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1.
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   
2.
Standard peritoneal dialysate has a relatively high calcium concentration of 3.5 mEq/l. Peritoneal dialysis patients thus gain calcium from the dialysate which contributes to the risk of hypercalcemia. Dialysate with 2.5 mEq/l calcium is now available. Theoretically, using dialysate with this calcium content, calcium transfer should be negative (from the patient into the dialysate) when the patient is hypercalcemic, and positive when the patient is normocalcemic or hypercalcemic. Thus, 2.5 mEq/l calcium dialysate may allow larger doses of calcium carbonate to be prescribed. We compared calcium mass transfer (CMT) in 17 stable peritoneal dialysis patients using 3.5 and 2.5 mEq/l calcium dialysate. A solution of 2.05 l, 1.5 g/dl dextrose was dwelled for 4 hours. Calcium was measured in the drained dialysate and serum (total and ionized). Mean CMT was 0.7 +/- 0.5 mEq/exchange using 3.5 mEq/l calcium dialysate and -0.9 +/- 0.9 mEq/exchange using 2.5 mEq/l calcium dialysate (p less than 0.0001). At the time of the CMT studies, the mean serum ionized calcium levels were identical for the two groups (2.6 mEq/l). CMT correlated inversely with serum total calcium, serum ionized calcium, and drained dialysate volume. During hypercalcemia calcium transfer was from the dialysate to the patient when 3.5 mEq/l calcium dialysate was used, but from the patient to the dialysate when 2.5 mEq/l calcium dialysate was used. We conclude that 2.5 mEq/l calcium dialysate is effective in removing calcium and will be helpful in preventing hypercalcemia when large doses of oral calcium compounds are prescribed as a phosphate binder.  相似文献   
3.
Are sex offenders treatable? A research overview   总被引:1,自引:0,他引:1  
OBJECTIVE: Recent legislation in several states providing for civil commitment and preventive detention of sexually violent persons has stirred legal, clinical, and public policy controversies. The mandate for psychiatric evaluation and treatment has an impact on public mental health systems, requiring clinicians and public administrators to direct attention to treatment options. It is a common view that no treatments work for disorders involving sexual aggression. The authors examine this assumption by reviewing research on the effectiveness of treatment for adult male sex offenders. METHODS: MEDLINE was searched for key reviews and papers published during the years 1970 through 1998 that presented outcome data for sex offenders in treatment programs, individual case reports, and other clinically and theoretically important information. RESULTS: Although rigorous research designs are difficult to achieve, studies comparing treated and untreated sex offenders have been done. Measurement of outcome is flawed, with recidivism rates underestimating actual recurrence of the pathological behavior. Outcome research suggests a reduction in recidivism of 30 percent over seven years, with comparable effectiveness for hormonal and cognitive-behavioral treatments. Institutionally based treatment is associated with poorer outcome than outpatient treatment, and the nature of the offender's criminal record is an important prognostic factor. CONCLUSIONS: Although treatment does not eliminate sexual crime, research supports the view that treatment can decrease sex offense and protect potential victims. However, given the limitations in scientific knowledge and accuracy of outcome data, as well as the potential high human costs of prognostic uncertainty, any commitment to a social project substituting treatment for imprisonment of sexual aggressors must be accompanied by vigorous research.  相似文献   
4.
Chest wall hemangiomas are rare tumors that may originate within the soft tissue or from the ribs. Intramuscular hemangioma is infrequent, representing less than 1 % of all hemangiomas, and the localization in the chest wall is even less frequent. They are typically cutaneous in location, large, and poorly circumscribed and can be locally destructive. We present a case of a 34-year-old lady presented with firm lump 3 × 3 cm in left upper and inner quadrant of left breast well defined borders, non-pulsatile and restricted mobility. Sono-mammogram was suggestive of ill-defined lesion at 10 o’clock position. CT chest was conclusive of chest wall hemangioma. The patient underwent excision of the lump. HPE was suggestive of cavernous hemangioma. Cavernous hemangioma typically manifest at birth or before the age of 30 years. CT is more sensitive than plain radiography in detecting phleboliths, which are present in approximately 30 % of cavernous hemangiomas. Surgical excision would be treatment of choice. In this case, the site of the lesion was in the breast clinically mimicking that of a fibroadenoma which warrants hemangioma as a differential diagnosis.  相似文献   
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Supernumerary B chromosomes are optional additions to the basic set of A chromosomes, and occur in all eukaryotic groups. They differ from the basic complement in morphology, pairing behavior, and inheritance and are not required for normal growth and development. The current view is that B chromosomes are parasitic elements comparable to selfish DNA, like transposons. In contrast to transposons, they are autonomously inherited independent of the host genome and have their own mechanisms of mitotic or meiotic drive. Although B chromosomes were first described a century ago, little is known about their origin and molecular makeup. The widely accepted view is that they are derived from fragments of A chromosomes and/or generated in response to interspecific hybridization. Through next-generation sequencing of sorted A and B chromosomes, we show that B chromosomes of rye are rich in gene-derived sequences, allowing us to trace their origin to fragments of A chromosomes, with the largest parts corresponding to rye chromosomes 3R and 7R. Compared with A chromosomes, B chromosomes were also found to accumulate large amounts of specific repeats and insertions of organellar DNA. The origin of rye B chromosomes occurred an estimated ~1.1-1.3 Mya, overlapping in time with the onset of the genus Secale (1.7 Mya). We propose a comprehensive model of B chromosome evolution, including its origin by recombination of several A chromosomes followed by capturing of additional A-derived and organellar sequences and amplification of B-specific repeats.  相似文献   
8.

