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21.
We present a case of a pelvic ring fracture that was originally treated with anterior symphyseal plating and a misplaced percutaneous iliosacral screw. The anterior extraosseus portion of the misplaced 7.3-mm cannulated screw irritated the L5 nerve root, resulting in a radiculopathy. Subsequent surgery involved and mandated removing the bent screw after open identification and protection of the L5 nerve root to avoid further nerve damage; the sacroiliac joint was subsequently debrided and fused. This case represents a complication of acute percutaneous iliosacral screw fixation of pelvic ring injuries and the subsequent strategy for successful salvage.  相似文献   
22.
BACKGROUND: Laparoscopic colonic resection has gained popularity as a method to treat colonic diseases. The electrothermal bipolar vessel sealer (EBVS; LigaSure Atlas) is a modern device that allows the secure sealing of vessels with a diameter of up to 7 mm. The aim of the present study was to evaluate the suitability of the device for laparoscopic colonic surgery. METHODS: The immediate outcome of 114 consecutive patients who underwent a sigmoid or rectal resection was prospectively analyzed. The intention was to perform all operations with the EBVS for dissection and ligation of the mesenterial vessels. Details on patient characteristics, peroperative and postoperative complications, and postoperative recovery were recorded prospectively and analyzed. RESULTS: One hundred and fourteen patients were scheduled for elective left-sided colonic or rectal resection. Massive intra-abdominal adhesions in 1 patient required a conversion of the laparoscopic procedure to an open one; In total, 113 laparoscopic operations were thus performed. The mean operative time was 87.7 +/- 2.8 minutes, and the mean time for patients to tolerate solid food was 3.4 +/- 0.1 days and the time to discharge from hospital was 4.6 +/- 0.2 days. There were nine (8.0%) general complications, and additionally, 10.6% of patients suffered from surgical complications. CONCLUSIONS: The electrothermal bipolar vessel sealer is suitable and safe for laparoscopic sigmoid and rectal resections. The use of the device probably reduces the operative time.  相似文献   
23.
The aim of this study was to analyse the influence of gender and children on physicians' stress and burnout and to obtain information on the compromises physicians make between family and work. The study was based on a nationwide survey of 3313 Finnish physicians. The results showed that work was the commonest reason for stress for both male and female physicians. If physicians had children, combining work and family was the commonest reason for stress among the women, but work still remained the commonest reason for stress among the men. The female physicians had made compromises between family and work more often than the male physicians (limited the number of children, delayed having children, given up postgraduate or continuing medical education, worked part‐time because of family, and given up a job because of a spouse's need to move). The female physicians—with or without children—were more likely than the male physicians to experience severe or moderate exhaustion and less likely than the male physicians to experience cynicism as components of burnout. Among both genders of physicians, having children was associated with less cynicism and reduced personal accomplishment, but the children did not affect exhaustion. In conclusion, having children is associated with a lower level of some burnout symptoms. Additional studies are needed to explain the health effects of work–family balance for physicians. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
24.
The activity of androgen receptor (AR) is modulated by a polymorphic CAG trinucleotide repeat in the AR gene. In the present study, we investigated hormonal changes among ageing men, and whether the number of AR CAG triplets is related to the appearance of these changes, as well as symptoms and diseases associated with ageing. A total of 213 41-70-year-old men donated blood for hormone analyses (LH, testosterone, oestradiol and SHBG) and answered questions concerning diseases and symptoms associated with ageing and/or androgen deficiency. Of these men, 172 donated blood for the measurement of the CAG repeat length of AR. The CAG repeat region of the AR gene was amplified by polymerase chain reaction (PCR) and the products were sized on polyacrylamide gels. The repeat number was analysed as a dichotomized variable divided according to cut-off limits of the lowest (< or =20 repeats) and the highest quartile (> or =23 repeats), and as a continuous variable. The proportion of men with serum LH in the uppermost quartile (>6.0 IU/L) with normal serum testosterone (>9.8 nmol/L, above the lowest 10%) increased significantly with age (p = 0.01). There were fewer men with this hormonal condition among those with CAG repeat number in the uppermost quartile (> or =23 repeats) (p = 0.03). These men also reported less decreased potency (p < 0.05). The repeat number was positively correlated with depression, as expressed by the wish to be dead (r = 0.45; p < 0.0001), depressed mood (r = 0.23; p = 0.003), anxiety (r = 0.15; p < 0.05), deterioration of general well-being (r = 0.22; p = 0.004), as well as decreased beard growth (r = 0.49; p < 0.0001). A hormonal condition where serum testosterone is normal but LH increased is a frequent finding in male ageing. Only certain types of age-related changes in ageing men were associated with the length of the AR gene CAG repeat, suggesting that this parameter may play a role in setting different thresholds for the array of androgen actions in the male.  相似文献   
25.
There has never been an MRI study of tunnel widening comparing bioabsorbable to metal screw fixation in autologous hamstring anterior cruciate ligament (ACL) reconstruction. We randomized 62 patients to hamstring ACL reconstruction with either a bioabsorbable (n = 31) or metal screw (n = 31) fixation. The evaluation methods were clinical examination, KT-1000 arthrometric measurement, the International Knee Documentation Committee and Lysholm scores, and MRI. There were no differences between the groups preoperatively. Fifty-five patients (89%) were available at a minimum of 2-year follow-up (range 24–36 months). There was tunnel widening in both groups, but the increase was significantly greater in the AP dimension of the femoral tunnel in the bioabsorbable screw group compared to metal group (P = 0.01). The tibial tunnels showed no intergroup difference. Ninety-four percent of the knees were normal or nearly normal according to the IKDC scores and the average Lysholm score was 91 with no intergroup difference. The follow-up AP tibial tunnel diameter was smaller with normal knee laxity compared to abnormal knee laxity. The graft failure rate in the bioabsorbable screw group was 23% (7/31 patients) and 6% (2/31 patients) in the metal screw group. The use of bioabsorbable screws resulted in more femoral tunnel widening, and more graft failures compared to metal screws. The tunnel widening in the tibia was associated with the knee laxity (P = 0.02).  相似文献   
26.
Effects of physical activity on bone properties, when controlled for genetic effects, are not fully understood. We aimed to study the association between long‐term leisure time physical activity (LTPA) and bone properties using twin pairs known to be discordant for leisure time physical activity for at least 30 yr. Volumetric BMD and geometric properties were measured at the tibia shaft and distal end using pQCT in 16 middle‐aged (50–74 yr) same‐sex twin pairs (seven monozygotic [MZ] and nine dizygotic [DZ] pairs) selected from a population‐based cohort. Paired differences between active and inactive co‐twins were studied. Active members of MZ twin pairs had larger cortical bone cross‐sectional area (intrapair difference: 8%, p = 0.006), thicker cortex (12%, p = 0.003), and greater moment of inertia (Imax, 20%, p = 0.024) at the tibia shaft than their inactive co‐twins. At the distal tibia, trabecular BMD (12%, p = 0.050) and compressive strength index (18%, p = 0.038) were also higher in physically active MZ pair members than their inactive co‐twins. The trends were similar, but less consistently so, in DZ pairs as in MZ pairs. Our genetically controlled study design shows that LTPA during adulthood strengthens bones in a site‐specific manner, that is, the long bone shaft has a thicker cortex, and thus higher bending strength, whereas the distal bone has higher trabecular density and compressive strength. These results suggest that LTPA has a potential causal role in decreasing the long‐term risk of osteoporosis and thus preventing osteoporotic fractures.  相似文献   
27.

