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991.
Complete decapitation as a result of a suicidal hanging is rarely observed in forensic practice. The authors report a case of a 38-year-old man hanging fro  相似文献   
992.
We present a small child with febrile peaks and syncopal episodes secundary to ventricular tachycardia, in whom it was eventually possible to demostrate the Brugada Syndrome with a special presentation in the ECG; early repolarization pattern in lead I and a aVL and Brugada pattern during fever in V1‐V2. This is, to our knowledge, tha first case with this special ECG presentation in a small child.  相似文献   
993.
PurposeAmongst trauma patients, early coagulopathy is common on hospital admission. No studies have evaluated the initial coagulation status in the pre-hospital setting. We hypothesise that the coagulopathic process begins at the time of trauma. We studied the on-scene and on hospital arrival coagulation profile of trauma patients.MethodsProspective, observational study investigating the on-scene coagulation profile and its time course. We studied 45 patients at the scene of the accident, before fluid administration, and on hospital admission and classified their coagulopathy using the International Society on Thrombosis and Haemostasis score during a 2-month period. Prothrombin time, activated partial thromboplastin time, fibrinogen concentration, factors II, V and VII activity, fibrin degradation products, antithrombin and protein C activities, platelet counts and base deficit were measured.ResultsThe median injury severity score was 25 (13–35). On-scene, coagulation status was abnormal in 56% of patients. Protein C activities were decreased in the trauma-associated coagulopathy group (p = .02). Drops in protein C activities were associated with changes in activated partial thromboplastin time, prothrombin time, fibrinogen concentration, factor V and antithrombin activities. Only factor V levels decreased significantly with the severity of the trauma. On hospital admission, coagulation status was abnormal in 60% of patients. The on-scene coagulopathy was spontaneously normalised only in 2 patients whereas others had the same or a poorer coagulopathy status. All parameters of coagulation were significantly abnormal comparing to the on-scene phase. Decreases in protein C activities were related to the coagulation status (p < .0001) and changes in other coagulation parameters. Patients with base deficit ≤?6 mmol/L had changes in antithrombin, factor V and protein C activities but no significant coagulopathy.ConclusionCoagulopathy occurs very early after injury, before fluid administration, at the site of accident. Coagulation and fibrinolytic systems are activated early. The incidence of coagulopathy is high and its severity is related to the injury and not to hypoperfusion.  相似文献   
994.
The aim of this study was to determine the influence of the nature of the perigraft tissue in the healing pattern of high-porosity polytetrafluoroethylene (PTFE) vascular grafts. Nine-centimeter long segments of unreinforced experimental high-porosity (60 microns) PTFE grafts were placed as abdominal aortic interposition in mongrel dogs. Three grafts served as controls (group A); in five dogs (group B) a 25 x 25 cm piece of devascularized omentum was wrapped around the graft. In five dogs (group C) the omentum with its own vascular supply was completely wrapped around the graft. Animals were killed 4 weeks after surgery. The percentage of thrombus-free area was 31% in group A grafts, 39% in group B grafts, and 79% in group C grafts (p less than 0.01). Scanning electron microscopy showed many confluent areas of endothelium-like cells in the midportion of group C grafts, corresponding to capillary ingrowth. Transmural endothelial migration was more evident in group C grafts. We conclude that the nature of the perigraft tissue influences transmural capillary migration and the endothelialization rate of high-porosity PTFE grafts in dogs. Agents able to increase capillary formation in the perigraft tissue might improve endothelialization of vascular grafts.  相似文献   
995.
996.

Background

The insulin receptor substrate 1 (IRS1), phosphoinositide 3-kinase (Pi3k), protein kinase B (Akt1), Forkhead Box O3a (FOXO3a) pathway is directly involved in aging and ovarian activation of follicle growth. Therefore, the aim of this work was to measure the expression of genes related to the ovarian pathway for activation of primordial follicles and FOXO3a protein phosphorylation between young and old female Ames dwarf (df/df) and normal (N) mice.

Methods

For this study ovaries from N (n?=?10) and df/df (n?=?10) female mice were collected at 5–6 months of age and at 21–22 months of age. For immunohistochemistry ovaries from 12 month-old and df/df mice were used.

