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101.
102.
Nerve transection is commonly followed by the development of neuroma at the proximal stump. It can be very painful especially
at exposed sites. It may arise spontaneously or after mechanical irritation. Neuroma and its high recurrence rate might be
resisting problems to treat. Various treatment modalities for neuroma and its recurrence have been proposed, but none has
provided satisfactory results. The present study was conducted to evaluate the neodymium:yttrium aluminum garnet (Nd:YAG)
laser (1,064 nm) nerve transection technique for prevention of neuroma formation. There were 48 facial nerves out of 24 Rex
rabbits divided into two equal groups. The 24 left-sided facial nerves at group A were subjected to Nd:YAG laser for nerve
transection, while the 24 right-sided facial nerves at group B were subjected to scalpel nerve transection. The results were
grossly and histopathologically evaluated. Grossly, laser-transected nerves showed an infrequent incidence of neuroma formation.
Histopathologically, laser-transected nerves showed photothermal degenerative changes of the axons and myelin sheaths with
intact perineurium and endoneurium. No Schwann cell hyperactivity could also be elicited among laser-transected nerves. Nd:YAG
laser was found to be an effective tool that could be applied, whenever it is possible, for division of major nerves to prevent
the formation of the subsequent stump neuroma. Moreover, this technique should be considered during treatment of well-established
neuroma to prevent the challenging reported high incidence of recurrence. 相似文献
103.
The objective of this study was to observe the dose-response effects of testosterone (T) treatment on symptoms of sexual dysfunction and the metabolic syndrome. Two cohorts of elderly men with late-onset hypogonadism were followed over 9 months. Group 1, consisting of 28 men (mean age, 61 years; mean T level, 2.07 +/- 0.50 ng/mL), received long-acting T undecanoate (TU; 1000 mg); group 2, composed of 27 men (mean age, 60 years; mean T level, 2.24 +/- 0.41 ng/mL), received T gel (50 mg/day) for 9 months. In patients treated with T gel, plasma T levels rose from 2.24 +/- 0.41 to 2.95 +/- 0.52 (statistically significant) at 3 months, 3.49 +/- 0.89 (statistically significant) at 6 months, and 3.80 +/- 0.73 ng/mL at 9 months (T level at 6 months was compared with T level at 3 months). With TU, plasma T levels rose from 2.08 +/- 0.56 to 4.81 +/- 0.83 (statistically significant) at 3 months, 5.29 +/- 0.91 at 6 months, and 5.40 +/- 0.77 ng/mL at 9 months. With TU, the plasma T levels were statistically significantly higher than with T gel With TU, there was a greater improvement in sexual symptoms and in symptoms of the metabolic syndrome. With both treatments, changes in waist circumference correlated with changes in total, low-density, and high-density lipoprotein cholesterol. Parameters of safety were not different between the 2 treatments. T administration had a beneficial effect on sexual dysfunction and symptoms of the metabolic syndrome in elderly men. The higher plasma levels of T generated with TU than with T gel were clearly more effective, indicating that there is a T dose-effect relationship. 相似文献
104.
Bone reinnervation after fracture: a study in the rat. 总被引:11,自引:0,他引:11
J Li T Ahmad M Spetea M Ahmed A Kreicbergs 《Journal of bone and mineral research》2001,16(8):1505-1510
Reinnervation after tibial fracture in the rat was studied by analyzing the occurrence of growth-associated protein 43 (GAP-43), a marker for regenerating nerve fibers, and protein gene product 9.5 (PGP-9.5), a marker for mature nerve fibers, by immunohistochemistry. At 3 days postfracture, GAP-43--immunoreactive nerve fibers were first observed in the fracture hematoma and periosteum. At 7 days postfracture, abundant sprouting of GAP-43--positive fibers was seen in the callus, hyperplastic periosteum, and edge of fibrocartilage. In the latter region, the nerve fibers were nonvascular, showing dense ramifications and terminal sprouting close to chondroid cells. At 14 days and 21 days postfracture, many GAP-43--positive fibers were still sprouting into the fibrocartilage and new woven bone. Fine varicose GAP-43--positive fibers also were present in the bone marrow. In contrast to GAP-43, PGP-9.5-positive nerve fibers were observed only occasionally at 3 days postfracture but gradually increased in number from day 14 to 21. Our study shows that intense nerve regeneration occurs in early fracture healing partly unrelated to neovascularization. Considering that neuronal mediators have been shown to participate in local bone formation and resorption, the nerve regeneration observed may prove to be essential for delivery of neuronal mediators required for normal callus formation and/or neovascularization. 相似文献
105.
