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91.
Osteocyte Apoptosis and Osteoclast Presence in Chicken Radii 0–4 Days Following Osteotomy 总被引:2,自引:0,他引:2
Clark WD Smith EL Linn KA Paul-Murphy JR Muir P Cook ME 《Calcified tissue international》2005,77(5):327-336
Osteocyte apoptosis caused by load-induced microdamage is followed by osteoclastic bone remodeling, and a causal link between
apoptosis and repair has been suggested. The objectives of the present study were to use a chick model to examine the incidence
of osteocyte apoptosis and the presence of osteoclasts during the first 96 hours following an osteotomy, prior to extensive
callus mineralization. Osteotomies were performed on the right radii of 24 chicks at 23–24 days of age. The left radii served
as controls. Radii were collected and processed at six time points following surgery (0, 12, 24, 48, 72, and 96 hours). Decalcified
bone tissue sections were stained either for apoptosis using a modified TUNEL procedure or for tartrate-resistant acid phosphatase
to identify osteoclasts in the intracortical and periosteal envelopes. The percentage of apoptotic osteocytes, as well as
osteoclast counts (n/mm or n/mm2) were quantified in four regions (0–1, 1–2, 2–4, and 4–8 mm from the site of the osteotomy; regions 1–4, respectively) in
the osteotomized radii and in the same measured areas in the control radii. Data for osteocyte apoptosis and osteoclasts in
the control limb were subtracted from the osteotomized limb data to identify differences due to surgical influence. The incidence
of osteocyte apoptosis was significantly higher at 12, 24, 48, and 72 hours versus 0 hours following osteotomy, and the response
was highest in region 1; however, there was no interaction between time and region. Intracortical osteoclast counts (n/mm2) were elevated after 48 hours, and the response was similar in all regions. The data demonstrate that osteocyte apoptosis
occurs within 24 hours in response to an osteotomy and temporally precedes an increase in osteoclast presence. Hence, osteocyte
apoptosis may play a role in signaling during the bone healing process. 相似文献
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93.
A case of primary ejaculatory failure due to prostatic damage in a 23-year-old patient is presented. This occurred secondary to Y-V operation of the bladder neck which was performed 19 years earlier. To our knowledge, this complication has not been described previously. 相似文献
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95.
Adjunctive treatment with mianserin enhances effects of raclopride on cortical dopamine output and, in parallel, its antipsychotic-like effect 下载免费PDF全文
Clinical studies indicate that adjunctive treatment with the antidepressant drug mianserin, a 5-hydroxytryptamine (5-HT)2A/C receptor antagonist and an α2- and α1-adrenoceptor antagonist, may enhance the effect of conventional antipsychotic drugs in schizophrenia, in particular on negative symptoms such as withdrawal retardation, akathisia, and some aspects of cognitive impairment. Here, we have examined the effect of mianserin in combination with the selective dopamine (DA) D2/3 receptor antagonist raclopride on conditioned avoidance response (CAR), a preclinical test of antipsychotic efficacy with high predictive validity; catalepsy, a preclinical test of extrapyramidal side effect liability; and DA output in the medial prefrontal cortex (mPFC) and the nucleus accumbens (NAC), respectively. Mianserin (5 mg/kg intraperitoneal) significantly enhanced the suppressant effect of a low dose of raclopride (0.1 mg/kg subcutaneous) on CAR without any increase in catalepsy. Administration of raclopride to rats pretreated with mianserin resulted in a large enhancement of DA output in the mPFC and, at the same time, a small but significant reduction in the raclopride-induced DA output in the NAC. These experimental results indicate that adjunctive treatment with mianserin to a typical D2 antagonist generates an atypical antipsychotic profile. 相似文献
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Hendrick RE Cutter GR Berns EA Nakano C Egger J Carney PA Abraham L Taplin SH D'Orsi CJ Barlow W Elmore JG 《AJR. American journal of roentgenology》2005,184(2):433-438
