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101.
The purpose of this study was to obtain information on the dietary knowledge of primary health care workers and on their ability to apply this knowledge in practice. A total of 128 primary health care workers (53 general practitioners and 61 nurses) in 12 practices and 14 primary care facilitators were surveyed by questionnaire between December 1987 and June 1988. All of the practices were participating in a project to promote prevention in primary care and offered health checks designed to identify and deal with cardiovascular risk factors. The questionnaire focused on issues related to managing patients with moderate hypercholesterolaemia. The results of the study showed some important gaps in the health workers'' knowledge--for example, only 91 understood that dietary intake of polyunsaturated fatty acids as a proportion of total fat intake should be increased in a diet designed to reduce serum lipid concentrations. Appreciable gaps in their ability to give practical and appropriate dietary advice were also identified: 35 gave advice that would have led to the patient losing weight (although his history indicated that he was not overweight), and 27 gave only negative advice, offering no suggestions about substituting healthy foods for unhealthy ones. The demand for primary health care workers to give dietary advice is increasing and is likely to increase further if a national screening programme for hypercholesterolaemia is recommended. The results of this survey point to a need for improved nutritional education and training in dietary counselling for general practitioners, nurses, and primary care facilitators.  相似文献   
102.
The germline polymorphisms in signal-inducing proliferation-associated protein 1 (SIPA1) and ribosomal RNR processing 1B (RRP1B) might be involved in breast cancer metastasis. The aim of this study was to analyze how SIPA1 and RRP1B polymorphisms contribute to breast cancer phenotype, lymph node status and survival. A group of 100 young, I–II stage breast cancer patients were analyzed for SIPA1 and RRP1B polymorphisms with PCR-RFLP assay. SIPA1 c.2760G?>?A, c.545C?>?T and RRP1B c.436T?>?C polymorphisms were associated with lymph node status, survival and tumor grade, respectively. Our results suggest that SIPA1 and RRP1B germline polymorphisms are important for breast cancer prognosis.  相似文献   
103.
104.
Data on the abundance of heterotrophic bacteria on the surface of artificially incubated noble crayfish (Astacus astacus L.) eggs are presented. The highest abundance of heterotrophic bacteria was observed on crayfish juveniles (stage 1). The abundance of bacteria in the water of the incubator’s system was found to be considerably lower than that on crayfish eggs, and bacteria counts on dead eggs were a 100 times lower than on healthy eggs. The abundance of pigmented bacteria on dead eggs was considerably higher than on healthy eggs. Aeromonas and Pseudomonas bacteria, constituting up to 70% of all bacteria identified, were found to be dominant on noble crayfish eggs.  相似文献   
105.
106.
GS10 [cyclo-(VKLdYPVKLdYP)] is a synthetic analog of the naturally occurring antimicrobial peptide gramicidin (GS) in which the two positively charged ornithine (Orn) residues are replaced by two positively charged lysine (Lys) residues and the two less polar aromatic phenylalanine (Phe) residues are replaced by the more polar tyrosine (Tyr) residues. In this study, we examine the effects of these seemingly conservative modifications to the parent GS molecule on the physical properties of the peptide, and on its interactions with lipid bilayer model and biological membranes, by a variety of biophysical techniques. We show that although GS10 retains the largely β-sheet conformation characteristic of GS, it is less structured in both water and membrane-mimetic solvents. GS10 is also more water soluble and less hydrophobic than GS, as predicted, and also exhibits a reduced tendency for self-association in aqueous solution. Surprisingly, GS10 associates more strongly with zwitterionic and anionic phospholipid bilayer model membranes than does GS, despite its greater water solubility, and the presence of anionic phospholipids and cholesterol (Chol) modestly reduces the association of both GS10 and GS to these model membranes. The strong partitioning of both peptides into lipid bilayers is driven by a large favorable entropy change opposed by a much smaller unfavorable enthalpy change. However, GS10 is also less potent than GS at inducing inverted cubic phases in phospholipid bilayer model membranes and at inhibiting the growth of the cell wall-less bacterium Acholeplasma laidlawii B. These results are discussed in terms of the comparative antibiotic and hemolytic activities of these peptides.  相似文献   
107.
The PSI-G subunit of photosystem I (PSI) is an 11-kDa membrane protein that plays an important role in electron transport between plastocyanin and PSI and is involved in the stability of the PSI complex. Within the complex, the PSI-G subunit is bound to PSI-B and is in contact with Lhca1. PSI-G has two transmembrane spans connected by a positively charged stromal loop. The loop is inaccessible to proteases, indicating a tightly bound location within the PSI complex. Here, we have studied the insertion mechanism and assembly of PSI-G. We show that the protein inserts into thylakoids by a direct or "spontaneous" pathway that does not involve the activities of any known chloroplast protein-targeting machinery. Surprisingly, the positively charged stromal loop region plays a major role in this process. Mutagenesis or deletions within this region almost invariably lead to a marked lowering of insertion efficiency, strongly indicating a critical role for the loop in the organization of the transmembrane regions prior to or during membrane insertion. Finally, we have examined the assembly of newly inserted PSI-G into the PSI complex, since very little is known of the assembly pathway for this large multimeric complex. Interestingly, we find that inserted PSI-G can be found within the full PSI complex within the import assay time frame after insertion into thylakoids, strongly suggesting that PSI-G normally associates at the end of the assembly process. This is consistent with its location on the periphery of the complex.  相似文献   
108.
Escapement success and migration patterns of silver eels Anguilla anguilla (L.) was studied by acoustic telemetry in three natural free‐flowing and one dammed river and in Curonian Lagoon in Lithuania. Mean downstream migration speed and escapement success were almost the same in the shorter 210 km dammed river (52%, 13.6 km/day) and the considerably longer 300–480 km free‐flowing rivers (53%, 10.7 km/day). Despite the similarity between migration speed in the Curonian Lagoon (14.6 km/day) to that in rivers, migration success was significantly higher (71%) in the Lagoon. Although a majority of silver eels in Lithuania start migrating downstream in spring, the peak of eel migration into the Baltic Sea was observed during late fall. Overall migration success in the rivers and the Lagoon was 35%. Relatively low escapement may have negative consequences on the success on eel stock restoration and must be addressed when strategically planning for the production of spawners.  相似文献   
109.

