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There are various changes in the thyroid gland and its function in chronic renal failure (CRF). These changes include lower levels of circulating thyroid hormone, altered peripheral hormone metabolism, decreased binding to carrier proteins, possible reduction in tissue hormone content, and increased iodine storage in the thyroid gland. The decrease of excretion of urinary iodine in CRF increases serum inorganic iodine level and iodine content of the thyroid, which consequently enlarges the gland. This study is designed to investigate the prevalence of goiter and thyroid dysfunction in patients with end-stage renal disease (ESRD) on hemodialysis (HD) in an iodine-deficient community. Eighty-seven (40 females and 47 males) HD patients and 169 (79 females and 90 males) healthy individuals as controls are included. Sex ratios for the patient and control groups are 0.85 and 0.88, respectively. Mean ages for the patient and control groups are 42.94 +/- 11.88 and 40.20 +/- 10.72 years, respectively. Examination of the thyroid gland using ultrasonography along with simultaneous measurement of blood levels of free-T4 (FT4), free-T3 (FT3), and thyrotropin (TSH) are made for every individual. The presence of goiter demonstrable by ultrasonography is found in 32.2% of the uremic patients and in 23.5% of the controls and its prevalence increases with age (P = 0.01). In 32 (36.8%) of the patients and 29 (17.1%) of the controls at least one thyroid nodule is found in ultrasonography. Between patients with or without a nodular goiter the authors could not observe any difference for duration of dialysis and serum levels of TSH, FT4, FT3, calcium, and albumin. In ESRD patients the prevalence of nodular goiter is higher for females (47.5% vs. 27.7%, P = 0.045) and increases with age (P = 0.04). Though incidence of hyperthyroidism is found to be similar for the two groups (1.14% in ESRD patients vs. 1.10% in controls), hypothyroidism is observed in 3.4% of ESRD patients but only 0.6% of controls. This high incidence of hypothyroidism and nodular goiter in ESRD patients shows that screening for thyroid dysfunction and goiter, using appropriate laboratory tests and ultrasonography, should be considered in evaluation of every ESRD patient.  相似文献   
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Anomalies of major retroperitoneal vascular structures have been showed up in many reports so far. Here, a group of vascular anomalies of retroperitoneum were reported, all of which were encountered during the staging surgery of a 65-year-old woman with endometrium carcinoma. There was no vascular injury during the surgery associated with these vascular abnormalities. Since they are met quite frequently, it is important for surgeons dealing with retroperitoneum to be aware of the possible anomalies of vascular and renal structures in this region.  相似文献   
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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   
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Subarachnoid hemorrhage (SAH) of spinal origin is a rare entity accounting for approximately 1% of all cases of SAH. Its most frequent causes are trauma and vascular malformations. Although primary spinal tumors, especially ependymomas, are also relatively common causes, SAH secondary to a metastatic spinal tumor arising from outside the central nervous system is an extremely rare condition; only one case has been reported in the literature. The authors present a case of spinal meningeal carcinomatosis secondary to cutaneous malignant melanoma in which the patient presented with only symptoms of SAH. Although very rare, this case underscores several factors. 1) Spinal SAH due to spinal metastases should be considered in the differential diagnosis of patients with previously known malignancy. 2) Spinal SAH may manifest without paraparesis or sensory deficit. 3) Magnetic resonance imaging of the spinal cord may be important to determine the source of SAH in patients in whom four-vessel cerebral angiography demonstrates no abnormal findings.  相似文献   
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Background/Purpose

The aim of this study was to investigate the effect of peritonitis on spontaneous contractions of distal and proximal colon smooth muscle isolated from rats.

Methods

Peritonitis was induced by cecal ligation and puncture in 8 rats. Another group of 8 rats underwent a sham operation and acted as controls. Twenty-four hours after the operation, the rats were killed; and their distal and proximal colon smooth muscle was excised and placed in circular muscle direction in a 10-mL organ bath. Changes in the amplitude and frequency of contractions were analyzed before and after the addition of antagonists.

Results

Peritonitis induced the increase in the amplitude and frequency of spontaneous contractions. In both distal and proximal colon of the control group, the amplitude of spontaneous contractions was elevated by NG-nitro-l-arginine and tetradotoxin; but the frequency of spontaneous contractions was significantly elevated only in the presence of NG-nitro-l-arginine. In both distal and proximal colon of the peritonitis group, the enhanced amplitude and frequency were significantly decreased and returned to control values in the presence of celecoxib.

