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1.
The protean manifestations of a novel maternally inherited point mutation of the mitochondrial genome are reported. The proband showed isolated, spastic paraparesis. A brother, who had suffered from a multisystem progressive disorder, ultimately died of cardiomyopathy. Another brother is healthy. The proband's mother showed truncal ataxia, dysarthria, severe hearing loss, mental regression, ptosis, ophthalmoparesis, distal cyclones, and diabetes mellitus. A muscle biopsy performed in the proband failed to show the morphological abnormalities typical of mitochondrial disorders; the activities of respiratory chain complexes were normal. However, complex I and IV activities were low in the muscle homogenate of the affected mother and brother. Sequence analysis of mtDNA showed a heteroplasmic mutation of the tRNA(Ile) gene (G4284A). The mutation load was approximately 55%, 80%, and 90% in the muscle mtDNA of the proband, his mother, and his affected brother, respectively. Mutation was undetected in the healthy brother, as well as in 100 control samples. Several cybrid clones containing homoplasmic mutant mtDNA from the proband showed significant reductions of complex IV activity and maximum oxygen consumption rate, compared with homoplasmic wild-type clones derived from the same subject.  相似文献   
2.
Using the two-dimensional Fourier transform and the brain's centroidal principal axis, a method is developed for the analysis of PET metabolic brain images without the use of predefined anatomic regions of interest. We applied the method to images from a group of 11 normal and 12 medicated schizophrenics tested under resting conditions and under a visual task. A cortical/subcortical spatial pattern was found to be significant in two directions; anterior/posterior and chiasmatic (left-anterior/right-posterior). The best individual clinical classification (Jackknife classification) occurred under visual task at two axial brain levels: at the basal ganglia with correct classification rates of 91% and 84%, while the cerebellum had rates of 82% and 92%. These high classification rates were obtained using only the four coefficients of the lowest spatial frequency. These results point to the generalized brain dysfunction of regional glucose metabolism in chronic medicated schizophrenics both at rest and at a visual image-tracking task.  相似文献   
3.
The hepatitis B virus (HBV) and hepatitis Delta virus (HDV) infection rates were estimated in patients attending a venereal disease outpatient clinic: 759 heterosexuals and 154 homosexual-bisexual men. The anti-HBC prevalence was higher in homo-bisexual men (68.8 per 100) than in heterosexuals (41.8 per 100), whereas HBsAg was roughly the same in the two groups (about 6 per 100). The anti-HBc prevalence rate among heterosexuals was higher than that estimated in hospital personnel from the same geographical area. A positive association between anti-HBc prevalence and present or past sexually transmitted diseases (STD) was found among homo-bisexual men. Anti-HBc was also positively associated with herpes simplex type 2 antibodies in both heterosexuals and homo-bisexual men. These data are consistent with the hypothesis that sexual behavior also plays a role in the spread of infection among heterosexuals. Ten of the 46 HBsAg-positive subjects were anti-HDV positive: 6 of the 36 heterosexuals and 4 of the 10 homosexuals. All HDV-positive subjects had present or past STDs. These findings suggest sexual transmission of HDV infection.  相似文献   
4.
The microvasculature of the water buffalo (Bubalus bubalis) epididymis was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo epididymis showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in the caput, corpus, and cauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo epididymis plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were many diverticula. These diverticula appear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo epididymis, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium. Anat Rec 266:58–68, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
5.
The Morpho-structural characteristics of the vallate papillae of the bovine tongue were studied utilizing LM, SEM and TEM techniques. In the bovine, the vallate papillae are numerous and different in size. They have a prominent vallum papillae which surrounds a deep sulcus papillae. The sulcus has many elongated taste buds on its inner wall. Nervous fibers enter the taste bud and sometimes have rosary shaped axons. The gustative sensitivity of these animals may be instrumental, in their choice of food and avoidance of noxious plants.  相似文献   
6.
Objectives In this case-control study we tested the hypothesis of an association between some psychosomatic skin diseases, attachment style and stress. Patients and methods A total of 177 cases and 194 controls seen between November 1992 and November 1993 at the Istituto Dermopatico dell'lmmacolata (IDD) in Rome, were enrolled into the study. Cases were outpatients with first diagnosis of hyperidrosis, chronic urticaria, generalized pruritus or alopecia areata. Controls were outpatients seen in the same period of time with first diagnosis of pigmenled nevi, keratosis or mycosis. The presence and weight of life stress events were assessed by u standard precoded questionnaire based on the Schedule of Recent Experiences (SRE) and on the Life Experiences Survey (LES). The attachment style was assessed by a modified version of the Shaver and Hazan questionnaire about feelings in a love relationship. We calculated 3 scores for each individual and classified study subjects in 2 groups: 1) "free" (= secure attachment); 2) "not free" (not secure attachment: anxious-ambivalent or avoidant). Questionnaires were self-administered in the presence of a trained psychologist. Adjusted odds ratios (OR) were calculated using a multiple logistic function. Results No association was found between the different stress scores and the skin diseases considered. The crude odds ratio for life stress events in the previous year was 1.4 (95% CI 0.8–2.7). After multiple adjustment for age, sex, marital status and education, the estimated OR was 1.6 (95% CI 0.8–3.0). One significant association emerged between the adult attachment style defined as “not free” and psychosomatic skin diseases: the adjusted OR was 4.0 (95% CI 1.4–12).  相似文献   
7.
Parents play a critical role in shaping their children’s substance use behaviors, yet few studies have examined the messages that caregivers give their adolescents about tobacco. In this study, we identify tobacco-related messages discussed by African American maternal caregivers and their adolescent daughters. Twenty-five African American maternal caregivers and their adolescent daughters participated in a video-taped discussion about tobacco. Discussions were transcribed and coded thematically. Seven themes emerged, which were grouped into tobacco-messages and communication strategies. Messages included health risks, non-health-related reasons to stop smoking, reasons people smoke, and tobacco products and marijuana. Strategies caregivers used to communicate their tobacco-related messages included sharing personal or their families’ experience with smoking, using humor, and role-playing. Finally, embedded within all of the themes, participants expressed their disapproval of tobacco use, whether it was directed at their own use, their adolescents’ use, a family members’ use, or peers’ use. African American maternal caregivers and their daughters openly talk about a variety of tobacco-related topics, and caregivers are open to sharing their own and their families’ experience with substance use. Findings also suggest that having caregivers and their adolescents participate in discussions tasks could be potentially beneficial in facilitating discussions and could identify areas in which caregivers could use help in discussing sensitive topics.  相似文献   
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9.
Introduction: The cardiovascular (CV) safety of testosterone replacement therapy (TRT) remains a crucial issue in the management of subjects with late-onset hypogonadism. The authors systematically reviewed and discussed the available evidence focusing our analysis on heart-related issues.

Areas covered: All the available data from prospective observational studies evaluating the role endogenous T levels on the risk of acute myocardial infarction (AMI) were collected and analyzed. In addition, the impact of TRT on heart-related diseases, as derived from pharmaco-epidemiological studies as well as from randomized placebo-controlled trials (RCTs), was also investigated.

Expert opinion: Available evidence indicates that endogenous low T represents a risk factor of AMI incidence and its related mortality. TRT in hypogonadal patients is able to improve angina symptoms in subjects with ischemic heart diseases and exercise ability in patients with heart failure (HF). In addition, when prescribed according to the recommended dosage, TRT does not increase the risk of heart-related events.  相似文献   

10.
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