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41.
Overexploitation of Neotropical ecosystems for wild meat constitutes a threat to biodiversity and might seriously affect local people who depend on wild animals as a primary food resource. To assess this problem at the local level, social use of wild animals was evaluated in a Mayan community of the Yucatan Peninsula. Over 8 months, peasant-hunters carried out a total of 175 hunting trips, gathering 253 animals of 12 species (mammals, birds and reptiles). Most preys (95%) were taken in 4 months (January–April) during the dry season and the main target species were white-tailed deer and iguana (jointly representing 59% of preys). During an 11-week period, total per capita wild meat consumption (182 kg; n = 14 families) was three times greater in nuclear than in extended families. The observed wild fauna use is a reflection of traditional knowledge and represents an important subsistence strategy for the local people.  相似文献   
42.
Myotonic dystrophy 1 (DM1) is an autosomal, dominant inherited, neuromuscular disorder. The DM1 mutation consists in the expansion of an unstable CTG-repeat in the 3'-untranslated region of a gene encoding DMPK (myotonic dystrophy protein kinase). Clinical expression of DM1 is variable, presenting a progressive muscular dystrophy that affects distal muscles more than proximal and is associated with the inability to relax muscles appropriately (myotonia), cataracts, cardiac arrhythmia, testicular atrophy and insulin resistance. DMPK is a Ser/Thr protein kinase homologous to the p21-activated kinases MRCK and ROCK/rho-kinase/ROK. The most abundant isoform of DMPK is an 80 kDa protein mainly expressed in smooth, skeletal and cardiac muscles. Decreased DMPK protein levels may contribute to the pathology of DM1, as revealed by gene target studies. Here we review current understanding of the structural, functional and pathophysiological characteristics of DMPK.  相似文献   
43.
Five specimens (four females and one male) of the Gorgona guitarfish, Pseudobatos prahli, were sighted during two dives carried out off the western Gulf of Tehuantepec. This document describes the reproductive condition of three adult females captured, two of which had uterine eggs, whereas one had embryos. The sighting and capture of specimens occurred during two Tehuano wind events; the authors, therefore, believe that variations in temperature and dissolved oxygen could have affected P. prahli, leading it to carry out temporal migrations towards coastal shallow waters.  相似文献   
44.
 Two tree shades (TS1 and TS2) and an artificial shade structure (AS) were evaluated using black globe temperatures (BGTs) to assess their effectiveness in reducing heat load. The artificial structure consisted of a black woven polypropylene cloth providing 80% shade, mounted on 2.5-m-high eucalyptus posts. The work was carried out at Rafaela Experimental Station, Argentina, during the summer (January and February) 1994. BGTs and floor temperatures were measured in concrete floor holding pens with and without artifical shade. The results showed no difference between TS1, TS2 and AS, their average BGTs being 30.2 (SD 0.58), 29.0 (SD 0.70) and 30.2 (SD 0.74)°C, respectively. BGTs under all three shades were significantly lower (P<0.01) than the average BGT recorded outside: 35.5 (SD 1.12)°C. Average BGTs in holding pens were 32.4 (SD 1.38) and 39.9 (SD 1.91)°C for shaded and non-shaded areas (P<0.01). The corresponding average floor temperatures were 27.8 (SD 0.68)°C and 47.7 (SD 2.13)°C (P<0.01). To assess the effects of shade on animal well-being, afternoon rectal temperatures (RT) and respiratory rate (respirations per minute, RR) of lactating cows were recorded twice a week. Rectal temperatures were significantly higher for non-shaded cows (P<0.01), mean RT being 40.1 (SD 0.65)°C vs 39.3 (SD 0.42)°C for the shaded animals. Corresponding RRs were 78.9 (SD 18.0) and 60.7 (SD 10.6) (P<0.05). It was concluded that: (1) tree and artificial shades produced similar effects, (2) shading the holding pen with an 80% shading cloth was effective in reducing heat load and floor temperatures, and (3) access to shade in our pasture-based system improved animal well-being. Received: 9 September 1996 / Revised: 10 March 1997 / Accepted: 2 July 1997  相似文献   
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46.