Changes in motion characteristics, plasma membrane integrity, and acrosome morphology during cryopreservation of buffalo spermatozoa 总被引:2,自引:0,他引:2
Motion characteristics, plasma membrane integrity, and acrosome morphology of buffalo spermatozoa after different stages of cryopreservation (ie, dilution, cooling to 4 degrees C, equilibration at 4 degrees C, and freezing and thawing) were examined. Semen ejaculates from 4 buffalo bulls were pooled (n = 5), diluted in tris-citric acid extender, cooled to 4 degrees C over 2 hours, equilibrated at 4 degrees C for 4 hours, dispensed into 0.5-mL straws, and frozen in a programmable cell freezer before plunging into liquid nitrogen. Frozen semen was thawed at 37 degrees C for 15 seconds. After completion of each stage, sperm motion characteristics, plasma membrane integrity, and acrosomal morphology were determined using computer-assisted semen analysis, hypo-osmotic swelling assay, and phase-contrast microscopy, respectively. Data were presented as mean +/- standard error of the mean. Visual and computerized motility did not differ due to dilution, cooling, or equilibration (77.3% +/- 2.3% and 90.5% +/- 1.2%, respectively), but was reduced (P < .05) after freezing and thawing (53.0% +/- 4.6% and 48.6% +/- 6.5%, respectively). Linear motility of spermatozoa was lower (P < .05) after dilution or equilibration (56.2% +/- 2.4%) than after cooling or freezing and thawing (79.6% +/- 1.4%). Sperm curvilinear velocity was reduced (P < .05) from 112.4 +/- 5.3 microm/sec after dilution to 96.0 +/- 5.8 microm/s after cooling, and from 87.6 +/- 4.1 microm/s after equilibration to 69.4 +/- 2.0 microm/s after freezing and thawing. Sperm lateral head displacement differed (P < .05) after each stage (ie, dilution, 3.9 +/- 0.2 microm; cooling, 2.3 +/- 0.2 microm; equilibration, 3.1 +/- 0.3 microm; and freezing and thawing, 1.7 +/- 0.2 microm). Spermatozoa with intact plasma membranes were 80.2% +/- 3.9% after dilution, reduced (P < .05) to 60.4% +/- 5.6% after equilibration, and then to 32.6% +/- 3.8% after freezing and thawing. The percentage of spermatozoa with normal acrosomes remained higher after dilution, cooling, or equilibration (73.2% +/- 2.4%) than after freezing and thawing (61.8% +/- 2.4%; P < .05). In conclusion, the maximal damage to the motility apparatus, plasma membrane, and acrosomal cap of buffalo spermatozoa occurs during freezing and thawing followed by equilibration. 相似文献
106.
Faried A Kimura H Faried LS Usman N Miyazaki T Kato H Yazawa S Kuwano H 《Annals of surgical oncology》2007,14(2):960-967
Background Tumor markers whose antigenic determinants have been demonstrated to consist of carbohydrates are probably one of the most
extensive tools that have been used in routine cancer diagnosis. In this study, the relevance of carbohydrate antigen expression
profile was examined in esophageal squamous cell carcinoma together with prognosis in 130 patients.
Methods The expression of carbohydrate antigens was estimated immunohistochemically by anti–sialyl Lewis a (sialyl Lea) and anti–sialyl Lewis x (sialyl Lex) monoclonal antibodies, and correlation between their staining and clinicopathological status was examined. In addition,
the correlation of both carbohydrate antigens expression was evaluated with microvessel density (MVD).
Results Expressions of sialyl Lewis antigens and MVD were associated with several clinicopathological features that reflect the tumor
aggressiveness in esophageal cancer. The 5-year survival rate of patients was found to be associated with expression of sialyl
Lea and sialyl Lex antigens and with MVD; thus, all of them were revealed to be independent prognostic factors.
Conclusions Combination of these factors offered a better prediction of prognosis of esophageal squamous cell carcinoma. Further, carbohydrate
antigens represent a promising target for therapeutic approaches against the disease. 相似文献
107.
Ahmad M 《International urology and nephrology》2007,39(2):629-633
Continuous ambulatory peritoneal dialysis (CAPD) is being used only in limited number of patients with renal failure due to
multiple myeloma, despite having better preservation of hemoglobin, higher clearance of paraproteins, and higher chances of
recovery of renal function than maintenance hemodialysis. We are reporting our short-term experience of five patients with
multiple myeloma who presented with renal failure and required long term continuous ambulatory peritoneal dialysis for the
treatment of uremia. 相似文献
108.
