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Autologous bone marrow transplants (BMTs) can repopulate the hematologic system of patients treated with marrow-ablative chemotherapy and/or radiotherapy. However, treatment of the bone marrow graft to eliminate residual tumor cells prior to reinfusion can delay the return of peripheral blood elements, presumably from damage to or loss of hematopoietic stem cells responsible for hematologic recovery. To develop a model predictive of hematologic recovery, we studied the progenitor cell contents of 4-hydroperoxycyclophosphamide (100 micrograms/mL)-purged bone marrow grafts of 40 consecutive patients undergoing autologous BMT at this center. Granulocyte-macrophage colonies (CFU-GM) were grown from all grafts after treatment with this chemotherapeutic agent, but erythroid (BFU-E) and mixed (CFU-GEMM) colonies were grown from only 44% and 33% of the grafts respectively. The recovery of CFU-GM after purging ranged from 0.07% to 23%. The logarithm of CFU-GM content of the treated grafts was linearly correlated with the time to recovery of peripheral blood leukocytes (r = -0.80), neutrophils (r = -0.79), reticulocytes (r = -0.60), and platelets (r = -0.66). The CFU-GM content of purged autologous bone marrow grafts may reflect the hematopoietic stem cell content of the grafts and thus predict the rate of hematologic recovery in patients undergoing autologous BMT.  相似文献   
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We examined the effects of varying incubation conditions on the in vitro activity of 4-hydroperoxycyclophosphamide (4HC). 4HC activity against CFU-GM and against the K562 tumor cell line decreased with increasing the RBC concentration of the incubation mixture. Increasing the concentration of nucleated bone marrow cells in the incubation mixture also decreased the 4HC activity. Evaluation of 53 consecutive patients undergoing autologous bone marrow transplantation (BMT) revealed that the incubation RBC concentration during clinical purging showed a similar effect on CFU-GM recovery. Aldehyde dehydrogenase content of RBCs and nucleated marrow cells appears to be the cause of the inhibition of 4HC activity. Although there was no difference in individual CFU-GM sensitivity to 4HC among normals, previously treated patients undergoing autologous BMT showed significant variability in CFU-GM sensitivity to 4HC. The combined effects of incubation RBC concentration and individual patient 4HC sensitivity appear to account for most of the variability in CFU-GM recovery and speed of hematologic recovery after clinical purging with 4HC.  相似文献   
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We used an in vitro measure of drug activity to predict the efficacy of ex vivo purging of leukemic cells from autologous bone marrow grafts. We previously found that the myeloid progenitor cell (CFU-GM) content of the marrow grafts after ex vivo purging with 4- hydroperoxycyclophosphamide (4-HC) correlates with time to hematologic recovery after autologous bone marrow transplantation in patients with acute nonlymphoblastic leukemia. We observed that variable red blood cell concentration of the bone marrow incubation mixture results in differential cytotoxic activity of 4-HC. The CFU-GM content of the graft after the ex vivo treatment is a measure of this 4-HC activity. We analyzed the disease-free survival of 45 patients with acute nonlymphoblastic leukemia undergoing autologous bone marrow transplantation with 4-HC purged grafts. Patients who relapsed after transplantation had 4.2 +/- 1.1% of graft CFU-GM surviving the ex vivo purge, compared with 1.1 +/- 0.4% for patients who achieved a sustained remission (P = .06). Twenty-three patients with a CFU-GM content after 4-HC purging of greater than 1% of the pretreatment value had an actuarial disease-free survival of 12%, compared to 36% for 22 patients with a less than or equal to 1% CFU-GM content after purging (P = .006). Therefore, percent CFU-GM survival as a measure of 4-HC cytotoxicity identified a group of patients with insufficient purging. Although no randomized clinical trials have documented the need for ex vivo purging, our results suggest that effective bone marrow purging is important for the optimal application of autologous transplantation in the treatment of acute nonlymphoblastic leukemia.  相似文献   
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ObjectiveTo assess the role of oxidative stress on anaemia in pregnancy.MethodsBlood samples were collected from pregnant and non-pregnant women who came for antenatal clinic and medical check at Comprehensive Health Center, Akungba-Akoko and Iwaro General Hospital in Akoko Area of Ondo State, Nigeria. Thick and thin blood films were prepared and used for malaria parasite counts. Haemoglobin level was determined by colorimetric method using Drabkin's solution. Oxidative status was determined using malondiadelhyde level as an indicator of lipid peroxidation, while ascorbic acid and reduced glutathione levels were measured by standard spectrophotometric methods.ResultsMean parasite density was significantly higher in pregnant women than non-pregnant women (P<0.05). Haemoglobin level was significantly reduced in malaria positive pregnant and non-pregnant women than malaria negative (8.3-10.0 g/dL) (P<0.05). The oxidative status indicated that malondialdehyde (MDA) was significantly increased in pregnant [(2.5±0.7) nmol/mL] than non-pregnant women [(1.8±0.1) nmol/mL] (P<0.05), while Vit C and superoxide dismutase (SOD) levels were significantly reduced in pregnant than non-pregnant women(P<0.05). There was an inverse correlation between Hb and MDA levels in pregnant women studied. Positive correlation was observed between the mean MDA level and parasite density (r = 0.53). The Hb level decreased as the parasite density and MDA level increased in pregnant women.ConclusionsThis study shows that oxidative stress, caused by malaria infection could be part of the contributing factors responsible for anaemia in pregnancy.  相似文献   