Results

The expression of Irs1, Pi3k, Akt1, mammalian target of rapamycin (Mtor), suppressor of cytokine signaling ?2 (Socs2), Socs3 was lower (P?<?0.05) in older than younger N mice and not different (P?>?0.05) between young and old df/df mice. The expression of Foxo3a was also lower (P?<?0.05) in old than younger N and df/df mice and was higher (P?<?0.05) in old df/df than N mice. Expression of Amh was lower (P?<?0.05) in old than young N and df/df mice and was higher (P?=?0.0009) in df/df than N mice. Imunnostaining for p-FOXO3 was lower in df/df than N mice (P?<?0.001), although FOXO3 immunostaining was not different (P?>?0.05) between df/df and N mice.

Conclusions

In sum, the present study indicates that lower expression of Irs1, Socs2, Socs3, Akt1, Pi3k, Mtor and Foxo3a mRNA in the ovaries of older mice of both genotypes is associated to a reduced ovarian activity revealed by lower expression of Amh mRNA. At the same time, ovaries of old df/df mice maintained higher expression of Foxo3a mRNA, which was associated to higher ovarian activity. We have shown that df/df females have a lower level of p-FOXO3 in oocytes from primordial/primary follicles, an important activator of follicular growth. Therefore, this study strongly indicates that Prop1df mutation causes delayed ovarian aging.
  相似文献   
997.
OBJECTIVE: To assess whether method of administration of a standard urinary symptom questionnaire alters the relationship of symptoms with urodynamic diagnoses. DESIGN: Randomised crossover study. SETTING: Tertiary Urogynaecology Unit, London, UK. PARTICIPANTS: One hundred and fourteen women attending a tertiary urogynaecology clinic. METHODS: Women were randomised to either an initial interview-assisted questionnaire in the clinic with a follow up postal questionnaire or an initial pre-outpatient questionnaire followed by an interview-assisted questionnaire at the clinic visit. Video cystourethrography or saline cystometry was performed at the clinic visit. MAIN OUTCOME MEASURES: Question responses were compared with urodynamic diagnoses. RESULTS: With an interview method, only severity of incontinence was significantly associated with detrusor overactivity (U= 593.5, P= 0.012). With self-completion, severity of nocturia (U= 477, P < 0.05), urgency (U= 395, P= 0.003), urge urinary incontinence (U= 392, P= 0.003), leakage without warning (U= 443, P= 0.035) and incomplete voiding (U= 413, P= 0.01) were significantly associated with detrusor activity. On interview the symptom of stress urinary incontinence (U= 523, P= 0.002) and use of pads (U= 564.5, P= 0.011) were significantly associated with a diagnosis of urodynamic stress incontinence. Severity of stress urinary incontinence (U= 276, P < 0.001), frequency of leakage (U= 348.5, P= 0.004), use of protection (U= 432.5, P < 0.018), nocturnal incontinence (U= 393.5, P= 0.002) and quantity of leakage (U= 441.5, P < 0.05) on self-completion were strongly associated with diagnosed urodynamic stress incontinence. There was no association between the symptoms of urgency or urge incontinence and the urodynamic stress incontinence. CONCLUSIONS: Postal questionnaire responses have a better relationship with urodynamics, both for urodynamic stress incontinence and detrusor over activity, than interview-assisted questionnaire responses. However, no symptom has a high enough specificity and sensitivity to replace urodynamic testing.  相似文献   
998.
This is an 8-year cohort study of 24 HIV-infected patients aged 5–17 years to assess body composition and metabolic changes after switching from lamivudine + stavudine (d4T) + protease inhibitors (PI) to lamivudine + tenofovir (TDF) + efavirenz (EFV). Body composition (dual-energy X-ray absorptiometry) and cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, glucose and insulin were measured annually. Linear mixed models and generalized linear mixed models were used to evaluate time changes of the outcome of interest. Body mass index increased linearly by 0.3 kg/m2/year (p?<?0.001); waist circumference increased non-linearly from 68 to 74 cm (p?=?0.004 for the linear term and p?=?0.04 for the quadratic term). Percent body fat, percent trunk fat and percent bone mineral content increased linearly by 0.6 %/year (p?=?0.005), 1.2 %/year (p?<?0.001) and 0.02 %/year (p?=?0.04), respectively. Percent arm fat remained stable (p?=?0.5), and percent leg fat decreased linearly by 1.2 %/year (p?<?0.001). The probability of low HDL was 0.2 % at baseline and remained stable during the study. The probability of high triglycerides was 3 % at baseline and increased linearly to become 11 % at the 8th year of follow-up (p?=?ns). The probability of high glucose was 1 % for the whole study duration. Conclusions: patients, after switching from d4T to TDF and from PI to EFV, show most of the changes in anthropometry and body composition associated with normal growth and no frankly pathological change in metabolic parameters.  相似文献   
