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51.
Computed tomography (CT) of bone was carried out in 20 patients with breast cancer, all of whom had abnormal radionuclide uptake on skeletal scintigrams but normal conventional radiographs. Twenty-eight sites were examined and 13 showed metastases in 11 patients. Five of these patients had no evidence of extra-skeletal recurrent disease. Follow-up at eight of these sites showed healing, sclerosis or progression, all of which correlated well with clinical findings. CT showed benign causes of radionuclide accumulation in three patients (7 sites) but no abnormality in six patients (8 sites). None of these patients has subsequently developed bone metastases. CT is superior to conventional radiographs in the diagnosis of skeletal metastases and should be carried out when skeletal scintigraphy is positive and conventional examinations are normal.  相似文献   
52.
AIMS: The purpose of the present study was to compare the effectiveness of instruction to contract the pelvic floor muscles (PFM), the transversus abdominis (TrA), and the TrA + PFM visualized as displacement of the pelvic floor by ultrasound. MATERIALS AND METHODS: Twenty female physical therapists, mean age 41.1 years (range 26-56) participated in the study. A 3.5 MHz 35 mm curved linear array ultrasound transducer (Dornier Medtech) was placed in the mid-sagittal plane immediately suprapubically, angled at 15-30 degrees from the vertical depending on subcutaneous fat and anatomical variations, to image the pelvic floor. Six trials of three maneuvers in random order were performed: contraction of PFM, TrA, and TrA + PFM. RESULTS: In spite of correct contractions assessed by palpation and clinical observation, one subject demonstrated a downward movement of the pelvic floor during PFM contraction on ultrasound. Six subjects (30%) showed a downward movement during a TrA- contraction, and two during the combined TrA + PFM contraction. Instruction to contract PFM produced significantly greater mean displacement: 11.2 mm (95% CI 7.2-15.3) than TrA 4.3 mm (95% CI -0.2-8.8), P < 0.01, and combination: 8.5 mm (95% CI 5.2-12), P = 0.04. Hence, instruction of PFM contraction produced a 61.6% greater displacement of the pelvic floor in the correct direction than a TrA contraction. CONCLUSIONS: It is concluded that ultrasound is a more valid method than palpation and clinical observation to assess PFM function, and that instruction to contract the PFM produces a significantly more effective pelvic floor muscle contraction than instruction to perform a TrA contraction.  相似文献   
53.

BACKGROUND:

There are many methods available for coverage of both the volar and dorsal hand surfaces in traumatic injury. All of these surgical procedures allow for ample coverage of the defect, but have the major drawback of needing multiple donor sites. In the present report, a case of a complex crush injury to the hand in which both volar and dorsal surfaces received traumatic injury is presented. A bilobed groin flap pedicled on the superficial circumflex iliac artery was fashioned to cover the entire defect. Like many other described flaps, the bilobed groin flap resulted in a favourable functional and cosmetic result for the patient, but with the unique advantage of requiring a single donor site.

METHODS:

A bipedicled groin flap was raised from distal to proximal, and the flaps inset onto both the dorsal and volar hand defects.

RESULTS:

The patient regained adequate function of his hand, and was able to return to work full-time as a manual labourer.

CONCLUSION:

The bilobed groin flap appears to be a valuable option for covering complex hand injuries involving both the volar and dorsal surfaces of the hand.  相似文献   
54.
BACKGROUND: Until recently, there has been no practical alternative to the use of calcineurin inhibitors (CIs) as primary immunosuppressants in lung transplantation (LTx) and heart transplantation (HTx). Sirolimus (SRL) is a novel powerful immunosuppressant without renal toxicity, a common post-transplant problem associated with CI therapy. METHODS: SRL was used in 20 LTx and 5 HTx recipients >90 days post-transplant, where serious renal impairment was limiting CI dosing. Patients started on 2 to 5 mg/day orally at a median of 1,185 days post-transplant. Dosage adjustments were made according to trough levels, toxicity and perceived efficacy. With SRL initiation, 48% ceased CI therapy and the remainder decreased their dose substantively. RESULTS: After 30 days, 4 of 5 dialyzed patients ceased dialysis and 15 of 20 patients with an elevated serum creatinine (Cr) (mean Cr 0.29 mmol/liter) improved their Cr. The direction of change in Cr at 30 days predicted longer term Cr. The starting Cr did not predict the 30-day or long-term value. There were two bouts of acute and one bout of chronic rejection. There were 35 infectious complications in 16 patients and 24 episodes of potential SRL-related toxicity in 17 patients. These events generally responded to dose reduction or temporary cessation and were level-related. Fifteen recipients presently remain on the drug. None of the 7 deaths could be directly related to toxicity. CONCLUSION: SRL is a useful alternative immunosuppressant, allowing significant CI withdrawal in transplant recipients with renal impairment. Whether the resulting improvement in Cr can be maintained in the long term probably depends on the balance between the extent of acute and chronic renal damage.  相似文献   
55.
Background. A variety of rotary blood pumps are under development worldwide to serve as chronic ventricular assist devices (VADs). Historically VADs have been associated with thrombotic and thromboembolic complications, yet the ability to evaluate the thrombotic process in preclinical device testing has been limited.

Methods. We have developed and applied flow cytometric assays for activated platelets, platelet microaggregates, and platelet life span and consumption to calves implanted with an axial flow VAD and calves undergoing a sham surgical procedure.

Results. Surgical sham calves had significant increases in circulating activated platelets (p < 0.05) that resolved within 17 days, and no increases in circulating platelet microaggregates. Calves with uneventful VAD implant periods had early transient elevations in platelet microaggregates and prolonged elevations in activated platelets that did not recover to preoperative values during the study. Daily platelet consumption in VAD implanted calves was increased by 20% ± 3%. Calves with thrombotic deposition within the VAD and elevated thromboembolism observed at autopsy experienced increases in circulating activated platelets and microaggregates at the end of the implant period when VAD flow decreased.

Conclusions. This study demonstrates the ability of flow cytometry-based platelet assays to differentiate VAD implant operations from VAD support, and suggests differences that exist between uneventful VAD support and support with complications. These techniques should have value in evaluating other cardiovascular devices undergoing preclinical testing and provide insight into the temporal impact of these devices on the hemostatic system.  相似文献   

