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1.
Basosquamous carcinoma of the skin is a rare malignancy with specific histopathological features of both basal cell carcinoma and squamous cell carcinoma. Some authors believe that basosquamous carcinoma is a variant of basal cell carcinoma, while others suggest that this tumour may behave more aggressively. We present a 44-year-old female patient who was diagnosed with a basosquamous carcinoma histopathologically. She had extensive ulcero-vegetative lesions, involving the anterior half of the scalp, the left orbit and the left side of the face. With this case we aim to emphasize the aggressive nature of basosquamous carcinoma and review the literature.  相似文献   
2.
We studied the risk of the development of acute myeloid leukemia (AML) during initial remission in 733 consecutive children with acute lymphoid leukemia (ALL) who were treated with intensive chemotherapy. This complication was identified according to standard morphologic and cytochemical criteria in 13 patients 1.2 to 6 years (median, 3.0) after the diagnosis of ALL. At three years of follow-up, the cumulative risk of secondary AML during the first bone marrow remission was 1.6 percent (95 percent confidence limits, 0.7 and 3.5 percent); at six years, it was 4.7 percent (2 and 10 percent). The development of secondary AML was much more likely among patients with a T-cell than a non-T-cell immunophenotype (cumulative risk, 19.1 percent [6 and 47 percent] at six years). Sequential cytogenetic studies in 10 patients revealed entirely different karyotypes in 9, suggesting the induction of a second neoplasm. In eight of these patients, the blast cells had abnormalities of the 11q23 chromosomal region, which has been associated with malignant transformation of a pluripotential stem cell. There was no evidence of loss of DNA from chromosome 5 or 7, a karyotypic change commonly observed in cases of AML secondary to treatment with alkylating agents, irradiation, or both. We conclude that there is a substantial risk of AML in patients who receive intensive treatment for ALL, especially in those with a T-cell immunophenotype, and that 11q23 chromosomal abnormalities may be important in the pathogenesis of this complication.  相似文献   
3.
4.
St Jude Total Therapy Study XIIIB for childhood acute lymphoblastic leukemia (ALL) incorporated more stringent risk classification, early intensification of intrathecal chemotherapy, reinduction treatment, and the addition of dexamethasone to postremission therapy to increase the proportion of event-free survivors without jeopardizing their quality of life. Cranial irradiation was reserved for the 12% of patients who had T-cell ALL and a presenting leukocyte count of 100 x 10(9)/L or more, or CNS-3 (5 or more leukocytes/microL with identifiable blast cells in an atraumatic sample or the presence of cranial nerve palsy) status. Among the 247 consecutive patients enrolled in the study, 117 were classified as having lower-risk leukemia and received mainly antimetabolite-based continuation therapy; the 130 cases with higher-risk leukemia received more intensive continuation chemotherapy with multiple drug pairs administered in weekly rotation. The 5-year event-free survival estimate was 80.8% +/- 2.6% (SE); the 8-year rate was 78.6% +/- 5.8%. The 5-year cumulative risk of an isolated central nervous system (CNS) relapse was 1.7% +/- 0.8%, and that of isolated plus combined CNS relapse was 3.0% +/- 1.1%. The 5-year cumulative risks of etoposide-related myeloid malignancies were 1.8% +/- 1.3% in the lower-risk patients who received a cumulative dose of 1.2 g/m(2) and 5.0% +/- 2.0% in the higher-risk patients who received a cumulative dose of up to 14.4 g/m(2) (P = .18). Independent adverse prognostic features included the presence of MLL-AF4 or BCR-ABL fusion gene and minimal residual leukemia of 0.01% or more at the end of the 6-week remission induction phase. Our results suggest the efficacy of early intensification of intrathecal chemotherapy and provide the basis for studies omitting cranial irradiation altogether.  相似文献   
5.