999.
AIM: To determine the prevalence and risk factors associated with Helicobacter pylori infection among children up to 6 years. METHODS: Cross-sectional study carried out in a poor urban community in Fortaleza Northeast Brazil. A standardized questionnaire was applied. Helicobacter pylori status was evaluated by (13)C-urea breath test ((13)C-UBT) in children up to 48 months and by ELISA in the mothers. Sera were assayed by the Cobas Core anti-H. pylori IgG EIA. RESULTS: The overall prevalence of H. pylori infection was 40% (88/217), 41% (46/112) boys and 40% (42/105) girls were infected. The prevalence rate of infection by H. pylori increased significantly with age, from 29% (27/93) in the youngest group (3 months to 2 years) to 59% (35/59) in the oldest group (6 years), (p < 0.001). There was no significant difference in the prevalence of infection between gender, height and weight adjusted for age, history of breastfeeding, mother's education, number of people per room, number of people per bed, smoking habit of the mother and children's history of antibiotic intake. A significant difference was found in the prevalence of H. pylori infection and H. pylori status of mother (p = 0.02; odds ratio (OR) 2.98; 95% confidence interval (CI): 1.19-7.46) that remained significant after adjustment for covariates in multivariate analysis (p = 0.012; OR 4.65; 95%CI: 1.39-15.58). CONCLUSIONS: This study shows that children living in low socioeconomic status and poor hygienic conditions are infected very early in childhood. It identifies age and H. pylori positive mother as independent risk factors for infection.  相似文献   
1000.
Recently the phenomenon of aspirin resistance has been object of several studies, but no data are available on the possible role of the haemorheologic parameters in affecting platelet function and resistance to antiplatelet agents. Aim of our study was to evaluate platelet function and haemorheology in patients with acute coronary syndromes (ACS), receiving double antiplatelet therapy with aspirin and clopidogrel. The study population included 301 (231M/70F; age: 66 +/- 13 yrs) consecutive adult patients admitted to the Coronary Care Unit of the Azienda Ospedaliero-Universitaria Careggi, with diagnosis of acute myocardial infarction or unstable angina. We assessed: whole blood viscosity (WBV) at shear rates of 0.512 s(-1) and 94.5 s(-1), plasma viscosity (PLV) at 94.5 s(-1) shear rate, erythrocyte deformability index (DI) and PFA-100 closure times with ADP (PFA/ADP) and epinephrine (PFA/EPI). We considered any PFA-100-EPI result < 203 sec (95th percentile of control distribution) to be indicative of aspirin resistance. 104/301 patients (34.5%) had PFA/EPI CTs in the reference range (group 1) whereas the remaining had values higher than 203 sec (group 2). WBV at 94.5 sec (-1) s.r. was similar in group 1 and 2 (WBV: 4.43 +/- 0.25 vs 4.45 +/- 0.61 mPa.sec, respectively). PLV and WBV at 0.512 sec (-1) s.r. were slightly higher, but not significantly, in group 1 than in group 2 (PLV: 1.47+/-0.13 vs 1.44 +/- 0.15 mPa.sec; p = 0.08 and WBV: 23.37 +/- 4.6 vs 22.54 +/- 3.90 mPa.sec; p = 0.07). DI was significantly lower in group 1 with respect to group 2 (4.05 +/- 2.93 vs 5.71 +/- 3.30, p < 0.0001). White blood count (WBC) was significantly higher in group 1 than in group 2 (11464 +/- 3504 vs 7867 +/- 2162, p < 0.0001). In conclusion, these results demonstrate that in patients with acute coronary syndromes the antiaggregant effect of aspirin is modulated not only by the direct action on platelets, but also by erythrocyte deformability and white blood cell count.  相似文献   
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