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1.
HIV Med ; 23(2): 146-158, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34605153

RESUMO

OBJECTIVES: The aim of the study was to assess the feasibility of a national pre-exposure prophylaxis (PrEP) programme using smartphone-compatible data collection. METHODS: This was a multicentre cohort study (NCT03893188) enrolling individuals interested in PrEP in Switzerland. All centres participate in the SwissPrEPared programme, which uses smartphone-compatible data collection. Feasibility was assessed after centres had enrolled at least one participant. Participants were HIV-negative individuals presenting for PrEP counselling. Outcomes were participation (number enrolled/number eligible), enrolment rates (number enrolled per month), retention at first follow-up (number with first follow-up/number enrolled), and uptake (proportion attending first visit as scheduled). Participant characteristics were compared between those retained after baseline assessment and those who dropped out. RESULTS: Between April 2019 and January 2020, 987 individuals were assessed for eligibility, of whom 969 were enrolled (participation: 98.2%). The median enrolment rate was 86 per month [interquartile range (IQR) 52-137]. Retention at first follow-up and uptake were both 80.7% (782/969 and 532/659, respectively). At enrolment, the median age was 40 (IQR 33-47) years, 95% were men who have sex with men, 47% had a university degree, and 75.5% were already taking PrEP. Most reported multiple casual partners (89.2%), previous sexually transmitted infections (74%) and sexualized drug use (73.1%). At baseline, 25.5% tested positive for either syphilis, gonorrhoea or chlamydia. Participants who dropped out were at lower risk of HIV infection than those retained after baseline assessment. CONCLUSIONS: In a national PrEP programme using smartphone-compatible data collection, participation, retention and uptake were high. Participants retained after baseline assessment were at considerable risk of HIV infection. Younger, less educated individuals were underrepresented in the SwissPrEPared cohort.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Adulto , Fármacos Anti-HIV/uso terapêutico , Estudos de Coortes , Coleta de Dados , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Smartphone
2.
HIV Med ; 20(6): 418-423, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31062497

RESUMO

OBJECTIVES: Late presentation (LP) to HIV care disproportionally affects individuals from sub-Saharan Africa (SSA). We explored the reasons for late presentation to care among this group of patients in the Swiss HIV Cohort Study. METHODS: The prevalence of LP was compared between patients from Western Europe (WE) and those from SSA enrolled between 2009 and 2012. Patients were asked about HIV testing, including access to testing and reasons for deferring it, during face-to-face interviews. RESULTS: The proportion of LP was 45.8% (435/950) among patients from WE, and 64.6% (126/195) among those from SSA (P < 0.001). Women from WE were slightly more likely to present late than men (52.6% versus 44.5%, respectively; P = 0.06), whereas there was no sex difference in patients from SSA (65.6% versus 63.2%, respectively; P = 0.73). Compared with late presenters from WE, those from SSA were more likely to be diagnosed during pregnancy (9.1% versus 0%, respectively; P < 0.001), but less likely to be tested by general practitioners (25.0% versus 44.6%, respectively; P = 0.001). Late presenters from SSA more frequently reported 'not knowing about anonymous testing possibilities' (46.4% versus 27.3%, respectively; P = 0.04) and 'fear about negative reaction in relatives' (39.3% versus 21.7%, respectively; P = 0.05) as reasons for late testing. Fear of being expelled from Switzerland was reported by 26.1% of late presenters from SSA. CONCLUSIONS: The majority of patients from SSA were late presenters, independent of sex or education level. Difficulties in accessing testing facilities, lack of knowledge about HIV testing and fear-related issues are important drivers for LP in this population.


