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41.
Summary Addition of vitamins and minerals to foods must be done without health risk to any consumer group. International expert groups
have aimed at establishing tolerable upper intake levels (ULs) for vitamins and minerals although lack of solid data on their
safety is a major obstacle to this work. In this paper, we summarize the existing ULs and suggest the use of guidance levels
(GLs) set by others and temporary guidance levels (TGLs) proposed here, whenever no consensus UL has been established for
adults. We suggest the use of body surface area ratios to establish similar levels for younger age groups. The levels are
applied in a model for calculation of safe fortification levels for all ages.We have estimated the upper 95th percentile intake of vitamins and minerals from food in various Danish age and gender groups and suggest that a daily multivitaminmineral
pill is included in the calculation of total dietary intake levels of all vitamins and minerals. By subtracting this dietary
intake level from the UL, GL or TGL, we calculate the amount that can be safely used for fortification. Since safety must
be assured for all age groups, the smallest difference relative to energy intake calculated for any age group is proposed
as the maximal allowance (MA) for fortification with each nutrient. We suggest that the MA should be expressed in weight units
per energy unit in order to distribute it equally between potentially fortifiable food groups according to their usual contribution
to total energy intakes. 相似文献
42.
The therapeutic efficacy of a crude water extract of Khaya grandifoliola has been established in mice. This study was designed to assess the effect of the extract on the red blood cells and bone for 7 days, 3 weeks and a recovery period of 3 weeks. Daily administration of the extract showed no related adverse effects on the mortality rate, physical appearance or behaviour of the rats. A general pattern of significant (p < 0.5) increases in the red blood cell (RBC) count, PCV, haemoglobin and plasma iron content was shown by groups administered with extract after 7 and 21 days when compared with control rats. There was a general trend of reduction in the bone minerals determined (Ca, P, Mg and Cu) in the extract administered groups. Significant (p < 0.5) decreases were observed at the 500 mg/kg concentration. The bone potassium and iron content was significantly (p < 0.5) increased in rats administered with extract in a dose-dependent manner. There was an observed significant (p < 0.5) decrease in alkaline phosphatase (ALP) activity in the rats administered with the extract when compared with the control animals.During the recovery period, the haematological indices regressed to values which were still significantly (p < 0.5) higher than those of the control values.These results indicate that K. grandifoliola has a positive effect on erythropoeisis, but no significant effect on bone mineral contents at therapeutic doses.At extremely high doses and during prolonged administration, it may have an adverse effect on bone minerals. 相似文献
43.
44.
《Critical reviews in toxicology》2013,43(6):513-530
Industrial-grade talc deposits are complex mixtures of mineral particles and may vary substantially in composition across small geographical areas. Typical industrial-grade talc includes amphibole cleavage fragments, platy talc, serpentine minerals, talc in fibrous form, and a minor presence of transitional fibers. Industrial-grade talc was erroneously determined to be an asbestos-containing material due to an unintended consequence of Occupational Health and Safety Administration’s (OSHA’s) method for measuring airborne asbestos mandated in 1972. This error was repeated, most notably, by the National Institute for Occupational Safety and Health (NIOSH) in, 1980 for talc mined in northern New York State (NYS) by RT Vanderbilt Company (RTV). Subsequent exposure studies of northern NYS talc conducted through the, 1980s and one study published after, 2000 relied on the conclusion that talc was an asbestos-containing material to infer a causal relationship between talc and mesothelioma. The present review included (1) publications concerning talc’s cancer-causing potential issued by organizations concerned with occupational and public health; (2) talc exposure studies and animal and cellular studies of RTV talc; (3) mesothelioma rates in northern NYS; and (4) mesothelioma mortality among RTV mining employees. The review indicated that failure to correctly identify the mineral characteristics of talc resulted in misleading reports concerning the carcinogenic potential of talc. However, the collective data from animal and cellular studies, mesothelioma rates in northern NYS, exposure studies, and a mortality analysis of RTV mining employees do not support a causal relationship between RTV talc and mesothelioma. This conclusion is applicable to all mineral components in RTV talc and to other industrial-grade talcs and mineral aggregates with the same components. 相似文献
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47.
