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31.
EEGs of 42 patients with herpes zoster and 6 with herpes zoster-associated encephalitis were studied to characterize the nature and prevalence of EEG abnormalities in apparently uncomplicated herpes zoster. Thirty-one percent of herpes zoster patients had EEG changes with reduced rhythm frequency ranging from 7 to 2 Hz activity. Frontotemporal localization was observed in 54% of the abnormal EEGs. When compared to EEG in herpes zoster associated encephalitis, the findings were qualitatively the same, but tended to be more severe in the encephalitis cases. No effect of acyclovir on the EEG could be demonstrated. 相似文献
32.
Radiotherapy has been successful in treating localized prostate cancer; however, a subset of patients will experience disease
recurrence. Determination of the recurrence location must be made using pretreatment and posttreatment clinical variables,
imaging, and postradiotherapy biopsy. Patients presumed to have local-only recurrence, optimal clinical risk factors, and
an extended life expectancy may be considered for salvage local treatment. Current options include salvage surgery, cryoablation,
and brachytherapy. Although they are associated with higher morbidity than primary therapy, salvage treatments can be effective
and can still provide patients with a good oncologic and functional outcome. As these modalities continue to improve and patient
selection is optimized, better results will evolve. 相似文献
33.
34.
Scott D Simon Erik P Castle Robert G Ferrigni Paul E Andrews 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(2):205-207
PURPOSE: To determine whether a routine postoperative chest x-ray is required following uneventful laparoscopic nephrectomy to rule out pneumothorax. METHODS: From June 1999 to May 2003, 308 laparoscopic nephrectomy cases were performed by 5 different surgeons. This consisted of 121 radical nephrectomies, 106 donor nephrectomies, 29 simple nephrectomies, 29 partial nephrectomies, and 23 nephroureterectomies. Of the 308 procedures, 186 postoperative chest x-ray s were obtained in the recovery room: 183 routinely and 3 for known intraoperative diaphragmatic injuries. Routine chest x-rays were not obtained in 122 cases due to the individual surgeon's preference. Of these 122 patients, 15 underwent chest x-ray performed while hospitalized secondary to pulmonary issues or fever. RESULTS: Of the 308 cases, 4 pneumothoraces were identified on chest x-ray. Three were identified in the patients who had intraoperative identification of diaphragmatic injury. The fourth pneumothorax was identified in a patient who did not have a routine postoperative chest x-ray but did have a chest x-ray obtained due to postoperative shoulder pain. The pneumothorax in this patient resolved spontaneously. No incidental findings existed of pneumothorax in any patient who underwent routine postoperative chest x-ray. CONCLUSION: In our series, a pneumothorax was identified either intraoperatively or based on postoperative clinical findings. None of the 183 routine postoperative chest x-rays changed patient management. Routine postoperative chest x-ray is not necessary in uncomplicated laparoscopic nephrectomy. 相似文献
35.
36.
In vivo detection of single cells by MRI. 总被引:9,自引:0,他引:9
Erik M Shapiro Kathryn Sharer Stanko Skrtic Alan P Koretsky 《Magnetic resonance in medicine》2006,55(2):242-249
The use of high-relaxivity, intracellular contrast agents has enabled MRI monitoring of cell migration through and homing to various tissues, such as brain, spinal cord, heart, and muscle. Here it is shown that MRI can detect single cells in vivo, homing to tissue, following cell labeling and transplantation. Primary mouse hepatocytes were double-labeled with green fluorescent 1.63-microm iron oxide particles and red fluorescent endosomal labeling dye, and injected into the spleens of recipient mice. This is a common hepatocyte transplantation paradigm in rodents whereby hepatocytes migrate from the spleen to the liver as single cells. One month later the animals underwent in vivo MRI and punctuated, dark contrast regions were detected scattered through the livers. MRI of perfused, fixed samples and labeled hepatocyte phantoms in combination with histological evaluation confirmed the presence of dispersed single hepatocytes grafted into the livers. Appropriate controls were used to determine whether the observed contrast could have been due to dead cells or free particles, and the results confirmed that the contrast was due to disperse, single cells. Detecting single cells in vivo opens the door to a number of experiments, such as monitoring rare cellular events, assessing the kinetics of stem cell homing, and achieving early detection of metastases. 相似文献
37.
