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71.
72.
Impaired executive functioning is found in a considerable proportion of schizophrenia patients. Neuropsychological tests are originally designed to measure the behavior of neurological patients and may therefore miss psychiatry-related cognitive deficits. Qualitative information on tests for executive functioning is important in psychiatric populations. The Modified Six Elements Test (MSET) is a planning test that consists of 6 tasks, for which subjects have limited time and have to obey to switching rules. This study concerns a qualitatively different approach schizophrenia patients use on the MSET, and its relationship with cognitive measures. MSET scores and strategies of schizophrenia patients were compared to those of healthy controls, closed-head-injury patients, and peripheral injury patients. Also, schizophrenia patients and healthy controls were compared on verbal memory and vigilance. Schizophrenia patients finish fewer assignments on the MSET, receive a lower profile score compared to healthy controls, and use a different strategy on the test compared to the other groups. They also perform below healthy controls on the tests for verbal memory and vigilance. Use of the different strategy in schizophrenia patients was related to impaired cognitive functioning. An interesting strategy used by schizophrenia patients on the MSET appears to be indicative of impaired cognitive functioning. This strategy may be a compensatory strategy to spare cognitive resources. It could also be the result of a concrete interpretation of the test instructions.  相似文献   
73.
BackgroundAccumulating evidence suggests anatomical and functional differences in connectivity between the anterior and posterior parts of the inferior-parietal lobule (IPL) and the frontal motor areas.Objective/HypothesisThis study investigates whether different intra-hemispheric parietal-motor interactions can be observed along the anterior–posterior axis of the IPL in the resting human brain.MethodsWe use a twin coil transcranial magnetic stimulation technique to test intra-hemispheric interactions between three points adjacent to the intra-parietal sulcus (anterior, central, posterior) and the ipsilateral primary motor cortex (M1) at rest in both hemispheres.ResultsWe found that stimulation of the anterior IPL resulted in an inhibition of the ipsilateral M1 in both hemispheres. Stimulation of the central and posterior IPL resulted in a facilitatory effect on ipsilateral M1 in the left but not for the right hemisphere. Additionally we show that there is considerable inter-subject variability concerning the optimal parietal facilitatory and inhibitory position.ConclusionsThe IPL has distinct inhibitory and facilitatory connections to the ipsilateral M1. Whereas inhibitory connections are observed in both hemispheres, facilitatory connections are asymmetric. These parietal-motor networks may represent the basis for the functional differences between these regions in reaching and grasping tasks and mirror the functional asymmetry observed in the motor system. From a practical point of view, we note that the inter-subject variability means that future TMS studies of the parietal area might consider a hot-spot localization similar to the procedures commonly used for M1.  相似文献   
74.
Internal herniation, defined as a protrusion of the bowel through a peritoneal or mesenteric aperture into a compartment of the abdominal cavity, is a potentially serious complication following Roux-en-Y gastric bypass. In view of the high risk of strangulation and volvulus with possible progression to necrotic bowel, sepsis and multiple organ failure, early diagnosis and prompt surgical intervention are crucial to minimise morbidity and mortality rates. As little is known about internal herniation, pathogenesis, consequences, clinical presentation and diagnostic approach are discussed in this article. A review of the literature and the consideration of three cases make it clear that diagnosis is often delayed due to a vague, non-specific clinical presentation and the frequently negative radiological investigations. Displacement of the superior mesenteric artery (SmA) with crowding, stretching and engorgement of its visceral branches, mesenteric swirl and a clustered appearance of small bowel loops are CT findings with a high specificity but low sensitivity. A high degree of vigilance, communication between radiologists and surgeons and a low threshold for surgical exploration is therefore necessary.  相似文献   
75.
ObjectiveRecent case reports suggest a link between reduced melanocortinergic tone and both obesity and attention deficit / hyperactivity disorder (ADHD). We present the case of a 13-year-old, male, obese MC4R mutation carrier with ADHD.Case ReportThe boy carries a heterozygous mutation in the melanocortin 4 receptor gene (MC4R; Met281Val), that leads to a reduced receptor function. Dominant mutations of this type represent major gene effects for obesity. He participated in a lifestyle intervention program for obesity and received treatment with the selective norepinephrine re-uptake inhibitor atomoxetine for 31 months. The boy markedly reduced his BMI from 47.2 to 29.6 kg/m².ConclusionAtomoxetine proved to efficiently reduce weight in a severely obese MC4R mutation carrier with ADHD. We briefly discuss possible mechanisms for our observation, including evidence for the functional connectivity between melanocortinergic, dopaminergic, and norepinephrinergic brain circuitries.Key Words: Pharmacogenetics, Brain-derived neurotrophic factor, Weight loss, Appetite control, Methylphenidate  相似文献   
76.