Introduction

Clinical and preclinical studies have shown that supplementation with ω-3 polyunsaturated fatty acids (ω-3 PUFAs) reduce joint destruction and inflammation present in rheumatoid arthritis (RA). However, the effects of individual ω-3 PUFAs on chronic arthritic pain have not been evaluated to date. Thus, our aim in this study was to examine whether purified docosahexaenoic acid (DHA, an ω-3 PUFA) reduces spontaneous pain-related behavior and knee edema and improves functional outcomes in a mouse model of knee arthritis.

Methods

Unilateral arthritis was induced by multiple injections of Complete Freund’s Adjuvant (CFA) into the right knee joints of male ICR adult mice. Mice that received CFA injections were then chronically treated from day 15 until day 25 post–initial CFA injection with oral DHA (10, 30 and 100 mg/kg daily) or intraarticular DHA (25 and 50 μg/joint twice weekly). Spontaneous flinching of the injected extremity (considered as spontaneous pain-related behavior), vertical rearing and horizontal exploratory activity (considered as functional outcomes) and knee edema were assessed. To determine whether an endogenous opioid mechanism was involved in the therapeutic effect of DHA, naloxone (NLX, an opioid receptor antagonist, 3 mg/kg subcutaneously) was administered in arthritic mice chronically treated with DHA (30 mg/kg by mouth) at day 25 post–CFA injection.

Results

The intraarticular CFA injections resulted in increasing spontaneous flinching and knee edema of the ipsilateral extremity as well as worsening functional outcomes as time progressed. Chronic administration of DHA, given either orally or intraarticularly, significantly improved horizontal exploratory activity and reduced flinching behavior and knee edema in a dose-dependent manner. Administration of NLX did not reverse the antinociceptive effect of DHA.

Conclusions

To the best of our knowledge, this report is the first to demonstrate DHA’s antinociceptive and anti-inflammatory effects as individual ω-3 PUFAs following sustained systemic and intraarticular administration in a mouse model of CFA-induced knee arthritis. The results suggest that DHA treatment may offer a new therapeutic approach to alleviate inflammation as well as a beneficial effect on pain-related functional disabilities in RA patients.  相似文献   
47.
48.

Background  

Genetic recombination maps provide important frameworks for comparative genomics, identifying gene functions, assembling genome sequences and for breeding. The molecular recombination map currently available for the model eudicot Antirrhinum majus is the result of a cross with Antirrhinum molle, limiting its usefulness within A. majus.  相似文献   
49.
High purity water for endocrine disruptors (EDs) analysis in experimental tests is an indispensable requirement for the preparation of reagents and solutions employed in biological laboratories. Commercial ultrapure water may contain traces of organic compounds, which can interfere with in vitro bioassays carried out to detect the potential estrogen-like activity of pure compounds and complex mixtures. This paper shows that solid-phase extracts of different types of ultrapure water (UPW) purchased or produced in situ for laboratory analysis (mQ-UPW) may contain organic molecules able to antagonize the binding of E2 to the human estrogen receptor α in the yeast estrogen screen (YES) assay. GC/MS analysis detected the presence of bis(2-ethylhexyl) phthalate (DEHP) (0.033 ppm ± 0.006) in mQ-UPW extracts. The dose–response curve of DEHP in the YES assay showed a relevant antagonist effect of this phthalate. Agreement between content of DEHP chemically detected in UPW extract and the magnitude of biological effects induced was pointed out. It would be appropriate that chemical analyses were complemented by biological tests to establish concentration limits for chemical contaminants in UPW that do not induce biological effects detectable in vitro. The yeast assay used in this study has previously proved to be a sensitive tool in assessing the presence of agonistic/antagonistic chemicals at the ng/l level in complex mixtures and may be successfully used to identify trace amounts of estrogenic/antiestrogenic chemicals, which can represent critical issues influencing the experimental results in environmental testing laboratories.  相似文献   
50.
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