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1.
This is a prospective, non-randomized study to evaluate and compare the results, morbidity and surgical time for endonasal carbon-dioxide laser assisted dacryocystorhinostomy and external dacryocystorhinostomy. 70 consecutive patients of chronic dacryocystitis with nasolacrimal duct obstruction were selected for the study. 36 patients under went endonasal CO2 laser assisted dacryocystorhinostomy and 34 had external dacryocystorhinostomy. Selection of the type of operation was left to the patient's choice. All the patients had preoperative counseling and both the procedures were explained in detail with their advantages and disadvantages. Patients not willing for the external incision were selected for endonasal laser assisted dacryocystorhinostomy and others were operated via external approach. Silicone tubes were put in all the patients for three months after surgery. The final follow up was 12 months after the removal of silicone tubes. The patency of the lacrimal passage was confirmed by irrigation, and patients were questioned about their symptoms. The success rates, 12 months after removal of silicone tubes were 100% in endonasal CO2 laser assisted dacryocystorhinostomy and 88.24% in external dacryocystorhinostomy. The surgical time of endonasal laser assisted dacryocystorhinostomy was 38 minutes as compared to 62 in external dacryocystorhinostomy. Complication rate in both groups was almost equal. Thus, we came to the conclusion that Endonasal CO2 laser assisted dacryocystorhinostomy is a better surgical option to external dacryocystorhinostomy in cases of chronic dacryocystitis with nasolacrimal duct obstruction, with shorter surgical time.  相似文献   
2.
From the data submitted to the Pan American Health Organization (PAHO) by nationwide programs against sexually transmitted diseases (STD), HIV infection, and AIDS (2002), one can estimate the overall prevalence of syphilis among pregnant women to be 3.1% and to range from 1.00% in Peru to 6.21% in Paraguay. According to these data, the incidence of congenital syphilis ranges from 1.4 per 1000 live births in El Salvador to 12.0 per 1000 live births in Honduras. Among men who engage in sex with other men, who often classify themselves as heterosexual, as well as in female sex workers, the prevalence of syphilis ranged from 5% to 15%. Factors that determine the persistence of congenital syphilis as public health problem include a lack of awareness of the seriousness of the problem among politicians, health officials, and health care providers, difficult access to prenatal care, and screening services, a low demand for the test among users, and the stigma and discrimination that surround sexually transmitted diseases (STD). This paper seeks to focus the attention of health professionals on maternal and congenital syphilis so they will undertake actions, using an interprogrammatic approach, to eliminate congenital syphilis from Latin America and the Caribbean. Eliminating congenital syphilis will only become possible if interventions targeting vulnerable groups are also implemented. PAHO's role in eliminating congenital syphilis includes determining the baseline situation in the Region as a whole and in each country, developing communication and procurement strategies, supporting nationwide programs, promoting operational research, and facilitating interprogrammatic coordination.  相似文献   
3.
4.
An Alternative Surgical Technique in Orthotopic Cardiac Transplantation   总被引:8,自引:0,他引:8  
A bstract Forty patients underwent orthotopic cardiac transplantation at Wythenshawe Hospital between May 1991 and November 1992. Twenty patients had transplantation using an alternative technique that preserves the shape of the left atrium and leaves the right atrium intact (group A). The remaining twenty had conventional transplantation using the technique described by Lower and Shumway (group B). The patients were randomized to either the new or the conventional technique on an alternate basis. There was no mortality in group A, but two patients in group B developed right ventricular failure and died. Two patients in each group developed nodal rhythm and all four recovered sinus rhythm. Echocardiography and Doppler velocimetry at the transvalvular level confirmed normal atrial function in group A with erratic atrial contraction wave in group B. There was also slightly lower incidence of mitral and tricuspid valve regurgitation in group A than in group B. The improved atrial function in group A may play a part in the prevention of right sided failure following cardiac transplantation.  相似文献   
