). In this study, we show that clonogenic growth derived from low-density bone marrow cells stimulated by GM-CSF is significantly augmented (P < .001) in the presence of maximal (100 ng/mL) concentrations of SCF in combination with 100 ng/mL of bFGF. When CD34+ cells are used, the synergistic effect of bFGF and SCF for GM-CSF-mediated progenitor cell growth is further increased, resulting in as much as a sevenfold increase in detectable colony-forming units granulocyte-macrophage (P < .001). These data suggest that the synergistic activity of bFGF and SCF is mediated directly on hematopoietic precursors. These observations suggest that bFGF and SCF, concentrated locally on stromal cell surfaces, might interact in concert with other hematopoietic cytokines to regulate stem cell proliferation and differentiation in hematopoietic niches in the bone marrow.  相似文献   
662.
663.
Morocco like several developing countries is undergoing a nutritional transition characterized by the coexistence of nutritional deficiencies and diseases of overweight within the same household. The aim of this work was to determine the prevalence of anemia and overweight (overweight and obesity) among women of reproductive age in two sentinel centers, one rural and one urban area Kenitra. A sample of 128 women was recruited during their visit to the immunization of their preschool children at the health centers. Anthropometric measures and evaluation of hemoglobin were done under the supervision of the medical team of the health center. Women responded to a questionnaire on their demographic and socioeconomic characteristics. The mean age and standard deviation was 28.37?±?6.91 with a minimum of 15 and a maximum of 50?years. Body mass index average was 25.83?±?6.15?kg/m2 and the average hemoglobin was 11.43?±?1.5?g/dl. According to standard threshold of more than 30?kg/m2 and less than 12?mg/dl, respectively, for BMI and hemoglobin, the results show rates of overweight or obesity in 56?% of subjects with a strict obesity prevalence of 15.6?%. Anemia reached a high rate of 60?%. The prevalence of anemia is very high compared with the values of national surveys. Obesity is strongly associated with age. Indeed, older women are at increased risk especially if they have a high number of siblings. The nutrition transition looks serious in the study area. Nutrition education and awareness for physical activity are needed. On the other hand, the strategies against iron deficiency and anemia should identify at-risk populations and advocate a more aggressive nutrition communication.  相似文献   
664.
This study was conducted to evaluate the effects of ivermectin (IVM) with therapeutic dose (injected with 0.56 mg/kg b.wt.) either alone or combined with alpha lipoic acid (ALA) (50 mg/kg b.wt daily) on expression of testicular insulin‐like growth factor binding protein‐3 (IGFBP‐3) and heat‐shock protein A1 (HSPA1)) genes in the testes, as well as on male rat fertility parameters. Results revealed that expression levels of IGFBP‐3 and HSPA1 were significantly increased in testis of the IVM‐treated group relative to the control group. Furthermore, injection of ivermectin showed a significant decrease in serum testosterone level, sperm count, motility %, live sperm% and index weight of reproductive organs, and a significant increase in sperm abnormalities. Moreover, IVM induced oxidative stress and pathological alterations in the testes. Meanwhile, the administration of ALA with IVM prevented testicular damage and improved all previous parameters. We concluded that ivermectin has undesirable effects on male fertility and altered expression of IGFBP‐3 and HSPA1 genes in the testes, while the administration of alpha lipoic acid can ameliorate the adverse effects of ivermectin.  相似文献   
665.
