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1.

Objective

To systematically review literature on uptake and timeliness of diphtheria-tetanus-pertussis, measles-mumps-rubella, and/or polio-containing vaccines in infants who were born preterm, with a low birth weight, and/or with chronic health conditions that were diagnosed within the first 6?months of life.

Methods

Using a standardized search strategy developed by a medical librarian, records were extracted from MEDLINE, Embase, Database of Abstracts of Reviews of Effects, and CINAHL up to May 8, 2018.

Results

Out of the 1997 records that were screened, we identified 21 studies that met inclusion criteria. Eleven studies assessed vaccine coverage and/or timeliness in preterm infants, 6 in low birth weight infants, and 7 in children with chronic health conditions. Estimates of coverage in these populations were highly variable, ranging from 40% to 100% across the vaccines and population groups.

Conclusions

There is a lack of studies reporting coverage and timeliness of routine immunizations in special populations of children.

Policy implications

Our review suggests a need for improved surveillance of immunization status in special populations of infants, as well as a need for standardization of reporting practices.  相似文献   
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Background. A persistent patent ductus arteriosus (PDA) may delay closure of a coexisting atrial septal defect (ASD) due to volume loading and enlargement of the left atrium. The purpose of this study was to investigate the natural history of ASD size in patients with a PDA following transcatheter PDA occlusion. Methods. All patients with an ASD and a PDA who underwent transcatheter PDA occlusion at Texas Children’s Hospital were identified. Patients with ASD diameter <3 mm, or additional cardiac defects were excluded. Eight patients (7 females) with small‐ to moderate‐sized ASDs and a PDA were identified. Patient demographics, echocardiographic data, and cardiac catheterization data were recorded. Data were analyzed by 1‐tailed t‐test. Results. Following PDA occlusion, ASD diameter decreased in 6 of 8 patients by a mean of 3.8 mm (±2.3 mm), including 2 that closed. The median duration of follow‐up was 689 days. One ASD remained unchanged and 1 increased in size. The mean maximum ASD diameter decreased from 6.4 mm (±2.2 mm) to 3.9 mm (±3.4 mm) (P = .03). Two patients underwent subsequent transcatheter ASD occlusion. Conclusion. Following transcatheter PDA occlusion, small‐ to moderate‐sized ASDs have significant probability to decrease in size, and possibly close. In infants and children, we recommend transcatheter PDA occlusion, and serial follow‐up of the size of the ASD. This will allow many small‐ to moderate‐sized ASDs to either close, or become smaller, obviating the need for future intervention.  相似文献   
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A 66‐year‐old woman developed firm, painless, slowly growing nodular masses over her elbows, fingers, toes, and left hip over four years. Aspiration of the elbow mass revealed a white chalky material that was shown to be carbonate apatite on infrared spectroscopy and energy dispersive X‐ray spectroscopy. We discuss the classification of tumoral calcinosis and the nature of the calcium deposits. Tumoral calcinosis should be differentiated from tophaceous gout and calcium pyrophosphate dihydrate crystal deposition disease. Polarizing light microscopy and crystal analysis by X‐ray and infrared spectroscopy, electron or X‐ray diffraction will confirm the diagnosis. Secondary causes of tumoral calcinosis should also be excluded.  相似文献   
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Using recent data from the U.S., the argument is reiterated that sexually transmitted diseases (STDs) have serious consequences on female morbidity, mortality, pregnancy outcome and that the cost of screening and treatment can afford significant savings. Since the rosy view of the 1950s that STDs had been eliminated with penicillin, new viral, parasitic and bacterial forms have emerged, and antibiotic-resistant classical STDs have increased yearly. 13 million new cases were reported in 1989, excluding non-reportable diseases and asymptomatic infections, such as over half of chlamydia cases. Mortality is possible from STDs, most notably from AIDS, now among the top 5 causes of death of women aged 15-44. Other fatal outcomes are cervical cancer related to human papilloma virus, accelerated by HIV, pelvic inflammatory diseases (PID) its consequences, ectopic pregnancy. Symptomatic PID affects 1 million women, resulting in 210,000 hospitalizations per year. Ectopic pregnancy accounts for 12% of maternal mortality. STDs are involved in neonatal infections with HIV, syphilis, gonorrhea, chlamydia, cytomegalovirus, and herpes. Chorioamnionitis, a finding in many miscarriages, is caused by many of the same organisms. Several studies have projected sizeable potential savings, even within the current year, by providing STD screening and treatment in family planning clinics and prenatal care, in terms of prevention of hospitalization of women, and intensive care for low birth weight, premature and infected newborns.  相似文献   
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Background. The “elephant trunk” technique, using a free-floating vascular prosthesis, was originally described to facilitate a subsequent operation on the downstream aorta. We developed an additional refinement of this technique, called the “bidirectional elephant trunk.” This option may represent an interesting tool in more complex aortic operations, especially when the descending aorta has to be replaced first in patients with concomitant pathology of the ascending aorta or of the aortic arch.

Methods. The initial operation is performed through a left thoracotomy. The proximal elephant trunk is created by invaginating the future aortic arch graft into the descending aortic graft. The proximal anastomosis between the doubled graft and the proximal descending aorta is performed first. During construction of the distal anastomosis, a distal elephant trunk may be inserted likewise. If the aortic arch and ascending aorta have to be replaced later, this second step is performed through a median sternotomy. The free-floating arch graft is pulled out of the proximal descending aorta with a nerve hook, unfolded, and used for total arch replacement.

Results. This technique was used successfully in 3 patients without mortality. No major complications were observed excepted persistent hoarseness in a patient with preoperative paresis of the recurrent nerve. No perfusion problems due to the unfolding of the free-floating graft occurred during the second operation.

Conclusions. The bidirectional elephant trunk technique is an interesting option that may be suitable for patients presenting with a complex pathology of the whole thoracic aorta when the descending segment has to be replaced first.  相似文献   

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BACKGROUND. Unsuccessful vascular repair may further preexisting limb ischemia and thus increase the risk of revascularization procedures. METHODS. The results of 94 primary major amputations (group A) have been analyzed and compared with 112 secondary ablations (group B) carried out after failed revascularization efforts. All patients suffered from chronic critical ischemia (grades III and IV) of the lower extremities. In group A the severity of ischemic symptoms was more pronounced (trophic changes in 80% vs 66% in group B), and a preponderance for older age, diabetes mellitus, and incidence of cardiac failure and cerebrovascular insufficiency was evident. RESULTS. In patients undergoing secondary amputation the final transection level was adversely affected by preceding unsuccessful reconstructive attempts. In spite of the better risk profile, 30% of patients in group B were subjected to above-knee amputation compared with 13% of patients in group A. The aggravated limb ischemia caused by graft failure is reflected by the decrease of the mean ankle systolic pressure index from 0.27 to 0.13 (before and after failed revascularization attempts). Although more amputations at the below-knee level were performed initially in group A, primary wound healing was obtained among these subjects in 68% of patients (compared with only 39% for patients in group B). CONCLUSIONS. In a substantial number of cases preexisting limb ischemia may be promoted by failed attempts at vascular reconstruction, thus leading to severe wound healing complications and a higher level of amputation.  相似文献   
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