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61.
In addition to serotonin, dopamine within the CNS is known to play a primary role in the control of ejaculation. However, whether D(2) and/or D(3) dopamine receptor subtypes mediate this effect is still unclear. In order to clarify this issue, a pharmacological competitive study using the preferential D(3) agonist 7-hydroxy-2-(di-N-propylamino)tetralin (7-OH-DPAT) alone or in combination with competitive nonpreferential or preferential D(2) and D(3) antagonists delivered intracerebroventricularly (i.c.v.) was undertaken in anesthetized rats. Urethane-anesthetized male rats were implanted into the cerebral ventricle with a cannula for i.c.v. injections, and recording electrodes were placed within the bulbospongiosus (BS) muscle to monitor BS muscle contractions, which were used as a marker for the expulsion phase of ejaculation. Following i.c.v. injection, 7-OH-DPAT induced ejaculation and rhythmic BS muscle contractions. Co-injected i.c.v. with 7-OH-DPAT, the nonselective D(2)/D(3) antagonist (raclopride), and the preferential D(3) antagonist (S(-)-N[n-butyl-2-pyrrolidinyl)methyl]-1-methoxy-4-cyanonaphtalene-2-carboxamide; nafadotride) but not the preferential D(2) antagonist ((+/-)-3-[4-(4-chlorophenyl)-4-hydroxypiperidinyl]methylindole; L 741,626) inhibited the occurrence of ejaculation and BS muscle contractions. These results suggest that i.c.v. delivery of 7-OH-DPAT does represent a pertinent model to investigate the physio-pharmacology of ejaculation. It is inferred that targeting brain D(3) receptors may provide a therapeutic approach for treating ejaculatory disorders in humans.  相似文献   
62.
Pisoni G  Moroni P  Turin L  Bertoni G 《Virology》2007,369(1):119-130
The compartmentalization of small ruminant lentivirus (SRLV) subtype A (Maedi-Visna virus) and B (caprine arthritis-encephalitis virus) variants was analyzed in colostrum and peripheral blood mononuclear cells of four naturally infected goats. Sequence analysis of DNA and RNA encompassing the V4-V5 env regions showed a differential distribution of SRLV variants between the two compartments. Tissue-specific compartmentalization was demonstrated by phylogenetic analysis in three of the four cases. In these animals colostrum proviral sequences were clustered relative to the blood viral sequences. In one goat, the blood and colostrum-derived provirus sequences were intermingled, suggesting trafficking of virus between the two tissues or mirroring a recent infection. Surprisingly, the pattern of free virus variants in the colostrum of all animals corresponded only partially to that of the proviral form, suggesting that free viruses might not derive from infected colostral cells. The compartmentalization of SRLV between peripheral blood and colostrum indicates that lactogenic transmission may involve specific viruses not present in the proviral populations circulating in the blood.  相似文献   
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In US men, the incidence of anal cancer, the primary cause of which is human papillomavirus (HPV) infection, has increased almost 3-fold in 3 decades; however, little is known about the epidemiology of anal HPV infection, especially in heterosexual men. In 2 US cities, behavioral data and anal biological specimens were collected from 253 men who acknowledged having engaged in sexual intercourse with a woman during the preceding year. On the basis of DNA analysis, overall prevalence of anal HPV infection was found to be 24.8% in 222 men who acknowledged having had no prior sexual intercourse with men. Of the men with anal HPV infection, 33.3% had an oncogenic HPV type. Risk factors independently associated with anal HPV were lifetime number of female sex partners and frequency of sex with females during the preceding month. These results suggest that anal HPV infection may be common in heterosexual men.  相似文献   
67.
The increasing aging population, the prevalence of chronic diseases and rising costs have brought about some unique health care challenge to our global society. In response to the unmet health care needs, researchers are actively seeking for innovative solutions that target for (1) prevention of diseases and (2) personalized diagnosis and treatment. It is envisaged that by taking preventive measures for health monitoring, diagnosing and treating patients with a personalized approach at an early stage of disease development, health care will be more cost effective and sustainable. The authors provide an overview of the advancements in Information and Communication Technology (ICT), and explain how some innovative health solutions, through the use of Telemedicine, can now be an opportunity for patients and their family.  相似文献   
68.
Mast cells (MCs) reside in tissues that are common targets of Candida spp. infections, and can exert bactericidal activity, but little is known about their fungicidal activity. MCs purified from rat peritoneum (RPMC) and a clinical isolate of C. albicans, were employed. Ingestion was evaluated by flow cytometry (FACS) and optical microscopy. The killing activity was assayed by FACS analysis and by colony forming unit method. RPMC degranulation was evaluated by β-hexosaminidase assay and phosphatidylserine externalization by FACS. Phagocytosing RPMC were also analyzed by transmission electron microscopy. Herein, we show that the killing of C. albicans by RPMC takes place in the extracellular environment, very likely through secreted granular components. Ultrastructural analysis of the ingestion process revealed an unusual RPMC–C. albicans interaction that could allow fungal survival. Our findings indicate that MCs have a positive role in the defense mechanism against Candida infections and should be included among the cell types involved in host-defense against this pathogen.  相似文献   
69.

OBJECTIVE:

To compare normal and delayed bone healing by measuring ultrasound conduction velocity across the bone callus.

METHODS:

A model of transverse linear and 5 mm resection osteotomies of sheep tibiae was used. Fourteen sheep were operated on and were divided into two groups of seven according to osteotomy type. The procedure was performed on the right tibiae and the intact left tibiae were used as controls. The transverse and axial ultrasound velocities were measured at 30-day intervals for 90 days, after which the animals were killed and both the right and left tibiae were resected for in vitro biomechanical analysis.

RESULTS:

Both the transverse and axial ultrasound velocities progressively increased, but the increase was smaller for the delayed union that resulted from the resection osteotomy. The mechanical resistance was higher for the normally healed tibiae that resulted from a linear osteotomy; this result closely correlated with the ultrasound velocity results. Significant differences were found for the comparisons between the intact and operated tibiae in both groups and between the groups for both the transverse and axial ultrasound velocities, but the differences were greater for the latter.

CONCLUSION:

We conclude that in vivo transverse and axial ultrasound velocities provide highly precise information about the healing state of both linear and resection diaphyseal osteotomies, but the axial ultrasound velocity most likely has greater discriminatory power. This method has the potential for clinical application in humans.  相似文献   
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