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11.
Angina of rest and angina of effort may occur under a great variety of circumstances, but in the vast majority of cases they precede or follow myocardial infarction. In syphilitic aortitis and diseases other than those which lead to myocardial anorexia by direct involvement of the coronary arteries, angina pectoris is, by comparison, infrequent.Angina pectoris is usually more severe when it precedes, than when it follows, infarction; and angina of rest is very much more common before, than after, infarction has occurred, particularly if we exclude from this category the pains separated by short intervals that sometimes accompany the crisis. When anginal pain following infarction is not related to exertion, it is often due to other precipitating factors and the diagnosis of angina of rest, if this is defined as spontaneous anginal pain, is difficult.Angina of effort, which displays a rapid increase in severity and requires less and less effort to induce it, suggests that infarction is imminent. After infarction, the absence of angina of effort or a progressive decrease in its severity is a favorable omen. In such cases, we believe that a gradual increase in the patient's physical activity is beneficial.  相似文献   
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Balance and walking are fundamental to support common daily activities. Relatively accurate characterizations of normal and impaired gait features were attained at the kinematic and muscular levels. Conversely, the neural processes underlying gait dynamics still need to be elucidated. To shed light on gait‐related modulations of neural activity, we collected high‐density electroencephalography (hdEEG) signals and ankle acceleration data in young healthy participants during treadmill walking. We used the ankle acceleration data to segment each gait cycle in four phases: initial double support, right leg swing, final double support, left leg swing. Then, we processed hdEEG signals to extract neural oscillations in alpha, beta, and gamma bands, and examined event‐related desynchronization/synchronization (ERD/ERS) across gait phases. Our results showed that ERD/ERS modulations for alpha, beta, and gamma bands were strongest in the primary sensorimotor cortex (M1), but were also found in premotor cortex, thalamus and cerebellum. We observed a modulation of neural oscillations across gait phases in M1 and cerebellum, and an interaction between frequency band and gait phase in premotor cortex and thalamus. Furthermore, an ERD/ERS lateralization effect was present in M1 for the alpha and beta bands, and in the cerebellum for the beta and gamma bands. Overall, our findings demonstrate that an electrophysiological source imaging approach based on hdEEG can be used to investigate dynamic neural processes of gait control. Future work on the development of mobile hdEEG‐based brain–body imaging platforms may enable overground walking investigations, with potential applications in the study of gait disorders.  相似文献   
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Background

Pancreaticoduodenectomy for trauma (PDT) is a rare procedure, reserved for severe pancreaticoduodenal injuries. Using the National Trauma Data Bank (NTDB), our aim was to compare outcomes of PDT patients to similarly injured patients who did not undergo a PDT.

Methods

Patients with pancreatic or duodenal injuries treated with PDT (ICD-9-CM 52.7) were identified in the NTDB 2008–2010 Research Data Sets. We excluded those who underwent delayed PDT (>4 days). The PDT group (n = 39) was compared to patients with severe combined pancreaticoduodenal injuries (grade 4 or 5) who did not undergo PDT (non-PDT group, n = 38). Patients who died in the emergency department or did not undergo a laparotomy were excluded. Our primary outcome was death. Secondary outcomes were intensive care unit length of stay (LOS), hospital LOS, and total ventilator days. A multivariate model was used to determine predictors of in-hospital mortality within each group and in the overall cohort.

Results

The non-PDT group had a significantly lower systolic blood pressure and Glasgow Coma Scale values at baseline and more severe duodenal, pancreatic, and liver injuries. There were no significant differences in outcomes between the two groups. The Injury Severity Score was the only independent predictor of mortality among PDT patients [odds ratio (OR) 1.12, 95 % confidence interval (CI) 1.01–1.24] and in the entire cohort (OR 1.06, 95 % CI 1.01–1.12). The operative technique did not influence any of the outcomes.

