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1.
The talar beak is a well-described secondary sign of talocalcaneal coalition but is not pathognomonic of the condition and may be seen in other causes of restricted or abnormal subtalar motion. We present an unusual complication of talar beaks in two patients who sustained fractures through their beaks. One of the patients described did not have a talocalcaneal coalition but had developed a beak following a compound fracture dislocation of the ankle joint complicated by infection, a previously undescribed predisposing cause.  相似文献   
2.

Background  

A sizeable number of HIV-infected patients receiving HAART do not maintain prolonged virologic suppression. We evaluated long-term HIV viral load (VL) responses to HAART as a risk factor for AIDS events (AE) that is independent of CD4 responses.  相似文献   
3.
Peripheral primitive neuroectodermal tumors (pPNETs) are aggressive, poorly differentiated neoplasms that occur in children and young adults. These tumors are associated with a peak incidence in the second decade and a slight male preponderance. Recently, Ewing sarcoma and pPNET tumors have been proven to carry identical translocations, the most common being t(11;22)(q24;q12). Intracranial Ewing sarcoma/pPNETs have rarely been described in the literature. We studied a case of intracranial pPNET arising in the right cavernous sinus of a 46-year-old man. On imaging, the tumor had both sellar and suprasellar components and was centered within the right parasellar region. Histologically, the tumor was composed of intermediate to large cells with round to oval hyperchromatic nuclei with distinct nucleoli. The cells contained a moderate amount of slightly basophilic cytoplasm. The tumor was markedly fibrotic and had collagen bands surrounding both individual and groups of cells. A large immunohistochemical panel was positive only for CD99 and vimentin. Fluorescence in situ hybridization did not show translocations associated with Ewing sarcoma/pPNET. However, a small percentage of these tumors can be negative for this translocation. In these cases, histology and immunohistochemical techniques in the absence of an alternative diagnosis are the only tools available to establish the diagnosis.  相似文献   
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5.
The use of primates for examining the effects of electromagnetic radiation on behavioural patterns is well established. Rats have also been used for this purpose. However, the monkey is of greater interest as its physiological make-up is somewhat closer to that of the human. Since the behavioural effects are likely to occur at lower field strengths for resonant absorption conditions for the head and neck, the need for determination of resonance frequencies for this region is obvious. Numerical techniques are ideal for the prediction of coupling to each of the organs, and accurate anatomically based models can be used to pinpoint the conditions for maximum absorption in the head in order to focus the experiments. In this paper we use two models, one of a human male and the other of a rhesus monkey, and find the mass-averaged power absorption spectra for both. The frequencies at which highest absorption (i.e. resonance) occurs in both the whole body and the head and neck region are determined. The results from these two models are compared for both E-polarization and k-polarization, and are shown to obey basic electromagnetic scaling principles.  相似文献   
6.
A literature search was conducted to report all cases of documented transmission of infectious diseases from donors to recipients of corneal transplants. Fourteen such cases have been reported. There is no experimental or clinical evidence to suggest the transmissions of either hepatitis or syphilis via corneal grafting. Available evidence regarding a number of neurologic and other disorders in which a slow virus etiology has been implicated were reviewed. On the basis of this review, we are able to draw certain conclusions and guidelines for selection or rejection of donor material for transplant surgery.  相似文献   
7.
Ten years of experience with falls from a height in children   总被引:2,自引:0,他引:2  
Falls from a height are a major cause of accidental death in urban children. The medical and social data on 61 children admitted over the last decade for falls of one or more stories were reviewed. Seventy-seven percent of the children survived. Of the children who fell three stories or less, all survived (100%). Fifty percent mortality occurred between the fifth and sixth floors. Seventy-seven percent of the falls were accidental and 23% of the children jumped or were pushed. The 96% decrease in accidental falls from windows since 1979 demonstrates that the "Children Can't Fly" program in New York City has almost eliminated accidental falls from windows in our hospital population.  相似文献   
8.
In 6 hemodialysis patients, enriching the "base concentrate" of a bicarbonate-containing dialysate-generating system with phosphorus succeeded in raising plasma phosphorus levels.  相似文献   
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10.
OBJECTIVE: This study aims to establish normal values for nucleated red blood cells in term singletons and factors associated with their elevation.STUDY DESIGN: Cord blood was prospectively collected from term singleton gestations from Feb. 1 to July 31, 1995. Umbilical vein white blood cells and nucleated red blood cells were counted and umbilical arterial pH was determined. Medical records provided maternal and neonatal information.RESULTS: Cord blood from 1112 cases was obtained and evaluated for nucleated red blood cells per 100 white blood cells. Nine outliers were censored (nucleated red blood cells per 100 white blood cells = 126 to 830); five cases were excluded because of missing data. The mean value of nucleated red blood cells per 100 white blood cells was 8.55, the SD was 10.27, and the range was 0 to 89. The value did not vary by maternal tobacco or drug use, anemia, fetal presentation, or mode of delivery. Both maternal diabetes and meconium were associated with elevated values, p < 0.01. Apgar scores and cord pHs showed trends toward inverse proportionality to the number of nucleated red blood cells per 100 white blood cells.CONCLUSION: The mean number of nucleated red blood cells per 100 white blood cells was 8.55, with a wide range and SD. Elevated values may be associated with markers of intrauterine hypoxia such as meconium, lower Apgar scores, and lower pH values. (Am J Obstet Gynecol 1997;176:1149-56.)  相似文献   
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