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The external genitalia of one perimenarcheal and five adult female white handed-gibbons (Hylobates (H.) lar) were examined to clarify their gross anatomy. It was found that the vulval structures were complex and exhibited inter-individual variation in arrangement. This complexity appears to result from an ontogenetic process by which the tissues of the vaginal rim (the labia minora) bud-off and extrude extensions toward the vagina immediately prior and subsequent to menarche. Two of these lobular structures surround the urethral meatus with associated prepuce and frenulum and vestigial labia majora, undergo cycles of tumescence and detumescence during intermenstrual intervals. The complex form of the external genitalia and the presence of a swelling cycle are unusual for a monogamous species, are contrary to current applications of sexual selection theory, and raise questions about the significance of mate choice in hominoid evolution.  相似文献   
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BACKGROUND: Limited knowledge exists regarding the neurobiology of trichotillomania (TTM). Cerebellum (CBM) volumes were explored, given its role in complex, coordinated motor sequences. METHODS: Morphometric magnetic resonance imaging (MRI) scans were obtained for 14 female subjects with DSM-IV diagnoses of TTM and 12 age-, education-, and gender-matched normal control (NC) participants. Parcellation was performed utilizing a recently developed methodology to measure subterritory volumes of the CBM. Regions were defined based on knowledge of the structural and functional subunits of the CBM. RESULTS: As predicted, significant group differences were reported for CBM raw cortical volumes (p = .008) that survived correction for total brain volume (TBV; p = .037) and head circumference (HC; p = .011). A priori and post hoc group raw volume comparisons for CBM subterritories and functional clusters revealed many significant differences. However, most differences failed to withstand correction for total CBM volumes (TCV). Smaller volumes were consistently reported for the TTM versus NC cohorts. Total Massachusetts General Hospital Hair Pulling Scale (MGHHPS) scores were significantly inversely correlated with left primary sensorimotor cluster volumes (p = .008), with smaller volumes associated with more severe TTM symptoms. CONCLUSIONS: These findings implicate the CBM in the neurobiology of TTM, with reduced subterritory volumes reported for the TTM versus NC groups.  相似文献   
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Laparoscopic surgery is gaining popularity among the surgical community. While its prevalence expands, the need for reliable training and assessment tools is becoming increasingly important. Laparoscopic skills are not an innate behavior, nor can they be easily mimicked, and can only be acquired through hands-on training. A consensus exists among physicians that establishment and evaluation of technical skill in surgical training programs are inadequate and in need of improvement. A validated, reliable bench model that could train and assess could be standardized and provide numerous benefits including determination of which medical students should consider a career in surgery, valuable feedback to residents, a tracking mechanism of resident performance, a possible certification and recertification tool, and to allow for interinstitutional comparison. To this end, several potentially successful bench models testing dexterity, hand-eye coordination, and depth perception have been developed. A few models have been proven to be both valid and reliable indicators of technical skill. Although the future remains uncertain, enough groundwork has been laid to begin incorporating technical skill training and assessment into surgical training programs.  相似文献   
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A 59-year-old man developed a lower respiratory tract infection 10 years after orthotopic cardiac transplantation. He did not respond to broad-spectrum antibiotic and antifungal treatment. Parainfluenza virus type 3 was the causative organism, and he was successfully treated with intravenous ribavirin and methylprednisolone.  相似文献   
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Evaluation and management of abdominal pathology in patients with ventricular assist devices is likely to become increasingly important as the utilization of these devices expands. Ventricular assist devices represent a class of intracorporeal or paracorporeal mechanical devices that augment cardiac output in patients with congestive heart failure. Patients with ventricular assist devices supporting both right and left ventricles (biventricular assist devices) are uniquely challenging to the general surgeon because these devices restrict direct access to the abdominal cavity and because of the perioperative implications of biventricular heart failure. We describe herein the first reported successful laparoscopic cholecystectomy in a patient with a paracorporeal biventricular assist device. Cholecystectomy was performed in this patient for acute cholecystitis that occurred while the patient was awaiting heart transplantation. Our results add weight to the small body of evidence that laparoscopy is well tolerated in ventricular assist devices patients. The unique aspects of the biventricular assist device patient make laparoscopic abdominal intervention particularly suitable in this patient population.  相似文献   
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