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1.
硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
2.
This report of the North American Pediatric Transplant Cooperative Study summarizes data contributed by 57 participating centers on 754 children with 761 transplants from 1 January 1989 to 16 February 1989. Data collection was initiated in October 1987 and follow-up of all patients is ongoing. Transplant frequency increased with age; 24% of the patients were less than 5 years, with 7% being under 2 years. Common frequent diagnoses were: aplastic/dysplastic kidneys (18%), obstructive uropathy (16%), and focal segmental glomerulosclerosis (12%). Preemptive transplant, i.e., transplantation without prior maintenance dialysis, was performed in 21% of the patients. Dialytic modalities pretransplant were peritoneal dialysis in 42% and hemodialysis in 25%. Bilateral nephrectomy was reported in 29%. Live-donor sources accounted for 42% of the transplants. Among cadaveric donors, 41% of the donors were under 11 years old. During the first post-transplant month, maintenance therapy was used similarly for live-donor and cadaver source transplants, with prednisone, cyclosporine, and azathioprine used in 93%, 83%, and 81%, respectively. Triple therapy with prednisone, cyclosporine, and azathioprine was used in 78%, 75%, and 75% of functioning cadaver source transplants at 6 months, 12 months, and 18 months as opposed to 60%, 63%, and 54% for live-donor procedures, with single-drug therapy being uncommon. Rehospitalization during months 1–5 occurred in 62% of the patients, with treatment of rejection and infection being the main causes. Additionally, 9% were hospitalized for hypertension. During months 6–12 and 12–17, 30% and 28% of the patients with functioning grafts were rehospitalized. Times to first rejection differed significantly for cadaver and live-donor transplants. The median time to the first rejection was 36 days for cadaver transplants and 156 days for live-donor transplants. Overall, 57% of treated rejections were completely reversible although the complete reversal rate decreased to 37% for four or more rejections. One hundred and fifty-two graft failures had occurred at the time of writing, with a 1-year graft survival estimate of 0.88 for live-donor and 0.71 for cadaver source transplants. In addition to donor source, recipient age is a significant prognostic factor for graft survival. Among cadaver donors, decreasing donor age is associated with a decreasing probability of graft survival. Thirty-five deaths have occurred; 16 attributed to infection and 19 to other causes. The current 1-year survival estimate is 0.94. There have been 9 malignancies.A list of all participating centers and the names of the investigators is printed on pages 552–553  相似文献   
3.
Plasmid DNA vectors have been constructed with minigenes encoding a single cytotoxic T lymphocyte (CTL) epitope from either the M2 protein of respiratory syncytial virus (RSV) or from the nucleoprotein of measles virus (MV) with or without a signal sequence (also called secretory or leader sequence). Following intradermal immunization, plasmids in which the CTL epitopes were expressed in-frame with the signal sequence were more effective at inducing peptide- and virus- specific CTL responses than plasmids expressing CTL epitopes without the signal sequence. This immunization resulted in protection against MV-induced encephalitis and a significant reduction in viral load following RSV challenge. The reduction of viral load following RSV challenge was abrogated by prior injection with anti-IFN-gamma antibodies. These results highlight the ability of epitope-based DNA immunization to induce protective immune responses to well-defined epitopes and indicate the potential of this approach for the development of vaccines against infectious diseases.   相似文献   
4.
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165  相似文献   
5.
Rigby  WF; Ball  ED; Guyre  PM; Fanger  MW 《Blood》1985,65(4):858-861
Interferons (IFNs) have been shown to have significant effects on hematopoietic cell growth. Previous studies defining these effects have utilized mouse and human alpha-, beta-, and gamma-IFN isolated from supernatants of stimulated cells. Despite purification, the possible presence of other lymphokines and soluble factors remains a concern. In this study, the effects of gene-cloned alpha- and gamma-IFN on colony- forming units of granulocyte/macrophage (CFU-GM) progenitors cultured from the peripheral blood of normal volunteers were examined. In addition, blast cell colonies from one patient with acute myelogenous leukemia (AML) were studied. The growth of normal CFU-GM and AML blast cell colonies was inhibited in a dose-dependent manner by gamma- and alpha-IFN. gamma-IFN was ten to 100 times more potent than alpha-IFN in that this species of IFN reduced colony formation by greater than 50% at concentrations of less than 15 antiviral U/mL. The effects of gamma- IFN were neutralized by a monoclonal antibody specific for gamma-IFN. These in vitro studies indicate that human gamma-IFN may be an important modulator of myelopoiesis. Although these data indicate a possible efficacy of gamma-IFN in the treatment of AML, the in vitro results should be considered for their in vivo significance.  相似文献   
6.
