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21.
Sixty-one patients with histologically proven disorders of the prostate [prostatic carcinoma (PC), 41; benign prostatic hyperplasia (BPH), 9; PC and BPH, 11] underwent magnetic resonance imaging at 1.5 T. Using single [spin echo (SE) 400/30] and dual (SE 1,600/30, 90) SE sequences, multislice contiguous scans were obtained in transverse, sagittal, and coronal planes through the prostate. In 27 patients (PC 14, BPH 6, PC and BPH 7) multiecho sequences with eight echoes (SE 1,600/30, 60, 90, 120, 150, 180, 210, 240) were acquired and T2 images were calculated in the planes with best depiction of circumscribed prostatic pathology. In these patients the Bhattacharyya coefficient, a quantitative criterion for the discrimination between normal and pathological tissue, derived by means of mathematical decision theory, was applied. This analysis showed the best discrimination between PC and normal prostate with echo time (TE) 90 and 120 ms [error rate (ER) for confusing these tissues 20-30%]. There was no significant difference between the signal intensities of PC and BPH at any parameter setting, but PC could be discriminated from the compressed peripheral glandular regions that often accompany BPH [minimal ER (20-30%) at TE 90 and 120 ms]. This distinction is of clinical value, since PC usually arises in the periphery of the prostate. Calculated T2 images did not show advantages for the detection of PC.  相似文献   
22.
IntroductionBurkitt lymphoma (BL) originating in the skin and soft tissue is very rare. To our knowledge, this case of primary sporadic BL presenting as an isolated chest wall mass arising from the soft tissue in an adult may be the first report.Case ReportA previously healthy 33-year-old Caucasian man presented with a 1-month history of a painful lump over the left breast that he initially noticed as a small “pimple-like” lesion in the area. After a week, the skin lesion became larger, erythematous, and painful. At a local hospital, he underwent an incision and drainage procedure for a presumed chest wall abscess. Several days after debridement, a similar lump recurred around the incised area, which rapidly grew in size. He also started experiencing fever and chills for which he was readmitted with a diagnosis of necrotizing chest wall infection. A second debridement with excisional biopsy of the chest wall revealed atypical lymphoid cells, prompting transfer to our institution. Upon transfer, a large, gaping, erythematous and indurated wound with indistinct, thickened borders and extensive edema and necrosis of subcutaneous tissue and musculature of almost the entire left chest wall was noted. No palpable peripheral lymphadenopathy or organomegaly were observed. He underwent minimal debridement and partial excision. The histopathology revealed atypical lymphocytes with prominent nucleoli, deeply basophilic cytoplasm, and abundant lipid vacuoles in a “starry-sky” pattern. The lymphoid population was CD-20 and CD-10 positive, negative for CD-5 and BCL-2, nearly 100% Ki-67 positive, and indeterminate for light chain restriction. Molecular cytogenetic analysis revealed fusion signals with IgH/Myc t(8;14) dual fusion probe, supporting the diagnosis of BL. Staging positron emission tomography (PET)/computed tomography (CT) scan showed a large subcutaneous defect of the left hemithorax involving the dermis, subcutaneous tissue, and musculature, measuring 19.3 × 13.9 × 31.0 cm, with maximal SUV of 9.8 and an average of 6.2. No additional involved sites were seen. The bone marrow biopsy showed minimal involvement by BL and abnormal hybridization pattern for IgH/Myc t(8;14) and Epstein-Barr virus, while the peripheral blood and cerebrospinal fluid showed no involvement. HIV and hepatitis serologies were negative. Three days after surgery, chemotherapy with granulocyte colony-stimulating factor (G-CSF) support was initiated for high-risk disease. He received CODOX-M (intravenous cyclophosphamide, doxorubicin, vincristine, methotrexate; intrathecal cytarabine, methotrexate) as cycle 1 followed by IVAC (intravenous ifosfamide, etoposide, cytarabine; intrathecal methotrexate) with rituximab as cycle 2. He developed tumor lysis without end-organ damage. However, a few days after completion of cycle 2, he developed neutropenic fever and pneumonia, and died in septic shock.DiscussionPrimary chest wall tumors are uncommon. Approximately 50% are malignant, and chest wall lymphoma accounts for < 2%, with extranodal diffuse large B-cell lymphoma being the most common. Primary skin and soft tissue involvement of the chest wall in the absence of detectable lymphadenopathy and visceral disease in an adult by BL has not yet been reported. While there are isolated reports of skin and soft tissue involvement, they were in the setting of immunodeficiency state and were felt to be the result of either iatrogenic tumor seeding after nodal biopsies or local tumor invasion as a manifestation of recurrent disease. This patient's clinical presentation began with the development of an isolated rapidly enlarging chest wall mass that progressed despite surgical debridements.ConclusionThis case illustrates a primary sporadic BL originating in skin and soft tissue in an adult. Whether this case represents a BL that began in the skin and soft tissue and spread to the bone marrow, or began in the bone marrow and spread to the chest wall cannot be determined. The role of tumor debulking procedure is uncertain, although aggressive chemoimmunotherapy with central nervous system (CNS) prophylaxis is warranted as with other BL presentations.  相似文献   
23.
BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients.  相似文献   
24.
25.
Bone marrow aspirates from patients with acute agranulocytosis or a marked left shift in myeloid maturation can mimic acute leukemia, particularly acute hypergranular promyelocytic leukemia. Bone marrow aspirates from 16 cases of apparent acute promyelocytic leukemia, 4 cases of acute agranulocytosis, and 1 case of a marked myeloid left shift were studied for the presence or absence of differentiating features. Normal or reactive promyelocytes were characterized by prominent paranuclear clear Golgi zones, whereas promyelocytes from true leukemic cases all had heavy azurophilic granules dispersed diffusely throughout the cytoplasm. Prominent Golgi zones in promyelocytes were associated only with benign myeloid conditions and were not observed in acute promyelocytic leukemia. The presence of prominent clear Golgi zones in promyelocytes is an important feature assisting in the distinction between leukemic and benign promyelocytes.  相似文献   
26.
BACKGROUND: Metabolic evaluation in recurrent idiopathic calcium renal stone-formers (RCSF) was analysed with respect to the following questions: (1) do three 24-h urines provide more diagnostic accuracy in the metabolic evaluation of RCSF than 1 or 2 urines?; (2) does time after stone event influence the diagnostic yield?; (3) is urine composition at weekends different from that at mid-week?; (4) what are the prevalences of the most important risk factors (RF) of idiopathic calcium nephrolithiasis, i.e. low volume (LV), hypercalciuria (HC), hyperoxaluria (HO), hyperuricosuria (HU), hypocitraturia (Hypo-Cit), and hypomagnesiuria (Hypo-Mg)?; and (5) do male RCSF differ from females with respect to urinary RFs? METHODS: Seventy-five RCSF (59 men, 16 women) collected three 24-h urines (U1-3) while on free-choice diet. To account for possible variations in lifestyle and diet, U1 and U3 had to be collected midweek and U2 at a weekend. RESULTS: When considering all three urines together (U1 + U2 + U3), the number of RF abnormalities/patient was 2.8 +/- 0.1, higher than numbers of any combination of two urines or of any single urine (P = 0.0001 for all comparisons). The number of RF abnormalities also rose with time after stone event, from 0.8 +/- 0.1 (range 0-4) in U1 to 1.1 +/- 0.1 (range 0- 4) in U3 (P = 0.011 vs U1). Whereas all other RF did not change between collections, urine volume was lower in U2 (1793 +/- 90 ml) than in U1 (2071 +/- 97 ml, P = 0.0001 vs U2) and U3 (1946 +/- 97 ml, P = 0.046 vs U2). At least 1 abnormality was found in 85.3% of all RCSF, and multiple abnormalities occurred in 47%. The most frequent RF was HC (39%), followed by HO and LV (32% each), Hypo-Cit (29%), HU (23%) and Hypo-Mg (19%). Males more often had Hypo-Cit (P < 0.001) and Hypo-Mg (P < 0.01) than females, whereas HO was more frequent in female RCSF (P < 0.025 vs males). CONCLUSIONS: Diagnostic accuracy of metabolic evaluation in RCSF increases both with the number of urines collected and the time passing after a stone event. Urines collected at weekends differ from those of the week only by their lower volumes. Abnormalities of RF for calcium nephrolithiasis can be detected in 85.3% of RCSF, and HC is the most common RF both in male and female RCSF.   相似文献   
27.