BACKGROUND: Irradiation of platelet concentrates (PCs) with ultraviolet- B (UVB) light inactivates the contaminating white cells and might be an alternative to filtration for the prevention of alloimmunization to HLA antigens and subsequent refractoriness to further platelet transfusions in multiply transfused patients with bone marrow failure. STUDY DESIGN AND METHODS: Patients with hematologic malignancy, mainly acute myeloid leukemia, were prospectively assigned in a random manner to receive either UVB-irradiated or control, nonirradiated PCs. All patients were given red cells that were white cell reduced by filtration. Transfusion efficacy and alloimmunization were assessed by means of corrected count increments, requirement for red cells and PCs, and measurement of lymphocyte-reactive antibodies. RESULTS: UVB-irradiated PCs had a clinical efficacy similar to controls as judged by corrected count increments at 1 to 6 and 12 to 24 hours and by the median requirement for red cell and platelet transfusions. Alloimmunization determined by measurements of lymphocyte-reactive antibodies using both conventional and antiglobulin-augmented lymphocytotoxicity techniques was not abolished in recipients of UVB-irradiated PCs (4/30, 13%) but was less than that in controls (5/20, 25%; p = NS). The mean number of platelet transfusion episodes prior to the occurrence of alloimmunization was greater in the control group (27 vs. 10; p = 0.017). CONCLUSION: In this trial, UVB irradiation did not diminish the clinical efficacy of platelet transfusions. There was a small but nonsignificant reduction alloimmunization, but no difference in refractoriness of the two groups was observed. Larger prospective randomized studies are required to confirm these findings and to compare UVB irradiation with white cell reduction.  相似文献   
666.
667.
BACKGROUND: While prestorage white cell (WBC) reduction by filtration may improve platelet and red cell quality, it also may remove an important anti-bacterial defense mechanism, especially if blood is WBC- reduced shortly after collection. STUDY DESIGN AND METHODS: The question of whether WBC reduction of platelet concentrates and red cells altered bacterial proliferation kinetics in components prepared from deliberately contaminated, freshly collected blood was investigated. Two-unit pools of whole blood were inoculated, at a concentration of approximately one colony-forming unit per mL, with one of 17 bacterial species reported to have caused septicemia in transfusion recipients. Each pool was divided after inoculation, and components were prepared from the 2 units after a 7-hour room- temperature holding period. One unit of each AS-1 red cell or platelet pair was WBC-reduced, and the pairs were then stored for 42 days at 4 degrees C (red cells) or for 10 days at 22 degrees C (platelets). Quantitative bacterial cultures were performed at periodic intervals. RESULTS: In red cells, clinically significant bacterial proliferation occurred in only one instance (Serratia marcescens), and growth was less rapid in the WBC-reduced unit than in the control. Three patterns of growth were seen in platelet concentrates. In four cases, there was rapid proliferation in both test and control units, while on 13 occasions there was minimal replication in either pair. On six occasions, substantial growth was noted in control units, while few or no bacteria could be found in the WBC-reduced units. There was no evidence in either red cells or platelets that bacteria proliferated more rapidly in units that had been WBC-reduced before storage than they did in units in which WBCs were retained. CONCLUSION: Rather than increasing the risk of bacterial proliferation through removal of active phagocytic cells, WBC reduction by filtration before blood storage may act to reduce the likelihood of significant bacterial proliferation, possibly by removal of microorganisms along with WBCs.  相似文献   
668.
669.
THE AETIOLOGY OF IMPETIGO CONTAGIOSA   总被引:1,自引:0,他引:1  
The study egtailed bacteriological investigation of 131 cases of impetigo contagiosa, including the isolation and identification of the offending organisms. The data showed the presence of Staphylococcus aureus in pure culture in 40.5% of the cases, and in mixed growth with betahaemolytic streptococci and other organisms in 47% of the cases. Streptococci came next in frequency and were isolated in pure culture from 9.1% of cases, and in combination with other organisms in 36.7% of the cases. A haemolytic diphtheroid having the characteristics of Corynebacterium pyogenes was isolated in pure culture from one case and in mixed growth in 5.3% of the cases.  相似文献   
670.
Consecutive sections through the epidermis were cut parallel to its surface, and the polyamine (PA) concentration in each section was measured by liquid chromatography. There was a constant decrease in PA concentration (expressed as nmol/mg DNA) from the deepest layer to the more superficial layers. Putrescine showed the greatest increase (+83%) (P less than 0.02). The elevations of spermidine and spermine levels were less marked, respectively +30% (P less than 0.05) and +27% (NS). Proliferating cells in the basal layer possess high polyamine levels and as they mature in the superficial layers their polyamine content decreases.  相似文献   
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