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排序方式: 共有1511条查询结果,搜索用时 31 毫秒
1.
HOCK LEONG EE  MBBS  MRCP    CHEE LEOK GOH  MBBS  FRCP    KHOO    ES-Y. CHAN  PHD    POR ANG  MBBS  MRCP 《Dermatologic surgery》2006,32(1):34-40
BACKGROUND: Acquired bilateral nevus of Ota-like macules (Hori's nevus) is a common dyschromatosis among Asian women. Q-switched lasers have been used successfully as a treatment modality. OBJECTIVE: The purpose of this study was to compare the efficacy of using the Q-switched 532 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser followed by the 1,064 nm laser versus the Q-switched 1,064 nm Nd:YAG laser alone in the treatment of Hori's nevus. METHODS: This is a prospective left-right comparative study. Ten women with bilateral Hori's nevus were recruited and treated with a combination of the Q-switched 532 and 1,064 nm Nd:YAG lasers on the right cheek and the Q-switched 1,064 nm Nd:YAG laser alone on the left cheek. Only one laser treatment session was performed. The degree of pigmentation was objectively recorded with a mexameter. Subjective assessment was made by both patients and two blinded, nontreating dermatologists. RESULTS: At 6 months, there was a statistically significant difference (p = .009) of 35.10 points using objective mexameter measurements between the two sides, favoring the side treated with a combination of 532 and 1,064 nm laser treatment. Subjective grading by the patients and blinded dermatologists also confirmed that combination therapy was more successful after one treatment. Although combination treatment had a higher incidence of mild postinflammatory changes, this disappeared within 2 months. CONCLUSIONS: Concurrent use of the Q-switched 532 nm Nd:YAG laser in combination with the 1,064 nm laser is more effective in pigment clearance than the Q-switched 1,064 nm Nd:YAG laser alone for Hori's nevi.  相似文献   
2.
We have developed a luminol-based assay using intact islets, which allows for quantification of reactive oxygen species (ROS). In addition, an index capable of characterizing metabolic and mitochondrial integrity prior to transplantation was created based on the capacity of islets to respond to high glucose and rotenone (mitochondrial respiratory chain complex I inhibitor) by production of ROS. To validate this assay, lipid peroxidation and antioxidative defense capacity were evaluated by detection of malondialdehyde (MDA) levels and glutathione peroxidase activity (GPx), respectively. Also, flow cytometric analyses of ROS (dihydroethidine), apoptosis (Annexin V, active caspases), necrosis (Topro3), and mitochondrial membrane potential (JC-1) were done in parallel to correlate with changes in luminol-measured ROS. ATP/ADP ratios were quantified by HPLC and the predictive value of ROS measurement on islet functional potency was correlated with capacity to reverse diabetes in a streptozotocin-induced diabetic NOD.scid mouse model as well as in human transplant recipients. Our data demonstrate that levels of ROS in islets correlate with the percentage of apoptotic cells and their functional potency in vivo. The ROS indices following glucose and rotenone exposure are indicative of metabolic potency and mitochondrial integrity and can be used as surrogate markers to evaluate the quality of islets prior to transplantation.  相似文献   
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Kim  EE; Pjura  G; Lowry  P; Verani  R; Sandler  C; Flechner  S; Kahan  B 《Radiology》1986,159(2):443-446
Serial radionuclide studies using both Tc-99m DTPA (perfusion) and I-131 hippuran (tubular function) were correlated with histologic findings in 25 patients with renal transplants. These cases included 15 cases of cyclosporin-A nephrotoxicity (CsA-NT) and ten cases of acute cellular rejection that were retrospectively selected on the basis of biopsy findings and favorable clinical response to therapy specific for each of these conditions. The serial radionuclide studies enabled the correct diagnosis in 12 of 15 cases of CsA-NT and eight of ten cases of acute rejection. Posttherapy radionuclide studies, furthermore, demonstrated improvement consistent with clinical response. In all cases, the radionuclide results were available at least 24 hours before biopsy findings. These results indicate that serial radionuclide studies evaluating interval changes in both perfusion and tubular function are of significant value in the diagnosis and follow-up of CsA-NT and acute cellular rejection in transplant recipients. This initial experience suggests a sensitivity of 80%.  相似文献   
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Proximal dorsal stress risers are a potential complication to the Kalish osteotomy. The authors describe a modification to this osteotomy that is simple and effective. Since performing the wing-clip modification, there have been no observed stress risers.  相似文献   
7.
