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71.
This experiment was designed to investigate whether addition of vitamin C to the solution used in tumescent technique of
liposuction might increase lipolysis and whether increased fibrosis might improve skin retraction where liposuction did not
work properly and the skin had poor retraction ability. Eighteen Sprague-Dawley rats were used in two groups. Both inguinal
fat pads of rats with their vascular structures were elevated and the right inguinal fat pad was injected with 1 cc tumescent
solution as a control and the left fat pad with a 1 cc vitamin C-tumescent solution. Histopathological examination showed
that all fat pads injected with tumescent solution had normal adipocytes. Those injected with vitamin C-tumescent were shown
to have extreme fibrosis and occasional adipocytes. 相似文献
72.
Adanali G Senen D Turegun M Tuncel A Erdogan B Albayrak L 《Aesthetic plastic surgery》2002,26(6):465-469
Androgenic alopecia is a serious problem for a large proportion of the population, especially males, and causes them to seek medical help. Many methods have been described for treatment of androgenic alopesia. Among them are punch grafts, strip grafts, scalp grafts, scalp reductions, tissue expanders, and flap combinations, and hair transplantations with minigrafts and micrografts. The latter has become popular in the last two to three decades and has been investigated extensively. Improvements in hair replacement with minigrafts and micrografts may allow an ideal result with a nearly normal appearance. However, hair replacement with these grafts has important disadvantages. It requires a long operational time and only a limited number of grafts can be placed in one session. In this study, we investigated morphological structures of micrografts stored at 4 degrees C and those stored at -20 degrees C. We found that morphological structures of the grafts stored at 4 degrees C started to be impaired in the fifth day, but that the morphological structures of the grafts stored at -20 degrees C remained unaltered for 15 days. If this method is put into practice, the use of minigrafts and micrografts available will not only obviate the second graft harvesting, but also allow reconstruction of a large area in a short period of time. 相似文献
73.
Late effects of TNF-alpha-induced inflammation on the microcirculation of cremaster muscle flaps under intravital microscopy 总被引:3,自引:0,他引:3
In order to understand the microcirculatory changes and regulatory mechanisms governing passage of neutrophils from the vascular bed to the interstitial tissue during ischemia/reperfusion (I/R) injury, a key component of this injury, tumor necrosis factor-alpha (TNF-alpha)-induced inflammation was analyzed. Twenty-four Sprague-Dawley rats were divided into four groups, containing six animals in each. The effect of TNF-alpha-induced inflammation was studied at two different time points, early sequential and late. In the early-effect Groups 1 and 2, animals were given TNF-alpha and vehicle, respectively. Microcirculatory changes were recorded for 6 hr continuously. In the late-effect Groups 3 and 4, following TNF-alpha injection and vehicle, microcirculatory changes were measured 16 hr later. In the early-effect groups, the number of rolling and adhering leukocytes was increased immediately following TNF-alpha injection and remained elevated for the first 3 hr (p<0.05). The number of transmigrated leukocytes remained significantly increased throughout the first 6 hr (p<0.05) and returned to normal at 16 hr. In delayed-effect groups, a second peak in the number of rolling leukocytes was noted at 16 hr (p<0.05). The numbers of rolling and adhering lymphocytes, although remained at the baseline for the first 6 hr, was increased 2- and 1.5-fold at 16 hr, respectively (p<0.05). The number of perfused capillaries gradually decreased over time in the TNF-alpha-induced inflammation groups. A vasodilatory response was noted at the third and fourth order arterioles within the first 3 hr of measurement (p<0.05), but returned to normal afterward. The detrimental effects of TNF-alpha-induced inflammation during I/R injury could be prolonged up to 16 hr at the microcirculatory level of the muscle flaps. 相似文献
74.
We used a hue-scaling task to examine changes in color perception resulting from adaptation or induction to color contrast in spatially-varying backgrounds. Observers judged the perceived color of tests after or while viewing backgrounds composed of color differences along selected axes in color space. Both contrast adaptation and contrast induction produced large and selective shifts in perceived hue angle, and interacted in similar ways when combined, suggesting that they had functionally similar influences on perceived hue. Both also consistently biased perceived hue away from the color axis of the background, implying response changes within multiple channels tuned to different directions in color space. Selective hue changes were also observed when the gamut of colors forming the backgrounds were drawn from natural color distributions. This suggests that color perception in different environments may be systematically biased by adaptation to the distributions of colors in those environments. However, we did not find these biases when the same test stimuli were judged after adapting to actual natural scenes. 相似文献
75.
The prevalence of Cryptosporidium infection in patients who are on chronic hemodialysis due to end-stage renal failure is investigated and compared with the incidence in the healthy population. Stool specimens of 74 adult hemodialysis patients treated on an outpatient basis and 50 healthy individuals are examined for Cryptosporidium oocysts by using the modified acid-fast method. While 20.27% (15/74) of patients in the dialysis group had Cryptosporidium oocysts in their stools, none (0/50) of the controls had such an infection (p < 0.001). Ten of 15 patients who had Cryptosporidium oocysts in their stool specimens were asymptomatic and the remaining 5 had diarrhea. Four of these 5 diarrheic patients had Cryptosporidium oocysts in their stools and 1 had both Cryptosporidium oocysts and Giardia trophozoites. Since hemodialysis patients with chronic renal failure are candidates for renal transplantation, general preventive measures against infection must be taken and these patients must be screened for their carrier state before transplantation. 相似文献
76.
