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1.
To date, only 10 cases of distal penile gangrene in patients with chronic renal failure have been reported. This rare condition is believed to result from progressive vascular calcification due to secondary hyperparathyroidism in patients with chronic renal failure. We report an additional case of distal penile gangrene in a 41-year-old man who presented with chronic renal disease and pulmonary tuberculosis. Since some authors have emphasized that aggressive surgical treatment in such cases has a significant mortality rate, we took a more conservative approach to treatment.  相似文献   
2.
We studied 14 patients with obsessive-compulsive disorder (OCD) by positron emission tomography and the fluorodeoxyglucose method, looking for abnormalities in local cerebral metabolic rates for glucose in brain structures that have been hypothesized to function abnormally in OCD. These patients were compared with 14 normal controls and 14 patients with unipolar depression. The patients with unipolar depression and OCD did not differ in levels of anxiety, tension, or depression. In OCD, metabolic rates were significantly increased in the left orbital gyrus and bilaterally in the caudate nuclei. This was apparent on all statistical comparisons with both controls and unipolar depression. The right orbital gyrus showed at least a trend to an increased metabolic rate in all comparisons. The metabolic rate in the left orbital gyrus, relative to that in the ipsilateral hemisphere (orbital gyrus/hemisphere ratio), was significantly elevated compared to controls and subjects with unipolar depression, and stayed high even with successful drug treatment. Though it was in the normal range in the morbid state, with improvement in OCD symptoms after drug treatment, the caudate/hemisphere metabolic ratio increased uniformly and significantly bilaterally. This ratio did not increase in patients who did not respond to treatment. Thus, OCD showed cerebral glucose metabolic patterns that differed from controls in both the symptomatic and recovered states.  相似文献   
3.
Retention is a major part of orthodontic treatment, not an optional secondary protocol. In recent years, studies investigating dentofacial changes during and after the growth period have led most clinicians to use fixed retention appliances after treatment. Fixed retainers can be attached to the teeth directly or indirectly. We present a practical, indirect method for bonding fixed retainers, using Sondhi Rapid-set Indirect Bonding Adhesive (3M Unitek, Monrovia, Calif).  相似文献   
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5.
We show here that T cell cross-reactivity between heterologous viruses influences the immunodominance of virus-specific CD8(+) T cells by two mechanisms. First, T cells specific for cross-reactive epitopes dominate acute responses to viral infections; second, within the memory pool, T cells specific for cross-reactive epitopes are maintained while those specific for non-cross-reactive epitopes are selectively lost. These findings suggest an immunological paradigm in which viral infections shape the available T cell repertoire, causing alterations in the hierarchies of both the primary and memory CD8(+) T cell responses elicited by subsequent viral infections. Thus, immunodominance is a function of the host's previous exposure to unrelated pathogens, and this may have an impact on protective immunity and immunopathology.  相似文献   
6.
Leukotrienes, one of the mediators of inflammation in asthma, have a strong bronchoconstrictive effect. L-carnitine has been reported to influence respiratory functions. It has also been reported that L-carnitine inhibits leukotriene synthesis. To evaluate the effects of L-carnitine on oxygen saturation, urine leukotriene E4 levels and lung histopathology in a murine model of asthma, high IgE responder BALB/c mice (n = 24) were systemically sensitized to ovalbumin and chronically challenged with low particle mass concentrations of aerosolized ovalbumin, and then they were divided into 3 groups (study groups A, B, and C) each including eight mice. After methacholine-induced bronchoconstriction, the mice in groups A and B were given intraperitoneal L-carnitine (250 and 125 mg/kg, respectively), while the mice in group C were given placebo. Oxygen saturation of the mice was measured by pulse oxymeter before and after methacholine and after L-carnitine/ placebo application. In addition, urine leukotriene E4 levels were measured before asthma development, and 24-h after L-carnitine injection in asthmatic mice. Inflammation in the lung tissues of the sacrificed animals was scored histopathologically to determine the effect of L-carnitine on tissue level. A control group of non-sensitized mice (n = 8) treated with placebo only was used for comparison of urine leukotriene E4 levels and of histopathological parameters. Oxygen saturation of the mice in the study groups tended to decrease after methacholine and to improve after L-carnitine injection, although these changes were not significant at all time points. Urine leukotriene E4 levels of all 3 study groups increased significantly after asthma development. The rate of increment was smallest in the group given the highest L-carnitine dose (group A). Inflammation at the tissue level was also mildest in group A, and severest in the group that was not given carnitine (group C). All of the study groups and the control group differed significantly with respect to inflammation scores. In conclusion, L-carnitine improved oxygen saturation, and decreased urine leukotriene E4 levels and inflammation in lung tissues in the present murine model of asthma.  相似文献   
7.