Assuntos
Diagnóstico Tardio/estatística & dados numéricos , Emigrantes e Imigrantes , Infecções por HIV/diagnóstico , Adulto , África Subsaariana , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Prospectivos , Suíça
3.
Nat Commun ; 9(1): 2699, 2018 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-30002376

RESUMO

Fundamentally, material flow stress increases exponentially at deformation rates exceeding, typically, ~103 s-1, resulting in brittle failure. The origin of such behavior derives from the dislocation motion causing non-Arrhenius deformation at higher strain rates due to drag forces from phonon interactions. Here, we discover that this assumption is prevented from manifesting when microstructural length is stabilized at an extremely fine size (nanoscale regime). This divergent strain-rate-insensitive behavior is attributed to a unique microstructure that alters the average dislocation velocity, and distance traveled, preventing/delaying dislocation interaction with phonons until higher strain rates than observed in known systems; thus enabling constant flow-stress response even at extreme conditions. Previously, these extreme loading conditions were unattainable in nanocrystalline materials due to thermal and mechanical instability of their microstructures; thus, these anomalies have never been observed in any other material. Finally, the unique stability leads to high-temperature strength maintained up to 80% of the melting point (~1356 K).

4.
Nature ; 537(7620): 378-81, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27629642

RESUMO

Nanocrystalline metals, with a mean grain size of less than 100 nanometres, have greater room-temperature strength than their coarse-grained equivalents, in part owing to a large reduction in grain size. However, this high strength generally comes with substantial losses in other mechanical properties, such as creep resistance, which limits their practical utility; for example, creep rates in nanocrystalline copper are about four orders of magnitude higher than those in typical coarse-grained copper. The degradation of creep resistance in nanocrystalline materials is in part due to an increase in the volume fraction of grain boundaries, which lack long-range crystalline order and lead to processes such as diffusional creep, sliding and rotation. Here we show that nanocrystalline copper-tantalum alloys possess an unprecedented combination of properties: high strength combined with extremely high-temperature creep resistance, while maintaining mechanical and thermal stability. Precursory work on this family of immiscible alloys has previously highlighted their thermo-mechanical stability and strength, which has motivated their study under more extreme conditions, such as creep. We find a steady-state creep rate of less than 10(-6) per second-six to eight orders of magnitude lower than most nanocrystalline metals-at various temperatures between 0.5 and 0.64 times the melting temperature of the matrix (1,356 kelvin) under an applied stress ranging from 0.85 per cent to 1.2 per cent of the shear modulus. The unusual combination of properties in our nanocrystalline alloy is achieved via a processing route that creates distinct nanoclusters of atoms that pin grain boundaries within the alloy. This pinning improves the kinetic stability of the grains by increasing the energy barrier for grain-boundary sliding and rotation and by inhibiting grain coarsening, under extremely long-term creep conditions. Our processing approach should enable the development of microstructurally stable structural alloys with high strength and creep resistance for various high-temperature applications, including in the aerospace, naval, civilian infrastructure and energy sectors.

5.
Rev Med Suisse ; 11(470): 850-5, 2015 Apr 15.
Artigo em Francês | MEDLINE | ID: mdl-26050301

RESUMO

Few studies have examined the workload or clinical spectrum of non-HIV infectious diseases outpatient consultations (IDOC). This retrospective study aims to describe IDOC referrals over the past 5 years. In total, 483 patients were referred (with an increase of 63% between 2009 and 2013). Most referrals were received from primary care clinicians (45%). Median patient age was 47 years, 57% of patients were men and 17% were immunosuppressed. Of the diagnoses retained, 74% were infectious, 20% were non-infectious and 6% were of unknown aetiology. Two community outbreaks were identified (tattoo-related mycobacterial infection and Q fever). In conclusion, the infectious diseases outpatient clinic, which has expanded progressively in the past 5 years, provides a specialised service for primary health clinicians and for public health.


