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1.
We investigated Seneca Valley virus (SVV) contamination in pig feed and feed ingredients. Twenty‐seven samples were collected from two Brazilian feed mills and subjected to conventional RT‐nested‐PCR and qRT‐PCR assays. Seven samples were SVV‐positive with viral loads of 3.94–4.33 log10 genomic copies/g of feed. The study reveals SVV feed and feed ingredient contamination under natural conditions in Brazil.  相似文献   
2.
目的 比较不同膳食结构对去卵巢大鼠(OVX)骨量和骨结构的影响。方法 30只去卵巢大鼠随机分为3组,分别以基础、高脂和黄豆饲料喂养3个月。每周称体重一次,结算各组大鼠每天的摄食量。3个月后,采血测血清血脂水平、血钙、血磷和雌二醇;双能X线骨密度仪测定实验前、后大鼠全身、脊柱和股骨骨密度;取一侧股骨制备脱钙骨切片,进行骨形态学观察和骨计量学测定。结果 1、各组大鼠每天食物摄入量、血钙和血磷无统计学差异。2、黄豆饲料组大鼠体重最小(P<0.05);血清E2水平最高(P<0.05);全身、股骨和脊柱BMD均最高(P<0.05);骨小梁数量最多、骨小梁面积和厚度均最大(P<0.05)。而高脂饲料组大鼠体重最大(P<0.05);TG和LDL水平最高,HDL最低 (P<0.05);全身、股骨和脊柱BMD均最低(P<0.05),高脂饲料与基础饲料相比,骨小梁数量无差异,但骨小梁面积和厚度较大(P<0.05)。结论 从绝经后骨质疏松预防角度来说,富含黄豆的饮食较高脂饮食是一种较好的膳食结构;后者可能加速了女性的骨丢失。  相似文献   
3.
Economically relevant pathogens, such as African swine fever virus (ASFV), have been shown to survive when experimentally inoculated in some feed ingredients under the environmental conditions in transoceanic transport models. However, these models did not characterize the likelihood of virus survival under various time and temperature processes that feed ingredients undergo before they are added to swine diets. Here, we developed a quantitative risk assessment model to estimate the probability that one or more corn or soybean meal ocean vessels (25,000 tonnes) contaminated with ASFV would be imported into the United States annually. This final probability estimate was conditionally based on five likelihoods: the probability of initial ASFV contamination (p0), ASFV inactivation during processing (p1) and transport (p2), recontamination (pR), and ASFV inactivation while awaiting customs clearance at United States entry (p3). The probability of ASFV inactivation was modelled using corn and soybean (extruded or solvent extracted) processing conditions (times and temperatures), D-values (time to reduce 90% or 1-log) estimated from studies of ASFV thermal inactivation in pork serum (p1), and survival in feed ingredients during transoceanic transport (p2 and p3). ‘What-if’ scenarios using deterministic values for p0 and pR (1%, 10%, 25%, 50%, 75%, and 100%) were used to explore their impact on risk. The model estimated complete inactivation of ASFV after extrusion or solvent extraction processes regardless of the initial ASFV contamination probability assumed. The value of recontamination (ranging from 1% to 75%) was highly influential on the risk of one ASFV-contaminated soybean meal vessel entering the United States. Median risk estimates ranged from 0.064% [0.006%–0.60%; 95% probability interval (PI)], assuming a pR of 1.0%, up to 4.67% (0.45%–36.50% 95% PI) assuming a pR of 75.0%. This means that at least one vessel with ASFV-contaminated soybean meal would be imported once every 1563–21 years, respectively. When all raw corn was assumed to be contaminated (p0 = 100%), and no recontamination was assumed to occur (pR = 0%), the median probability of one vessel with ASFV-contaminated corn entering the United States was 2.02% (0.28%–9.43% 95% PI) or once every 50 years. Values of recontamination between 1% and 75% did not substantially change the risk of corn. Days of transport, virus survival during transport (D-value), and number of vessels shipped were the parameters most influential for increased likelihood of a vessel with ASFV-contaminated soybean meal or corn entering the United States. The model helped to identify knowledge gaps that are most influential on output values and serves as a framework that could be updated and parameterized as new scientific information becomes available. We propose that the quantitative risk assessment model developed in this study can be used as a framework for estimating the risk of ASFV entry into the United States and other ASFV-free countries through other types of imported feed ingredients that may potentially become contaminated. Ultimately, this model can be used to develop risk mitigation strategies and critical control points for inactivating ASFV during feed ingredient processing, storage, and transport, and contribute to the design and implementation of biosecurity measures to prevent the introduction of ASFV into the United States and other ASFV-free countries.  相似文献   
4.
