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1.
目的 建立一种超高效亲水作用色谱串联三重四极杆质谱法(UHILIC-MS/MS),同时测定复方三维右旋泛酸钙糖浆中维生素B1、维生素B2、维生素B6、烟酰胺和泛酸钙的含量。方法 采用超高效液相色谱仪,Waters ACQUITY BEHHILIC Amide色谱柱(2.1 mm×100 mm,1.7 μm),以90%乙腈(含0.5%甲酸)-10 mmol/L甲酸铵水(含0.5%甲酸)为流动相,进行梯度洗脱,流速0.30 ml/min;在电喷雾(ESI)正离子模式下,用多反应监测(MRM)模式进行含量测定。结果 在5 min内,样品中5种维生素分别在各自考察的浓度范围内呈良好的线性关系,相关系数(r)均大于0.998 4;整体加样回收率在93.27%~100.39%之间,RSD为1.41%~4.96%;10批样品中维生素B1、维生素B2、维生素B6、烟酰胺、泛酸钙的含量测定结果分别为32.40~38.91、7.002~8.462、9.677~11.17、33.64~39.58、3.276~3.771 mg/250 g。结论 本研究建立的UHILIC-MS/MS方法可快速实现对复方三维右旋泛酸钙糖浆中5种维生素类成分定性鉴定或定量检测,为复方三维右旋泛酸钙糖浆的开发利用和质量评价提供了可靠的技术检测方法。  相似文献   
2.
Mutations in the cystathionine beta‐synthase (CBS) gene are the cause of classical homocystinuria, the most common inborn error in sulfur metabolism. The c.797 G>A (p.R266K) mutation in CBS was originally described in several Norwegian pyridoxine responsive CBS deficient patients, and heterologous gene expression studies have shown that the protein has near wild‐type levels of enzyme activity. Here, we characterize a transgenic mouse lacking endogenous Cbs and expressing p.R266K human CBS protein from a zinc inducible metallothionein promoter (Tg‐R266K Cbs‐/‐). Unlike mice expressing other mutant CBS alleles, the Tg‐R266K transgene is unable to efficiently rescue neonatal lethality of Cbs‐/‐ on a C57BL/6J background. On a C3H/HeJ background, zinc‐induced Tg‐R266K Cbs‐/‐ mice express CBS mRNA, but have very low levels of CBS protein and enzyme activity, resulting in extreme elevations in serum total homocysteine (tHcy). Treatment with pyridoxine did not have any appreciable effect on tHcy, indicating this allele is not pyridoxine responsive in mice. However, treatment with the proteasome inhibitor bortezomib resulted in an 97% reduction in tHcy and a 2381% increase in liver CBS activity. These studies show that the p.R266K mutation causes increased proteasomal degradation in vivo, and that treatments that stabilize the protein can be used to reverse its effect.  相似文献   
3.
Hormonal contraceptives may produce side effects that deter women from their use as a method of family planning. In nutritionally vulnerable populations these effects may be more pronounced due to micronutrient deficiencies and health status. Previous studies have been unable to resolve whether micronutrient supplementation may reduce such side effects. Aim: In a longitudinal study, 1011 women obtaining oral contraception through the public health system in rural Cambodia were allocated to either intervention or control groups, receiving either daily Vitamin B6 supplement or care as usual (without placebo). Results: The intervention participants (n = 577) reported fewer side effects in three categories: nausea/no appetite, headache, and depression compared with control group participants (n = 434). Conclusion: Women taking Vitamin B6 supplement were less likely to report side effects in a nutritionally vulnerable population. Underlying nutrition status should be considered by clinicians and reproductive health policy makers in the context of providing contraceptive services. Further investigation into micronutrient supplementation, particularly with B6, in reproductive-aged women using hormonal contraception should be conducted in other settings to determine the potential for widespread adoption.  相似文献   
4.
5.
Excessive urinary oxalate excretion, termed hyperoxaluria, may arise from inherited or acquired diseases. The most severe forms are caused by increased endogenous production of oxalate related to one of several inborn errors of metabolism, termed primary hyperoxaluria. Recurrent kidney stones and progressive medullary nephrocalcinosis lead to the loss of kidney function, requiring dialysis or transplantation, accompanied by systemic oxalate deposition that is termed systemic oxalosis. For most primary hyperoxalurias, accurate diagnosis leads to the use of therapies that include pyridoxine supplementation, urinary crystallisation inhibitors, hydration with enteral fluids and, in the near future, probiotic supplementation or other innovative therapies. These therapies have varying degrees of success, and none represent a cure. Organ transplantation results in reduced patient and organ survival when compared with national statistics. Exciting new approaches under investigation include the restoration of defective enzymatic activity through the use of chemical chaperones and hepatocyte cell transplantation, or recombinant gene therapy for enzyme replacement. Such approaches give hope for a future therapeutic cure for primary hyperoxaluria that includes correction of the underlying genetic defect without exposure to the life-long dangers associated with organ transplantation.  相似文献   
6.