Assuntos
Assistência Ambulatorial/métodos , Doenças Transmissíveis/terapia , Pacientes Ambulatoriais , Encaminhamento e Consulta/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Transmissíveis/epidemiologia , Surtos de Doenças , Hospitais Universitários , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Suíça/epidemiologia , Adulto Jovem
6.
HIV Med ; 15(10): 631-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25102762

RESUMO

OBJECTIVES: Kaposi's sarcoma (KS), invasive cervical carcinoma (ICC) and non-Hodgkin lymphoma (NHL) have been listed as AIDS-defining cancers (ADCs) by the Centers for Disease Control and Prevention since 1993. Despite this, HIV screening is not universally mentioned in ADC treatment guidelines. We examined screening practices at a tertiary centre serving a population where HIV seroprevalence is 0.4%. METHODS: Patients with KS, ICC, NHL and Hodgkin lymphoma (HL), treated at Lausanne University Hospital between January 2002 and July 2012, were studied retrospectively. HIV testing was considered part of the oncology work-up if performed between 90 days before and 90 days after the cancer diagnosis date. RESULTS: A total of 880 patients were examined: 10 with KS, 58 with ICC, 672 with NHL and 140 with HL. HIV testing rates were 100, 11, 60 and 59%, and HIV seroprevalence was 60, 1.7, 3.4 and 5%, respectively. Thirty-seven patients (4.2%) were HIV-positive, of whom eight (22%) were diagnosed at oncology work-up. All newly diagnosed patients had CD4 counts < 200 cells/µL and six (75%) had presented to a physician 12-236 weeks previously with conditions warranting HIV testing. CONCLUSIONS: In our institution, only patients with KS were universally screened. Screening rates for other cancers ranged from 11 to 60%. HIV seroprevalence was at least fourfold higher than the population average. As HIV-positive status impacts on cancer patient medical management, HIV screening should be included in oncology guidelines. Further, we recommend that opt-out screening should be adopted in all patients with ADCs and HL.


Assuntos
Infecções por HIV/diagnóstico , Doença de Hodgkin/virologia , Linfoma não Hodgkin/virologia , Programas de Rastreamento/estatística & dados numéricos , Sarcoma de Kaposi/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Soroprevalência de HIV , Hospitais Universitários/estatística & dados numéricos , Humanos , Masculino , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Estudos Retrospectivos , Suíça/epidemiologia
7.
Zoonoses Public Health ; 61(8): 537-44, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24499160

RESUMO

Hepatitis E is considered an emerging human viral disease in industrialized countries. Studies from Switzerland report a human seroprevalence of hepatitis E virus (HEV) of 2.6-21%, a range lower than in adjacent European countries. The aim of this study was to determine whether HEV seroprevalence in domestic pigs and wild boars is also lower in Switzerland and whether it is increasing and thus indicating that this zoonotic viral infection is emerging. Serum samples collected from 2,001 pigs in 2006 and 2011 and from 303 wild boars from 2008 to 2012 were analysed by ELISA for the presence of HEV-specific antibodies. Overall HEV seroprevalence was 58.1% in domestic pigs and 12.5% in wild boars. Prevalence in domestic pigs was significantly higher in 2006 than in 2011. In conclusion, HEV seroprevalence in domestic pigs and wild boars in Switzerland is comparable with the seroprevalence in other countries and not increasing. Therefore, prevalence of HEV in humans must be related to other factors than prevalence in pigs or wild boars.


Assuntos
Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite E/veterinária , Doenças dos Suínos/epidemiologia , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Hepatite E/epidemiologia , Hepatite E/virologia , Vírus da Hepatite E/isolamento & purificação , Humanos , Masculino , Estudos Soroepidemiológicos , Sus scrofa , Suínos , Doenças dos Suínos/virologia , Suíça/epidemiologia , Zoonoses
9.
Nature ; 424(6946): 299-302, 2003 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-12867978

RESUMO

The shells of the planktonic foraminifer Neogloboquadrina pachyderma have become a classical tool for reconstructing glacial-interglacial climate conditions in the North Atlantic Ocean. Palaeoceanographers utilize its left- and right-coiling variants, which exhibit a distinctive reciprocal temperature and water mass related shift in faunal abundance both at present and in late Quaternary sediments. Recently discovered cryptic genetic diversity in planktonic foraminifers now poses significant questions for these studies. Here we report genetic evidence demonstrating that the apparent 'single species' shell-based records of right-coiling N. pachyderma used in palaeoceanographic reconstructions contain an alternation in species as environmental factors change. This is reflected in a species-dependent incremental shift in right-coiling N. pachyderma shell calcite delta18O between the Last Glacial Maximum and full Holocene conditions. Guided by the percentage dextral coiling ratio, our findings enhance the use of delta18O records of right-coiling N. pachyderma for future study. They also highlight the need to genetically investigate other important morphospecies to refine their accuracy and reliability as palaeoceanographic proxies.