Cytogenetic and DNA flow cytometric analyses of leukemic cells from 2,184 children with newly diagnosed acute lymphoblastic leukemia (ALL) identified 27 cases (1.2%) that had a hypodiploid line with fewer than 45 chromosomes per cell. Had cytogenetic techniques been used alone, seven cases would have been missed, compared with five if only flow cytometry had been used. For comparative purposes, the 27 cases were divided into three groups: near-haploid (n = 10), hypodiploid 30-40 (n = 9), and hypodiploid 41-44 (n = 8). Blast cells from patients with near-haploid ALL lacked structural chromosomal abnormalities; showed nonrandom retention of two copies of chromosomes 8, 10, 14, 18, 21, and the sex chromosomes; and had a second leukemic line with exactly twice the number of chromosomes or DNA content. Karyotypic analysis of the hypodiploid 30-40 and hypodiploid 41-44 groups disclosed structural abnormalities in the stemline or sideline of most of the well-banded cases; those in the latter group were similar to findings in cases with 45 chromosomes. As in the near-haploid group, chromosome 21 and the sex chromosomes were preferentially retained in the hypodiploid 30-40 and 41-44 cases. Except for a slight excess of female patients in the near-haploid group and an older age at diagnosis in the hypodiploid 30-40 cases, there were no initial clinical features that distinguished these patients from the general ALL population. Despite intensive treatment and short follow-up, 17 of the 27 patients have relapsed. This study suggests that the poor treatment responsiveness of hypodiploid ALL is not limited to the more than 80% of the patients who have 45 chromosomes per leukemic cell and demonstrates that cytogenetic and flow cytometric analyses are complementary in the evaluation of children with ALL.  相似文献   
6.
Cytogenetic analysis of leukemic cells from 2,805 children with newly diagnosed acute lymphoblastic leukemia (ALL) identified 83 cases (3%) that had a stemline with at least one isochromosome. The i(9q) was present in 28 (1%), the i(17q) in 23 (0.8%), and the i(7q) in 23 (0.8%). Other isochromosomes--i(21q), i(6p), i(1q), i(8q), or i(Xq)--were found in only 12 cases (0.4%). The isochromosome cases were more likely than were other ALL cases to have a pre-B immunophenotype (38% v 25%, P = .02) and leukemic cell hyperdiploidy greater than 50 (37% v 24%, P = .02); five cases had both features. The i(9q) was associated with age greater than 10 years (P less than .05) and the pre-B immunophenotype (P = .05); both the i(17q) and i(7q) had high frequencies of hyperdiploidy greater than 50 (P less than .0001 and P = .05, respectively). The t(1;19)(q23;p13) was a common feature (23%) in cases with the i(9q), i(7q), i(6p), or i(1q). These findings establish the i(9q), i(17q), and i(7q) as nonrandom chromosomal abnormalities in ALL. The prognostic significance of the presence of isochromosome(s) remains to be determined.  相似文献   
7.
The aim of this study was to evaluate the acute effects of unilateral ankle plantar flexors static-stretching (SS) on the passive range of movement (ROM) of the stretched limb, surface electromyography (sEMG) and single-leg bounce drop jump (SBDJ) performance measures of the ipsilateral stretched and contralateral non-stretched lower limbs. Seventeen young men (24 ± 5 years) performed SBDJ before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch) unilateral ankle plantar flexor SS (6 sets of 45s/15s, 70-90% point of discomfort). SBDJ performance measures included jump height, impulse, time to reach peak force, contact time as well as the sEMG integral (IEMG) and pre-activation (IEMGpre-activation) of the gastrocnemius lateralis. Ankle dorsiflexion passive ROM increased in the stretched limb after the SS (pre-test: 21 ± 4° and post-test: 26.5 ± 5°, p < 0.001). Post-stretching decreases were observed with peak force (p = 0.029), IEMG (P<0.001), and IEMGpre-activation (p = 0.015) in the stretched limb; as well as impulse (p = 0.03), and jump height (p = 0.032) in the non-stretched limb. In conclusion, SS effectively increased passive ankle ROM of the stretched limb, and transiently (less than 10 minutes) decreased muscle peak force and pre-activation. The decrease of jump height and impulse for the non-stretched limb suggests a SS-induced central nervous system inhibitory effect.