Gynaecomastia in adolescents is a benign glandular proliferation of the male breast. Secondary causes of gynaecomastia in adolescents are relatively rare and may result from a wide variety of rare pathological conditions. Among these, klinefelter syndrome, complete androgen resistance, adrenal tumours and oestrogen-secreting testicular tumours, hypogonadism, hyperthyroidism, kidney disease and medications play a role in aetiology. The aim of our study is to review the demographic characteristics, hormone profile, aetiological characteristics of paediatric gynaecomastia patients admitted to a single center and to determine the frequency of pathological gynaecomastia. Forty-three male patients with gynaecomastia who applied to the paediatric endocrinology outpatient clinic were included in our study. Demographic characteristics, physical examination findings, hormone profile, breast ultrasonography and karyotype results of the patients were recorded. There were 43 male patients in our study. Thirty-six (83.7%) of the patients were pubertal gynaecomastia, 7 (16.2%) were pathological gynaecomastia. Three of the patients with pathological gynaecomastia were prepubertal gynaecomastia, 2 had klinefelter syndrome, 1 had hypergonadotropic hypogonadism after acute lymphoblastic leukaemia treatment and 1 had gynaecomastia after spirololactone use. Careful evaluation of patients with gynaecomastia is especially important in detecting pathological types. We reported the rare prepubertal gynaecomastia and klinefelter frequency in our study.  相似文献   
8.
Background: The wheezing infant is a common but difficult patient to approach diagnostically. The prevalence of immunoglobulin (Ig) G subclass deficiency in wheezing infants is still controversial. Methods: We studied the serum concentration of IgG subclasses in 38 wheezing infants (aged6–24 months) who had not received systemic steroids before investigation and in 30 healthy age matched controls6–31 months). Results: The prevalence of one or more IgG subclass deficiencies was 3 1.6% in wheezing infants and 26.7% in controls. There was no significant difference in prevalence of IgG subclass deficiency between patients and controls (P > 0.05). The mean concentration of IgG subclasses in patients were compared with controls. There was no significant difference in mean serum concentration of IgG1, G2 and G3 subclasses. However, there a trend towards higher concentrations of IgG4 in wheezing infants and this difference for IgG5 was significant (P < 0.01). Immunoglobulin G subclass deficiency was found in 25 and 36.4% of wheezing infants who experienced from two to four and five or more wheezing episodes in 2 years, respectively (P > 0.05). Conclusion: Our findings suggest that wheezing in infancy is not associated with IgG subclass deficiency, and in wheezing infants low IgG subclasses levels do not increase the frequency of wheezing. However, is a relationship between recurrent wheezing and serum IgG4 subclass concentration.  相似文献   
9.
Abstract

Synthetic micro/nanomotors (MNMs) are novel, self-propelled nano or microscale devices that are widely used in drug transport, cell stimulation and isolation, bio-imaging, diagnostic and monitoring, sensing, photocatalysis and environmental remediation. Various preparation methods and propulsion mechanisms make MNMs “tailormade” nanosystems for the intended purpose or use. As the one of the newest members of nano carriers, MNMs open a new perspective especially for rapid drug transport and gene delivery. Although there exists limited number of in-vivo studies for drug delivery purposes, existence of in-vitro supportive data strongly encourages researchers to move on in this field and benefit from the manoeuvre capability of these novel systems. In this article, we reviewed the preparation and propulsion mechanisms of nanomotors in various fields with special attention to drug delivery systems.  相似文献   
10.
Human kallikreins (hKs) have been reported to be involved in human cancers, and several hKs are promising biomarkers of various cancers, such as prostate, ovarian, breast, and testicular cancer. In the present study, we aimed to evaluate the prognostic value of immunohistochemical expression of hK11 in patients with gastric cancer. The study included 55 (36 men and 19 women; 58 ± 10 years of mean age) patients with gastric cancer treated with surgery and adjuvant chemoradiotherapy. Tissue sections were evaluated immunohistochemically with a monoclonal anti-hK11 antibody. Of the 55 patients, 35 (63.6%) were hK11-positive and 20 (36.4%) were hK11-negative. Disease-free and overall survival rates were significantly higher in patients with hK11 positive than in those with hK-11 negative expression (24 months vs. 11 months, p: 0.043; 29 months vs. 13 months, p: 0.038, respectively). In conclusion, hK11 expression in gastric cancer appears to be associated with a better prognosis. hK11 may be a prognostic biomarker of gastric cancer. On the other hand, it is needed to elucidate the mechanisms underlying the regulation of hK11 expression in gastric cancer.  相似文献   
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