5.
Array-based copy number analysis has recently emerged as a rapid means of mapping complex and/or subtle chromosomal abnormalities. We have compared two such techniques, using bacterial artificial chromosome (BAC) and single nucleotide polymorphism (SNP) arrays in the evaluation of a 45-year-old woman with dysmorphic features, mental retardation, psychosis, and an unbalanced derivative chromosome 18, (46,XX, der(18)t(18;?)(p12;?)). Both array-based methods demonstrated that the additional material on chromosome 18 was of 5p origin. The 5p duplication mapped telomeric to 25.320 Mb (BAC array) and 25.607 Mb (SNP array), corresponding to the band 5p14.1. Both BAC and SNP arrays also showed a deletion involving chromosome 18p extending telomeric from 8.437 Mb (BAC array) and 8.352 Mb (SNP array), corresponding to the band 18p11.23. Molecular cytogenetic mapping using fluorescence in situ hybridization (FISH) supported the array findings and further refined the breakpoint regions, confirming that the BAC and SNP chips were both useful in this regard. Both case reports and linkage analyses have implicated these chromosomal intervals in psychosis. The array-based experiments were completed over the course of several days. While these methods do not eliminate the requirement for traditional fine-mapping, they provide an efficient approach to identifying the origin and extent of deleted and duplicated material in chromosomal rearrangements.  相似文献   
6.
Summary Diverting activity is defined as any physical or mental activity performed between or simultaneously with bouts of exhaustive, local muscular work. In the present experiments bouts of exhaustive work consisting of rhythmic lifting of weights were performed with the elbow flexors or with the flexors of the middle finger. Pauses of 2 min duration spent in complete rest or while performing diverting activities alternated between the bouts of work. As diverting activities were used: Physical activity, dynamic or static, performed with big or small muscle groups (other than the fatigued group), or mental activity (problem solving). It was found that the amount of work that could be performed after a pause with diverting activity was always larger than the amount of work performed after a passive pause. The beneficial effect was seen also when the blood flow to the exhausted muscles was interrupted by pneumatic cuffs. Determination of the blood flow in the exhausted muscles by means of Xe-133 clearance showed no systematic blood flow increases caused by the diverting activity. It is concluded that recuperation after local muscle fatigue is influenced by a central nervous factor (Setchenov phenomenon) that is largely independent of the local blood flow.  相似文献   
7.
We report two unrelated patients each with two supernumerary marker chromosomes (SMCs) derived from chromosome 15, and thus resulting in partial hexasomy. Hexasomy in the one case (family 1) was diagnosed at prenatal diagnosis and did not include the Prader-Willi/Angelman critical region (PWACR). The double SMCs were also found in the mother, the pregnancy continued to term, and an apparently phenotypically normal child was born. This represents the first report of transmission of double SMCs from mother to child. In the second case (family 2), the hexasomy did include the PWACR and was de novo in origin. This patient manifested severe psychomotor retardation, clefting of the soft palate, hypotonia, seizure-like episodes, and other phenotypic features. The aberrant phenotype is attributable to the hexasomy for the PWACR gene loci. The normal homologs of chromosome 15 proved to be biparental in origin while the two SMCs appeared maternal.  相似文献   
8.

