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141.
Electrodiagnostic tests measuring the activities of cavernous smooth muscle and sudomotor structures of penile skin are used in order to evaluate autonomic innervation of the penis. Owing to closeness of these tissues, the interference of sympathetic activity during recording is a possibility. In this study, we investigated this possibility in 10 patients whose cavernosal tissues were destroyed during penile prosthesis implantation by comparing the pre- and postoperative penile skin electrodermal activities. Penile electrodermal activities were recorded with surface electrodes before and after the operation. All of the patients had spontaneous and evoked penile electrodermal activity (EDA). The mean amplitude of evoked EDA decreased from 2159+/-700 to 1413+/-515 microV following penile prosthesis surgery (P=0.017). The decrease in the amplitude of penile-evoked EDA following penile prosthesis implantation suggests the contribution of cavernous smooth muscle activity to the sudomotor responses prior to operation. Although corpus cavernosum sympathetic activity contributes to the penile skin recordings, these recordings are mostly the result of penile skin sudomotor sympathetic activity. Therefore, surface potentials recorded from penile skin should not be used for the evaluation of autonomic innervation of corpus cavernosum.  相似文献   
142.
BACKGROUND: Laparoscopy is used for almost all types of abdominal surgery because of its advantages, which include shorter postoperative hospital stay. However, pneumoperitoneum used to facilitate the visual field has severe metabolic, hemodynamic, and inflammatory consequences depending on the pressure level and the gas used. Helium (He), an inert gas, has been recommended for establishment of pneumoperitoneum since it does not alter the blood pH and PCO(2). Yet the oxidative response after He insufflation remains unknown. This study was undertaken to compare the levels of free radical production and antioxidant status following He and CO(2) pneumoperitoneum at different intra-abdominal pressure values. MATERIALS AND METHODS: The subjects were 40 Sprague-Dawley male rats randomized to the following groups: He 10 (n = 8) was subjected to He pneumoperitoneum at 10 mm Hg for 60 minutes; He 15 (n = 8) was subjected to He pneumoperitoneum at 15 mm Hg for 60 minutes; CO(2) 10 (n = 8) was subjected to CO(2) pneumoperitoneum at 10 mm Hg for 60 minutes; CO(2) 15 (n = 8) was subjected to CO(2) pneumoperitoneum at 15 mm Hg for 60 minutes; and Control (n = 8) was subjected to sham operation without pneumoperitoneum. At the end of the experiment blood samples were obtained and plasma malondialdehyde, carbonyl, and sulphydryl levels were measured. RESULTS: CO(2) pneumoperitoneum produced higher malondialdehyde and carbonyl responses and sulphydryl consumption compared to He, especially at 15 mm Hg (P = 0.01, P = 0.01, and P = 0.059, respectively). CONCLUSION: Helium seems to limit the postoperative oxidative response following laparoscopy.  相似文献   
143.
Using electron microscopy, the smooth musculature of human and laboratory animal bronchi, intestine and ureters was found to contain smooth myocytes of light and dark types, which had the cytoplasm of different electron density. Both types of myocytes are characterized by a high degree of differentiation. The significant differences between light and dark myocytes were detected in the ultrastructural organization of their contractile elements. On the basis of data obtained, light and dark myocytes should be considered as mature cells in different phases of their functional activity. Some part of them, light myocytes, are in the state of "passive" contraction and may serve as a tissue functional reserve. Mutual transformation of light and dark myocytes seems to be possible and may be caused by functional requirements, which are realized at the level of tissue regulation.  相似文献   
144.
Virus-specific memory T cell populations demonstrate plasticity in antigen recognition and in their ability to accommodate new memory T cell populations. The degeneracy of T cell antigen recognition and the flexibility of diverse antigen-specific repertoires allow the host to respond to a multitude of pathogens while accommodating these numerous large memory pools in a finite immune system. These cross-reactive memory T cells can be employed in immune responses and mediate protective immunity, but they can also induce life-threatening immunopathology or impede transplantation tolerance and graft survival. Here we discuss examples of altered viral pathogenesis occurring as a consequence of heterologous T cell immunity and propose models for the maintenance of a dynamic pool of memory cells.  相似文献   
145.
OBJECTIVE: The aim of this study was to determine the syndromic etiology of bilateral severe sensorineural hearing disorders in children and current etiological causes to reduce the cases in the unknown group. METHODS: This study was conducted on 550 students of five schools for the deaf in Istanbul and Zonguldak, Turkey. Otologic, audiologic, dysmorphologic, ophthalmologic and dental examinations were performed in all children. Familial and medical histories were obtained. RESULTS: The etiology of hearing loss was genetic in 346 (62.90%), acquired in 107 (19.45%) and unknown in 97 (%17.63) cases. A total of 619 malformations were defined in 550 children and 99 of them belonged to a syndrome. We identified 33 different syndromes for these 99 syndromic children. Syndromic etiology was found in 18.0% of the total and 28.61% of the subjects with genetic etiology. Most common syndrome was Waardenburg syndrome which occurred in 33 children. CONCLUSION: The incidence of hereditary hearing impairment is very high in developing countries compared to developed countries. Prevention is essential to reduce the incidence, multidisciplinary approach and genetic counselling are necessary in this regard.  相似文献   
146.
