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101.
102.
Background: Patients receiving long‐term parenteral nutrition (PN) are at increased risk of aluminium (Al) toxicity because of bypass of the gastrointestinal tract during PN infusion. Complications of Al toxicity include metabolic bone disease (MBD), Al‐associated encephalopathy in adults, and impaired neurological development in preterm infants. Unlike the United States, there are no regulations regarding Al content of large‐ and small‐volume parenterals in Canada. We, therefore, aimed to present our data on plasma Al concentration and Al intake from our cohort of pediatric patients receiving long‐term PN. Methods: Plasma Al concentration was retrospectively gathered from the patient charts of all 27 patients with intestinal failure (IF) receiving long‐term PN at The Hospital for Sick Children, Toronto, Canada, and compared with age‐ and sex‐matched controls recruited for comparison. In addition, Al concentration was measured in PN samples collected from 10 randomly selected patients with IF and used to determine their Al intake. Results: The plasma Al concentration of patients with IF receiving long‐term PN was significantly higher than that of control participants (1195 ± 710 vs 142 ± 63 nmol/L; P < .0001). In the subgroup of 10 patients for whom Al intake from their PN solution was determined, mean ± SD Al intake from PN was 15.4 ± 15 µg/kg, 3 times the Food and Drug Administration upper recommended intake level, and Al intake was significantly related to plasma Al concentration (P = .02, r2 = 0.52). Conclusion: Pediatric patients receiving long‐term PN for IF in Canada are at risk for Al toxicity.  相似文献   
103.
The food chain is one of the major sources of human exposure to non-essential trace elements (TEs) present in soils. Human exposure to contaminated food is a worldwide health concern and a food safety issue that threatens agricultural trade. To assess the quality of Brazilian food products with respect to non-essential TEs, we evaluated arsenic (As), cadmium (Cd), and lead (Pb) contents in five major crops grown in Brazil: rice, wheat, corn, soybeans, and potatoes. The samples were collected from field trials with a record of long-term use of phosphate fertilizers in the states of Mato Grosso and Minas Gerais, Brazil. The TE concentrations in soils were all bellow the maximum allowable concentrations for agricultural soils. The mean concentrations of As, Cd, and Pb (μg kg−1 dry weight) were as follows: below the detection limit <15, 29, and <40 for rice; 19, 23, and 64 for wheat; 47, 40, and 95 for corn; 65, 23, and 106 for soybeans; and 59, 22, and <40 for potatoes, respectively. Significant differences were found in the As and Cd contents of the different wheat cultivars. The levels of As, Cd, and Pb found in the studied crops are well below the values reported in the literature and are in accordance with the Codex Alimentarius and the European Union and Brazilian guidelines, indicating that the concentrations of these elements in the crops do not pose a risk to human health.  相似文献   
104.
The P, Na, K, Ca, Mg, Fe, Cu, Zn and Mn concentrations were determined in seventy-three samples of seaweeds belonging to different genera (classified as brown, red and green seaweeds), which were collected from three zones in the sub-Antarctic ecoregion of Magallanes (Chile). There were clear differences in the concentrations between the considered genera. Brown seaweed had the highest mean K (31.4 g/kg) and Ca (10.3 g/kg) concentrations compared with red (14.1 g/kg for K and 3.11 g/kg for Ca) and green (13.9 g/kg for K and 7.58 g/kg for Ca) seaweed, and green seaweed had the highest mean Mg (15.0 g/kg), Fe (1260 mg/kg) and Cu (7.46 mg/kg) concentrations. The consumption of a serving (8 g) from of the three groups of brown, red and green seaweed is a good source of Fe, Mg and Mn (>25% of the Dietary Recommended Intake). Significant differences were observed in the mean concentrations of all the minerals and trace elements, except for Fe, Cu and Mn, between the three collection zones. Factor and discriminant analysis were used to differentiate the type of seaweed and sampling zone. Besides which, good classifications were obtained according to the type of seaweed using discriminant analysis.  相似文献   
105.