Assuntos
Variação Genética/genética , Plâncton/crescimento & desenvolvimento , Plâncton/genética , Animais , Oceano Atlântico , Carbonato de Cálcio , Genótipo , Geografia , Sedimentos Geológicos , Groenlândia , Dados de Sequência Molecular , Morfogênese , Noruega , Fenótipo , Densidade Demográfica , RNA Ribossômico/genética , Especificidade da Espécie , Temperatura , Fatores de Tempo
10.
Int J Cosmet Sci ; 25(4): 183-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18494899

RESUMO

Dandruff is a common problem in approximately 30% of the world's population. Reports in the literature regarding treatment of this condition with various antidandruff shampoos usually report the level of active ingredient within the formulation. However, we propose that a more important parameter relating to antidandruff efficacy is the amount of active ingredient delivered to the scalp from the shampoo. This report describes the results from two studies designed to investigate the relationship between the level of zinc pyrithione (ZnPTO) deposited onto the scalp and the resultant scalp condition. A double-blind randomized vehicle-controlled clinical study comparing three shampoos - a vehicle, a low-depositing ZnPTO shampoo and a high-depositing ZnPTO shampoo - was carried out in the U.K. with 53 panelists with dandruff or mild-to-moderate seborrheic dermatitis of the scalp. Both shampoos containing ZnPTO were significantly superior in antidandruff efficacy to the vehicle. Furthermore, the high-depositing ZnPTO shampoo was significantly superior compared with the low-depositing ZnPTO shampoo in terms of both antidandruff efficacy and antimycotic activity. Antidandruff performance and antimycotic activity of ZnPTO-containing shampoos is highly dependent on the amount of active ingredient delivered to the scalp. Furthermore, careful manipulation of the formulation parameters of an antidandruff shampoo can result in enhanced levels of delivery of the active ingredient without having to increase the level of active ingredient within the formulation.

11.
Acta Clin Belg ; 55(3): 176-81, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10981327

RESUMO

Heparin-induced thrombocytopaenia is a dreaded, although infrequent, complication of heparin therapy. We report two cases of heparin-induced thrombocytopaenia (HIT) type II occurring in a patient treated with standard (unfractionated) heparin and in another patient given a low-weight molecular heparin. The clinical course of the first patient illustrates the potentially severe thrombotic complications of HIT. Both cases were treated successfully by danaparoid sodium. Clues to the diagnosis and treatment are briefly discussed.


Assuntos
Anticoagulantes/efeitos adversos , Antitrombina III/uso terapêutico , Sulfatos de Condroitina/uso terapêutico , Dermatan Sulfato/uso terapêutico , Heparina/efeitos adversos , Heparinoides/uso terapêutico , Heparitina Sulfato/uso terapêutico , Trombocitopenia/induzido quimicamente , Trombose/induzido quimicamente , Trombose Venosa/induzido quimicamente , Combinação de Medicamentos , Feminino , Heparina de Baixo Peso Molecular/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Trombocitopenia/tratamento farmacológico , Trombose/tratamento farmacológico , Trombose Venosa/tratamento farmacológico
12.
Nature ; 405(6782): 43-7, 2000 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-10811211

RESUMO

Bipolarity, the presence of a species in the high latitudes separated by a gap in distribution across the tropics, is a well-known pattern of global species distribution. But the question of whether bipolar species have evolved independently at the poles since the establishment of the cold-water provinces 16-8 million years ago, or if genes have been transferred across the tropics since that time, has not been addressed. Here we examine genetic variation in the small subunit ribosomal RNA gene of three bipolar planktonic foraminiferal morphospecies. We identify at least one identical genotype in all three morphospecies in both the Arctic and Antarctic subpolar provinces, indicating that trans-tropical gene flow must have occurred. Our genetic analysis also reveals that foraminiferal morphospecies can consist of a complex of genetic types. Such occurrences of genetically distinct populations within one morphospecies may affect the use of planktonic foraminifers as a palaeoceanographic proxy for climate change and necessitate a reassessment of the species concept for the group.


