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101.
The 22q11.2 deletion syndrome (velocardiofacial/DiGeorge syndrome)is a neurogenetic condition associated with visuospatial deficits,as well as elevated rates of attentional disturbance, mood disorder,and psychosis. Previously, we detected pronounced cortical thinningin superior parietal and right parieto-occipital cortices inpatients with this syndrome, regions critical for visuospatialprocessing. Here we applied cortical pattern-matching algorithmsto structural magnetic resonance images obtained from 21 childrenwith confirmed 22q11.2 deletions (ages 8–17) and 13 demographicallymatched comparison subjects, in order to map cortical thicknessacross the medial hemispheric surfaces. In addition, corticalmodels were remeshed in frequency space to compute their surfacecomplexity. Cortical maps revealed a pattern of localized thinningin the ventromedial occipital–temporal cortex, criticalfor visuospatial representation, and the anterior cingulate,a key area for attentional control. However, children with 22q11.2DSshowed significantly increased gyral complexity bilaterallyin occipital cortex. Regional gray matter volumes, particularlyin medial frontal cortex, were strongly correlated with bothverbal and nonverbal cognitive functions. These findings suggestthat aberrant parieto-occipital brain development, as evidencedby both increased complexity and cortical thinning in theseregions, may be a neural substrate for the deficits in visuospatialand numerical understanding characteristic of this syndrome.  相似文献   
102.
In most Western countries, screening mammography and breast-conserving therapy (BCT) are now well-established practices and have been well accepted by women over the last two decades. There are limited data on the acceptability of these strategies by Chinese women in an Oriental society where a population-based screening program has not been established and mastectomy is still commonly practiced. A survey was conducted of 1012 Hong Kong Chinese women, ages 18-69 years, to assess the level of knowledge, perceptions, and attitudes on screening mammography and the surgical management of early breast cancer. Most women (58%) had never heard of mammographic screening, and housewives were more likely to have heard of it than nonhousewives (49% versus 37%; p = 0.0001). The majority (82%) of those who had heard of mammographic screening believe that it can detect early breast cancers and reduce mortality, however, only 58% of these women would participate in yearly screening and clinical breast examination despite acknowledging the potential benefits; a lack of time and the cost were the predominant reasons given. Forty-seven percent of women had the misconception that mastectomy was the only curative treatment; when the alternative was explained, the overall rate for choosing BCT rose from 29% to 49%. There was no correlation between age and the choice of surgery. Most women (75%) felt that breast reconstruction after mastectomy was desirable and acceptable. A lack of knowledge on mammographic screening is prevalent and the concept of preventive health care has a low priority in this Chinese population. Mastectomy is still widely perceived as the only curative treatment; BCT with cosmetic reconstruction is seen as an acceptable alternative. Interventions to improve the accuracy of information and to encourage preventive health care behaviors will have a positive impact on establishing cancer screening programs and providing quality cancer care in the future.  相似文献   
103.
Background: Animal and volunteer studies indicate that ropivacaine is associated with less neurologic and cardiac toxicity than bupivacaine. Ropivacaine may offer advantages when used for thoracic paravertebral block. This study was designed to describe the pharmacokinetics of ropivacaine after thoracic paravertebral block.

Methods: Twenty female patients undergoing elective unilateral breast surgery were randomly assigned to receive a single bolus thoracic paravertebral injection of 2 mg/kg ropivacaine, with or without 5 [mu]g/ml epinephrine. Simultaneous arterial and venous blood samples were obtained for plasma ropivacaine assay. Data were analyzed with NONMEM, using two possible absorption models: conventional first-order absorption and absorption following the inverse gaussian density function.

Results: Epinephrine reduced the peak plasma concentrations and delayed the time of peak concentration of ropivacaine in both the arterial and venous blood. The time course of drug input into the systemic circulation was best described by two inverse gaussian density functions. The median bioavailability of the rapid component was approximately 20% higher when epinephrine was not used. The mean absorption times were 7.8 min for the rapid absorption phase and 697 min for the slow absorption phase, with wide dispersion of the absorption function for the acute phase. The half-time of arterial-venous equilibration was 1.5 min.  相似文献   

104.
