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31.
This study evaluated the temperature rise on external root surfaces by simulating the removal of metallic posts by applying ultrasound, with or without refrigeration and at different times. The crowns of 30 healthy maxillary central incisors were removed and the roots were treated endodontically. The prosthetic spaces were prepared and impressions were taken with self-curing acrylic resin. After casting with a copper-aluminum alloy, the posts were blasted with aluminum oxide and cemented with resin cement. The specimens were randomly assigned to three groups according to the time of ultrasonic vibration (30, 60, or 120 seconds) and were subdivided into two groups, those cooled with and without water refrigeration. A thermocouple connected to a digital thermometer was positioned on the root external surface and the maximum temperature was recorded. Data were submitted to ANOVA and Tukey's test. Analysis of the results revealed statistical difference among groups (p < 0.01). Ultrasound (with and without water spray) increased root temperature significantly, reaching values of more than 50 degrees C. The exception was the group that used 30 seconds of ultrasound with refrigeration; root temperature reached 35.4 degrees C, making it the only tested condition that remained below the critical value (50 degrees C).  相似文献   
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33.

Background

Primary eye care (PEC) in sub-Saharan Africa usually means the diagnosis, treatment, and referral of eye conditions at the most basic level of the health system by primary health care workers (PHCWs), who receive minimal training in eye care as part of their curricula. We undertook this study with the aim to evaluate basic PEC knowledge and ophthalmologic skills of PHCWs, as well as the factors associated with these in selected districts in Kenya, Malawi, and Tanzania.

Methods

A standardized (26 items) questionnaire was administered to PHCWs in all primary health care (PHC) facilities of 2 districts in each country. Demographic information was collected and an examination aimed to measure competency in 5 key areas (recognition and management of advanced cataract, conjunctivitis, presbyopia, and severe trauma plus demonstrated ability to measure visual acuity) was administered.

Results

Three-hundred-forty-three PHCWs were enrolled (100, 107, and 136 in Tanzania, Kenya, and Malawi, respectively). The competency scores of PHCW varied by area, with 55.7%, 61.2%, 31.2%, and 66.1% scoring at the competency level in advanced cataract, conjunctivitis, presbyopia, and trauma, respectively. Only 8.2% could measure visual acuity. Combining all scores, only 9 (2.6%) demonstrated competence in all areas.

Conclusion

The current skills of health workers in PEC are low, with a large per cent below the basic competency level. There is an urgent need to reconsider the expectations of PEC and the content of training.
  相似文献   
34.

Background

This project examined the surgical productivity and attrition of non-physician cataract surgeons (NPCSs) in Tanzania, Malawi, and Kenya.

Methods

Baseline (2008-9) data on training, support, and productivity (annual cataract surgery rate) were collected from officially trained NPCSs using mailed questionnaires followed by telephone interviews. Telephone interviews were used to collect follow-up data annually on productivity and semi-annually on attrition. A detailed telephone interview was conducted if a surgeon left his/her post. Data were entered into and analysed using STATA.

Results

Among the 135 NPCSs, 129 were enrolled in the study (Kenya 88, Tanzania 38, and Malawi 3) mean age 42 years; average time since completing training 6.6 years. Employment was in District 44%, Regional 24% or mission/ private 32% hospitals. Small incision cataract surgery was practiced by 38% of the NPCSs. The mean cataract surgery rate was 188/year, median 76 (range 0-1700). For 39 (31%) NPCSs their surgical rate was more than 200/year. Approximately 22% in Kenya and 25% in Tanzania had years where the cataract surgical rate was zero. About 11% of the surgeons had no support staff.Factors significantly associated with increased productivity were: 1) located at a regional or private/mission hospital compared to a district hospital (OR = 8.26; 95 % CI 2.89 – 23.81); 2) 3 or more nurses in the eye unit (OR = 8.69; 95% CI 3.27-23.15); 3) 3 or more cataract surgical sets (OR = 3.26; 95% CI 1.48-7.16); 4) a separate eye theatre (OR = 5.41; 95% CI 2.15-13.65); 5) a surgical outreach program (OR = 4.44; 95% CI 1.88-10.52); and 6) providing transport for patients to hospital (OR = 6.39; 95% CI 2.62-15.59). The associations were similar for baseline and follow-up assessments. Attrition during the 3 years occurred in 13 surgeons (10.3%) and was due to retirement or promotion to administration.

Conclusions

High quality training is necessary but not sufficient to result in cataract surgical activity that meets population needs and maintains surgical skill. Needed are supporting institutions and staff, functioning equipment and programs to recruit and transport patients.
  相似文献   
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36.
Cocaine is the most commonly used illicit drug among patients presenting at hospital emergency departments and the most frequent cause of drug-related deaths reported by medical examiners. Various respiratory problems temporally associated with cocaine use have been reported. Acute and chronic uses also are responsible for lung complications, such as pulmonary edema, alveolar hemorrhage, pulmonary hypertension, organizing pneumonia, emphysema, barotrauma, infection, cancer, eosinophilic disease, and aspiration pneumonia. Although most imaging findings are nonspecific, they may raise suspicion of a cocaine-related etiology when considered together with patients’ profiles and medical histories. This literature review describes cocaine-induced diseases with pulmonary involvement, with an emphasis on high-resolution chest computed tomographic findings and patterns.  相似文献   
37.
38.

