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221.

Background

Tail biting is a common welfare problem in pig production and in addition to being a sign of underlying welfare problems, tail biting reduces welfare in itself. The aim of this study was to evaluate the effects of tail biting on different pre and post mortem indicators of stress in slaughter pigs and on carcass and meat characteristics. A total of 12 tail bitten (TB) and 13 control (C) pigs from a farm with a long-term tail biting problem were selected for salivary cortisol analyses before and after transport to the slaughterhouse. After stunning, samples were taken for the analysis of serum cortisol, blood lactate, intestinal heat shock protein 70 (HSP70), and meat quality characteristics. In addition, body temperature immediately after and muscle temperature 35 min after stunning were measured, as well as lean meat percentage and carcass weight.

Results

TB pigs showed a lower cortisol response to the transport-induced stress than C pigs and also had a lower serum cortisol concentration after stunning. HSP70 content in the small intestine was higher in the TB pigs than in C pigs. TB pigs had a considerably lower carcass weight therefore produced a lower total amount of lean meat per carcass than C pigs.

Conclusions

This study suggests that prolonged or repeated stress in the form of tail biting causes a blunted stress response, possibly a sign of hypocortisolism. In addition, it underlines the importance of reducing tail biting, both from an animal welfare and an economic point-of-view.
  相似文献   
222.

Background

Television viewing time (TV time) is associated with increased weight and obesity, but it is unclear whether this relation is causal.

Methods and Results

We evaluated changes in TV time, waist circumference (waist) and body mass index (BMI) in participants of the population-based Cardiovascular Risk in Young Finns study (761 women, 626 men aged 33–50 years in 2011). Waist and BMI were measured, and TV time was self-reported in 2001, 2007, and 2011. Changes in waist and BMI between 2001 and 2011 were studied a) for the whole group, b) in groups with constantly low (≤1 h/d), moderate (1–3 h/d), or high (≥3 h/d) TV time, and c) in groups with ≥1 hour in-/decrease in daily TV time between 2001 and 2011. BMIs in 1986 were also evaluated. We explored the causal relationship of TV time with waist and BMI by classical temporality criterion and recently introduced causal-discovery algorithms (pairwise causality measures). Both methods supported the hypothesis that TV time is causative to weight gain, and no evidence was found for reverse or bidirectional causality. Constantly low TV time was associated with less pronounced increase in waist and BMI, and waist and BMI increase was lower with decreased TV time (P<0.05). The increase in waist and BMI was at least 2-fold in the high TV time group compared to the low TV time group (P<0.05). Adjustment for age, sex, BMI/waist in 2001, physical activity, energy intake, or smoking did not change the results.

Conclusions

In young and middle-aged adults, constantly high TV time is temporally antecedent to BMI and waist increase.  相似文献   
223.
Isoflavones form a group of plant compounds that occur mainly in legumes, soy being the most important source in human diet. The high levels of isoflavones in the diet have been associated with a lowered risk for hormone-dependent diseases, including breast and prostate cancers, osteoporosis and cardiovascular disease. The metabolism of isoflavones in humans has been studied to a certain extent, but detailed studies are lacking. This paper reviews the current knowledge on metabolism of isoflavones and presents some preliminary results of a comprehensive soy feeding study, in which the phase I metabolites of soy isoflavones, daidzein, genistein and glycitein, were identified by GC-MS. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
224.
The possible effect of chemical and physical factors during pregnancy on the occurrence of cardiovascular malformations in the offspring was studied in 573 cases and 1,055 controls. The cases represented all verified cardiovascular malformations in Finland during 1982-1984. The controls were randomly selected from all babies born during the same period. Case and control mothers were interviewed by midwives approximately 3 months after delivery using a structured questionnaire. Maternal alcohol consumption during the first trimester of pregnancy was more common among the mothers of case infants (45.9%) than those of controls (39.6%). Exposure to organic solvents at work was slightly more prevalent among the ventricular septal defect group (12.1%) than the control mothers (7.8%). However, neither association was significant when adjusted for maternal age in logistic regression analysis. Moreover, one or both of these associations may be chance effects resulting from multiple comparisons. The risk of cardiovascular malformations was not associated with maternal smoking, or coffee, tea, or cola consumption, and was equal in urban and rural areas. Maternal exposures to anesthetic gases, pesticides, wood preservatives, microwave ovens, and video display terminals at work or home were not associated with the risk of cardiovascular malformations. It is concluded that some common environmental exposures during early pregnancy to physical and chemical factors should not necessarily be considered hazardous for the developing fetal heart. The causes of the majority of cardiovascular malformations remain unknown.  相似文献   
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226.
The eyelids of goats in Kenya contained several, conspicuous white cysts which were up to 1.5 mm in size. By histological and electron microscopical studies it was confirmed that these cysts belong to the genus Besnoitia.  相似文献   
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229.
Metal concentrations in the gill, muscle and liver tissues of Labeo rosae from two impoundments, Loskop and Flag Boshielo dams on the Olifants River, were evaluated in 2011 to detect patterns in metal associations between tissues and impoundments. Elevated concentrations of Ba, Zn, B, Al, Si and Fe, relative to a pristine site in the catchment, were found in the muscle, liver and gill tissues at both impoundments. Molybdenum concentrations were exceptionally high in all tissues at Loskop Dam and in liver at Flag Boshielo Dam. No definite pattern in the ratio metal concentrations within, or between, fish tissues was identified. The expected trend, liver > gills > muscle, was found at both impoundments, but was less prominent at Loskop Dam. Metal concentrations in muscle of Loskop Dam fish were significantly higher than in those at Flag Boshielo Dam. The inverse was true for liver. The long-term impact of elevated metal concentrations on fish health at both impoundments raises concern.  相似文献   
230.
Summary The effect of transfer factor (TF) immunotherapy on recurrent papillary bladder tumours (grade 0 papilloma and grade 1 and grade 2 carcinoma) has been studied. In a double blind study 27 patients received either TF derived from nonimmune normal donors or physiological saline. The follow-up period was 1 year. There was no difference between the two treatment groups with regard to clinical responses. Circulating immune complexes and responses to various skin test antigens were also analysed. Responses to skin test antigens and the level of circulating immune complexes did not correlate with clinical status, and TF had no effect on these parameters.  相似文献   
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