Assuntos
Evolução Molecular , Plâncton/genética , Animais , Regiões Antárticas , Regiões Árticas , Sequência de Bases , Clima Frio , DNA Ribossômico/genética , Genética Populacional , Genótipo , Dados de Sequência Molecular , Oceanos e Mares , Filogenia , Plâncton/classificação , RNA Ribossômico/genética
13.
J Infect ; 40(1): 92-4, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10762120

RESUMO

We report a case of Candida (Torulopsis) glabrata endophthalmitis which occurred 2 months following urological surgery. The patient was treated successfully with intravenous amphotericin B lipid complex (ABLC) and flucytosine. Diagnosis and management of this condition are discussed.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Endoftalmite/tratamento farmacológico , Fosfatidilcolinas/uso terapêutico , Fosfatidilgliceróis/uso terapêutico , Candida/isolamento & purificação , Candidíase/microbiologia , Combinação de Medicamentos , Endoftalmite/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
14.
Hawaii Med J ; 59(1): 15-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10740929

RESUMO

Practicing the Medical Home within communities is prefaced by university training through pediatric residency programs. Through collaboration experiences, future and practicing pediatricians can learn skills to form effective interprofessional relationships, thereby supporting families and children. Seeing parents as enabled partners and creating interdependent relationships with community members and professionals, enhances the medical home's broad base of support for families.


Assuntos
Serviços de Saúde Comunitária , Medicina Comunitária/educação , Internato e Residência , Pediatria/educação , Humanos , Relações Interprofissionais , Papel do Médico , Relações Médico-Paciente , Atenção Primária à Saúde , Avaliação de Programas e Projetos de Saúde , Qualidade da Assistência à Saúde , Programas de Autoavaliação , Inquéritos e Questionários
15.
J Food Prot ; 62(11): 1243-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10571311

RESUMO

The survival of Escherichia coli O157:H7 and of a nonpathogenic control strain of E. coli was monitored in raw ground beef that was stored at 2 degrees C for 4 weeks, -2 degrees C for 4 weeks, 15 degrees C for 4 h and then -2 degrees C for 4 weeks, and -20 degrees C. Irradiated ground beef was inoculated with one E. coli control strain or with a four-strain cocktail of E. coli O157:H7 (ca. 10(5) CFU/g), formed into patties (30 to 45 g), and stored at the appropriate temperature. The numbers of the E. coli control strain decreased by 1.4 log 10 CFU/g, and pathogen numbers declined 1.9 log 10 CFU/g when patties were stored for 4 weeks at 20 degrees C. When patties were stored at -2 degrees C for 4 weeks, the numbers of the E. coli control strain and the serotype O157:H7 strains decreased 2.8 and 1.5 log 10 CFU/g, respectively. Patties stored at 15 degrees C for 4 h prior to storage at -2 degrees C for 4 weeks resulted in 1.6 and 2.7 log 10-CFU/g reduction in the numbers of E. coli and E. coli O157:H7, respectively. Storage of retail ground beef at 15 degrees C for 4 h (tempering) did not result in increased numbers of colony forming units per gram, as determined with violet red bile, MRS lactobacilli, and plate-count agars. Frozen storage (-20 degrees C) of ground-beef patties that had been inoculated with a single strain of E. coli resulted in approximately a 1 to 2 log 10-CFU/g reduction in the numbers of the control strain and individual serotype O157:H7 strains after 1 year. There was no significant difference between the survival of the control strain and the O157:H7 strains, nor was there a difference between O157:H7 strains. These data demonstrate that tempering of ground-beef patties prior to low-temperature storage accelerated the decline in the numbers of E. coli O157:H7.