The authors report an extremely rare case of complete fistula of the second branchial cleft, with an external opening in the skin and an internal opening in the oropharyngeal mucosa. A 13-year-old girl presented with the complaint of intermittent drainage from the right side of her neck, a problem that had existed since birth. Fistulography revealed a complete fistula of the second branchial cleft. Before surgical excision, a 4-F catheter and a 0.018-in guide-wire were inserted into the external opening of the fistula and passed through to the tonsillar region under fluoroscopic guidance. The infrahyoid segment and parapharyngeal segment of the fistula were then excised through first- and second-step neck incisions, respectively. In this case, tonsillectomy was not necessary. Pathological examination of the wall of the fistula revealed lymphoid tissue containing lymphoid follicles. This report describes a technique in which complete excision of a fistula of the second branchial arch is facilitated by placing a catheter in the tract.  相似文献   
147.
A number of growth factors, their binding proteins, and their receptors have been shown to be induced in the hypoxic-ischemic (HI) brain. In this prospective study, we aimed at determining the levels of insulin-like growth factor 1 (IGF-1), growth hormone (GH), and cortisol in HI babies and at identifying whether they differ from the levels of control infants. The serum IGF-1 levels were measured after the first 12-24 h of life, and the measurements were repeated on the 5th and 10th days of life for babies with HI encephalopathy (n = 18) and on the 10th day of life for controls (n = 19). Blood samples for measurement of cortisol and GH from both HI and control groups were collected after the first 12-24 h of life. There were 11 babies in the mild-to-moderate (stages I and II) group and 7 babies in the severe (stage III) group according to Sarnat and Sarnat. The IGF-1 levels of the HI group measured after 12-24 h [78.5 +/- 27.9 (range 9-123.4) ng/ml] and on the 10th day [72.2 +/- 36.8 (range 29.7-159.2) ng/ml] of life were statistically significantly lower than the IGF-1 levels of the control group [121.5 +/- 50.4 (range 74.4-280.5) ng/ml and 133.1 +/- 34.4 (range 65.9-202) ng/ml, respectively] (p = 0.002 and p = 0.001, respectively). But there was no statistically significant difference between mild-to-moderate HI group and severe HI group in terms of IGF-1 levels after 12-24 h and 5 and 10 days of life (p > 0.05). Also there was no statistically significant difference in IGF-1 values after the first 12-24 h and after 10 days of life between HI subjects who died or survived (p > 0.05). The GH levels of the HI group after the first 12-24 h of life [34.6 +/- 32.3 (range 0.1-120) mIU/l] were statistically significantly higher than those in the control group [10.4 +/- 4.5 (range 3.7-16.9) mIU/l] (p = 0.005). There was no statistically significant difference in the serum cortisol levels between HI and control groups after the first 12-24 h of life [18.7 +/- 17.0 (range 1.6-65.1) microg/dl vs. 10.8 +/- 5.4 (range 3.0-23.2) microg/dl] (p > 0.05). No statistically significant correlation was found between IGF-1 levels and GH and cortisol levels of the HI encephalopathy group [r = -0.113 (p > 0.05) and r = 0.108 (p > 0.05), respectively]. In conclusion, this study showed decreased levels of serum IGF-1 and increased levels of GH which may be secondary to serum IGF-1 influx from the circulation to the brain as a protective mechanism or may be due to some cytokines which alter the GH/IGF axis, inhibit the action of IGF-1, and stimulate IGF-binding protein 1.  相似文献   
148.
149.
Twenty-six patients with moderate-to-severe hallux valgus deformities were evaluated before and after treatment. All of the patients had incongruent great toe joints. The patients underwent modified proximal crescentic osteotomy, which was termed proximal oblique crescentic osteotomy. The results were evaluated at an average follow-up time of 55 weeks. Objective criteria were hallux valgus angle, intermetatarsal angle, shortening of the first metatarsal, and angulation at the osteotomy site. Clinical evaluation was made according to the rating system of the American Orthopaedic Foot and Ankle Society. The mean correction of the hallux valgus and intermetatarsal angles was 22.1 degrees and 9.9 degrees, respectively. Short-term results indicate that proximal oblique crescentic osteotomy is effective in the treatment of hallux valgus; its advantages over other procedures include its technical ease and low rate of complications.  相似文献   
150.
PURPOSE: To measure microvascular blood flow in patients with unilateral exfoliation syndrome (XFS) without glaucoma or ocular hypertension and to compare the values in the eyes with clinically detected exfoliation, their nonexfoliative fellow eyes of the same patients and control eyes. METHODS: Twenty-two patients with clinically detected unilateral XFS and 30 age-matched healthy subjects were included in this study. Group 1 consisted of 22 eyes with clinical XFS, and the nonexfoliative fellow eyes of the same patients formed Group 2. The control group (Group 3) comprised te randomly selected eyes of 30 age-matched healthy subjects. Ocular blood flow values (volume, flow and velocity) were recorded from the opti nerve head (ONH) and peripapillary retina (PPR) using the Heidelberg retinal flowmeter (HRF). The difference between the three groups were compared statistically. RESULTS: The mean values of blood flow obtained from the ONH and PPR in eyes with clinically detected exfoliation (Group 1) and their nonexfoliative fellow eyes (Group 2) were both significantly lower than the values for the control eyes (Group 3). The differences in ocular blood flow between the eyes with exfoliation and the nonexfoliative fellow eyes were not statistically significant [one-way analysis of variance (ANOVA), Dunnett's T3 test, p >/= 0.05]. CONCLUSION: These findings suggest that the eyes with clinically detected unilateral XFS were associated with reduced blood flow values in both the ONH and the PPR. The nonexfoliative fellow eyes also have lower blood flow values than the control eyes.  相似文献   
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