This report used the framework of a large European study to investigate the outcome of patients with and without an HLA-identical sibling donor on an intention-to-treat basis. After a common remission-induction and consolidation course, patients with an HLA-identical sibling donor were scheduled for allogeneic transplantation and patients lacking a donor for autologous transplantation. In all, 159 patients alive at 8 weeks from the start of treatment were included in the present analysis. In total, 52 patients had a donor, 65 patients did not have a donor and in 42 patients the availability of a donor was not assessed. Out of 52 patients, 36 (69%) with a donor underwent allogeneic transplantation (28 in CR1). Out of 65 patients, 33 (49%) received an autograft (27 in CR1). The actuarial survival rates at 4 years were 33.3% (s.e. = 6.7%) for patients with a donor and 39.0% (s.e. = 6.5%) for patients without a donor (P = 0.18). Event-free survival rates were 23.1% (s.e. = 6.2%) and 21.5% (s.e. = 5.3%), respectively (P = 0.66). Correction for alternative donor transplants did not substantially alter the survival of the group without a donor. Also, the survival in the various cytogenetic risk groups was not significantly different when comparing the donor vs the no-donor group. This analysis shows that patients with high-risk myelodysplastic syndrome and secondary acute myeloid leukemia may benefit from both allogeneic and autologous transplantation. We were unable to demonstrate a survival advantage for patients with a donor compared to patients without a donor.  相似文献   
28.
The shear modulus of the vocal fold is an essential parameter required to enhance our understanding of how the vocal fold operates, to develop mathematical models of phonatation, and to provide benchmarks to quantify the effectiveness of surgical procedures. The authors announced the successful deployment of an instrument to measure vocal fold elasticity in vivo last year, and now present the data taken from eight patients in vivo. The shear modulus was measured at the mid-membranous point, in a transverse direction with respect to the axis drawn between the anterior commissure and vocal process. The range of mean shear modulus results is 701–2,225 Pa, with a mean value of 1,371 Pa.  相似文献   
29.
Laparoscopic colposuspension is one of many new operations for treating female urinary stress incontinence. With initially reported success rates similar to those of the traditional open procedure, it appears to combine the advantages of laparoscopy (such as minimal invasiveness and quicker return to normal activities) with the effectiveness of the standard procedure. Different methods and approaches are used, but endoscopic suture techniques remain difficult and time-consuming. The use of endostapling devices for fixation of alloplastic material has been a tempting alternative. We present a case during which laparoscopic colposuspension was performed using staples and mesh. Incontinence did not improve, and the patient suffered severe chronic pain for 18 months postoperatively. Removal of the alloplastic material and traditional abdominal resuspension led to complete cure.  相似文献   
30.
Xenopus laevis oocytes have been used extensively during the past decade to express and study neurotransmitter receptors of various origins and subunit composition and also to express and study receptors altered by site-specific mutations. Interpretations of the effects of structural differences on receptor mechanisms were, however, hampered by a lack of rapid chemical reaction techniques suitable for use with oocytes. Here we describe flow and photolysis techniques, with 2-ms and 100-μs time resolution, respectively, for studying neurotransmitter receptors in giant (≈20-μm diameter) patches of oocyte membranes, using muscle and neuronal acetylcholine receptors as examples. With these techniques, we find that the muscle receptor in BC3H1 cells and the same receptor expressed in oocytes have comparable kinetic properties. This finding is in contrast to previous studies and raises questions regarding the interpretations of the many studies of receptors expressed in oocytes in which an insufficient time resolution was available. The results obtained indicate that the rapid reaction techniques described here, in conjunction with the oocyte expression system, will be useful in answering many outstanding questions regarding the structure and function of diverse neurotransmitter receptors.  相似文献   
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