The effects of Alcalase and Trypsin hydrolysis on the allergenic protein and its solubility of soybean meal (SBM) were investigated by SDS-PAGE and ELISA. After 10 min of hydrolysis with Alcalase, the solubility of the protein was 87.19%, the α′, α and β-subunits of β-conglycinin disappeared and the acidic and basic subunits of glycinin decreased obviously by SDS-PAGE pattern. However, with Trypsin for 10 min, the solubility of the protein was 72.74%. The contents of α′, α subunits of β-conglycinin decreased slightly in SDS-PAGE, and the acidic and basic subunits of glycinin were almost not affected. For the insoluble hydrolysates prepared by Alcalase, the α′, α subunits of β-conglycinin and acidic subunit of glycinin decreased significantly, that by trypsin did not. The content of immune-reactive β-conglycinin obtained by ELISA was consistent with them. These results confirmed that the allergenic proteins of SBM were more sensitive to Alcalase than to Trypsin.  相似文献   
5.
We investigated the effects of avocado/soybean unsaponifiables (ASU) on the healing response of cutaneous wound defect in rats. Sixty male rats were randomly divided into three groups including control, vehicle and treatment (n = 20 in each group). A 2 × 2 cm2 wound defect was made on the dorsum. The control, vehicle and treatment groups were treated daily with topical application of saline, cream and cream/ASU for 10 days, respectively. The wounds were monitored daily. The animals were euthanised at 10, 20 and 30 days post injury (D). The dry matter, hydroxyproline, collagen, n‐acetyl glucosamine (NAGLA) and n‐acetyl galactosamine (NAGAA) contents of the skin samples were measured and the histopathological and biomechanical characteristics of the samples were investigated. Statistics of P < 0·05 was considered significant. Treatment significantly increased tissue glycosaminoglycans and collagen contents at various stages of wound healing compared to controls. Treatment modulated inflammation, improved fibroplasia and produced high amounts of scar tissue at short term. At long term, treatment reduced the scar tissue size and increased the quality and rate of wound contraction and reepithelisation compared to controls. The treated lesions were more cosmetically pleasing and had significantly higher biomechanical characteristics than controls. ASU was effective in rat wound healing.  相似文献   
6.
目的:观察大豆异黄酮对骨质疏松大鼠种植体周围骨以及骨结合强度的影响。方法:选用4月龄雌性SD大鼠40只,用随机区组的方法将其分为假手术组(SHAM,10只)、卵巢切除组(OVX,10只)、卵巢切除+高剂量大豆异黄酮组(OVX+SIH,10只)和卵巢切除+低剂量大豆异黄酮组(OVX+SIL,10只)共4组。术后8周所有实验动物双侧胫骨干骺端分别植入钛螺纹钉1颗,2个药物干预组使用不同剂量SI药物干预12周。所有实验动物取包含螺纹钉的骨组织块进行生物力学、组织形态定量学检查。结果:与OVX组相比,低剂量和高剂量SI均能有效增加种植体的骨结合(组织形态定量学检测),并且增加了种植体的最大脱出力,其中高剂量SI组的种植体稳定性与对照组无显著差别(生物力学检测)。结论:本研究结果说明大豆异黄酮有剂量依赖性地改善骨质疏松大鼠钛螺纹钉的骨结合强度的可能性,增强疏松状态下种植体的稳定性。  相似文献   
7.
大豆蛋白对肾脏疾病的影响   总被引:1,自引:0,他引:1  
相锋  赵玉敏  廖晓艳  李亚洁 《护理研究》2005,19(16):1415-1417
从大豆蛋白的生物化学特性、动物实验研究、临床研究方面,综述了大豆蛋白对肾脏疾病的影响,简述了大豆蛋白对肾脏保护作用的机制.  相似文献   
8.
