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61.
The 62-channel EEG was recorded while control non-alexithymic (n = 21) and alexithymic (n = 20) participants viewed sequentially presented neutral, pleasant and unpleasant pictures and subjectively rated them after each presentation. The event-related synchronization (ERS) to these stimuli was assessed in the theta-1 (4-6 Hr) and theta-2 (6-8 Hz) frequency bands. The obtained findings indicate that alexithymia influences perception of only emotional stimuli. In the upper theta over anterior cortical regions alexithymia vs control individuals in response to both pleasant and unpleasant stimuli manifested decreased left hemisphere ERS in the early test period of 0-200 ms along with enhanced ERS in response to negative vs positive and neutral stimuli in the right hemisphere at 200-600 ms after stimulus onset. The findings provide the first EEG evidence that alexithymia construct, associated with a cognitive deficit in initial evaluation of emotion, is indexed by disrupted early frontal synchronization in the upper theta band that can be best interpreted to reflect disregulation during appraisal of emotional stimuli.  相似文献   
62.
The study determined the contribution of activity balance of the two motivational systems, i.e. appetitive and defensive, into mechanisms of blood pressure (BP) regulation in humans. Average age of participants was 30.29 +/- 9.8 years. Men having the BP within normal range and the individuals with firstly diagnosed increased arterial blood pressure up to abnormal values were selected. Using the method of emotional modulation of the startle reflex (EMSR) by different profiles of the EMSR. The participants with shifted balance toward enhanced activity of defensive system (amplified probe startle by unpleasant context) or shifted balance toward low activity of appetitive system (decrease or inhibition of the probe startle by pleasant context) had significantly increased BP in resting. Putative mechanisms of the revealed phenomena are discussed.  相似文献   
63.
We present an algorithm to build self-avoiding lattice models of chain molecules with low RMS deviation from their actual 3D structures. To find the optimal coordinates for the lattice chain model, we minimize a function that consists of three terms: (1) the sum of squared deviations of link coordinates on a lattice from their off-lattice values, (2) the sum of “short-range” terms, penalizing violation of chain connectivity, and (3) the sum of “long-range” repulsive terms, penalizing chain self-intersections. We treat this function as a chain molecule “energy” and minimize it using self-consistent field (SCF) theory to represent the pairwise link repulsions as 3D fields acting on the links. The statistical mechanics of chain molecules enables computation of the chain distribution in this field on the lattice. The field is refined by iteration to become self-consistent with the chain distribution, then dynamic programming is used to find the optimal lattice model as the “lowest-energy” chain pathway in this SCF. We have tested the method on one of the coarsest (and most difficult) lattices used for model building on proteins of all structural types and show that the method is adequate for building self-avoiding models of proteins with low RMS deviations from the actual structures. © 1996 Wiley-Liss, Inc.  相似文献   
64.
A general approach is developed to search for stable structures of short chain fragments (e.g. of loops or bound oligopeptides) in a given molecular field. This molecular field is produced by the remaining part of a globule or by any other surface with a defined spatial structure. The fragment must be short enough to have no pronounced long-range interactions within itself. The method is illustrated by calculation of the 3-D structures of two loops of bovine pancreatic trypsin inhibitor (BPTI). Computations are based on a lattice model of conformational space and on strict and fast algorithms of 1-D statistical mechanics and dynamic programming (which are very similar in essence). This makes a search of oligopeptide structures only several times (and not several orders of magnitude) longer than that of a dipeptide.  相似文献   