Essentials

  • Strong P2Y12 blockade may cause platelet inhibition that is only minimally enhanced by aspirin.
  • We evaluated aspirin withdrawal on platelet reactivity in ticagrelor treated patients.
  • Aspirin withdrawal resulted in increased platelet reactivity to arachidonic acid.
  • Aspirin withdrawal caused little difference in adenosine diphosphate‐induced platelet aggregation.

Summary

Background

Recent studies have shown that the thromboxane A2‐dependent pathway is dependent on the ADP–P2Y12 pathway, and that strong P2Y12 receptor blockade alone causes inhibition of platelet aggregation that is minimally enhanced by aspirin. Data from the PLATO trial suggested that, among ticagrelor‐treated patients, high‐dose versus low‐dose (< 100 mg day?1) aspirin is associated with an increased risk fof ischemic events.

Objectives

To evaluate the impact of aspirin withdrawal on platelet reactivity in acute coronary syndrome (ACS) patients treated with a potent P2Y12 blocker.

Patients/Methods

This was a current prospective, randomized, placebo‐controlled, double‐blind, cross‐over study. The study population comprised 22 consecutive ACS patients who underwent percutaneous coronary intervention and were treated with aspirin (100 mg day?1) and ticagrelor. Thirty days post‐ACS, open‐label aspirin was stopped, and patients were randomized to either blinded aspirin or placebo for 2 weeks, with each patient crossing over to the other arm for an additional 2 weeks. Platelet reactivity to arachidonic acid and ADP determined with light‐transmission aggregometry (LTA) and VerifyNow was evaluated at baseline, and 2 weeks and 4 weeks later.

Results

Aspirin withdrawal resulted in an increase in arachidonic‐acid induced platelet reactivity as determined with both LTA (77.0% ± 11.3% versus 20.8% ± 4.4%) and VerifyNow (607.7 ± 10.6 aspirin reaction units [ARU] versus 408.5 ± 14.4 ARU). Platelet response to ADP, as determined with both LTA and VerifyNow, did not differ with either aspirin or placebo (32.9% ± 2.6% versus 35.8% ± 3.6%, and 33.5 ± 6.4 P2Y12 reaction units (PRU) versus 29.6 ± 5.7 PRU, respectively).

Conclusions

Aspirin withdrawal early post‐ACS results in increased platelet reactivity in response to arachidonic acid, despite concomitant treatment with the potent P2Y12 blocker ticagrelor.
  相似文献   
9.
BackgroundPlatelet function testing (PFT) in patients treated with P2Y12 inhibitors has been widely evaluated for the prediction of stent thrombosis, myocardial infarction, and bleeding events following percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS). Thus, PFT-guided treatment could positively affect patient outcomes. Data regarding clinical parameters for predicting platelet reactivity in ACS patients are limited. Therefore, our study aims to evaluate CHADS2 and CHA2DS2-VASc scores as predictors for platelet reactivity in ACS patients.MethodsTwo hundred and ninety-one consecutive patients who underwent PCI and were treated with aspirin and clopidogrel due to ACS were tested for their CHADS2, CHA2DS2-VASc scores and platelet reactivity using adenosine diphosphate (ADP)-induced aggregation (conventional aggregometry). Patients were classified into groups according to their CHADS2 and CHA2DS2-VASc scores. Low-risk group (0–1 score) for CHADS2 and CHA2DS2-VASc scores and high-risk group (2–6, 2–9) for CHADS2 and CHA2DS2-VASc scores, respectively. Furthermore, platelet reactivity in each group were compared (low CHADS2 group vs high CHADS2 group, and low CHA2DS2-VASc vs high CHA2DS2-VASc). Platelet reactivity was defined as low platelet reactivity (<19 U), optimal platelet reactivity [(OPR); 19–46 U], and high on-treatment platelet reactivity [(HPR); >46 U]. Thereafter receiver operating characteristic curve analysis was conducted to verify whether CHADS2 and CHA2DS2-VASc scores could predict platelet reactivity.ResultsLow CHADS2 and CHA2DS2-VASc scores were significantly correlated with lower mean platelet ADP-induced aggregation as compared with high CHADS2 and CHA2DS2-VASc scores [45.5 U (± 16) vs. 54.8 U (±15) and 44.2 U (±16) vs. 51.0 U (±17), respectively, p = 0.01 for both].ConclusionIn ACS patients treated with clopidogrel following PCI, high CHADS2 and CHA2DS2-VASc scores correlated with HPR and lower scores correlated with OPR. Further studies are needed to evaluate our findings’ clinical implications.  相似文献   
10.

Objectives:

To evaluate the knowledge and behavior of workers at a Saudi airport regarding public health emergency measures applied during Hajj season.

Methods:

This study is a cross-sectional study conducted at the Prince Mohammed International Airport in Al-Madinah Al-Munawwarah, Saudi Arabia between August and September 2014. Data were collected by semi-structured questionnaires during personal interviews. Non-random purposive sampling was conducted to target workers at higher risk of acquiring infection from travellers.