OBJECTIVE

We investigated the effects of 18 confirmed type 2 diabetes risk single nucleotide polymorphisms (SNPs) on insulin sensitivity, insulin secretion, and conversion of proinsulin to insulin.

RESEARCH DESIGN AND METHODS

A total of 5,327 nondiabetic men (age 58 ± 7 years, BMI 27.0 ± 3.8 kg/m2) from a large population-based cohort were included. Oral glucose tolerance tests and genotyping of SNPs in or near PPARG, KCNJ11, TCF7L2, SLC30A8, HHEX, LOC387761, CDKN2B, IGF2BP2, CDKAL1, HNF1B, WFS1, JAZF1, CDC123, TSPAN8, THADA, ADAMTS9, NOTCH2, KCNQ1, and MTNR1B were performed. HNF1B rs757210 was excluded because of failure to achieve Hardy-Weinberg equilibrium.

RESULTS

Six SNPs (TCF7L2, SLC30A8, HHEX, CDKN2B, CDKAL1, and MTNR1B) were significantly (P < 6.9 × 10−4) and two SNPs (KCNJ11 and IGF2BP2) were nominally (P < 0.05) associated with early-phase insulin release (InsAUC0–30/GluAUC0–30), adjusted for age, BMI, and insulin sensitivity (Matsuda ISI). Combined effects of these eight SNPs reached −32% reduction in InsAUC0–30/GluAUC0–30 in carriers of ≥11 vs. ≤3 weighted risk alleles. Four SNPs (SLC30A8, HHEX, CDKAL1, and TCF7L2) were significantly or nominally associated with indexes of proinsulin conversion. Three SNPs (KCNJ11, HHEX, and TSPAN8) were nominally associated with Matsuda ISI (adjusted for age and BMI). The effect of HHEX on Matsuda ISI became significant after additional adjustment for InsAUC0–30/GluAUC0–30. Nine SNPs did not show any associations with examined traits.

