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71.
OBJECTIVE: Our aims were to evaluate the detectability, configuration, location, and dimensions of the cisterna chyli on heavily T2-weighted images obtained with a single-shot fast spin-echo technique and to determine whether the disorders that have the potential to affect the abdominal lymphatic drainage could change the cisternal dimensions. MATERIALS AND METHODS: Thin-collimated axial and coronal images that were originally obtained for MR cholangiopancreatography in 125 patients were reviewed by three observers individually for the presence of abdominal lymphatic confluence. The configuration, location, and dimensions of hyperintense ductal or saccular structures immediately anterior to the vertebral bodies below the diaphragma were recorded. The differences between the mean values of the diameters of the cisterna chyli obtained in the control group and in groups in which lymphatic drainage was expected to be abnormally high were compared using a one-way analysis of variance test. RESULTS: Abdominal confluence of the lymphatics was shown in 96% of patients. The most common configuration of the cisterna chyli was tubular (42.5%). It was located at the level of L1-2 in 33% of cases and at the midline in 70%. Mean longitudinal, anteroposterior, and transverse diameters of the duct were 33.45 +/- 1.74 (SD) mm, 5.23 +/- 0.13 mm, and 5.23 +/- 0.15 mm, respectively. No significant difference was found in the mean values of antero-posterior, transverse, and longitudinal diameters of the cisterna chyli in the control group and in the groups expected to have an increased flow into the cisterna chyli. CONCLUSION: Abdominal confluence of lymphatics seems to be present on most of the heavily T2-weighted images. Its morphologic details and extensions can be visualized on images reconstructed with a maximum-intensity-projection algorithm. Any disorder does not necessarily lead to dilatation of these lymphatic structures.  相似文献   
72.
A case of a 10-year-old boy with hypoplasia of the flexor pollicis longus and without other associated anomalies and trauma history is reported. Flexor pollicis longus tendon anomalies are rare; several types of this congenital anomaly have been reported in the literature. The diagnosis should be considered to the conditions of a patient who was unable to flex the interphalangeal joint of the thumb. Hypoplastic thumb or absent interphalangeal joint crease may be a diagnostic feature in such cases. We preoperatively present the radiological findings of this rare congenital anomaly. Ultrasound and magnetic resonance imaging (MRI) features have never been reported in the literature.  相似文献   
73.
Toll-like receptors (TLRs) belonging to pattern recognition receptors are involved in maintaining testicular and epididymal immune homeostasis. The purpose of the current study was to investigate TLR4 expression in rat testis and epididymis throughout postnatal development. Weak staining was detected in peritubular myoid cells and immature Sertoli cells while no staining was observed in gonocytes during prepubertal period. However, TLR4 expression began to appear in spermatocytes in pubertal period and gradually increased in spermatids. An intense staining was observed in steps 5–19 spermatids in post pubertal and mature periods. Similarly, TLR4 expression in the testes steadily increased from pubertal period to mature period. Puberty also caused a significant increase in TLR4 expression in epididymis. TLR4 expression in cauda epididymis was lower as compared to those of other epididymal segments. The majority of epididymal epithelial cells exhibited apical TLR4 expression, whereas basal cells showed intense intracytoplasmic immunoreaction. We detected an intense staining in epididymal smooth muscle cells. The expression levels of TLR4 showed dynamic changes in both spermatogenic cells, and entire testicular and epididymal tissues during postnatal development. These results suggest that TLR4 expression contributes not only to inflammation but also to the development of spermatogenic cells.  相似文献   
74.
BACKGROUND AND PURPOSE: Subarachnoid hemorrhage (SAH) constitutes an important neurologic emergency. Some authors have suggested that fluid-attenuated inversion recovery (FLAIR) MR imaging can detect SAH that may not be apparent on CT scans but may be revealed by lumbar puncture. We sought to determine how often FLAIR MR imaging findings are positive for SAH in cases with negative CT findings and positive lumbar puncture results. METHODS: The CT scans and FLAIR MR images of all patients with suspected SAH during a 3-year interval (2000-2002) were retrospectively reviewed by a blinded reader. Among these cases, we identified 12 with CT findings that were negative for SAH, lumbar puncture results that were positive for SAH, and FLAIR MR imaging findings that were available for review. Eleven of the 12 patients had undergone FLAIR MR imaging within 2 days of CT and lumbar puncture. The 12 patients with negative CT findings were comprised of six male and six female patients with an age range of 7 to 69 years. We evaluated the true and false negative and positive FLAIR MR imaging findings for SAH by using the lumbar puncture results as the gold standard. The FLAIR MR imaging findings of 12 additional patients without SAH (as revealed by lumbar puncture) were used as control data for a blinded reading. RESULTS: For all 12 control cases without SAH, the FLAIR MR imaging findings were interpreted correctly. Of the 12 cases that had positive lumbar puncture results but false-negative CT findings for SAH, FLAIR MR imaging findings were true-positive in only two cases and were false-negative in 10. One of the two true-positive cases had the highest concentration of RBC in the series (365 k/cc), and the other had the second highest value of RBC (65 k/cc). CONCLUSION: FLAIR MR imaging cannot replace lumbar puncture to detect the presence of SAH. FLAIR MR imaging findings are infrequently positive (16.7%) when CT findings are negative for SAH. This is likely because there is a minimum concentration of RBC/cc that must be exceeded for CSF to become hyperintense on FLAIR MR images.  相似文献   
75.