Potatoes (Solanum tuberosum L.) from the high Tiber valley area (TVA; Tuscany, Italy), have been sampled and analyzed for selected mineral content (Na, Mg, K, Ca, and Mn, Fe, Cu and Zn) and vitamin C, the year 2012; some samples from 2011 and 2013 crops were also collected and analyzed. The varieties were Daytona (DAY), Kennebec (KEN), Sifra (SIF) and Volare (VOL). Control samples consisted of mixed commercial varieties from the local market, namely C1, C2 and C3. The low content of sodium, especially for KEN (46 ± 3 mg/kg FD (freeze dry), year 2012) and SIF (47 ± 3) (VOL (55 ± 3) and DAY (61 ± 3) have a little higher values) is worth of note and in agreement with the scarce concentration of Na in the soil (291 ± 12 mg/kg DM). Magnesium was abundant in KEN (1434 ± 75 mg/kg FD, year 2012) and VOL (1334 ± 70). The content of K for DAY and KEN (13,147 ± 900 and 13,185 ± 900 mg/kg FD) was higher than for VOL and SIF; whereas Ca was in the range 340 ± 16–490 ± 28 mg/kg FD. The contents of Cu and Zn were higher in KEN (8.1 ± 0.3 and 25 ± 1 mg/kg FD) when compared to the other varieties and controls. The content of vitamin C is high for KEN and SIF and decreased significantly upon cooking (50% for KEN).  相似文献   
106.
Many trace elements are considered essential [iron (Fe), zinc (Zn), copper (Cu)], whereas others may be harmful [lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As)], depending on their concentration and chemical form. In most cases, the diet is the main pathway by which they enter our organism. The presence of toxic trace elements in food has been known for a long time, and many of the food matrices that carry them have been identified. This has led to the appearance of legislation and recommendations concerning consumption. Given that the main route of exposure is oral, passage through the gastrointestinal tract plays a fundamental role in their entry into the organism, where they exert their toxic effect. Although the digestive system can be considered to be of crucial importance in their toxicity, in most cases we do not know the events that occur during the passage of these elements through the gastrointestinal tract and of ascertaining whether they may have some kind of toxic effect on it. The aim of this review is to summarize available information on this subject, concentrating on the toxic trace elements that are of greatest interest for organizations concerned with food safety and health: Pb, Cd, Hg and As.  相似文献   
107.
目的:建立电感耦合等离子体发射光谱(ICP-AES)同时测定碳酸锂原料药中6种杂质元素(钙、钠、钾、镁、铁和铝)的分析方法,并分析不同厂商碳酸锂原料药的杂质含量。方法:用硝酸溶解样品, ICP-AES法分析样品中6种杂质元素的含量。结果:6种元素标准曲线的相关系数均高于0.999,加标回收率为93%~99%,检出限为0.0003~0.1275μg·mL-1,RSD值均小于2%;利用本法对5个厂家使用的碳酸锂原料药进行测定,结果表明C厂的原料药中钙、钠、镁、铁和铝元素含量均高于其余4个厂家,其中钠超出了药典规定限度。结论:与《中国药典》中碳酸锂原料药杂质测定方法进行比对,本试验所建立的方法测定结果与药典方法一致,且方法专属性强、灵敏度高、操作简单,可以用于碳酸锂原料药中6种杂质元素的测定。  相似文献   
108.
AIM: Trace elements (TE) metabolism is altered in inflammatory bowel diseases. TE (zinc and copper) are constituents of antioxidant enzymes. Iron is involved in the pathogenesis of chronic inflammation. The aim was to evaluate zinc and copper status and the effects of iron manipulation in experimental colitis. METHODS: Twenty-four male Sprague-Dawley rats were divided into four groups: standard diet, iron-deprived diet, iron-supplemented diet, and sham-treated controls. Macroscopic damage was scored. DNA adducts were measured in the colon. Liver and colonic concentration of TE were measured. RESULTS: Macroscopic damage was reduced in iron-deprived groups and increased in iron-supplemented rats. Damage to the DNA was reduced in iron-deprived groups and increased in iron-supplemented groups. Liver and colonic iron concentrations were reduced in iron-deprived and increased in iron-supplemented rats. Liver zinc concentration was reduced after supplementation whereas colonic levels were similar in controls and treated rats. Liver copper concentration was reduced in all the colitic groups except in the iron-supplemented group whereas colonic concentration was increased in iron-deprived rats. CONCLUSION: Iron deprivation diminishes the severity of DNBS colitis while supplementation worsens colitis. Zinc and copper status are modified by iron manipulation.  相似文献   
109.