Background

People who rate their health as poor experience higher all-cause mortality. Study of disease-specific association with self-rated health might increase understanding of why this association exists.

Objectives

To estimate the strength of association between self-rated health and fatal and non-fatal cardiovascular disease.

Methods

A comprehensive search of PubMed MEDLINE, EMBASE, CINAHL, BIOSIS, PsycINFO, DARE, Cochrane Library, and Web of Science was undertaken during June 2013. Two reviewers independently searched databases and selected studies. Inclusion criteria were prospective cohort studies or cohort analyses of randomised trials with baseline measurement of self-rated health with fatal or non-fatal cardiovascular outcomes. 20 studies were pooled quantitatively in different meta-analyses. Study quality was assessed using Newcastle-Ottawa scales.

Results

‘Poor’ relative to ‘excellent’ self-rated health (defined by most extreme categories in each study, most often’ poor’ or ‘very poor’ and ‘excellent’ or ‘good’) was associated over a follow-up of 2.3–23 years with cardiovascular mortality in studies: where varying degrees of adjustments had been made for cardiovascular disease risk (HR 1.79 (95% CI 1.50 to 2.14); 15 studies, I2 = 71.24%), and in studies reporting outcomes in people with pre-existing cardiovascular disease or ischaemic heart disease symptoms (HR 2.42 (95% CI 1.32 to 4.44); 3 studies; I2 = 71.83%). ‘Poor’ relative to ‘excellent’ self rated health was also associated with the combined outcome of fatal and non-fatal cardiovascular events (HR 1.90 (95% CI 1.26 to 2.87); 5 studies; I2 = 68.61%), Self-rated health was not significantly associated with non-fatal cardiovascular disease outcomes (HR 1.66 (95% CI 0.96 to 2.87); 5 studies; I2 = 83.60%).

