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81.
Background: The pathophysiology of the syndrome of conduction aphasia has been thought to involve a disconnection between posterior and anterior language areas. The arcuate fasciculus has been one of the principal candidates for an anatomical link between Wernicke's and Broca's area, but direct evidence for its involvement in conduction aphasia has been difficult to obtain. Aims: The purpose of this study was to examine white matter tract integrity, using the novel magnetic resonance imaging technique of diffusion tensor imaging, in a patient with transcortical aphasia. Methods & Procedures: A case study of a 55-year-old, right-handed man with aphasia following a left hemisphere stroke is reported. The patient's language performance was assessed with the Boston Diagnostic Aphasia Examination twice: at 10 days and at 2 years after his stroke. An MR diffusion tensor imaging study was obtained approximately 2 years after his stroke using the 1.5 T Phillips Gyroscan NT system. White matter fibre tracts maps were reconstructed using the “FACT” algorithm. Outcomes and Results: Ten days after his stroke, the patient had a non-fluent aphasia with marked impairment of both auditory comprehension and spontaneous speech. However, repetition was relatively intact. By 2 years, when the MR diffusion tensor imaging study was performed, repetition was completely normal and the patient had only subtle deficits in areas of naming and auditory comprehension. The MR diffusion tensor imaging study revealed a lesion of the dominant hemisphere arcuate fasciculus. Conclusions: This study documents normal repetition performance in a patient who on subsequent MR diffusion tensor imaging was found to have a lesion involving the dominant hemisphere arcuate fasciculus lesion. This case adds to previously published cases of normal repetition performance despite a documented lesion of the arcuate fasciculus, and thus further challenges the traditional model of conduction aphasia invoking a critical role of this white matter tract. Our case also suggests that MR diffusion tensor imaging may be a potentially useful technique to evaluate regional involvement of specific white matter tract projections in patients with aphasia.  相似文献   
82.
To investigate X-linked adrenoleukodystrophy in an unselected population, we performed a population based, cross-sectional prevalence study, supplemented by a retrospective study of deceased subjects. Sixty-three subjects (34 males, 29 females) belonging to 22 kindreds were included. Thirty-nine subjects (13 males, 26 females) were alive, and 24 (21 males, 3 females) were deceased on the prevalence day. The point prevalence of X-linked adrenoleukodystrophy in Norway on July 1, 2011, was 0.8 per 100,000 inhabitants. The incidence at birth in the period 1956-1995 was 1.6 per 100,000 inhabitants. An age-dependent penetrance was observed among males and females, with more severe phenotypes appearing with rising age. Only 5% of deceased males had not developed cerebral leukodystrophy. No female older than 50 years was neurologically intact. Sixteen mutations in the ABCD1 gene were identified. De novo mutations were found in 19% of probands. The frequency of X-linked adrenoleukodystrophy was lower in Norway than reported in the literature. A more severe natural course than previously reported was observed, indicating a need for better follow-up of both male and female patients. Given the high rate of de novo mutations, identification programs such as newborn screening may be required to offer timely treatment to all patients.  相似文献   
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Objective: To formulate solid lipid microparticles (SLMs) encapsulating doxycycline hydrochloride (DH) and metronidazole (MT) for the treatment of periodontal diseases.

Methods: SLMs were prepared applying hot homogenization method, using different types of lipids and stabilized with various types and concentrations of surfactants. The optimized formula was subjected to freeze-drying followed by incorporation into poloxamer gel. Microbiological and clinical evaluation of the selected SLMs on patients suffering from periodontal diseases was performed.

Results: SLMs could entrap high percentage of both drugs (81.14% and 68.75 % for doxycycline hydrochloride and metronidazole respectively). Transmission electron microscopy images of SLMs showed nearly spherical particles. Freeze-dried SLMs showed satisfactory stability for three months. Combined drugs were molecularly dispersed in SLMs. Incorporation of the freeze-dried SLMs powder in poloxamer gel could control the drugs release for 72 h. In-vivo study revealed effective and safe use of SLMs gel for periodontitis treatment. Significant improvement in both microbiological and clinical parameters was observed as compared to scaling and root planing alone.

Conclusion: The formulated SLMs gel offers an applicable dosage form that can be injected directly into the periodontal pocket as adjunctive to scaling and root planing.  相似文献   

85.

Background

Primary hyperparathyroidism (HPT) in multiple endocrine neoplasia type 1 (MEN1) is surgically treated with either a subtotal parathyroidectomy removing 3 or 3,5 glands (SPX), less than 3 glands (LSPX), or a total parathyroidectomy with autotransplantation (TPX). Previous studies with shorter follow-up have shown that LSPX and SPX are associated with recurrent HPT, and TPX with hypocalcemia and substitution therapy. We examined the situation after long-term follow-up (median 20,6 years).