We hypothesized that the bisphosphonate zoledronic acid (ZA) could improve femoral head sphericity in Perthes disease by changing the balance between bone resorption and new bone formation. This study tests the effect of ZA in an established model of Perthes disease, the spontaneously hypertensive rat (SHR). One hundred and twenty 4-week old SHR rats were divided into three groups of 40: saline monthly, 0.015 mg/kg ZA weekly, or 0.05 mg/kg ZA monthly. At 15 weeks DXA measurements documented that femoral head BMD was increased by 18% in ZA weekly and 21% in ZA monthly compared to controls (p<0.01). Femoral head sphericity in animals with osteonecrosis was improved in ZA-treatment groups (p<0.01) as measured by epiphyseal quotient (EQ). The proportion of "flat" heads (EQ0.40) was significantly reduced from 32% in saline-treated animals to 12% in weekly ZA and 3% in monthly ZA (p<0.01). Histologically there was a similar prevalence of osteonecrosis in all groups. The prevalence of ossification delay was significantly reduced by ZA treatment (p<0.01). Zoledronic acid favorably altered femoral head shape in this spontaneous model of osteonecrosis in growing rats. Translation of these results to Perthes disease could mean that deformity of the femoral head may be modified in children, perhaps reducing the need for surgical intervention in childhood and adult life.  相似文献   
105.
OBJECTIVE: To determine whether identity badges and lanyards worn by health care workers (HCWs) are capable of harbouring potentially pathogenic bacteria. DESIGN, SETTING AND PARTICIPANTS: Cross-sectional study of 71 HCWs (59 clinical ward staff and 12 infection control staff) at Monash Medical Centre, a university teaching hospital. Samples from lanyards, identity badge surfaces and connections (eg, clips, keys, pens) were cultured. The study was conducted from July to August 2006. MAIN OUTCOME MEASURES: Presence of pathogenic bacteria on identity badges and lanyards; differences in bacterial counts on items carried by nurses and doctors. RESULTS: A total of 27 lanyards were identified with pathogenic bacteria, compared with 18 badges. Analysing lanyards and badges as a combined group, seven had methicillin-resistant Staphylococcus aureus, 29 had methicillin-sensitive S. aureus (MSSA), four had Enterococcus spp and five had aerobic gram-negative bacilli. Lanyards were found to be contaminated with 10 times the median bacterial load per area sampled compared with identity badges. There were no significant differences between nurses and doctors in total median bacterial counts on items carried, but doctors had 4.41 times the risk of carrying MSSA on lanyards (95% CI, 1.14-13.75). CONCLUSION: Identity badges and lanyards worn by HCWs may be contaminated with pathogenic bacteria, which could be transmitted to patients. In view of this finding we suggest appropriate infection control interventions.  相似文献   
106.
Indolent CD8+ cutaneous lymphoid proliferation represents a recently described entity among cutaneous T‐cell lymphomas that typically presents with solitary skin lesions on the face or at acral sites and usually follows an indolent clinical course. Histopathologically, this entity is characterized by a dense dermal infiltrate of non‐epidermotropic, small‐ to medium‐sized pleomorphic CD8+ T‐cells of the non‐activated cytotoxic phenotype showing a clear‐cut grenz zone and a low proliferation index. Distinction from otherwise aggressive T‐cell lymphomas bearing a cytotoxic CD8+ phenotype is fundamental. We herein present an unusual case of indolent CD8+ cutaneous lymphoid proliferation presenting in bilateral symmetrical distribution on both feet and lacking the otherwise described grenz zone. Our case widens the spectrum of possible clinical and histomorphological variations of this entity. Taking into account the distinctive and unique clinical and microscopic features of all hitherto published cases of indolent CD8+ cutaneous lymphoid proliferation we suppose that this lymphoma subtype has to be included as a new and distinct entity in the World Health Organisation (WHO)‐/European Organisation for Research and Treatment of Cancer (EORTC)‐classification of cutaneous lymphomas.  相似文献   
107.