The aim of this research was to evaluate, within a controlled clinical study, the effects of a Delaire-type facemask or a modified Jasper Jumper (JJ) used in the treatment of children with Class III malocclusions due to maxillary retrognathia on temporomandibular disorders (TMDs). Forty-six patients with Class III malocclusions referred for orthodontic treatment were divided into two groups, a test and a control. The test group comprised 33 randomly chosen patients (15 females, 18 males) aged 8-11 years. The control group included 13 patients (eight females, five males) with similar features. TMD assessment was performed before and after treatment using a two-axis questionnaire, the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMDs). Qualitative data were evaluated using chi-square and McNemar tests. No statistically significant differences related to the presence of TMD were observed pre- or post-treatment (P > 0.05). The most commonly encountered diagnosis was arthralgia in the JJ group both before and after treatment. Evaluation of joint and muscle regions showed decreased symptoms, apart from the diagnosed discomforts, in the JJ group (P < 0.05). Reduced symptoms were observed in the Delaire group; however, this reduction was not statistically significant. An increase, not considered to be statistically significant, was observed in the control group. The Delaire-type facemask and modified JJ used in the early phase of Class III malocclusion treatment did not result in TMD.  相似文献   
76.
Background: The aim of this study is to evaluate the levels of serum lipoprotein‐associated phospholipase A2 (Lp‐PLA2) and high‐sensitivity C‐reactive protein (hsCRP) in association with periodontal disease and hyperlipidemia. Methods: A total of 123 subjects with hyperlipidemia and 68 systemically healthy controls were included in the study. Subjects with hyperlipidemia were divided into two groups: the suggested‐diet (HD) and prescribed‐statin (HS) groups and then into three subgroups: the healthy (HDh and HSh), gingivitis (HDg and HSg), and periodontitis (HDp and HSp) groups. Periodontal parameters were recorded and included the plaque index, gingival index (GI), probing depth (PD), clinical attachment level (CAL), and percentage of sites with bleeding on probing (BOP). Fasting venous blood samples were obtained, and serum lipid, Lp‐PLA2, and hsCRP levels were evaluated. Results: Median values for the GI, PD, BOP(%), and CAL in the HSg group were statistically significantly higher than those in the HDg and systemically healthy with gingivitis (Cg) groups. The HSp group had higher percentages of BOP compared to those of the chronic periodontitis and HDp groups. The HDg group had higher serum Lp‐PLA2 and hsCRP levels compared to those of the Cg and HSg groups. The ratio of total cholesterol to high‐density lipoprotein cholesterol (TC/HDL) was significantly associated with the GI, PD, and BOP(%) in both groups with hyperlipidemia. Serum Lp‐PLA2 and hsCRP levels were significantly correlated with TC/HDL, the GI, PD, and BOP(%) in the HD group. Conclusions: Serum Lp‐PLA2 and hsCRP levels may play an important role in the association between periodontal disease and hyperlipidemia, and the control of these mediators may affect the inflammatory control of patients with hyperlipidemia and periodontal disease.  相似文献   
77.
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane.  相似文献   
78.
In patients with primary hyperparathyroidism (PHPT) not suitable for surgical correction, a skeletal protection with bisphosphonates is considered a reasonable option, but the long-term effects after treatment discontinuation are not well known. Sixty postmenopausal women with PHPT were given 400–600 IU vitamin D3 daily and 100 mg neridronate IV every 2 months for 2 years with 2 additional years of follow-up without antiresorptive therapies. Bone mineral density (BMD) progressively rose by 6.7 ± 7.6% (SD) and by 2.9 ± 4.5% at the spine and femoral neck, respectively. During follow-up, mean BMD progressively fell, but after 2 years it was still 3.9 ± 5.5% higher than baseline values at the spine. Bone alkaline phosphatase and serum C-telopeptide of type I collagen decreased significantly within 6 months (28 and 49% versus baseline, respectively) and rose to baseline values within 6–12 months during follow-up. Serum PTH significantly rose from baseline during treatment, but it remained significantly higher than baseline during follow-up. The PTH changes were significantly correlated with serum 25-hydroxyvitamin D (25OHD) levels. In conclusion, in this study we observed that in patients with mild PHPT treatment with bisphosphonates is associated with the expected changes in bone-turnover markers and that the significant increases of both hip and spine BMD are partially maintained for at least 2 years after treatment discontinuation at the vertebral site. The marked increases in serum PTH levels, particularly in subjects with low 25OHD levels, persist after treatment discontinuation and this raises the suspicion that this might reflect a worsening of PHPT.  相似文献   
79.

Study Objective

To investigate whether methylene blue, given before injection of propofol, was effective in reducing the frequency and severity of pain associated with propofol injection.

Design

Prospective, randomized, double-blinded clinical study.

Setting

Operating room of a university hospital.

Patients

90 adult, ASA physical status 1 and 2 patients undergoing elective surgery.

Interventions

Patients were randomly allocated to one of three groups of 30 patients each. Group I received 50 mg of methylene blue, Group II received 40 mg of lidocaine, and Group III, the control group, was given normal saline. All drugs were given as a 2.0 mL bolus 45 seconds before propofol administration.

Measurements

Injection pain using vocal responses, facial grimacing, arm withdrawal, tears, and questioning of the patient were noted. A 4-point scale was used for documenting pain.

Main Results

Pain frequency was 90% in the saline group, whereas the frequencies were significantly lower in the lidocaine and methylene blue groups (26.7% and 40%, respectively).

Conclusions

Intravenous pretreatment with methylene blue appears to be effective in reducing the pain during propofol injection.  相似文献   
80.
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