Summary The velocity field and the wall shear stress have been calculated numerically by the finite element method to the time-dependent Navier-Stokes equations for pulsatile flow in a model of an aneurysm. The results show a complex flow field with two eddies growing and disappearing during the cardiac cycle. Downstream at the outlet vessel high wall shear stress occurs, which may lead to a downstream-growing of the aneurysm.With the knowledge of a sufficiently accurate flow field, the calculation of several particle paths has been carried out. Starting points and starting time are varied. The paths demonstrate the time-dependent development, shift and disappearance of vortices during the pulsatile cycle and provide hints on zones of stasis. These are significant factors in thrombogenesis.Supported by the Fonds zur Förderung der wissenschaftlichen Forschung, project number P4671  相似文献   
110.
目的研究脾虚证实质、脾虚证与胃癌发生的关系。方法采用 IBAS2000型图象分析系统、501B 型扫描电镜附有9100/60型能量色散 X 分析仪,以及组织化学与放射免疫方法,检测脾虚证患者胃粘膜超微结构、肠化生亚型、DNA、cAMP、微量元素及其氧化物。结果脾虚色滞证患者中胃癌发生率、不完全性结肠型肠化生发生率和"背景病变"发生率均显著高于脾气虚证患者;胃粘膜 cAMP、Zn、Cu、ZnO 和 Cuo 含量,随着肠化生完全性至不完全性、小肠型至结肠型的顺序递减;而 DNA 含量则随以上顺序递增,P<0.05~0.001。胃粘膜不完全性结肠型肠化生组织内 DNA、cAMP、Zn、Cu、ZnO 和 CuO 含量则与胃癌组织同元显著性差异。结论脾虚气滞证胃病有癌变倾向;不完全性结肠型肠化生与胃癌的发生有密切关系。@何雪芬$目的!研究脾虚证实质、脾虚证与胃癌发生的关系。方法采用 IBAS2000型图象分析系统、501B 型扫描电镜附有9100/60型能量色散 X 分析仪,以及组织化学与放射免疫方法,检测脾虚证患者胃粘膜超微结构、肠化生亚型、DNA、cAMP、微量元素及其氧化物。结果脾虚色滞证患者中胃癌发生率、不完全性结肠型肠化生发生率和"背景病变"发生率均显著高于脾气虚证患者;胃粘膜 cAMP、Zn、Cu、ZnO 和 Cuo 含量,随着肠化生完全性至不完全性、小肠型至结肠型的顺序递减;而 DNA 含量则随以上顺序递增,P<0.05~0.001。胃粘膜不完全性结肠型肠化生组织内 DNA、cAMP、Zn、Cu、ZnO 和 CuO 含量则与胃癌组织同元显著性差异。结论脾虚气滞证胃病有癌变倾向;不完全性结肠型肠化生与胃癌的发生有密切关系。@尹玉芬$目的!研究脾虚证实质、脾虚证与胃癌发生的关系。方法采用 IBAS2000型图象分析系统、501B 型扫描电镜附有9100/60型能量色散 X 分析仪,以及组织化学与放射免疫方法,检测脾虚证患者胃粘膜超微结构、肠化生亚型、DNA、cAMP、微量元素及其氧化物。结果脾虚色滞证患者中胃癌发生率、不完全性结肠型肠化生发生率和"背景病变"发生率均显著高于脾气虚证患者;胃粘膜 cAMP、Zn、Cu、ZnO 和 Cuo 含量,随着肠化生完全性至不完全性、小肠型至结肠型的顺序递减;而 DNA 含量则随以上顺序递增,P<0.05~0.001。胃粘膜不完全性结肠型肠化生组织内 DNA、cAMP、Zn、Cu、ZnO 和 CuO 含量则与胃癌组织同元显著性差异。结论脾虚气滞证胃病有癌变倾向;不完全性结肠型肠化生与胃癌的发生有密切关系。  相似文献   
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