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31.
Ajdžanović V Spasojević I Sošić-Jurjević B Filipović B Trifunović S Sekulić M Milošević V 《The Journal of membrane biology》2011,239(3):131-135
A decrease of erythrocyte membrane fluidity can contribute to the pathophysiology of hypertension. Soy products, which are
used as alternative therapeutics in some cardiovascular conditions, contain various isoflavones (genistein, daidzein, and
their glucosides, genistin and daidzin), which can incorporate cellular membrane and change its fluidity. The aim of this
study was to examine the effects of soy extract (which generally corresponds to the soy products of isoflavone composition)
on erythrocyte membrane fluidity at graded depths. We used electron paramagnetic resonance spectroscopy and fatty acid spin
probes (5-DS and 12-DS), the spectra of which are dependent on membrane fluidity. After being treated with soy extract, erythrocytes
showed a significant (P = 0.016) decrease of membrane fluidity near the hydrophilic surface, while there were no significant changes of fluidity
in deeper hydrophobic membrane regions. These results suggest that soy products containing high levels of genistein and isoflavone
glucosides may not be suitable for use in hypertension because they decrease erythrocyte membrane fluidity. 相似文献
32.
Bacillus anthracis, the causative agent of anthrax, is known as one of the most genetically monomorphic species. Canonical single-nucleotide polymorphism (SNP) typing and whole-genome sequencing were used to investigate the molecular diversity of eleven B. anthracis strains isolated from cattle in Denmark between 1935 and 1988. Danish strains were assigned into five canSNP groups or lineages, i.e. A.Br.001/002 (n = 4), A.Br.Ames (n = 2), A.Br.008/011 (n = 2), A.Br.005/006 (n = 2) and A.Br.Aust94 (n = 1). The match with the A.Br.Ames lineage is of particular interest as the occurrence of such lineage in Europe is demonstrated for the first time, filling an historical gap within the phylogeography of the lineage. Comparative genome analyses of these strains with 41 isolates from other parts of the world revealed that the two Danish A.Br.008/011 strains were related to the heroin-associated strains responsible for outbreaks of injection anthrax in drug users in Europe. Eight novel diagnostic SNPs that specifically discriminate the different sub-groups of Danish strains were identified and developed into PCR-based genotyping assays. 相似文献
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35.
Kristek J Marjanović K Dmitrović B Krajinović Z Sakić K 《Collegium antropologicum》2005,29(2):775-777
Authors report about a patient with recurrent ductal invasive breast carcinoma and trichinosis. The patient underwent mastectomy of the left breast with evacuation of the axilla because of the cancer. Radiation therapy was received. An infestation with Trichinella spiralis was diagnosed two years after The patient was treated with mebendazole. A local recurrence of the tumor was found on the chest wall six years after the surgery. Tumor excision was performed. Histological analysis pointed at a ductal invasive carcinoma with numerous parasites of Trichinella spiralis present within both the muscle and the tumor tissue. The finding of parasites in the tumor tissue witnesses in favor of infestation, and the parasite morphology preserved in the tumor shows at the protective effects of the cysts, i.e. preventing parasite necrosis. 相似文献
36.
A summary pollen diagram and old cartographic materials were used to reconstruct the recent vegetation history and trends of temporal dynamics of the North Adriatic Karst grasslands. Before the Roman period some evidence about grassland vegetation exists from Neolithic settlements, but deforestation, detectable on the landscape level because of pollen, started 2500-2000 years BP. A large-scale anthropogenically-driven process of clearance started in the Roman period as is reflected in the increasing pollen of grasses (Poaceae) and other herbaceous species (Apiaceae). The presence of pioneer trees (Quercus, Ostrya), juniper and grasses during 1000-400 years BP suggests that cycling processes of cultivation (strong grazing pressure), abandonment and re-cultivation were present. A 250-year-old map shows a peak of probable deforestation, where grasslands have 3.2 times larger surface area than on a recent land-use map in a 665.8 km2 large pilot area. More than 60% of grasslands changed into forest since then. On a sub-plot area of 626 ha (1% of the pilot area), where habitat mappings were performed, only 12.8% were still grasslands without tall herb invasions or scrub encroachments. Another 27.1% were grasslands with early signs of reforestation. The traditionally open landscape of the North Adriatic Karst was able to recover to forest due to almost total abandonment and sufficient mesic climate conditions. 相似文献
37.