Assuntos
Escherichia coli O157/isolamento & purificação , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Produtos da Carne/microbiologia , Animais , Bovinos , Temperatura
16.
J Mol Evol ; 43(6): 672-7, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8995064

RESUMO

Phylogenetic analysis of five partial planktic foraminiferal small subunit (SSU) ribosomal (r) DNA sequences with representatives of a diverse range of eukaryote, archaebacterial, and eubacterial taxa has revealed that the evolutionary origin of the foraminiferal lineage precedes the rapid eukaryote diversification represented by the "crown" of the eukaryotic tree and probably represents one of the earliest splits among extant free-living aerobic eukaryotes. The foraminiferal rDNA sequences could be clearly separated from known symbionts, commensals, and food organisms. All five species formed a single monophyletic group distinguished from the "crown" group by unique foraminiferal specific insertions as well as considerable nucleotide distance in aligned regions.


Assuntos
Evolução Biológica , DNA Ribossômico/genética , Eucariotos/genética , Filogenia , Plâncton/fisiologia , Animais , Primers do DNA , DNA de Protozoário/genética , Diplomonadida/classificação , Diplomonadida/fisiologia , Eucariotos/classificação , Eucariotos/fisiologia , Células Eucarióticas , Kinetoplastida/classificação , Kinetoplastida/fisiologia , Modelos Biológicos , Plâncton/classificação , Reação em Cadeia da Polimerase/métodos , Homologia de Sequência do Ácido Nucleico
17.
S D J Med ; 49(9): 317-22, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8854751

RESUMO

The Aberdeen Area Indian Health Service, South Dakota Department of Health, and the Centers for Disease Control and Prevention have collaborated since 1985 to investigate hepatitis A in Indian communities in the Northern Plains and to implement clinical trials of hepatitis A vaccine. After licensure of the hepatitis A vaccine in February 1995, community wide immunization programs have been implemented effectively in several communities experiencing hepatitis A outbreaks. The state health department, tribal health departments, Indian Health Service facilities, Head Start programs and schools have provided hepatitis A immunizations to children aged 2-12 years in each of these communities after obtaining parental consent. Culturally-specific educational materials were developed and extensive health education efforts were provided by IHS and tribal programs. Hepatitis A contacts age 2-12 were offered the hepatitis A vaccine at the same time they were offered passive immunization with immune globulin. To date over 70% of parents contacted by letter or in person have returned consent forms to have their children immunized. Higher response rates were obtained in communities where home visits were made to explain this program in more detail. The outbreaks appear to have stopped after 70% or more of the children aged 2-12 years were immunized. Immunization programs are being implemented in all Northern Plains Indian communities utilizing hepatitis. A vaccine from the Vaccine For Children Program. These efforts will likely eliminate hepatitis A as a health problem for Indian communities.


Assuntos
Hepatite A/prevenção & controle , Programas de Imunização/normas , Esquemas de Imunização , Indígenas Norte-Americanos , Adolescente , Alaska , Algoritmos , Criança , Pré-Escolar , Hepatite A/terapia , Humanos , Guias de Prática Clínica como Assunto , South Dakota
18.
Eur J Neurosci ; 6(4): 657-67, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8025716