Conclusions

Compared to non-PDT, PDT did not result in improved outcomes despite a lower physiologic burden among PDT patients. More conservative procedures for high-grade injuries of the pancreaticoduodenal complex may be appropriate.  相似文献   
15.
A 29-year-old man was admitted to the Department of Urology of the University of Padova with a diagnosis of prostatic adenocarcinoma. Cystourethrography showed a prostatic urethral obstruction, and CT scan demonstrated a low pelvic solid mass involving the prostate and the seminal vescicle. A radical prostatectomy was performed, and the prostate was found to be widely infiltrated by a neoplasia formed by tubules, papillary structures, and solid cords of cuboidal or flat elements, each having indistinct borders and scant cytoplasm, in a myxoid or fibrous stroma. "Schiller-Duval-like," PAS-diastase-resistant and alfa-fetoprotein hyaline bodies were present. An endodermal sinus (yolk-sac) tumor was diagnosed. There was infiltration of the periurethral prostatic ducts, prostatic urethra, and seminal vesicles and single lymph node metastasis. Testicular echotomography was negative. In spite of aggressive surgery and chemotherapy, the patient died 10 months after diagnosis. This is the third case in the literature after those presented by Benson and Michel.  相似文献   
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BACKGROUND: Changes in intestinal vascular capacitance during acute volume loading and hemorrhage have not been described. OBJECTIVES: To determine the effects of volume loading and hemorrhage on the intestinal vascular pressure-volume relationship and cardiac output. PATIENTS AND METHODS: In 11 alpha-chloralose-anesthetized dogs, a pneumatic portal venous constrictor and catheter were positioned to increase and measure portal venous pressure (Ppv), respectively. Relative changes in intestinal blood volume (IBV) were determined by blood-pool scintigraphy and expressed as the percentage change from control values (taken as 100%). Ppv-IBV relationships were constructed by graded portal vein constriction. RESULTS: IBV and cardiac output increased by 60 6% and 178 48%, respectively, and Ppv increased from 5.8 0.9 mmHg to 13.2 1.8 mmHg after initial volume loading (40 mL/kg of an isotonic glucose-saline solution over 7 min). IBV gradually decreased and reached near-control values after 75 min. In seven dogs, hemorrhage (sufficient to decrease mean aortic pressure by 56 4%) decreased IBV and cardiac output to 88 4% and 52 3% of control values, respectively, and Ppv decreased to 3.2 0.8 mmHg. CONCLUSIONS: A sigmoid function curve defined the relationship between cardiac output and IBV. Cardiac output remained constant over a wide range (between approximately 95% and 135% of control IBV). Outside this range, insufficient dilation or constriction resulted in a marked increase or decrease in venous pressures and cardiac output. These data indicate that vasculature capacitance modulates cardiac output during acute volume loading and hemorrhage, thereby maintaining cardiac output relatively constant over a wide range of total vascular blood volume.  相似文献   
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This study examined narrative representations of parents and of self, as well as child behavior during the assessment, in maltreated (N = 56) and demographically comparable non-maltreated (N = 37) pre-school-aged children in a one-year longitudinal study. Maltreated children evidenced more negative representations of parents and of self at Time 2, including the juxtaposition of both a negative and a grandiose self. Over time there was a marginal interaction such that maltreated children portrayed fewer disciplining parent representations and nonmaltreated children portrayed more. Also over time, maltreated children portrayed marginally more grandiose self-representations and nonmaltreated children fewer. Furthermore, maltreated children demonstrated less responsivity to the examiner over time and nonmaltreated children demonstrated more. The deleterious effects of maltreatment on representations of self and of others, especially as development proceeds, are discussed, and the importance of providing attachment-informed intervention prior to the consolidation of these negative representations is highlighted.  相似文献   
20.
The study objectives were to characterize the morphology of the parasitic forms and describe the prevalence and intensity of Haemogregarina spp. in a population of the turtle Podocnemis unifilis as well as to examine the relationships between parasitism and turtle variables such as gender, size, and weight. Samples were taken in the Tapajós and Jamanxim rivers, Itaituba, Pará state, Brazil. Blood was collected from the tail vein of 72 P. unifilis specimens, including 35 males, 36 females, and one unsexed juvenile. The prevalence of Haemogregarina spp. was 98 % (n?=?71). The mean parasite intensity of Haemogregarina spp. was 118 (1–582) parasites/2000 blood cells (6 %). There was no significant difference in the mean parasite intensity between male (137.68?±?121.8, n?=?35) and female turtles (101.42?±?123.59, n?=?35). There was no relationship between parasite intensity and carapace length. Although the relationship between parasite intensity and host body weight was significant, the relationship was weak. This is the first study on Haemogregarina parasitism with a relatively high number of turtles in Brazil.  相似文献   
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