65.
Cathepsin D was isolated from the grey matter of bovine and porcine large cerebral hemispheres and purified by affinity chromatography on haemoglobin--Sepharose. The isolation and purification of the enzyme also included: acidic extraction, precipitation by ammonium sulfate, dialysis, affinity chromatography, concentration and gel-chromatography on Sephadex G-100. The degree of purification of bovine cerebral enzyme was 3280. The Km value for the enzyme was 2,06 . 10(-5) M. The purified enzyme from bovine brain showed three major and two minor adjacent bands, possessing the cathepsin D activities. The purified enzyme from porcine brain showed only one protein band.  相似文献   
66.
The complete genome sequence of Bacillus amyloliquefaciens type strain DSM7T is presented. A comparative analysis between the genome sequences of the plant associated strain FZB42 (Chen et al., 2007) with the genome of B. amyloliquefaciens DSM7T revealed obvious differences in the variable part of the genomes, whilst the core genomes were found to be very similar. The strains FZB42 and DSM7T have in common 3345 genes (CDS) in their core genomes; whilst 547 and 344 CDS were found to be unique in DSM7T and FZB42, respectively. The core genome shared by both strains exhibited 97.89% identity on amino acid level. The number of genes representing the core genome of the strains FZB42, DSM7T, and Bacillus subtilis DSM10T was calculated as being 3098 and their identity was 92.25%. The 3,980,199 bp genome of DSM7T contains numerous genomic islands (GI) detected by different methods. Many of them were located in vicinity of tRNA, glnA, and glmS gene copies. In contrast to FZB42, but similar to B. subtilis DSM10T, the GI were enriched in prophage sequences and often harbored transposases, integrases and recombinases. Compared to FZB42, B. amyloliquefaciens DSM7T possessed a reduced potential to non-ribosomally synthesize secondary metabolites with antibacterial and/or antifungal action. B. amyloliquefaciens DSM7T did not produce the polyketides difficidin and macrolactin and was impaired in its ability to produce lipopeptides other than surfactin. Differences established within the variable part of the genomes, justify our proposal to discriminate the plant-associated ecotype represented by FZB42 from the group of type strain related B. amyloliquefaciens soil bacteria.  相似文献   
67.
Campylobacter jejuni has recently been noted as the most common cause of bacterial foodborne diseases in Japan. In the present study, we determined ST types of C. jejuni and Campylobacter coli isolated from chickens and patients with enteritis or GBS in Japan and Thailand. C. jejuni from chickens, enteritis, and GBS exhibited divergent ST types and included several novel types in addition to worldwide common types. C. coli from enteritis was also divergent. Novel ST types may represent unidentified native clones in each country. Pulsed‐field gel electrophoresis confirmed the above typing and demonstrated long‐term persistence and transmission.  相似文献   
68.
Helicobacter pylori in Vladivostok, Far Eastern Russia, was investigated during 2004 to 2009. The genotype cagA(+) vacA(+) (s1/m1 or m2) accounted for 74.7%, with cagA(-) vacA(+) (s2/m2) at 11.2%. The CagA EPIYA type was mainly Western ABC, with minor types (ABCCC and novel AAABC) or non-Western/non-East Asia type (AB). Regarding drug resistance, metronidazole resistance was the highest, with a marked decrease in 6 years (from 71.4% to 30.8%); in contrast, levofloxacin and clarithromycin resistance increased. The data indicate that in Vladivostok, H. pylori was mainly the Western (not East Asian) type and dynamic changes in drug resistance occurred during 6 years.  相似文献   
69.
Two of thirteen bacillar strains isolated from the inner tissues of cotton plants were found to produce type II restriction endonucleases. The investigation of the site specificity of these enzymes showed that they are AsuI and Eco31I isoschizomers.  相似文献   
70.