Background: Covering peritoneal surfaces with soybean oil may decrease peritoneal adhesions by preventing peritoneal trauma. Method(s): Forty female albino Wistar rats were divided into four equal groups. In Group 1, soybean oil only (0.1 ml) was injected into the peritoneal cavity. In Group 2, an untreated adhesion model was generated. In Group 3, an adhesion model was generated, followed by covering the area with soybean oil (0.1 ml). In Group 4, the area was first covered with soybean oil (0.1 ml) followed by generation of an adhesion model. All rats were sacrificed on postoperative day 10, and adhesions were scored. Results: The mean macroscopic adhesion scores in Groups 1, 2, 3, and 4 were 0.0 ± 0.0, 2.90 ± 0.21, 1.90 ± 0.94, and 0.50 ± 0.71, respectively. The Group 4 score differed significantly from that of Group 2 (p <. 001), but was not different from that of Group 1 or 3 (p >. 05). Discussion: Soybean oil can effectively decrease adhesion formation if applied before peritoneal trauma.  相似文献   
9.
Chronic consumption of processed food causes structural changes in membrane phospholipids, affecting brain neurotransmission. Here we evaluated noxious influences of dietary fats over two generations of rats on amphetamine (AMPH)-conditioned place preference (CPP). Female rats received soybean oil (SO, rich in n-6 fatty acids (FA)), fish oil (FO, rich in n-3 FA) and hydrogenated vegetable fat (HVF, rich in trans fatty acids (TFA)) for two successive generations. Male pups from the 2nd generation were maintained on the same supplementation until 41 days of age, when they were conditioned with AMPH in CPP. While the FO group showed higher incorporation of n-3 polyunsaturated-FA (PUFA) in cortex/hippocampus, the HVF group showed TFA incorporation in these same brain areas. The SO and HVF groups showed AMPH-preference and anxiety-like symptoms during abstinence. Higher levels of protein carbonyl (PC) and lower levels of non-protein thiols (NPSH) were observed in cortex/hippocampus of the HVF group, indicating antioxidant defense system impairment. In contrast, the FO group showed no drug-preference and lower PC levels in cortex. Cortical PC was positively correlated with n-6/n-3 PUFA ratio, locomotion and anxiety-like behavior, and hippocampal PC was positively correlated with AMPH-preference, reinforcing connections between oxidative damage and AMPH-induced preference/abstinence behaviors. As brain incorporation of trans and n-6 PUFA modifies its physiological functions, it may facilitate drug addiction.  相似文献   
10.
High–oleic acid soybean oil (H-OSBO) is a trait-enhanced vegetable oil containing >70% oleic acid. Developed as an alternative for trans-FA (TFA)-containing vegetable oils, H-OSBO is predicted to replace large amounts of soybean oil in the US diet. However, there is little evidence concerning the effects of H-OSBO on coronary heart disease (CHD)6 risk factors and CHD risk. We examined and quantified the effects of substituting high-oleic acid (HO) oils for fats and oils rich in saturated FAs (SFAs), TFAs, or n–6 (ω-6) polyunsaturated FAs (PUFAs) on blood lipids in controlled clinical trials. Searches of online databases through June 2014 were used to select studies that defined subject characteristics; described control and intervention diets; substituted HO oils compositionally similar to H-OSBO (i.e., ≥70% oleic acid) for equivalent amounts of oils high in SFAs, TFAs, or n–6 PUFAs for ≥3 wk; and reported changes in blood lipids. Studies that replaced saturated fats or oils with HO oils showed significant reductions in total cholesterol (TC), LDL cholesterol, and apolipoprotein B (apoB) (P < 0.05; mean percentage of change: −8.0%, −10.9%, −7.9%, respectively), whereas most showed no changes in HDL cholesterol, triglycerides (TGs), the ratio of TC to HDL cholesterol (TC:HDL cholesterol), and apolipoprotein A-1 (apoA-1). Replacing TFA-containing oil sources with HO oils showed significant reductions in TC, LDL cholesterol, apoB, TGs, TC:HDL cholesterol and increased HDL cholesterol and apoA-1 (mean percentage of change: −5.7%, −9.2%, −7.3%, −11.7%, −12.1%, 5.6%, 3.7%, respectively; P < 0.05). In most studies that replaced oils high in n–6 PUFAs with equivalent amounts of HO oils, TC, LDL cholesterol, TGs, HDL cholesterol, apoA-1, and TC:HDL cholesterol did not change. These findings suggest that replacing fats and oils high in SFAs or TFAs with either H-OSBO or oils high in n–6 PUFAs would have favorable and comparable effects on plasma lipid risk factors and overall CHD risk.  相似文献   
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