Yalvac S Kayikcioglu F Boran N Tulunay G Kose MF Bilgic S Haberal A 《Cancer investigation》2002,20(5-6):754-758
Ligation of the hypogastric artery has been a standard and effective procedure in controlling massive bleeding in advanced cervical carcinoma. The authors wanted to demonstrate the selective use of embolization of hypogastric or uterine artery to achieve the same end result--the stoppage of vaginal bleeding. In a number of cases, surgical approach may not be appropriate either because of the critically ill patient or because of the highly deformed pelvic anatomy due to radiotherapy or to the recurrence of cancerous tissue. As an alternative therapy, we used selective embolization of the uterine artery in eight patients. In all the patients, embolization served to control bleeding. As the bleeding was brought under control, a gradual recovery of the patient was generally observed. The most common side-effect was temporary severe pain related to ischemia of tumoral tissue. Embolization may be regarded as an effective procedure, which can be used to control massive bleeding in selected cervical cancer patients. 相似文献
77.
Systemic amyloidosis is an unusual cause of generalized massive lymphadenopathy. In such cases the clinical picture may mimic lymphoma. We report a case of generalized massive lymphadenopathy caused by amyloidosis. The 55-year old female patient was admitted to our hospital with dyspnea and edema in the lower extremities. These were diminished breath sounds with bilateral basal congestion hepatosplenomegaly and generalized massive lymphadenopathy in axillary, cervical, and inguinal areas. The diagnosis was made by excisional biopsy of one of the involved lymph nodes. Amyloidosis (AL type) was shown and treatment with melphalan and prednisone was initiated. Unfortunately the patient died after 51 days in hospital. 相似文献
78.
Intracerebroventricular (i.c.v.) injection of choline (50-150 microg), a precursor of the neurotransmitter acetylcholine, produced a time-and dose-dependent increase in plasma vasopressin levels in conscious, freely moving rats. The increase in plasma vasopressin in response to i.c.v. choline (150 microg) was inhibited by pretreatment with the nicotinic receptor antagonist, mecamylamine (50 microg; i.c.v.), but not by the muscarinic receptor antagonist, atropine (10 microg; i.c.v). The choline-induced rise in plasma vasopressin levels was greatly attenuated by hemicholinium-3 (HC-3; 20 microg; i.c.v.), a neuronal choline uptake inhibitor. Choline (50 or 150 microg; i.c.v.) produced a much greater increase in plasma vasopressin levels in osmotically stimulated or hemorrhaged rats than in normal rats. Choline (150 microg; i.c.v.) also enhanced plasma vasopressin response to graded hemorrhage; the enhancing effect of choline was also attenuated by HC-3 (20 microg; i.c.v.). Choline and acetylcholine concentrations in hypothalamic dialysates increased significantly following i.c.v. injection of choline (150 microg). It is concluded that choline increases plasma vasopressin levels by stimulating central nicotinic receptors indirectly, through the enhancement of acetylcholine synthesis and release, and augments the ability of osmotic stimulations or hemorrhage to stimulate vasopressin release. 相似文献
79.
Diabetes mellitus is one of the major causes of chronic renal failure. Typical findings of diabetic nephropathy are early hyperfiltration followed by microalbuminuria and overt proteinuria, resulting in a progressive decrease in glomerular filtration rate. Rapidly progressive glomerulonephritis has rarely been reported in patients with diabetes mellitus. Here, we describe a patient with MPO-ANCA-associated vasculitis, presenting with pulmonary-renal syndrome. Immunosuppressive treatment, including pulse methyl-prednisolone and cyclophosphamide, was administered and the disease was resolved. 相似文献
80.
Aykut US Yazici M Kandemir U Gedikoglu G Aksoy MC Cil A Surat A 《Journal of pediatric orthopedics》2005,25(3):336-341
The purpose of this study was to investigate the effect of temporary hemiepiphyseal stapling on the bone geometry and proliferative activity of the physis in immature rabbits. Proximal medial epiphyseal stapling of the right tibia was performed in 46 6-week-old New Zealand white rabbits. The rabbits were assigned randomly into two groups. In group 1, the staples were inserted extraperiosteally and the rabbits were killed at the end of 3 weeks. In group 2, the staples were fixed subperiosteally (group IIA) or extraperiosteally (group IIB), the staples were removed at the end of 3 weeks, and the rabbits were killed at the end of 6 weeks. The articular line-diaphysis angle (ALDA) was significantly increased with 3 weeks of stapling. After the removal of staples, while ALDA continued to worsen in group IIA, it improved in group IIB. Bone was observed to bridge the physis in group IIA. However, the proliferative activity of the physis continued. Temporary hemiepiphyseal stapling is a safe and effective method for control of physeal growth of long bones before skeletal maturity. However, it is of paramount importance not to disturb the periosteum during stapling. 相似文献