Conclusions

Peritonitis induces the increase in the amplitude and frequency of spontaneous contractions of distal and proximal colon, which can be attributed to a loss of inhibitor nitrergic and other neural control or rise of cyclooxygenase-2 levels.  相似文献   
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Elevated circulating levels of soluble adhesion molecules as markers of endothelial dysfunction have been related to insulin resistance and its associated metabolic abnormalities. However, their associations with type 2 diabetes remain inconclusive. We conducted a prospective nested case-control study to examine the associations between plasma levels of E-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) and diabetes risk among 82,069 initially healthy women aged 50-79 years from the Women's Health Initiative Observational Study. During a median follow-up of 5.9 years, 1,584 incident diabetes case subjects were matched with 2,198 control subjects by age, ethnicity, clinical center, time of blood draw, and follow-up time. Baseline median levels of the biomarkers were each significantly higher among case subjects than among control subjects (E-selectin, 49 vs. 37 ng/ml; ICAM-1, 324 vs. 280 ng/ml; and VCAM-1, 765 vs. 696 ng/ml [all P values <0.001]). After adjustment for risk factors, the relative risks of diabetes among women in the highest quartile versus those in the lowest quartile were 3.46 for E-selectin (95% CI 2.56-4.68; P for trend <0.0001), 2.34 for ICAM-1 (1.75-3.13; P for trend <0.0001), and 1.48 for VCAM-1 (1.07-2.04; P for trend = 0.009). E-selectin and ICAM-1 remain significant in each ethnic group. In conclusion, higher levels of E-selectin and ICAM-1 were consistently associated with increased diabetes risk in a multiethnic cohort of U.S. postmenopausal women, implicating an etiological role of endothelial dysfunction in the pathogenesis of type 2 diabetes.  相似文献   
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Although there is a controversy about success and failure of autologous fat tissue transfers, it is a widely accepted method for soft tissue augmentation and is performed by many plastic surgeons as well as dermatologists all around the world. Its advantages are that it does not cause reactions, its absorption rates have been reduced by increased knowledge, experience, and techniques, it can yield good, long-term results, and there are now preservation techniques that allow reinjections when necessary. However, no single ideal technique has been determined. In this paper a new, simple, T-shaped adaptor for easy, quick, and efficient fat harvesting during liposuction is described. This study not only describes the clinical use of the adaptor, but also histologically examines its effects on fat cells under various vacuum pressures (-250 mmHg, -500 mmHg, -700 mmHg). The study shows that the cell structure of fat tissue harvested under medium power (with vacuum pressures of -250 mmHg and -500 mmHg) is not disrupted, while that of tissue harvested with a vacuum pressure of -700 mmHg was traumatized and occasional cell wall fragmentation occurred. In conclusion, it is shown that the T-shaped adaptor allows harvesting of the desired amount of fat tissue without causing trauma to fat cells when it is used with medium-power suction.  相似文献   
10.
OBJECT: The authors undertook a study to explore the topographic anatomical features seen during the anterolateral approach to cervical spine, anatomical variations, and certain landmarks related to the surgical procedure. METHODS: The study was conducted in 30 fresh cadavers. RESULTS: The common carotid artery bifurcation was mostly found at the level of C-4 (78%). The inferior belly of the omohyoid muscle was seen to cross the sternocleidomastoid muscle at the C5-6 disc level along the entire C-6 vertebral body. To reach the lower cervical region, the sacrifice of this muscle makes the procedure easier. The facial vein drained into the internal jugular vein mostly at the level of C3-4 (54%). The superior ganglion of the cervical sympathetic chain was located at the C-4 vertebra, but the location of the intermediate ganglion exhibited some variation. The vertebral artery entered the transverse foramen of C-6 in 27 cadavers (90%), the transverse foramen of C-7 in two cadavers (7%), and the transverse foramen of C-4 in one cadaver (3%). Because the inferior thyroid artery crossed the C6-7 interspace obliquely, the course of the inferior thyroid artery may complicate the procedure. The C-5 uncinate process was shortest and narrowest and had the greatest distance from the medial edge of the process to the anterior tubercle (p < 0.001). CONCLUSIONS: Understanding the qualitative anatomy of this region not only improves the safety of anterior and anterolateral cervical spine surgery but also allows adequate decompression of neural elements and resolution of the other pathological processes of this region. In this fresh cadaveric study, our goal was to improve the approach and decrease the incidence of complications.  相似文献   
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