During the control period of the Growth Failure in Children With Renal Diseases Study, investigators at 23 centers were able to observe and characterize growth and to make anthropometric and nutritional measurements in 82 children with mild to moderate renal insufficiency. As a multicenter, controlled clinical trial designed to study the relative efficacy of 1,25-dihydroxyvitamin D3 and dihydrotachysterol in the treatment of renal osteodystrophy, no prior vitamin D exposure and a creatinine clearance of 25 to 75 ml/min/1.73 m2 were criteria for entrance into the clinical trial. Ages ranged from 18 months to 11 years (mean 5.6 +/- 3.1 years), and distribution by age category was as follows: 38%, 1 to 3 years; 28%, 4 to 6 years; and 34%, 7 to 10 years. There was a 3:1 male/female ratio; 72% of the patients had congenital disease by the International Classification of Diseases (ninth revision). Mean creatinine clearance was 49.5 +/- 20 ml/min/1.73 m2. The C-terminal parathyroid hormone values (1121 +/- 1562 pg/ml) were well above 2 SD of the mean of a normal growing population of similar age. Parathyroid hormone values correlated with degree of renal insufficiency (r = -0.57) and with height by bone age but not with chronologic height or growth velocity. The bone age/height age ratio, a predictor of growth potential in normal children, was low for the entire series of patients (0.88 +/- 0.35) but failed to correlate with growth velocity and was negatively correlated with rising parathyroid hormone levels. Average values for height, weight, triceps skin fold, mid-arm muscle circumference, and body mass index were within 2 SD of the mean of the normal population, although measurements for the 1- to 3-year age group were significantly less than those of the older patients. Total energy intake averaged less than 86% of the recommended dietary allowances; total protein intake was more than 161% of the allowance. Nitrogen balance in 23 patients was positive and correlated most significantly with increasing energy intake (r = 0.6). Growth velocity, calculated from the interval gain during the month control period, averaged +0.3 SD, with the highest growth velocity z scores recorded for those with acquired disease. A growth velocity index, expressed as the slope of the regression between change in height SD and growth velocity z score, was used to describe the growth accomplished in the control period by age category.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Seventy-six children with idiopathic MPGN have been followed at this medical center since 1957 (mean 10.6 years of disease). Seventy-one of the children have been treated with a regimen of prednisone (mean 7.7 years of treatment). Monotherapy with alternate-day prednisone was used in 50 of the children. Other immunosuppressive and cytotoxic drugs have not been used since 1981. In the 71 treated patients, the cumulative renal survival (creatinine less than 3.0 mg/dl (265.5 mumol/L)) was 82% in the tenth year and 56% in the twentieth year after disease onset. Cumulative renal survival, calculated from the date of initiation of the prednisone regimen, was 75% in the tenth year and 59% in the twentieth year. As our experience with this disease has increased, long-term cumulative renal survival has improved.  相似文献   
10.
Twenty-three episodes of acute elevation of BP related to renal disease in 13 chronically hypertensive children 2 to 18 years of age were treated with a single oral dose of minoxidil. All except one patient were receiving a diuretic and all but one a beta-blocking agent at the time of minoxidil treatment. The goal of lowering BP to or below the 95th percentile for age within four hours of minoxidil administration was achieved in 14 of 23 treatment episodes. The goal was achieved in nine of 11 (82%) when the dose of minoxidil was greater than or equal to 0.2 mg/kg and in five of 12 (42%) when the dose was less than 0.2 mg/kg (P less than .05). In patients treated with greater than or equal to 0.2 mg/kg of minoxidil, mean systolic and diastolic BP decreased significantly from pretreatment values within one hour. In patients receiving less than 0.2 mg/kg, mean systolic BP was never significantly reduced and mean diastolic BP did not change significantly for two hours. Adverse effects were minimal. The results indicate that minoxidil in a dose of 0.2 mg/kg in combination with a diuretic and beta-blocking agent will lower BP to safe levels in most patients with severe hypertension related to renal disease within four hours with minimal side effects.  相似文献   
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