目的 比较矿物质水平差别显著的3种饮水对大鼠繁殖能力和子代发育的影响.方法 将45只雄性和90只雌性断乳SD大鼠按随机数字表法分为3组(雌雄比为2∶1),分别饮用A水[溶解性总固体(total dissolved solids, TDS)为1.2 mg/L]、B水(TDS:87.2 mg/L)以及经净水器(活性炭滤芯)处理自来水后得到的C水(TDS:291.0 mg/L),连续3代.逐代比较亲代繁殖指标和子代发育指标.结果 亲3代的繁殖指标3组间均未见统计学差异.A水组仔鼠出生后4 d存活率至F3代时明显低于其他2组.而C水组仔鼠出生后4 d存活率不仅在F1代时显著高于B水组(P<0.01),还在F3代时显著高于其他2组,该组在F1代时记忆能力也有高于其他2组的趋势.结论 多代连续饮用矿物质极低的饮水对大鼠繁殖能力影响不明显,但低矿水对子代早期发育水平可能有不利影响.对于大鼠出生后的早期生长阶段,饮用卫生学上安全且富含矿物质的饮水将对其发育更为有利. 相似文献
48.
49.
Survey of Vitamin and Mineral Supplementation after Gastric Bypass and Biliopancreatic Diversion for Morbid Obesity 总被引:5,自引:1,他引:4
Background: The authors investigated whether practice patterns of bariatric surgeons correlate with published data regarding
metabolic deficiencies after Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD). Methods: 109 surgeons completed
a questionnaire to determine use of supplements and frequency of lab tests. Results: Regarding supplements routinely prescribed
after RYGB, 96% of surgeons gave multivitamins, 63% gave iron, and 49% gave vitamin B12. After BPD, 96% of surgeons gave multivitamins, 67% gave iron, 42% gave vitamin B12, 97% gave calcium, 63% gave fat-soluble vitamins, and 21% gave protein supplements. Regarding laboratory tests obtained routinely
after RYGB, 95% of surgeons do complete blood counts, 56% do iron determinations, 66% do vitamin B12 determinations, 58% do folate determinations, 76% do electrolyte determinations, and 8% test for proteins. After BPD, 96%
of surgeons do complete blood counts, 80% do iron determinations, 67% do vitamin B12 determinations, 71% do folate determinations, 88% do electrolyte determinations, 84% do protein determinations, and 46% test
for fat-soluble vitamins. Regarding frequency of blood tests, after RYGB, 22% of surgeons obtain them after 3 months, 33%
after 6 months, and 41% after 12 months; 4% do not routinely obtain postoperative laboratory tests. After BPD, 46% of surgeons
obtain them after 3 months, 33% after 6 months, and 16% after 12 months; one does not obtain laboratory tests. Surgeons estimated
these deficiencies after RYGB: 16% iron, 12% vitamin B12, 14% anemia, 5% protein, and 3% calcium. They estimated these deficiencies after BPD: 26% iron, 11% vitamin B12, 21% anemia, 18% protein, 16% calcium, and 6% fat-soluble vitamins. The estimated incidence of deficiencies after RYGB was
considerably lower than the published incidence. Unnecessary tests were commonly performed (electrolytes after RYGB). Conclusion:
Despite wide variations in the performance of laboratory tests and the use of supplements, the practice patterns of most surgeons
protect patients from developing severe metabolic deficiencies after RYGB and BPD. 相似文献
50.
四种直翅目昆虫矿物质营养成分分析 总被引:6,自引:1,他引:5
在人和动物体内已查明的矿物质元素达 50多种 ,但在某一动物体内多数矿物质成分含量少 ,其总量一般不超过 4%~ 5% [1] 。在以往的研究报道中 ,矿物元素的测定值通常由畜、禽、乳、蛋和水产品中测出[2 ] 。近年昆虫作为一类新的动物营养源日益受到重视 ,学者们对蝠蛾、蚁类和稻蝗矿质营养成分 [3~ 5] ,及某些昆虫部分常量或微量元素进行了分析、评价与测定[6~ 8] 。然而直翅目昆虫种类多、数量大、分布广 ,迄今对矿物质营养成分的分析研究甚少 ,除上述稻蝗 (Oxya,蝗总科 Acridoidea)报道[4 ,5]外 ,很多蝗虫种尚待研究。研究选择四种具代… 相似文献