Objective

Caries adjacent to restorations is one of the main causes for restoration replacement. Antimicrobial substances incorporated into dental materials would potentially be able to reduce secondary caries initiation and progression. This study investigated biofilm growth of Streptococcus mutans UA159 on the surface of composite materials containing the biomolecule carolacton compared to materials containing chlorhexidine (CHX) and triclosan.

Methods

Biofilm inhibition was investigated by counting colony forming units (CFU), viability staining (Life/Dead), and real-time quantitative PCR.

Results

First, the antimicrobial substances were added to the cultivation medium at 2.5 μg/ml (0.0002%) and 0.25 μg/ml (0.00002%). CHX eliminated bacterial growth and biofilm formation completely. Triclosan was effective at 2.5 μg/ml, but at 0.25 μg/ml biofilm mass and viability were unchanged, yet the number of CFU increased due to disruption of cell chains and biofilm aggregates. Carolacton had a limited effect on biofilm growth and mass, but reduced viability significantly. When incorporated into composite materials carolacton (25 μg/ml resp. 0.002%, w/w) had no adverse effect on physical/mechanical properties and retained its biofilm inhibiting effect. Life/Dead staining revealed a reduction of biofilm viability of up to 64%. CFUs were reduced by 98% and qPCR demonstrated a mean inhibition of 87%. In contrast, materials containing CHX or triclosan showed an insignificant effect on biofilm formation, even at a 100fold increased concentration (0.2%). The anti-biofilm activity of composite material containing carolacton was stable over a period of 42 days.

Significance

Carolacton incorporated into dental filling material has a strong biofilm-inhibiting effect on S. mutans and is therefore potentially able to prevent secondary caries formation.  相似文献   
77.
78.
79.

Purpose

The place of arthroscopic treatment in osteoarthritis of the knee has generated much controversy. A survey was initiated to collect the opinion of experienced surgeons.

Methods

Of the 211 surgeons interviewed, 170 (80.6 %) replied to the electronic questionnaire. Respondents had at least ten years of experience in arthroscopy and currently perform more than 100 arthroscopies per year. Various indications and treatment modalities for arthroscopy in osteoarthritis of the knee had to be evaluated on a scale from “excellent” to “no indication”.

Results

The respondents generally believe that an improvement is more likely in low-grade osteoarthritis (p < 0.001) and in neutral leg axis (p < 0.001). The outcome was rated better if symptoms had persisted for less than six months (p < 0.001) and for patients that were younger than 60 years (p < 0.001). Partial meniscectomy and notchplasty in cases of extension deficit were considered as successful treatment options. Debridement was an accepted indication, with an outcome mainly rated as fair. A majority saw no indication for joint lavage, arthroscopic treatment of arthrofibrosis and removal of osteophytes. The outcome appears to be poor if a bone edema is diagnosed on magnetic resonance imaging prior to arthroscopy. Only 55.9 % of respondents were comfortable with the current definition of osteoarthritis.

Conclusions

Experienced arthroscopic surgeons all over Europe believe arthroscopy in osteoarthritis is appropriate, under certain conditions. The major task for surgeons is to select the right patients who are likely to benefit from this intervention.  相似文献   
80.

Purpose

This nationwide study evaluated results of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal metastasis of colorectal origin in the Netherlands following a national protocol.

Methods

In a multi-institutional study prospective databases of patients with peritoneal carcinomatosis (PC) from colorectal cancer and pseudomyxoma peritonei (PMP) treated according to the Dutch HIPEC protocol, a uniform approach for the CRS and HIPEC treatment, were reviewed. Primary end point was overall survival and secondary end points were surgical outcome and progression-free survival.

Results

Nine-hundred sixty patients were included; 660 patients (69 %) were affected by PC of colorectal carcinoma and the remaining suffered from PMP (31 %). In 767 procedures (80 %), macroscopic complete cytoreduction was achieved. Three-hundred and thirty one patients had grade III–V complications (34 %). Thirty-two patients died perioperatively (3 %). Median length of hospital stay was 16 days (range 0–166 days). Median follow-up period was 41 months (95 % confidence interval (CI), 36–46 months). Median progression-free survival was 15 months (95 % CI 13–17 months) for CRC patients and 53 months (95 % CI 40–66 months) for PMP patients. Overall median survival was 33 (95 % CI 28–38 months) months for CRC patients and 130 months (95 % CI 98–162 months) for PMP patients. Three- and five-year survival rates were 46 and 31 % respectively in case of CRC patients and 77 and 65 % respectively in case of PMP patients.

Conclusions

The results underline the safety and efficacy of cytoreduction and HIPEC for PC from CRC and PMP. It is assumed the uniform Dutch HIPEC protocol was beneficial.  相似文献   
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