CONCLUSIONS

Eight type 2 diabetes–related loci were significantly or nominally associated with impaired early-phase insulin release. Effects of SLC30A8, HHEX, CDKAL1, and TCF7L2 on insulin release could be partially explained by impaired proinsulin conversion. HHEX might influence both insulin release and insulin sensitivity.Impaired insulin secretion and insulin resistance, two main pathophysiological mechanisms leading to type 2 diabetes, have a significant genetic component (1). Recent studies have confirmed 20 genetic loci reproducibly associated with type 2 diabetes (213). Three were previously known (PPARG, KCNJ11, and TCF7L2), whereas 17 loci were recently discovered either by genome-wide association studies (SLC30A8, HHEX-IDE, LOC387761, CDKN2A/2B, IGF2BP2, CDKAL1, FTO, JAZF1, CDC123/CAMK1D, TSPAN8/LGR5, THADA, ADAMTS9, NOTCH2, KCNQ1, and MTNR1B), or candidate gene approach (WFS1 and HNF1B). The mechanisms by which these genes contribute to the development of type 2 diabetes are not fully understood.PPARG is the only gene from the 20 confirmed loci previously associated with insulin sensitivity (14,15). Association with impaired β-cell function has been reported for 14 loci (KCNJ11, SLC30A8, HHEX-IDE, CDKN2A/2B, IGF2BP2, CDKAL1, TCF7L2, WFS1, HNF1B, JAZF1, CDC123/CAMK1D, TSPAN8/LGR5, KCNQ1, and MTNR1B) (6,12,13,1638). Although associations of variants in HHEX (1622), CDKAL1 (6,2126), TCF7L2 (22,2730), and MTNR1B (13,31,32) with impaired insulin secretion seem to be consistent across different studies, information concerning other genes is limited (12,1825,27,3338). The mechanisms by which variants in these genes affect insulin secretion are unknown. However, a few recent studies suggested that variants in TCF7L2 (22,3942), SLC30A8 (22), CDKAL1 (22), and MTNR1B (31) might influence insulin secretion by affecting the conversion of proinsulin to insulin. Variants of FTO have been shown to confer risk for type 2 diabetes through their association with obesity (7,16) and therefore were not included in this study.Large population-based studies can help to elucidate the underlying mechanisms by which single nucleotide polymorphisms (SNPs) of different risk genes predispose to type 2 diabetes. Therefore, we investigated confirmed type 2 diabetes–related loci for their associations with insulin sensitivity, insulin secretion, and conversion of proinsulin to insulin in a population-based sample of 5,327 nondiabetic Finnish men.  相似文献   
28.
Benign epithelioid peripheral nerve sheath tumors (BEPNSTs) have not been fully characterized, and their relationship to conventional schwannoma and neurofibroma has not been satisfactorily established. Herein, we detail the clinicopathologic features of 33 examples of BEPNST. The study included 22 females and 11 males ranging in age from 2 to 68 years (median, 31.5 years). Only one patient probably has neurofibromatosis type 1. The tumors were predominantly dermal/subcutaneous in location (85%) and involved the lower limb (n=15), upper limb (n=11), trunk (n=4), and head/neck (n=3). The lesions ranged in size from 0.3 to 6.8 cm (median, 1.1 cm). Microscopically, the tumors were generally well-circumscribed, uninodular, or multinodular masses. Twenty-six lesions were encapsulated. Tumors consisted of trabeculae, loosely arranged nodules, and cohesive nests of epithelioid tumor cells immersed in collagenous, myxohyaline, or chiefly myxoid stroma. A bland spindled cell component comprising 5% to 40% of the tumor was noted in 15 cases. Mitotic activity ranged from 0 to 6 mitoses/50 high power fields (mean, 1.5 mitoses/50 high power fields) with no abnormal division figures identified. Five lesions were considered atypical based on presence of focal nuclear/nucleolar enlargement and hyperchromasia. Immunohistochemical reactivity for Schwann cell-related markers in tumor cells included S-100 protein (20 of 20 cases), collagen type IV (10 of 10), laminin (8 of 8), nerve growth factor receptor, p75(7 of 8), CD57 (6 of 9), and glial fibrillary acidic protein (8 of 15). CD34-positive fibroblast-like cells were identified in all 12 neoplasms tested. Anti-epithelial