Background

Currently there is a lot of debate about the advantages and disadvantages of for-profit health care delivery. We examined staffing ratios for direct-care and support staff in publicly funded not-for-profit and for-profit nursing homes in British Columbia.

Methods

We obtained staffing data for 167 long-term care facilities and linked these to the type of facility and ownership of the facility. All staff were members of the same bargaining association and received identical wages in both not-for-profit and for-profit facilities. Similar public funding is provided to both types of facilities, although the amounts vary by the level of functional dependence of the residents. We compared the mean number of hours per resident-day provided by direct-care staff (registered nurses, licensed practical nurses and resident care aides) and support staff (housekeeping, dietary and laundry staff) in not-for-profit versus for-profit facilities, after adjusting for facility size (number of beds) and level of care.

Results

The nursing homes included in our study comprised 76% of all such facilities in the province. Of the 167 nursing homes examined, 109 (65%) were not-for-profit and 58 (35%) were for-profit; 24% of the for-profit homes were part of a chain, and the remaining homes were owned by a single operator. The mean number of hours per resident-day was higher in the not-for-profit facilities than in the for-profit facilities for both direct-care and support staff and for all facility levels of care. Compared with for-profit ownership, not-for-profit status was associated with an estimated 0.34 more hours per resident-day (95% confidence interval [CI] 0.18–0.49, p < 0.001) provided by direct-care staff and 0.23 more hours per resident-day (95% CI 0.15–0.30, p < 0.001) provided by support staff.

Interpretation

Not-for-profit facility ownership is associated with higher staffing levels. This finding suggests that public money used to provide care to frail eldery people purchases significantly fewer direct-care and support staff hours per resident-day in for-profit long-term care facilities than in not-for-profit facilities.Nnursing homes provide long-term housing, support and direct care to members of the community who are unable to function independently because of medical, physical and cognitive disabilities. Although only a small proportion of older Canadians reside in nursing homes (18% of those ≥ 80 years), the majority (81%) of long-term care residents are frail elderly people over the age of 65.1Government-funded long-term care in Canada has been provided for many years by a mix of not-for-profit (nonproprietary) and for-profit (proprietary) facilities. The ratio of this mix varies greatly by province. For example, in Ontario 52% of publicly funded nursing homes are for-profit, as compared with 15% in Manitoba.2Previous studies from the United States have shown that having more direct-care personnel is associated with better care in nursing homes.3,4,5,6,7 Specifically, higher numbers of registered-nurse hours per resident-day have been associated with fewer violations of care standards4 and improved functional ability of residents.7 Schnelle and colleagues examined 21 nursing homes in California and found that the homes with the highest number of nurse aides performed significantly better in 13 of 16 quality-of-care measures than the homes with fewer nurse aides.6 Although there has been little research on staffing levels and nursing home care in other countries, health policy-makers in the United Kingdom8 and Australia9 have begun to call for greater accountability for public resources spent in this area.The American literature has also shown that, compared with for-profit nursing homes, not-for-profit facilities have higher direct-care staffing levels4 and lower staff turnover rates.10,11 However, the majority of nursing home care in the United States is delivered by the for-profit sector, whereas in Canada the not-for-profit sector constitutes the majority. This may result in a difference in the informal benchmarks for staffing levels between the 2 countries. There also may be a wider variation in wages and working conditions among nursing homes in the United States, which potentially confounds the comparison between for-profit and not-for-profit facilities.We compared staffing levels of nursing and support staff in publicly funded long-term care facilities by ownership type (not-for-profit v. for-profit) in British Columbia at a time when the majority of publicly funded not-for-profit and for-profit facilities employed a unionized labour force with standardized wages and benefits set by a master collective agreement.In British Columbia, approximately 70% of publicly funded nursing homes are nonproprietary (not-for-profit) and 30% are proprietary (for-profit). Both not-for-profit and for-profit facilities receive global funding from the provincial government on the basis of (a) the level of functional dependence of facility residents and (b) the percentage of fees borne by residents according to their income levels. At the time of the study (2001), there was no regulation by government or the regional health authorities as to how individual facilities allocated funding between staffing, administration or property costs.Not-for-profit long-term care in British Columbia is delivered by religious, cultural or other community-based societies, by regional health authorities or by publicly owned acute care hospitals. For-profit care is delivered by sole operators or by facilities that are part of larger business entities (chains). Nursing homes are grouped by levels of care according to the residents'' case-mix: intermediate care only (IC), intermediate and extended care (IC & EC), multi-level care, or extended care only. IC facilities provide care for people with relatively more functional ability, whereas extended care facilities accommodate the most functionally dependent people. The other 2 facility types provide care for people with a mix of functional abilities.  相似文献   
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