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AIMS: To study whether drug offenders differ in childhood and in early adulthood from those who only report using illicit drugs. DESIGN: Prospective nationwide birth cohort study. Baseline survey in 1989, follow-up data collection from self-reports, police and military registers in late adolescence and early adulthood. PARTICIPANTS: Two-thousand nine hundred and forty six Finnish boys born in 1981. Information about self-reported drug use at age 18 or police-registered drug offending at age 17-20 was available from 79.3% (n = 2,336) of the subjects. MEASUREMENTS: At age 8, psychopathology was assessed using the parent and teacher Rutter scales and child self-reports (Child Depression Inventory). ICD-10 psychiatric diagnoses at early adulthood according to the military register were based on a medical examination. FINDINGS: Childhood psychopathology did not predict self-reported drug use at age 18. Both conduct and hyperactivity problems at age 8 predicted drug offences at age 16-20. The predictive association with drug offences was strongest with severe level (over 90th percentile cut-off point) of conduct (OR 5.5, 95% CI 2.9-10.5) and hyperactivity problems (OR 5.0, 95% CI 2.7-9.3). Also moderate level of conduct (OR 2.9, 95% CI 1.7-4.9) and hyperactivity problems (OR 3.1, 95% CI 1.9-5.1) predicted drug offending. Having a psychiatric diagnosis in early adulthood associated with both self-reported use (OR 4.1, 95% CI 2.4-6.8) and drug offending (OR 13.2, 95% CI 8.3-21.2). CONCLUSIONS: Drug offending is part of a life-course-persistent deviance, whereas for self-reporters, psychiatric problems arise later in life. Accordingly, the preventive needs, and the age period for intervention are different for boys with divergent illicit drug use involvement.  相似文献   
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Long-term usage of systemic steroids is associated with multiple side effects. One of the major morbidities is due to its effect on bone metabolism leading to bone loss and resulting in skeletal fractures. This study was conducted to determine the effects of inhaled steroids on bone mineral density (BMD) and biochemical bone markers. Twenty-four children with frequent episodic or mild persistent asthma who satisfied the clinical criteria for starting on inhaled corticosteroids (ICS) were enrolled into the study. The BMD scan was done using dual energy X-ray absorptiometry, prior to starting ICS therapy and 6 months later. Biochemical markers of bone metabolism, (i) serum osteocalcin as a bone formation marker, and (ii) urinary deoxypyridinoline (Upd) as a bone resorption marker, were taken prior to ICS treatment and at 2 monthly intervals. The biochemical markers were all taken in the morning. Twenty-four, age- and sex-matched children with mild episodic asthma, not requiring ICS, were used as controls for the BMD measurements. The BMD scan was done upon enrollment into the study and 6 months later. Twenty-four children on ICS and 24 controls completed the study. The subjects were on a mean dose of beclomethasone dipropionate (BDP) 0.4 mg/day. One subject needed a short course of Prednisolone in the early treatment period. None of the controls needed oral steroid therapy. One child in the control group sustained a greenstick fracture after an accidental fall. The mean rate of change of BMD was 1.8% +/- 12.3 in the subjects on BDP. This was lower than the 6.1% +/- 10.6 among the control subjects. However, this difference did not reach statistical significance (P = 0.16). There was a significant increase in serum osteocalcin level after 6 months of BDP treatment from 66.83 +/- 22.71 ng/mL to 81.61 +/- 24.66 ng/mL (P < 0.005). There was a decline in Upd from 36.2 +/- 47.1 nmol/mmol creatinine to 21.4 +/- 6.92 nmol/mmol creatinine. However, this did not reach statistical significance. There was no difference in the statural gain between the subjects on ICS and their controls. This study showed that 6 months of ICS therapy (mean dose 0.4 mg/day) had no significant adverse effect on bone metabolism in asthmatic children.  相似文献   
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The conformations of cyclo(-D-Trp-D-Asp-Pro-D-val-Leu-) in dimethyl sulfoxide-d6 (DMSO-d6) and water were determined using two-dimensional nuclear magnetic resonance spectroscopy and restrained molecular dynamics. Comparisons were made between conformations of the cyclic pentapeptide in both solvents. The NMR study revealed that, while the backbone remained relatively unchanged in both solvents, the side-chains adopted distinctly different orientations in DMSO-d6 vs. H2O. A modeling study, minus NOE constraints, produced a set of low-energy conformers possessing agreement in backbone conformation with the NMR-derived structures; however, lowest-energy conformers did not have this agreement. These results show that different solvents can significantly affect the preferred side-chain conformation of small cyclic peptides in solution. This finding will impact the selection of solvent when determining structures for use as templates in rational drug design.  相似文献   
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