Dacryocystorhinostomy is still the standard procedure complete stenosis of the nasolacrimal duct. New methods try to preserve the natural lacrimal pathway. Song implanted in 1995 a nasolacrimal polyurethane stent through the nasolacrimal duct. The results and complications of this new method are described in this prospective study. METHODS: Thirty consecutive patients with complete obstruction of the nasolacrimal duct or lacrimal sac were included in the study. The stenosis was localized by dacryocystography. The ages ranged from 22 to 87 years (mean, 58.9 +/- 16 years). Dacryocystography was performed immediately, 4 weeks and 8 months after the procedure to verify the position and patency of the stent. RESULTS: Twenty-five short (35 mm) and 5 long (45 mm) stents were implanted. Twenty-four of 30 patients after 4 weeks and 9 of 10 patients after 8 months had reduced or no complaints. In 1 patient the stent was obstructed. Forceful irrigation with saline solution permitted recanalization. In 1 patient the stent had moved into the upper canaliculus. Because of irritation of the canaliculus it had to be pulled out after 2 months. CONCLUSION: The follow-up is still too short to recommend stent implantation as a real alternative to dacryocystorhinostomy. The main advantages are that the procedure is faster, no incision is necessary, and the local anesthesia is easier. The disadvantage is the need for X-ray examination.  相似文献   
108.
BACKGROUND: Histopathological studies of acute multiple evanescent white dot syndrome (MEWDS) have not been reported because of the transient and benign nature of the disease. Ultrahigh resolution optical coherence tomography (UHR-OCT), capable of high resolution in vivo imaging, offers a unique opportunity to visualize retinal microstructure in the disease. METHODS: UHR-OCT images of the maculae of five patients with MEWDS were obtained and analyzed. Diagnosis was based on clinical presentation, examination, visual field testing, and angiography. RESULTS: UHR-OCT revealed disturbances in the photoreceptor inner/outer segment junction (IS/OS) in each of the five patients (six eyes) with MEWDS. In addition, thinning of the outer nuclear layer was seen in the case of recurrent MEWDS, suggesting that repeated episodes of MEWDS may result in photoreceptor atrophy. CONCLUSIONS: Subtle disruptions of the photoreceptor IS/OS are demonstrated in all eyes affected by MEWDS. UHR-OCT may be a useful adjunct to diagnosis and monitoring of MEWDS.  相似文献   
109.
婚前性行为,即使像意外怀孕或性病(包括艾滋病)等躯体的不良后果能加以避免,也难免留下心理上的后果。非婚姻的心理尚不成熟的青少年所涉及的性关系会在人的心灵深处留下伤痕。虽然眼睛看不见此种伤痕,但却是真实地存在着而且会造成终生影响。很少有人公开谈论在没有婚盟的情况下发生性关系所造成的心理影响,这种影响,通常深藏在潜意识的  相似文献   
110.
Skin biopsies from patients with psoriasis and normal controls were examined for the expression of cell adhesion molecules including intercellular adhesion molecule-1 (ICAM-1) endothelial leukocyte adhesion molecule-1 (ELAM-1), HECA-452 and 4D10, using an immunoperoxidase techique. This study demonstrates that psoriatic skin exhibits a wide variety of markers of endothelial cell activation which are either induced or increased expression (ICAM-1, ELAM-1 & 4D10). Moreover, ICAM-1 & HECA-452 are also on leukocytes. These antigens may facilitate the adhesion of inflammatory cells to endothelium and antigen-presenting cells in psoriatic skin. Thus, they may play a role in faciliating the infiltration of leukocytes into psoriatic skin.  相似文献   
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