OBJECTIVES:

To evaluate the performance of fine and cutting needles in computed tomography guided-biopsy of lung lesions suspicious for malignancy and to determine which technique is the best option for a specific diagnosis.

METHODS:

This retrospective study reviewed the data from 362 (71.6%) patients who underwent fine-needle aspiration biopsy and from 97 (19.7%) patients who underwent cutting-needle biopsy between January 2006 and December 2011. The data concerning demographic and lesion characteristics, procedures, biopsy sample adequacy, specific diagnoses, and complications were collected. The success and complication rates of both biopsy techniques were calculated.

RESULTS:

Cutting-needle biopsy yielded significantly higher percentages of adequate biopsy samples and specific diagnoses than did fine-needle aspiration biopsy (p<0.05). The sensitivity, specificity, and accuracy of cutting-needle biopsy were 93.8%, 97.3%, and 95.2%, respectively; those of fine-needle aspiration biopsy were 82.6%, 81.3%, and 81.8%, respectively (all p<0.05). The incidence of pneumothorax was higher for fine-needle aspiration biopsy, and that of hematoma was higher for cutting-needle biopsy (both p<0.05).

CONCLUSIONS:

Our experience using these two techniques for computed tomography-guided percutaneous biopsy showed that cutting-needle biopsy yielded better results than did fine-needle aspiration biopsy and that there was no significant increase in complication rates to indicate the best option for specific diagnoses.  相似文献   
39.
Background. DNA ploidy analysis has been investigated as a prognostic indicator in prostate cancer. Most of the data is derived from retrospective studies using paraffin-embedded tissue. This method has drawbacks related to the quality of DNA histograms and uncontrolled data collection. Methods. DNA ploidy analysis of freshly resected prostatic tissue was prospectively compared with conventional prognostic variables in 97 men treated with radical prostatectomy for localized prostate cancer. Results. Regarding the patients, 31.9% were African American and 66% had pathologic Stages C or D1 disease. Only 9.6% of patients with Stages A2 and B had a prostate-specific antigen (PSA) value greater than 10 ng/ml, whereas 97% of patients with PSA values greater than 20 ng/ml had pathologic Stages C and D1. PSA levels correlated with Gleason score (P = < 0.05); 51% and 100% of patients with Gleason score 5–7 and 8–10, respectively, had PSA values greater than 10 ng/ml. Twenty-two patients (23%) had DNA aneuploid tumors. Comparisons of mechanical to enzymatic cell suspensions indicated that DNA aneuploidy was better preserved in mechanical cell preparations. DNA ploidy correlated with pathologic stage (P = < 0.05) and Gleason score (P = < 0.05). Fifteen of 79 patients (18.9%) with Gleason score 5–7 had DNA aneuploid tumors versus 71.4% of patients with Gleason score 8–10. PSA groups correlated with ploidy status (P = 0.01). Although the majority of patients (19 of 22) with DNA aneuploid tumors had elevated preoperative PSA levels, none had a PSA value greater than 50 ng/ml. Conclusions. DNA ploidy analysis correlated with established prognostic indicators in prostate cancer; however, its independent correlation with natural history and treatment outcome must be established for it to have an effect on therapeutic decisions.  相似文献   
40.
The potential use of amino acids by ruminal microorganisms converting them into microbial protein for ruminants makes it challenging to supplement these nutrients in an accessible form in animals’ diets. Several strategies to protect amino acids from ruminal degradation were reported, producing amino acids available for the protein used in the intestine called “bypass.” The intercalation of biomolecules in clay mineral minerals has gained notoriety due to its ability to support, protect, transport, physicochemical properties and non-toxicity. This study aimed to investigate the incorporation of L-lysine (Lys), L-methionine (Met), and L-tryptophan (Trp) amino acids in the clay minerals sepiolite (Sep) and Veegum® (Veg) using the adsorption method. The characterization techniques of X-ray diffraction and infrared spectroscopy indicated the presence of biomolecules in the inorganic matrices. Elemental and thermal analyzes monitored the percentages of incorporated amino acids. They showed better incorporation capacities for Veg, such as Met-Veg < Lys-Veg < Trp-Veg and Lys-Sep < Met-Sep < Trp-Sep for sepiolite, except for the incorporation of Met. Matrices provide a promising alternative for planning the administration of biomolecules, using essential amino acids as models, and may offer an alternative to improve functional diet strategies.  相似文献   
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