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31.
Waardenburg Syndrome (WS) is an autosomal, dominantly inherited disorder that accounts for more than 2% cases of congenital deafness. The aim of this study is to determine the WS incidence among deaf pupils. Dysmorphological examination was performed on 720 children who were attending 7 special schools in Turkey and who had hearing disabilities. All subjects in the study were examined for WS diagnostic criteria. We detected 49 patients (6.8%) with WS among the 720 children examined. Six patients had WS type 1 (12.2%) and 43 had type 2 (87.8%). We observed 2 to 5 major diagnostic criteria for WS. Out of all the subjects in the study, only two patients have deaf first degree relatives. All subjects had been previously examined by physicians for deafness but none of them had been then diagnosed to have Waardenburg Syndrome. Instead, they were all misdiagnosed as to have nonsyndromic deafness. Awareness of WS diagnostic criteria by the physicans will provide accurate diagnosis for many deaf pupils and their first degree relatives who are able-to-hear WS patients and whose children are at risk for deafness.  相似文献   
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In this study, we investigated the effects of erythropoietin (Epo), and pentoxifylline (Ptx) on the oxidant and antioxidant systems in the experimental short bowel syndrome. Spraque-Dawley rats were divided into four groups and all animals underwent 75% small bowel resection. Group E was treated with 500 IU kg(- 1) Epo subcutaneously (s.c.), group P with 50 mg kg(- 1) day(- 1) s.c. Ptx and group E+P with 500 IU kg(- 1) s.c. Epo plus 50 mg kg(- 1) day(- 1) s.c. Ptx for a period of 28 days. In group C, which is the control group, no drug treatment was given. At the end of 28 days the experimented rats were killed and ileum samples excised for biochemical and histopathological testing. Malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were determined in ileum homogenates. When compared to group C, the MDA and GSH-Px levels were significantly decreased (p < 0.05), but SOD activity was not changed (p > 0.05) in groups P and E+P, whereas both MDA and SOD and also GSH-Px activities were not changed significantly in group E (p > 0.05). The average villous length, crypt depth, muscular thickness and mucosal length were measured in all groups. The average crypt depth and mucosal length were statistically higher in the group P than group C (p < 0.001, p < 0.01, respectively). In addition, the crypt depth was statistically higher in both E and E+P groups as compared to group C (p < 0.001, p < 0.01, respectively). Therefore, our study indicates that Ptx may be more effective than Epo in reducing lipid peroxidation. Moreover, we considered that Ptx may give this protective effect by inhibiting the free oxygen radicals to a greater extent than developing the antioxidant capacity.  相似文献   
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OBJECTIVE: To evaluate the relationship between corneoconjunctival calcification and conjunctival squamous metaplasia in patients with chronic renal failure (CRP). STUDY DESIGN: We studied impression cytology in 45 CRF patients on regular hemodialysis and 30 age- and sex-matched controls. Specimens were obtainedfrom the temporal bulbar conjunctiva using cellulose acetate filter paper. The samples were fixed in a mixture of 70% ethyl alcohol, 37% formaldehyde and glacial acetic acid and then stained with a combination of periodic acid- Schiff and Gill's modified Papanicolaou stain and graded by a masked observer. Corneoconjunctival calcification was graded by the Porter-Crombie classification. RESULTS: Of 45 study patients, 4 (9%) disclosed grade 0, 23 (51%) grade 1, 14 (31%) grade 2 and 4 grade 3 (9%) impression cytology changes. There was a statistically significant difference between the patient and control groups (p < 0.001). Calcium deposits were more frequent and extensive in CRF patients than in controls (p = 0.01). There was no correlation between impression cytology and calcium deposit grades (p = 0.128). However the presence of conjunctival inflammation correlated with the existence of extensive squamous metaplasia (p < 0.001). CONCLUSION: The severity of conjunctival changes in CRF patients on regular hemodialysis are not related to calcium deposition but to acute conjunctival inflammation.  相似文献   
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This paper presents the results of an anthropometrical survey conducted on male and female children aged 3, 4 and 5 years in Turkey. A set of 18 body dimensions was taken from 154 males and 132 females. It is considered that the 18 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual and circulatory problems resulting from badly designed elements. This study identified significant gender differences in a set of 18 anthropometrical measures in this subject group.  相似文献   
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Peter Figueroa and co-authors advocate for equity in the worldwide provision of COVID-19 vaccines.