56.
Sperm maturation in the epididymis: a new look at an old problem   总被引:4,自引:0,他引:4  
The osmotic challenges facing maturing spermatozoa and their responses to them are discussed in relation to the concept of sperm maturation, defined as the increased ability of more distally recovered epididymal spermatozoa to fertilize eggs when inseminated into the female tract. One explanation could be that the more distal cells are better able to regulate their volume, and reach the oviducts, as a consequence of uptake of epididymal osmolytes. Increased motility, zona binding and oolemma fusion capacities are also acquired within the epididymis and are necessary for those cells that finally arrive at the site of fertilization. (Asian J Androl 2007 July; 9: 533-539)  相似文献   
57.
Although many studies have analyzed the success rates of closed reduction and spica casting for the treatment of developmental dysplasia of the hip (DDH) in children, the definition of success for this procedure is not standardized in the literature. We retrospectively reviewed our experience with closed reduction for treatment of DDH in 30 children (35 hips) over an 8-year period to determine the success rates of this procedure on the basis of how success is defined. In only 1 patient (2 hips, 6%) were the hips unable to be concentrically reduced with sufficient stability at the time of closed reduction. In 10 (30%) of the other 33 hips, the acetabulum failed to develop sufficiently after closed reduction, and a secondary surgery was required a mean of 22 months after cast removal. Four (12%) of the 33 hips developed radiographic evidence of avascular necrosis. Therefore, the success rate of closed reduction for DDH varies markedly depending on how success is defined.  相似文献   
58.
OBJECTIVE. To examine how the use of additional treatment for prostate cancer differs as a function of the initial therapy (radical prostatectomy [RP], radiation therapy [RT], androgen deprivation therapy [ADT], or watchful waiting [WW]) for men with non-metastatic prostate cancer. MATERIAL AND METHODS. A dataset was created that combined information from the Surveillance, Epidemiology, and End Results program and Medicare claims for hospital and physician services. To identify patients receiving additional cancer treatment, we searched the claims for the presence of RP, RT (palliative radiation not included), or ADT. RESULTS. The study population consisted of 12 711 patients: as initial treatment, 3940 (31.0%) had RP, 3950 (31.1%) RT, 1209 (9.5%) ADT, and 3612 (28.4%) WW. The RP group had a less favorable distribution of tumor differentiation than the RT group. Only 54.6% of men who had initial RP had localized cancer. In men who had initial RP, 8.1% had RT and 12.4% ADT during the follow-up period, which was 6-66 months after the initial therapy ended. Among patients who had initial RT or WW, 22.8% and 22.1%, respectively had ADT during the follow-up period. CONCLUSION. Older American men with prostate cancer who are initially treated with RT or simply observed (WW) are more likely than men who undergo RP to receive ADT as a follow-up treatment.  相似文献   
59.
To determine whether an improvement in skin lesions as a result of PUVA therapy may be correlated with changes in cytokine patterns, RT-PCR amplification was used to compare the levels of IL-2, IL-6, IL-8, IL-10, TNF-α and IFN-γ cytokine mRNA expression in serial biopsies from three chronic plaque psoriatic patients. In each case, 3-mm punch biopsies were taken from lesional skin before and during 2–28 days of treatment with PUVA. Total mRNA was extracted from each biopsy, cDNA synthesized, and then amplified by 35 cycles of PCR using cytokine-specific primers. The specificity of the PCR products was confirmed by the Southern blot technique. Substantial levels of specific mRNA for each of the cytokines studied was present in the lesions prior to treatment. In two of the three patients who responded well to PUVA, a reduction in all the cytokines including IL-10 was observed compared with baseline levels. In contrast, PUVA proved to be ineffective in clearing the psoriasis of the third patient whose skin lesions worsened during the course of treatment. This was accompanied by an increase in IFN-γ but not of the other cytokines investigated, above the pretreatment level. This study showed an association between PUVA-induced resolution and decreases in the levels of various cytokines highly expressed in psoriatic lesions. Received:14 August 1995  相似文献   
60.
PURPOSE: CNTF is a neuroprotective agent for retinal degenerations that can cause reduced electroretinogram (ERG) amplitudes. The goal of the present study was to determine the effects of intraocular delivery of CNTF on normal rat visual function. METHODS: Full-field scotopic and photopic ERG amplitudes and spatial frequency thresholds of the optokinetic response (OKR) of adult Long-Evans rats were measured before and after intravitreous injection of CNTF or subretinal delivery of adenoassociated virus-vectored CNTF (AAV-CNTF) into one eye. Visual acuity was also measured by using the Visual Water Task in AAV-CNTF-injected animals. Multiunit luminance thresholds were recorded in the superior colliculus after CNTF injection, and the eyes were examined histologically. RESULTS: In eyes injected with a high dose of CNTF, ERG amplitudes and OKR thresholds measured through CNTF-injected eyes were decreased by 45% to 70% within 6 days after injection. ERG amplitudes had begun to recover by 21 days, whereas OKR thresholds only began to recover after 56 days. Neither OKR thresholds nor ERG amplitudes fully recovered until 90 to 100 days. When measured in the superior colliculus at 2 weeks after CNTF injection, luminance thresholds were elevated by 0.35 log units. In AAV-CNTF-injected eyes, OKR thresholds, and visual acuity were reduced by approximately 50% for at least 6 months, and scotopic and photopic ERG b-waves were reduced by 30% to 50%. Photoreceptor loss occurred in the injected regions in some of the eyes. By contrast, comparison of dose-response analysis with a dose-response study of light damage strongly suggests that therapeutic doses of CNTF exist that do not suppress ERG responses. CONCLUSIONS: Intraocular delivery of CNTF, which preserves photoreceptors in animal models of retinal degeneration, impairs visual function in normal rats at very high doses, but not at lower doses that still provide protection from constant light damage.  相似文献   
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