RESUMO

Melanin, or products directly associated with it, regulates the maturation of the neural retina because in hypopigmented mammals the central retina fails to develop fully. To determine whether this deficit is reflected in the distribution of photoreceptors, their topography has been studied in the retinae of normally reared pigmented and albino ferrets and animals reared under reduced light conditions. In both strains, the general distribution of rods and cones was similar to that in the cat, cone density peaking in the central retina and rod density peaking in an annulus around the area centralis. The cone population was organized in the form of an orderly mosaic whose regularity was measured at a wide range of retinal eccentricities. No differences were found in cone numbers or their mosaic distribution between pigmented and albino strains, either at the area centralis or at more peripheral regions. In both cases order within the cone mosaic was independent of density or retinal eccentricity. In the albinos there was a significant deficit in the number of rods at all retinal locations when compared with rod numbers in the pigmented animals. There were no differences between normally reared and dark-reared animals in this respect either within or between the strains. Therefore, the albino gene must have a selective and specific effect on the development of this cell type in the outer retina. Ganglion cells and rods are both affected by the albino gene, while cones are not. Because cones and ganglion cells are generated during the same period and rods are generated later, the albino gene cannot be acting during a particular developmental time window. Because the cone mosaic was normal in the albinos, in spite of a large rod deficit, the factors that regulate the spacing of cones cannot depend in any significant manner upon the later generation and subsequent addition of rods to the outer retina.


Assuntos
Melaninas/fisiologia , Células Fotorreceptoras/citologia , Retina/citologia , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Albinismo , Animais , Contagem de Células , Furões , Valores de Referência , Especificidade da Espécie
19.
Br J Surg ; 81(1): 124-6, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8313087

RESUMO

Despite the rapid growth of laparoscopic cholecystectomy, the comparative costs of this new procedure and open cholecystectomy remain unknown. In this study the costs have been evaluated of a consecutive series of patients undergoing these procedures in a district general hospital with an established resource management centre. Fifty consecutive patients undergoing open cholecystectomy between June 1988 and July 1990 immediately before the introduction of laparoscopic cholecystectomy and 100 patients undergoing laparoscopic cholecystectomy between August 1990 and June 1992 were studied. Costs estimated prospectively for each patient were compared. The mean cost per patient of open cholecystectomy was estimated at 2102 pounds compared with 2026 pounds for the first 50 patients undergoing the laparoscopic procedure. The mean cost (1744 pounds) for the second 50 patients undergoing laparoscopic cholecystectomy was less than that for either open cholecystectomy (P < 0.005) or the initial 50 laparoscopic operations (P < 0.03). Operating theatre costs and equipment costs were higher in both laparoscopic groups. These were offset by the higher nursing and ward costs of open cholecystectomy. For the laparoscopic procedure the operating theatre times and duration of hospital stay were both less in the second 50 patients than in the first 50. After the initial learning period, laparoscopic cholecystectomy is less expensive than the open operation and represents a cost-effective method for treatment of the patient with gallstones.


Assuntos
Colecistectomia/economia , Custos Hospitalares , Adulto , Idoso , Colecistectomia Laparoscópica/economia , Colelitíase/economia , Colelitíase/cirurgia , Feminino , Hospitais de Distrito/economia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escócia
20.
J Med Entomol ; 30(3): 561-70, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8099624

RESUMO

Observations based on time-lapse video recordings were used to study behavior associated with egg cannibalism in fourth-instar Toxorhynchites amboinensis (Doleschall) and Tx. r. rutilus (Coquillett). Analysis indicated that, once triggered by finding of the first egg, larvae of both species engaged in a systematic search of the water surface in an attempt to find additional eggs, which were often seized and eaten. Seven behavioral elements were identified in the search repertoire, and their relationships studied by analysis of a matrix of preceding and succeeding behaviors. The pivotal behavior was "sweep-adjust," which accounted for 87.2% of the time budget in Tx. amboinensis and 73.3% in Tx. r. rutilus. Activity in sweep-adjust consisted predominantly of side-to-side sweeps of the head, held just below the surface, punctuated by small forward adjustments of position. Quantitative aspects of the sweep arcs, in terms of angular and linear velocity, were determined for the two species. Eggs encountered during search probably were detected by mechanoreception, only within a very limited, kidney-shaped zone (area approximately 9.8 mm2) centered at the anterior margin of the head. Eggs were seized with the lateral palatal brushes but without head extension as seen in strikes at subsurface prey.


Assuntos
Canibalismo , Culicidae/fisiologia , Ovos , Animais , Comportamento Alimentar , Larva/fisiologia
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