Many may not be aware of the full extent of global inequity in the rollout of Coronavirus Disease 2019 (COVID-19) vaccines in response to the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic. As of June 20, 2021, only 0.9% of those living in low-income countries and less than 10% of those in low- and middle-income countries (LMICs) had received at least 1 dose of a COVID-19 vaccine compared with 43% of the population living in high-income countries (HICs) [1] (Fig 1). Only 2.4% of the population of Africa had been vaccinated compared with 41% of North America and 38% of Europe [1,2] (S1 Fig). Primarily due to the inability to access COVID-19 vaccines, less than 10% of the population in as many as 85 LMICs had been vaccinated compared with over 60% of the population in 26 HICs [1]. Only 10 countries account for more than 75% of all COVID-19 vaccines administered [3]. This striking and ongoing inequity has occurred despite the explicit ethical principles affirming equity of access to COVID-19 vaccines articulated in WHO SAGE values framework [4,5] prepared in mid-2020, well prior to the availability of COVID-19 vaccines.Open in a separate windowFig 1Proportion of people vaccinated with at least 1 dose of COVID-19 vaccine by income (April 14 to June 23, 2021).Note: Data on China appeared on the database on June 9, hence the jump in upper middle-income countries. COVID-19, Coronavirus Disease 2019. Source: https://ourworldindata.org/covid-vaccinations.The COVID-19 pandemic highlights the grave inequity and inadequacy of the global preparedness and response to serious emerging infections. The establishment of the Coalition for Epidemic Preparedness Innovations (CEPI) in 2018, the Access to COVID-19 Tools Accelerator (ACT-A), and the COVID-19 Vaccines Global Access (COVAX) Facility in April 2020 and the rapid development of COVID-19 vaccines were all positive and extraordinary developments [6]. The COVAX Facility, as of June 2021, has delivered approximately 83 million vaccine doses to 75 countries, representing approximately 4% of the global supply, and one-fifth of this was for HICs [7]. The COVAX Facility has been challenged to meet its supply commitments to LMICs due to insufficient access to doses of COVID-19 vaccines with the prerequisite WHO emergency use listing (EUL) or, under exceptional circumstances, product approval by a stringent regulatory authority (SRA) [8,9]. Because of the anticipated insufficient COVID-19 vaccine supply through the COVAX Facility, the majority of nonvaccine-producing LMIC countries made the decision, early in the COVID-19 pandemic, to secure and use vaccines produced in China or Russia prior to receipt of WHO EUL or SRA approval. Most of the vaccines used in LMICs as of June 20, 2021 (nearly 1.5 billion doses of the 2.6 billion doses administered) were neither WHO EUL or SRA approved at the time they were given [10]. This may raise possible concerns with respect to the effectiveness, safety, and acceptability of individual vaccines used by many countries [8,9].  相似文献   
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Quantum-mechanical equations are derived that are particularly well suited to actual computations of the CD for helical polymers. They make use of cyclic boundary conditions and helical symmetry, so that only two matrices with a size equal to the number of transitions considered need be diagonalized. The final equations are expressed directly in terms of monomer properties and helical parameters to invite the same input as earlier calculations, and are given as a rotational strength times a shape function for ease of comparison with the earlier work. The shape of the helix term is expressed as a derivative with respect to ω and depends on the distance between monomers along the helix axis. Other terms involving two electric transition dipoles depend on the distance from the helix axis to the transition center. These equations are directly comparable to the classical equations derived for cyclic boundary conditions and helical symmetry. We present an outline of the derivation and enough intermediate steps to clarify how the equations arise.  相似文献   
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Aim Natural processes of colonization and human‐mediated introductions have shaped current patterns of biodiversity in the Mediterranean Basin. We use a comparative phylogeographic approach to investigate the genetic structure of Herpestes ichneumon and Genetta genetta (Carnivora) across the Strait of Gibraltar, and test for their supposedly contemporaneous introduction into Iberia. Location Mediterranean Basin and Africa. Methods We sequenced two mitochondrial fragments (cytochrome b and control region) of 91 (H. ichneumon) and 185 (G. genetta) individuals, including the sole archaeological record of G. genetta in Iberia, dating from the Muslim occupation. We used phylogenetic and tokogenetic methods, summary statistics, neutrality tests, geographic–genetic pairwise comparisons and coalescent estimates to explore the history of the two species in the Mediterranean Basin. Results In North Africa, an autochthonous (Clade I) and a western African mtDNA clade, coalescing in the Middle to Late Pleistocene, co‐occurred in both species. Only Clade I was present in Europe. In H. ichneumon, the European pool showed deep coalescence (median = 335 kyr) and high genetic differentiation and diversity compared with its North African counterpart, suggesting long‐term stability of female effective population size. In sharp contrast, G. genetta in Europe exhibited lower genetic diversity, weak differentiation with North Africa and recent demographic expansion; however, Andalusia and Catalonia (Spain) showed distinctly higher genetic diversity, and the archaeological specimen had the predominant European haplotype. Main conclusions The co‐occurrence of autochthonous and sub‐Saharan lineages in North Africa (1) supports a new, emerging biogeographic scenario in North Africa, and (2) suggests a connection through the Sahara, possibly from the Middle Pleistocene onwards. Our results refute the idea that H. ichneumon was introduced into Europe contemporaneously with G. genetta. Instead, they support a scenario of sweepstake dispersal during Late Pleistocene sea‐level fluctuations, followed by long‐term in situ evolution throughout the last glaciation cycles. Genetta genetta appears to have undergone a recent spread from at least two independent introduction ‘hotspots’ in Catalonia and Andalusia, possibly following antique trade routes and/or Muslim invasions. Despite their contrasting histories, the European gene pools of both species represent unusual cases leading to the preservation of autochthonous, North African lineages.  相似文献   
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