Mathematical Models for Predicting the Epidemiologic and Economic Impact of Vaccination against Human Papillomavirus Infection and Disease 总被引:2,自引:1,他引:1
Infection with human papillomavirus (HPV) is the primary causeof cervical cancer, other anogenital cancers, genital warts,and recurrent respiratory papillomatosis. Clinical studies havedemonstrated that a prophylactic HPV vaccine can prevent infection,genital warts, and the precancerous lesions that lead to cervicalcancer. Given the absence of data on the long-term effectivenessof HPV vaccination, a number of mathematical models have beendeveloped to provide insight to policy makers by projectingthe long-term epidemiologic and economic consequences of vaccinationand evaluate alternative vaccination policies. This paper reviewsthe state of these models. Three types of HPV mathematical modelshave been reported in the literature: cohort, population dynamic,and hybrid. All have demonstrated that vaccination can significantlyreduce the incidence of cervical cancer in the long term. However,only the cohort and hybrid models have evaluated the cost-effectivenessof vaccination strategies for preventing cervical cancer. Thesemodels have generally shown that vaccinating females can becost-effective. None has accounted for the potential benefitsof vaccinating the population to reduce the burden of recurrentrespiratory papillomatosis and cancers of the vagina, vulva,anus, penis, and head/neck. Given that only the population dynamicmodel can account for both the direct and indirect (i.e., herdimmunity effects) benefits of vaccination in the population,future research should focus on further development of dynamicmodels by expanding the range of epidemiologic outcomes trackedand including the ability to assess the cost-effectiveness ofalternative vaccination policies. cost-benefit analysis economics papillomavirus, human vaccines 相似文献
38.
39.
A separation of the individual latex layers is a known complication of endotracheal armoured tubes manufactured by immersion technique. This can result in herniation into the lumen with obstruction of the tube. Diffusion of nitrous oxide into the inner hernia considerably intensifies the obstruction. This can lead to life-threatening situations. We observed a similar herniation caused by layer separation with subsequent tube obstruction of silicolatex anaesthesia tubes used in paediatric circuit systems. This is caused by manufacturing defects and above all by damage incurred in reprocessing. Therefore it is important to process the tubes carefully. A too-high drying temperature can cause premature layer separation. The tubes should never be processed more than 80 times. Routine examination of the tubes is imperative, especially at the predilection sites for layer separation. 相似文献
40.
NGF-like trophic support from peripheral nerve for grafted rhesus adrenal chromaffin cells 总被引:1,自引:0,他引:1
J H Kordower M S Fiandaca M F Notter J T Hansen D M Gash 《Journal of neurosurgery》1990,73(3):418-428
Autopsy results on patients and corresponding studies in nonhuman primates have revealed that autografts of adrenal medulla into the striatum, used as a treatment for Parkinson's disease, do not survive well. Because adrenal chromaffin cell viability may be limited by the low levels of available nerve growth factor (NGF) in the striatum, the present study was conducted to determine if transected peripheral nerve segments could provide sufficient levels of NGF to enhance chromaffin cell survival in vitro and in vivo. Aged female rhesus monkeys, rendered hemiparkinsonian by the drug MPTP (n-methyl-4-phenyl-1,2,3,6 tetrahydropyridine), received autografts into the striatum using a stereotactic approach, of either sural nerve or adrenal medulla, or cografts of adrenal medulla and sural nerve (three animals in each group). Cell cultures were established from tissue not used in the grafts. Adrenal chromaffin cells either cocultured with sural nerve segments or exposed to exogenous NGF differentiated into a neuronal phenotype. Chromaffin cell survival, when cografted with sural nerve into the striatum, was enhanced four- to eightfold from between 8000 and 18,000 surviving cells in grafts of adrenal tissue only up to 67,000 surviving chromaffin cells in cografts. In grafts of adrenal tissue only, the implant site consisted of an inflammatory focus. Surviving chromaffin cells, which could be identified by both chromogranin A and tyrosine hydroxylase staining, retained their endocrine phenotype. Cografted chromaffin cells exhibited multipolar neuritic processes and numerous chromaffin granules, and were also immunoreactive for tyrosine hydroxylase and chromogranin A. Blood vessels within the graft were fenestrated, indicating that the blood-brain barrier was not intact. Additionally, cografted chromaffin cells were observed in a postsynaptic relationship with axon terminals from an undetermined but presumably a host origin. 相似文献