membrane antigen highlighted perineurial cells in 9 of the 11 encapsulated tumors. Anti-neurofilament protein did not identify intralesional neuraxons in the 10 tumors evaluated. Eighteen tumors were subtyped as epithelioid neurofibromas. The remaining 15 cases showed some histologic features suggestive of schwannoma, but their uniform cellularity, absence of nuclear palisading, and presence of a significant CD34-positive spindled cell population in 5 cases led to their classification as "BEPNST of indeterminate histogenesis." Evaluation for loss of heterozygosity in 2 cases demonstrated deletion of genetic material on chromosome 22q and 17q involving NF2 and NF1 loci. However, sequencing of NF2 coding sequences revealed no mutations. Follow-up for 18 patients (median interval, 13.5 years), including 4 patients with tumors exhibiting cytologic atypia, revealed a nondestructive recurrence or persistent disease in 3 patients whose tumors lacked atypia, but no evidence of metastatic spread or tumor-related death. BEPNSTs are usually small neoplasms located in superficial soft tissue and have an excellent prognosis after complete local excision. Accurate subclassification of some of these lesions is difficult based on currently available techniques.  相似文献   
29.
Sinus arrhythmia, sinus pauses and A-V blocks may occur during REM sleep, during which an increase in the variability of blood pressure and heart rate occurs. Peak mortality for myocardial infarction (MI) occurs between 4.00 and 7.00 am and there is a circadian variation in myocardial ischaemia. The incidence of MI is higher in those sleeping more than nine hours as compared to those sleeping 7-8 hours, while those sleeping less than six hours have more symptomatic coronary heart disease (CHD). Poor sleep quality also increases the risk of CHD and seems to be an indicator of mental and somatic disease. Other major factors are obesity and snoring, since habitual snoring increases the risk of hypertension and CHD. During obstructive sleep apnoea syndrome (OSAS) the pulmonary and systemic arterial pressures rise, straining the heart, and hypoxaemia increases vulnerability to fatal arrhythmias. Chronic obstructive pulmonary disease is another risk factor and part of the association between CHD and sleep disturbances could be explained even by modifications in lipoprotein catabolism.  相似文献   
30.
OBJECTIVE: To investigate the value of serum antitissue transglutaminase IgA antibodies (IgA-TTG) and IgA antiendomysial antibodies (IgA-EMA) in the diagnosis of coeliac disease in cohorts from different geographical areas in Europe. The setting allowed a further comparison between the antibody results and the conventional small-intestinal histology. METHODS: A total of 144 cases with coeliac disease [median age 19.5 years (range 0.9-81.4)], and 127 disease controls [median age 29.2 years (range 0.5-79.0)], were recruited, on the basis of biopsy, from 13 centres in nine countries. All biopsy specimens were re-evaluated and classified blindly a second time by two investigators. IgA-TTG were determined by ELISA with human recombinant antigen and IgA-EMA by an immunofluorescence test with human umbilical cord as antigen. RESULTS: The quality of the biopsy specimens was not acceptable in 29 (10.7%) of 271 cases and a reliable judgement could not be made, mainly due to poor orientation of the samples. The primary clinical diagnosis and the second classification of the biopsy specimens were divergent in nine cases, and one patient was initially enrolled in the wrong group. Thus, 126 coeliac patients and 106 controls, verified by biopsy, remained for final analysis. The sensitivity of IgA-TTG was 94% and IgA-EMA 89%, the specificity was 99% and 98%, respectively. CONCLUSIONS: Serum IgA-TTG measurement is effective and at least as good as IgA-EMA in the identification of coeliac disease. Due to a high percentage of poor histological specimens, the diagnosis of coeliac disease should not depend only on biopsy, but in addition the clinical picture and serology should be considered.  相似文献   
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