Lee TG Ahmad TS 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2007,28(9):984-990
BACKGROUND: The response of chronic plantar fasciitis to any treatment is unpredictable. Autologous blood might provide cellular and humoral mediators to induce healing in areas of degeneration, the underlying pathology in plantar fasciitis. This study compared the efficacy of intralesional autologous blood with corticosteroid injection for plantar fasciitis present for more than 6 weeks. METHODS: A prospective, randomized, controlled, observer-blinded study was done over a period of 6 months. Sixty-four patients were randomly allocated to either the autologous blood or corticosteroid treatment group. All patients were assessed for the worst pain daily on visual analogue scale (VAS) and tenderness threshold (TT) at the plantar fascia origin using a pressure algometer before treatment, and at 6 weeks, 3 months, and 6 months after treatment. A p value of 0.05 was considered significant. RESULTS: Data were complete for 61 patients. The reduction in VAS and increase in TT for both groups was significant over time (p < 0.0001). At 6 weeks and 3 months, the corticosteroid group had significantly lower VAS than the autologous blood group (p < 0.011 and p < 0.005, respectively), but the difference was not significant at 6 months. The corticosteroid group had significantly higher TT than the autologous blood group at 6 weeks, 3 months and 6 months (p < 0.003, p < 0.003, p < 0.008, respectively). Although the trends were different, repeated-measures F test of both VAS and TT showed no significant difference in improvement between the groups over time. CONCLUSIONS: Intralesional autologous blood injection is efficacious in lowering pain and tenderness in chronic plantar fasciitis, but corticosteroid is more superior in terms of speed and probably extent of improvement. 相似文献
109.
The purpose of this study was to examine the effect of sperm preparation by density gradient on the intra-individual variation in sperm motility. Patients presenting for density gradient (DG) sperm preparation were analyzed retrospectively. Patients who had more than one preparation were included. The variation within each patient was studied using the coefficient of variation (CV = standard deviation/mean x 100). Density gradient preparation resulted in a reduction in the CV of sperm motility (CV motility before DG: 19.8 +/- 15.82% vs. CV motility after DG: 15.9 +/- 17.97%, p < 0.001). However, CV of sperm concentration (44.2 +/- 26.51%) and CV progressively motile sperm (49.2 +/- 28.48%) remained very high after DG. This variability should be reflected in counseling patients undergoing intrauterine insemination. 相似文献
110.
Ahmad Sallehuddin Abdulrahman Mesned Maie Barakati Majid Al Fayyadh Fadel Fadley Zohair Al-Halees 《European journal of cardio-thoracic surgery》2007,32(2):195-200; discussion 201
OBJECTIVE: There are several modifications introduced in the preparation for a subsequent non-surgical transcatheter completion of the Fontan procedure. We report our experience with one type of the modification and the short-term results following its implementation. METHODS: During bidirectional cavopulmonary connection (BCPC) an intra-atrial lateral tunnel is additionally created, as intended for a Fontan procedure but fenestrated with a 10-14 mm aperture. The cardiac end of the superior vena cava (SVC) is then patched to maintain the physiology of BCPC. During the interventional transcatheter completion procedure, the SVC patch is perforated using radio-frequency (RF) energy, balloon-dilated, and stented as well. The aperture is closed with a device when required. Paired t-test was used to compare data before and after the Fontan completion. RESULTS: From June 2003 to February 2006, 16 patients (9 boys and 7 girls, mean age 12 months) underwent the surgical procedure described. The mean bypass time was 137 min and the mean ischemic time was 77 min. There were no operative deaths. One patient with bilateral SVC required a take down due to recurrent effusions. Ten months later, nine patients underwent completion (mean age 20 months, mean weight 10.6 kg). The stents were dilated to a mean diameter of 14.4mm. All except one aperture was closed with a device. The mean fluoroscopy time was 41 min. Oxygen saturation increased from 85 to 94% (p=0.001). Pulmonary artery pressures remained normal (16 mmHg before and 19 mmHg after, p=0.12). No patients required mechanical ventilation and none developed pleural effusions or arrhythmias. All were discharged from hospital within 6 days of the Fontan completion. Twenty-two months after Fontan, all were well. Echocardiography revealed no gradients across the stents. Two patients had minor leaks across the aperture. One underwent further stent dilatation a year later. CONCLUSIONS: Fontan completion without surgery is suitable in patients with single ventricles with lower mortality and morbidity, avoids multiple surgical interventions while maintaining the staged approach and allows for successive dilatation of the Fontan pathway to accommodate for growth. 相似文献