Methods

Sixty-nine patients with MEN1 HPT underwent 110 operations, the first operation being 31 LSPX, 30 SPX, and 8 TPX. Thirty patients underwent reoperative surgery in median 120 months later, as completion to TPX (n = 12), completion of LSPX to SPX (n = 9), extirpation of single glands (n = 3) still resulting in LSPX, and resection of forearm grafts (n = 3). Nine patients underwent a second, and 2 a third reoperation. In 24 patients genetic testing confirmed MEN1, and in the remaining heredity and phenotype led to the diagnosis.

Results

TPX had higher risk for hypoparathyroidism necessitating substitution therapy, at latest follow-up 50 %, compared to SPX (16 % after 3–6 months; none at latest follow-up). Recurrent HPT was common after LSPX, leading to 24 reoperations in 17 patients. No need for substitution therapy after SPX indicated forthcoming recurrent disease. Not having hypocalcemia in the postoperative period and less radical surgery than TPX were significantly associated to risk for recurrence. Further, mutation in exon 3 in the MEN1 gene may eventually be linked to risk of recurrence.

Conclusion

LSPX is highly associated with recurrence and TPX with continuous hypoparathyroidism, also after long-term follow-up. SPX should be the chosen method in the majority of patients with MEN1 HPT.
  相似文献   
86.
Optical diagnosis techniques offer several advantages over traditional approaches, including objectivity, speed, and cost, and these label‐free, noninvasive methods have the potential to change the future workflow of cancer management. The oral cavity is particularly accessible and, thus, such methods may serve as alternate/adjunct tools to traditional methods. Recently, in vivo human clinical studies have been initiated with a view to clinical translation of such technologies. A comprehensive review of optical methods in oral cancer diagnosis is presented. After an introduction to the epidemiology and etiological factors associated with oral cancers currently used, diagnostic methods and their limitations are presented. A thorough review of fluorescence, infrared absorption, and Raman spectroscopic methods in oral cancer diagnosis is presented. The applicability of minimally invasive methods based on serum/saliva is also discussed. The review concludes with a discussion on future demands and scope of developments from a clinical point of view. © 2015 Wiley Periodicals, Inc. Head Neck 38 : E2403–E2411, 2016  相似文献   
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89.
Abnormal lung function in healthy preterm infants.   总被引:4,自引:0,他引:4  
The aim of this study was to assess the consequences of preterm birth for the functional development of the lungs. We studied 32 healthy preterm infants (gestational age 25 to 33 wk at birth) and 53 healthy full-term infants (37 to 42 wk) at the same mean postmenstrual age of 40 wk with a multibreath nitrogen washout technique to assess functional residual capacity (FRC), gas mixing efficiency, and dead space and with the single-breath occlusion technique to calculate compliance and resistance of the respiratory system. Twenty of the preterm infants were also assessed with the same methods at 34.2 (32 to 37) wk. At the same postmenstrual age the preterm infants had lower FRC/kg body weight, lower specific compliance, impaired gas mixing efficiency, and higher total and dead space ventilation/kg than the full-term infants. Specific compliance and specific conductance decreased but gas mixing efficiency increased from 34 to 40 wk. We conclude that premature exposure to extrauterine conditions changes lung function. Preterm infants showed signs of dysfunction of the terminal respiratory units and higher elastic recoil than infants who spent the corresponding time for development in utero. It is suggested that preterm birth per se affects alveolarization and formation of elastic tissue in the lungs.  相似文献   
90.
Seven patients were operated on for thoracic (n=2) or thoracoabdominal (n=5) aortic aneurysms during cross-clamping of the aorta. Interstitial tissue fluid pressure was measured at the neck during cross-clamping of the descending thoracic aorta by the wick-in-needle technique, whereas control measurements were obtained prior to cross-clamping. The subcutaneous interstitial fluid pressure was significantly higher on the neck during cross-clamping of the thoracic aorta compared with control measurements (median 3.7 mmHg vs –0.6 mmHg, p<0.05). Increased subcutaneous interstitial tissue pressure of the upper part of the body is probably caused by increased capillary filtration rate induced by inhibited autoregulatory functions during aortic cross-clamping. The pressure measurements objectively confirm the problem of edema formation of the head and neck during these operations. The edema may occasionally affect the upper airways and represent a problem for intubation of the patient in the postoperative phase.  相似文献   
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