Key points

  • When considering whether or not to SS prior to athletic activities, one must consider the potential positive effects of increased ankle dorsiflexion motion with the potential deleterious effects of power and muscle activity during a simple jumping task or as part of the rehabilitation process.
  • Since decreased jump performance measures can persist for 10 minutes in the stretched leg, the timing of SS prior to performance must be taken into consideration.
  • Athletes, fitness enthusiasts and therapists should also keep in mind that SS one limb has generalized effects upon contralateral limbs as well.
Key words: Athletic training, exercise performance, exercise training, crossover, cross-education  相似文献   
8.
9.

Objective

Decompressive hemicraniectomy (DC) and duroplasty after malignant brain infarction or traumatic brain injury is a common surgical procedure. Usually, preserved bone flaps are being reimplanted after resolution of brain swelling. Alloplast cranioplasties are seldom directly implanted due to the risk of wound healing disorders. While numerous studies deal with DC, little is known about the encountered problems of bone flap reimplantation. Thus, aim of the study was to identify surgery-associated complications after bone flap reimplantation.

Methods

We performed a retrospective chart analysis of patients that underwent DC and subsequent bone flap reimplantation between 2001 and 2011 at our institution. We registered demographic data, initial clinical diagnosis and surgery-associated complications.

Results

We identified 136 patients that underwent DC and subsequent reimplantation. Forty-one patients (30.1%) had early or late surgery-associated complications after bone flap reimplantation. Most often, bone flap resorption and postoperative wound infections were the underlying causes (73%, n = 30/41). Multivariate analysis identified age (p = 0.045; OR = 16.30), GOS prior to cranioplasty (p = 0.03; OR = 2.38) and nicotine abuse as a prognostic factor for surgery-associated complications (p = 0.043; OR = 4.02). Furthermore, patients with early cranioplasty had a better functional outcome than patients with late cranioplasty (p < 0.05).

Conclusions

Almost one-third of the patients that are operated on for bone flap reimplantation after DC suffer from surgery-associated complications. Most often, wound healing disorders as well as bone flap resorption lead to a second or even third operation with the need for artificial bone implantation. These results might raise the question, if subsequent operations can be avoided, if an artificial bone is initially chosen for cranioplasty.  相似文献   
10.
The purpose of this study was to analyze upper extremity and core muscle activation when performing push-ups with different suspension devices. Young fit male university students (n = 29) performed 3 push-ups each with 4 different suspension systems. Push-up speed was controlled using a metronome and testing order was randomized. Average amplitude of the electromyographic root mean square of Triceps Brachii, Upper Trapezius, Anterior Deltoid, Clavicular Pectoralis, Rectus Abdominis, Rectus Femoris, and Lumbar Erector Spinae was recorded. Electromyographic signals were normalized to the maximum voluntary isometric contraction (MVIC). Electromyographic data were analyzed with repeated-measures analysis of variance with a Bonferroni post hoc. Based upon global arithmetic mean of all muscles analyzed, the suspended push-up with a pulley system provided the greatest activity (37.76% of MVIC; p < 0.001). Individually, the suspended push-up with a pulley system also provided the greatest triceps brachii, upper trapezius, rectus femoris and erector lumbar spinae muscle activation. In contrast, more stable conditions seem more appropriate for pectoralis major and anterior deltoid muscles. Independent of the type of design, all suspension systems were especially effective training tools for reaching high levels of rectus abdominis activation.

Key Points

  • Compared with standard push-ups on the floor, suspended push-ups increase core muscle activation.
  • A one-anchor system with a pulley is the best option to increase TRICEP, TRAPS, LUMB and FEM muscle activity.
  • More stable conditions such as the standard push-up or a parallel band system provide greater increases in DELT and PEC muscle activation.
  • A suspended push-up is an effective method to achieve high muscle activity levels in the ABS.
Key words: EMG, unstable, core, trunk, exercise  相似文献   
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