Interalar width as a guide in denture tooth selection   总被引:2,自引:0,他引:2  
This study was undertaken to determine the relationship of the IAW, measured between at the widest dimension of the alae of the nose, and two other measurements of maxillary anterior teeth. The other measurements, both of which are significant in the selection and arrangement of artificial teeth used in complete dentures, were the ICTW and the ARCD measured from the distal surface of the maxillary canine on one side of the arch to the distal surface of the canine on the opposite side of the arch. No distinction was made between either the sex or the age of the subjects. The mean ICTW of 35.35 mm was 3% greater than the mean IAW of 34.28 mm. The mean ARCD of 44.85 mm was 31% greater than the mean IAW of 34.28 mm. This mean ARCD compares favorably (less than 1 mm difference) with a constructed ARCD of 45.8 mm from a tooth dimension study by Shillingburg et al. The ARCD was 44.85 mm. This measurement had not been made in the previous study examining the relationship of interalar distance to ICTW. When the IAW was plotted against the intercanine cusp tip width, a fairly strong correlation coefficient of 0.413 was exhibited. A weaker but definite correlation coefficient of 0.217 was observed when the interalar width plotted against the circumferential arc distance from distal surface to distal surface of the maxillary canines.  相似文献   
8.
Diagnostic and surgical implications of child abuse   总被引:1,自引:0,他引:1  
One hundred fifty-six children younger than 13 years of age with blunt abdominal injuries were reviewed, and those injured in accidents (89%) were compared with those injured by child abuse (11%). Abused children were younger (mean age, 2 1/2 years) and all presented late to medical attention with a history that was inconsistent with their physical findings. Only 65% of abused children had physical or roentgenographic signs of prior abuse, while 35% had no signs of prior abuse. The abdominal organs injured were different; 61% of accidentally injured children suffered injuries to a single, solid organ, and only 8% had hollow viscus injuries, while 65% of abused children had hollow viscus injuries. Physicians should suspect child abuse when children have unexplained injuries (especially young children with hollow viscus injuries) even when other signs of child abuse are absent, and they should suspect hollow viscus injury in abused children.  相似文献   
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Patients with sickle cell anemia have considerably less hypertension than the black population in general. Factor(s) offering "protection" from hypertension in these patients remain unknown. Hormonal and hemodynamic parameters involved in blood pressure regulation were evaluated in normotensive, stable sickle cell patients and black nonsickle normotensive controls. There was no difference in systolic, diastolic, or mean arterial blood pressure between the two groups. The characteristic hemodynamic findings of increased cardiac index, renal plasma flow, and plasma volume were observed in the sickle cell patients. Urinary sodium excretion was comparable on an ad libitum, high sodium, and low sodium diet. In contrast, plasma renin activity was greater in sickle cell patients at all levels of sodium intake in both supine and upright positions. These findings suggested possible altered vascular responsiveness to endogenous angiotensin II. Plethysmography revealed that sickle cell patients had greater forearm blood flow than normal controls and black nonsickle chronic anemic controls at rest, during cold stimulation, and during exercise. Forearm vascular resistance was significantly lower in the patients and did not increase with cold-induced, sympathetic-mediated stimulation. To assess these findings more directly, the pressor response to the exogenous administration of graded doses of angiotensin II and norepinephrine was measured. There was a marked decrease in the pressor response to angiotensin II but not to norepinephrine in the sickle cell patients. The findings in these studies indicate fundamental differences in blood pressure control in the sickle cell patient, probably at the vascular level.  相似文献   
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