Bongartz LG Joles JA Verhaar MC Cramer MJ Goldschmeding R Tilburgs C Gaillard CA Doevendans PA Braam B 《American journal of physiology. Heart and circulatory physiology》2012,302(3):H845-H854
Coexistence of chronic kidney disease (CKD) and heart failure (HF) in humans is associated with poor outcome. We hypothesized that preexistent CKD worsens cardiac outcome after myocardial infarction, and conversely that ensuing HF worsens progression of CKD. Subtotally nephrectomized (SNX) or sham-operated (CON) rats were subjected to coronary ligation (CL) or sham surgery in week 9 to realize four groups: CON, SNX, CON + CL, and SNX + CL. Blood pressure and renal function were measured in weeks 8, 11, 13, and 15. In week 16, cardiac hemodynamics and end-organ damage were assessed. Blood pressure was significantly lower in SNX + CL vs. SNX. Despite this, glomerulosclerosis was more severe in SNX + CL vs. SNX. Two weeks after CL, SNX + CL had more cardiac dilatation compared with CON + CL (end-diastolic volume index: 0.28 ± 0.04 vs. 0.19 ± 0.03 ml/100 g body wt; mean ± SD, P < 0.001), although infarct size was similar. During follow-up in SNX + CL, ejection fraction declined. Mortality was only observed in SNX + CL (2 out of 9). In SNX + CL, end-diastolic pressure (18 ± 4 mmHg) and tau (29 ± 9 ms), the time constant of active relaxation, were significantly higher compared with SNX (13 ± 3 mmHg, 20 ± 4 ms; P < 0.01) and CON + CL (11 ± 5 mmHg, 17 ± 2 ms; P < 0.01). The diameter of small arterioles in the myocardium was significantly decreased in SNX + CL vs. CON + CL (P < 0.01). Urinary excretion of NO metabolites was significantly lower in SNX + CL compared with both CL and SNX. This study demonstrates the existence of more heart and more kidney damage in a new model of combined CKD and HF than in the individual models. Such enhanced damage appears to be separate from systemic hemodynamic changes. Reduced nitric oxide availability may have played a role in both worsened glomerulosclerosis and cardiac diastolic function and appears to be a connector in the cardiorenal syndrome. 相似文献
38.
The paper presents a method for syndromic surveillance of an epidemic outbreak due to an emerging disease, formulated in the context of stochastic nonlinear filtering. The dynamics of the epidemic is modeled using a stochastic compartmental epidemiological model with inhomogeneous mixing. The syndromic (typically non-medical) observations of the number of infected people (e.g. visits to pharmacies, sale of certain products, absenteeism from work/study, etc.) are assumed available for monitoring and prediction of the epidemic. The state of the epidemic, including the number of infected people and the unknown parameters of the model, are estimated via a particle filter. The numerical results indicate that the proposed framework can provide useful early prediction of the epidemic peak if the uncertainty in prior knowledge of model parameters is not excessive. 相似文献
39.
Chan RK Bojovic B Talbot SG Weiss D Pribaz JJ 《Plastic and reconstructive surgery》2012,129(1):119-122
Oral incompetence following composite reconstruction of total and subtotal lower lip defects without any functioning lower lip muscle is a difficult problem for reconstructive surgeons. The authors retrospectively reviewed the use of a novel bilateral temporalis suspension technique for oral incompetence following lower lip reconstruction over a 10-year period. The timing of the reconstruction, cause of the defect, period of follow-up, and any complications were noted. Three cases of lower lip resuspension using bilateral temporalis flaps and fascia lata grafts were performed from 2000 to 2010. Two cases were secondary to burn trauma and one was from ballistic trauma. All patients underwent traditional means of reconstruction using free microvascular composite tissue transfer with and without fascial slings. All three patients presented with persistent lower lip incompetence. The average interval between the initial reconstructive operations and the resuspension operations was 1.6 years. All patients achieved dynamic oral competence at the first postoperative visit. At a mean follow-up of 3.6 years, all patients had maintained lower lip function. Dynamic lower lip resuspension with bilateral temporalis flaps and fascia lata grafts is an option for refractory lower lip drooping following total and subtotal loss, especially after conventional static reconstruction and without any functional orbicularis muscle. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V. 相似文献
40.
Short tandem repeats (STRs) are subjected to two kinds of mutational modifications: point mutations and replication slippages.
The latter is found to be the more frequent cause of STR modifications, but a satisfactory quantitative measure of the ratio
of the two processes has yet to be determined. The comparison of entire genome sequences of closely enough related species
enables one to obtain sufficient statistics by counting the differences in the STR regions. We analyzed human–chimpanzee DNA
sequence alignments to obtain the counts of point mutations and replication slippage modifications. The results were compared
with the results of a computer simulation, and the parameters quantifying the replication slippage probability as well as
the probabilities of point mutations within the repeats were determined. It was found that within the STRs with repeated units
consisting of one, two or three nucleotides, point mutations occur approximately twice as frequently as one would expect on
the basis of the 1.2% difference between the human and chimpanzee genomes. As expected, the replication slippage probability
is negligible below a 10-bp threshold and grows above this level. The replication slippage events outnumber the point mutations
by one or two orders of magnitude, but are still lower by one order of magnitude relative to the mutability of the markers
that are used for genotyping purposes. 相似文献