Background

Autogenous cranioplasty infection requiring bone flap removal is under-recognised as a major complication causing significant morbidity. Microbial contamination of stored bone flaps may be a significant contributing factor. Current infection control practices and storage procedures vary. It is not known whether ‘superficial’ swabs or bone cultures provide a more accurate assessment.

Method

Twenty-five skull flaps that were cryo-stored for more than 6 months were studied. Two swab samples (superficial and deep) and a bone biopsy sample were taken from each skull flap sample and cultured. Half blood agar and half chocolate agar plates were inoculated with the swabs for anaerobic and aerobic cultures respectively. The bone biopsy samples were cultured in brain-heart broth and subcultured similar to the swabs for 5 days.

Results

Incidence of microbial contamination was 20 % in the bone flaps studied. One swab culture and five bone biopsy cultures were positive for bacterial growth, all of which contained Propionibacterium acnes (p?=?0.014). Positive cultures were from bone flaps stored less than 18 months, whereas no growth was obtained from bone flaps that were stored longer (p?=?0.014).

Conclusions

Bone biopsy culture is a more sensitive technique of assessing microbial contamination of cryo-stored autogenous bone flaps than swab cultures. The clinical implications of in vitro demonstration of microbial contamination require further study.  相似文献   
9.
Covering epithelial defects in the oral cavity is often neccessary in maxillofacial surgery. Special problems arise in preprosthetic surgery because requisites for function and quality of epithelial grafts must be satisfied. Using free heterologous lyophilized dura grafts for vestibular sulcoplasty in 23 patients, we observed a good clinical and histological healing process. Considering the necessity of a second operation for skin or mucosal grafts (and the limited source of mucosa), we believe that the lyophilized dura can be used successfully in preprosthetic surgery.  相似文献   
10.
Deep brain stimulation for refractory obsessive-compulsive disorder.   总被引:7,自引:0,他引:7  
BACKGROUND: Neurosurgery (anterior capsulotomy) has been beneficial to many patients with debilitating, refractory obsessive-compulsive disorder (OCD), but the irreversibility of the procedure is an important limitation to its use. Nondestructive, electrical stimulation (deep brain stimulation; DBS) has proven an effective alternative to ablative surgery for neurological indications, suggesting potential utility in place of capsulotomy for OCD. METHODS: The effects of DBS for OCD were examined in four patients in a short-term, blinded, on-off design and long-term, open follow-up. The patients had incapacitating illness, refractory to standard treatments. Hardware developed for movement disorder treatment was surgically implanted, with leads placed bilaterally in the anterior limbs of their internal capsules. Patients received stimulation in a randomized "on-off" sequence of four 3-week blocks. Ongoing, open stimulation was continued in consenting patients after the controlled trial. RESULTS: Patients tolerated DBS well. Dramatic benefits to mood, anxiety, and OCD symptoms were seen in one patient during blinded study and open, long-term follow-up. A second patient showed moderate benefit during open follow-up. CONCLUSIONS: It appears that DBS has potential value for treating refractory psychiatric disorders, but additional development work is needed before the procedure is utilized outside of carefully controlled research protocols.  相似文献   
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