Conclusions

Poor self rated health is associated with cardiovascular mortality in populations with and without prior cardiovascular disease. Those with current poor self-rated health may warrant additional input from health services to identify and address reasons for their low subjective health.  相似文献   
110.
Background:Otitis media with effusion is a common problem that lacks an evidence-based nonsurgical treatment option. We assessed the clinical effectiveness of treatment with a nasal balloon device in a primary care setting.Methods:We conducted an open, pragmatic randomized controlled trial set in 43 family practices in the United Kingdom. Children aged 4–11 years with a recent history of ear symptoms and otitis media with effusion in 1 or both ears, confirmed by tympanometry, were allocated to receive either autoinflation 3 times daily for 1–3 months plus usual care or usual care alone. Clearance of middle-ear fluid at 1 and 3 months was assessed by experts masked to allocation.Results:Of 320 children enrolled, those receiving autoinflation were more likely than controls to have normal tympanograms at 1 month (47.3% [62/131] v. 35.6% [47/132]; adjusted relative risk [RR] 1.36, 95% confidence interval [CI] 0.99 to 1.88) and at 3 months (49.6% [62/125] v. 38.3% [46/120]; adjusted RR 1.37, 95% CI 1.03 to 1.83; number needed to treat = 9). Autoinflation produced greater improvements in ear-related quality of life (adjusted between-group difference in change from baseline in OMQ-14 [an ear-related measure of quality of life] score −0.42, 95% CI −0.63 to −0.22). Compliance was 89% at 1 month and 80% at 3 months. Adverse events were mild, infrequent and comparable between groups.Interpretation:Autoinflation in children aged 4–11 years with otitis media with effusion is feasible in primary care and effective both in clearing effusions and improving symptoms and ear-related child and parent quality of life. Trial registration: ISRCTN, No. 55208702.Otitis media with effusion, also known as glue ear, is an accumulation of fluid in the middle ear, without symptoms or signs of an acute ear infection. It is often associated with viral infection.13 The prevalence rises to 46% in children aged 4–5 years,4 when hearing difficulty, other ear-related symptoms and broader developmental concerns often bring the condition to medical attention.3,5,6 Middle-ear fluid is associated with conductive hearing losses of about 15–45 dB HL.7 Resolution is clinically unpredictable,810 with about a third of cases showing recurrence.11 In the United Kingdom, about 200 000 children with the condition are seen annually in primary care.12,13 Research suggests some children seen in primary care are as badly affected as those seen in hospital.7,9,14,15 In the United States, there were 2.2 million diagnosed episodes in 2004, costing an estimated $4.0 billion.16 Rates of ventilation tube surgery show variability between countries,1719 with a declining trend in the UK.20Initial clinical management consists of reasonable temporizing or delay before considering surgery.13 Unfortunately, all available medical treatments for otitis media with effusion such as antibiotics, antihistamines, decongestants and intranasal steroids are ineffective and have unwanted effects, and therefore cannot be recommended.2123 Not only are antibiotics ineffective, but resistance to them poses a major threat to public health.24,25 Although surgery is effective for a carefully selected minority,13,26,27 a simple low-cost, nonsurgical treatment option could benefit a much larger group of symptomatic children, with the purpose of addressing legitimate clinical concerns without incurring excessive delays.Autoinflation using a nasal balloon device is a low-cost intervention with the potential to be used more widely in primary care, but current evidence of its effectiveness is limited to several small hospital-based trials28 that found a higher rate of tympanometric resolution of ear fluid at 1 month.2931 Evidence of feasibility and effectiveness of autoinflation to inform wider clinical use is lacking.13,28 Thus we report here the findings of a large pragmatic trial of the clinical effectiveness of nasal balloon autoinflation in a spectrum of children with clinically confirmed otitis media with effusion identified from primary care.  相似文献   
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