Results:

One hundred and eighty-six participants were recruited of whom 92.5% were males. The study participants were workers in 8 different sectors. Twenty-six percent of the participants were health workers. Non-health workers were more likely to be concerned on acquiring infection while working at the airport compared with health workers (p=0.023). The most commonly feared disease was Ebola viral disease (EBV) among 30% of health workers, and 47% of non-health workers. Approximately 47% of non-health workers reported no knowledge of the procedures implemented during public health emergencies. The proportion of participants who received public health related training among non-health workers was significantly lower compared with health workers (p<0.00001).

Conclusion:

More emphasis should be given to educating airport workers on the potential health threats at the airport. Specific guidelines for public health emergencies at the airport should be established and communicated with airport sectors.Airports are frontier gates where proper public health measures are likely to reduce the possibility of allowing the entrance of communicable disease to a country. According to the World Health Organization (WHO) International Health Regulations mandate WHO member states to ensure that every designated point of entry is equipped with staff and instruments enabling smooth movements of the travellers while maintaining appropriate public health measures.1 Maintaining such regulations is likely to enhance proper travellers’ movement during public health emergencies by reducing possible interference between application of preventive public health measures, and the ability of travellers to access the designated points of entry. Additionally, ensuring the application of public health measures might aid in preventing the occurrence of any public health emergencies. A public health emergency is defined as any situation with health consequences that are likely to overwhelm the community’s routine capability of addressing them. A health situation can be considered as an emergency if there is a risk due to timing, such as facing emerging diseases threats during Hajj season, scale, as with an overwhelming number of causalities, or due to the unpredictability of the situation. Defining the nature of potential public health emergencies is crucial to allow competent development of preparedness plans.2 Having a large number of passengers arriving at a particular point of entry during a limited time is a burden on the available health services. A meticulous state of readiness is required to respond to any risk of spreading a communicable disease. The state of readiness is maintained by several steps including preparation of staff, equipment, and buildings.3,4 The burden of not maintaining effective public health event response measures is aggravated if an epidemic is announced in a particular region of the globe where travellers form these areas are scheduled to arrive in the country. During the Hajj season of 2014, the Ebola Virus Disease (EVD), which is a viral hemorrhagic disease, was announced as an epidemic disease in Guinea, Liberia, and Sierra Leone in West Africa. Additionally, a localized spread of the virus was announced in certain areas of Nigeria.5 The Saudi Arabian government, as a preventive measure, decided to prevent citizens of EVD-affected countries from entering the country. However, nationals of Nigeria were exempt as no extended transmission of EVD was announced.6,7 Nonetheless, several procedures were applied to prevent the transmission of Ebola virus among thousands of Nigerian pilgrims arriving in the country. These measures were mainly related to exit screening of travellers in Nigeria,8 and entry screening at points of entry in Saudi Arabia. Additionally, the Ministry of Health in Saudi Arabia produced response plans for infectious diseases (Middle East Respiratory Syndrome [MERS] and EVD) to be implemented during Hajj.9 There are many potential sources of infectious disease transmission from a single infected individual. The presence of infected travellers, such as an EVD infection, on an aircraft increases the risk of transmitting infection to neighboring passengers and flight crew. Airport workers, such as ground workers handling cleaning of aircrafts and lavatories, are at risk of the infection, especially with the presence of spilled infectious materials. Airport workers handling the flow of passengers during busy times are at risk of acquiring infection such as immigration, customs, security, and healthcare workers. Therefore, all of these individuals have to be aware of the potential health threats at the airport, should be aware of preventive methods, how to use preventive methods, and know what to do when facing a public health emergency event in the airport. Prince Mohammed Airport (Al-Madinah, Saudi Arabia) workers’ level of knowledge of the potential health threat at the airport is currently not known. Additionally, the attitude and practice of the staff when a public health emergency is announced in the airport is not measured. The significance of this study stems from the ability to investigate the degree to which airport workers, at the time of dealing with travellers during Hajj season, were able to deal with potential urgent infectious cases, and to adhere to the relevant protective guidelines.  相似文献   
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