Characteristics of pyridoxine overdose neuropathy syndrome   总被引:4,自引:0,他引:4  
A newly recognised neurotoxic syndrome due to pyridoxine (B6) overdose is described. It is the largest series of B6 intoxication hitherto reported. A raised serum B6 level was present in 172 women of whom 60% had neurological symptoms, which disappeared when B6 was withdrawn and reappeared in 4 cases when B6 was restarted. The mean dose of B6 in the 103 women with neurological symptoms was 117 +/- 92 mgs, compared with 116.2 +/- 66 mgs in the control group. There was a significant difference (P less than 0.01) in the average duration of ingestion of B6 in the neurotoxic group of 2.9 +/- 1.9 years compared with 1.6 +/- 2.1 years in controls. The symptoms were paraesthesia, hyperaesthesia, bone pains, muscle weakness, numbness and fasciculation, most marked on the extremities and predominantly bilateral unless there was a history of previous trauma to the limb. These women were taking a lower dose of B6 than previously described (1,2), which may account for the complete recovery within 6 months of stopping B6.  相似文献   
7.
《Nutrition reviews》1986,44(1):24-26
Pyridoxine deficiency in perinatal and weanling rats leads to decreases in lung conversion of elastin lysyl to allysyl residues, with an increase in aldol condensation products.  相似文献   
8.
The role of protein and calorie deficiency in sickle cell disease remains poorly defined. While such features as growth retardation, impaired immune function, and delayed menarche do suggest a relationship between sickle cell disease and undernutrition, measurement of more direct nutritional parameters in these patients have yielded mixed results. Anthropometric measurements such as skinfold thickness are subnormal in many but not all reports. Serum protein levels are normal, but low values for serum lipids have been reported. Finally, one small study shows an improvement in both growth parameters and clinical course following caloric supplementation. A variety of micronutrient deficiencies have been suggested in sickle cell disease. Numerous case reports describing an exacerbation of the chronic anemia that was reversed by folic acid therapy led to routine folate supplementation. More recent studies have shown, however, that clinically significant folic acid deficiency occurs only in a small minority of sickle cell patients. Clearly, more work is necessary to define the cost/benefit ratio of routine folic acid supplementation. Pharmacological amounts of vitamin B6 and certain of its derivatives possess in vitro antisickling activities. Nevertheless, a small clinical trial failed to demonstrate any consistent hematologic effects of B6 supplementation. Several reports indicate that vitamin E levels are low in sickle erythrocytes. Since these abnormal red cells both generate excessive oxidation products and are more sensitive to oxidant stress, and because oxidants appear to play a role in ISC formation, vitamin E deficiency could well be linked to ISC formation and hemolysis. Small clinical trials, however, have again failed to produce a clear hematological response in sickle cell anemia. The role of zinc in sickle cell disease has received considerable attention. Though studies are generally small, most do support a relationship between sickle cell disease and zinc deficiency. Etiologic associations between zinc deficiency and such complications of sickle cell disease as poor ulcer healing, growth retardation, delays in sexual development, immune deficiencies, and high ISC counts have all been suggested. Most of these studies need further corroboration. Iron deficiency is now known to be a relatively common occurrence in sickle cell anemia, especially in children and pregnant women. The theoretical benefits of concomitant iron deficiency and sickle cell anemia remain to be proven in a controlled clinical trial.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
9.
考察了芳香族氨基酸和维生素对转酮醇酶缺失的枯草芽孢杆菌生长以及D-核糖生产的影响。实验结果表明:L-酪氨酸、L-色氨酸、L-苯丙氨酸、生物素、烟酸、吡哆醛的添加能改善菌体生长,提高D-核糖产量,特别是烟酸作用尤其明显。在单因素实验基础上,采用响应面分析方法对培养基中的维生素添加量进行了优化,确定最佳培养基组成。在此优化培养基中D-核糖质量浓度达到 (23.4±0.39) g/L,与预测结果一致,是不添加维生素时核糖产量的2.31倍,D-核糖对葡萄糖的得率达到0.353 mol/mol。  相似文献   
10.
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