OBJECTIVE: The purpose of our study was to accurately describe facility characteristics among community-based screening and diagnostic mammography practices in the United States. MATERIALS AND METHODS: A survey was developed and applied to community-based facilities providing screening mammography in three geographically distinct locations in the states of Washington, Colorado, and New Hampshire. The facility survey was conducted between December 2001 and September 2002. Characteristics surveyed included facility type, services offered, charges for screening and diagnostic mammography, information systems, and interpretation methods, including the frequency of double interpretation. RESULTS: Among 45 responding facilities, services offered included screening mammography at all facilities, diagnostic mammography at 34 facilities (76%), breast sonography at 30 (67%), breast MRI at seven (16%), and nuclear medicine breast scanning at seven (16%). Most facilities surveyed were radiology practices in nonhospital settings. Eight facilities (18%) reported performing clinical breast examinations routinely along with screening mammography. Only five screening sites (11%) used computer-aided detection (CAD) and only two (5%) used digital mammography. Nearly two thirds of facilities interpreted screening mammography examinations on-site, whereas 91% of facilities interpreted diagnostic examinations on-site. Only three facilities (7%) interpreted screening examinations on line as they were performed. Approximately half of facilities reported using some type of double interpretation, although the methods of double interpretation and the fraction of cases double-interpreted varied widely across facilities. On average, approximately 15% of screening examinations and 10% of diagnostic examinations were reported as being double-interpreted. CONCLUSION: Comparison of this survey's results with those collected a decade earlier indicates dramatic changes in the practice of mammography, including a clear distinction between screening and diagnostic mammography, batch interpretation of screening mammograms, and improved quality assurance and medical audit tools. Diffusion of new technologies such as CAD and digital mammography was not widespread. The methods of double-interpretation and the fraction of cases double-interpreted varied widely across study sites. 相似文献
98.
The primary purpose of this research project was to translate and adapt the School Function Assessment (SFA), a standardized criterion-referenced instrument that measures school-related functional skills, for its cross-cultural use in Taiwan. The project consisted of four study phases: translation, cultural adaptation, pilot testing, and field testing for standardization. A series of rigorous procedures including the method of translation and back-translation, team consensus for cultural adaptation, and Rasch modelling techniques were used to address various dimensions of cross-cultural equivalence and psychometric properties of the translated SFA. The protocols that were developed as well as technical issues that were addressed in this project provide useful guidelines for international occupational therapists who are interested in translating and adapting instruments for cross-cultural use. 相似文献
99.
Comparison of logistic regression and neural network analysis applied to predicting living setting after hip fracture 总被引:1,自引:0,他引:1
Ottenbacher KJ Linn RT Smith PM Illig SB Mancuso M Granger CV 《Annals of epidemiology》2004,14(8):551-559
PURPOSE: Describe and compare the characteristics of artificial neural networks and logistic regression to develop prediction models in epidemiological research. METHODS: The sample included 3708 persons with hip fracture from 46 different states included in the Uniform Data System for Medical Rehabilitation. Mean age was 75.5 years (sd=14.2), 73.7% of patients were female, and 82% were non-Hispanic white. Average length of stay was 17.0 days (sd=10.6). The primary outcome measure was living setting (at home vs. not at home) at 80 to 180 days after discharge. RESULTS: Statistically significant variables (p <.05) in the logistic model included follow-up therapy, sphincter control, self-care ability, marital status, age, and length of stay. Areas under the receiver operating characteristic curves were 0.67 for logistic regression and 0.73 for neural network analysis. Calibration curves indicated a slightly better fit for the neural network model. CONCLUSIONS: Follow-up therapy and independent bowel and/or bladder function were strong predictors of living at home up to 6 months after hospitalization for hip fracture. No practical differences were found between the predictive ability of logistic regression and neural network analysis in this sample. 相似文献
100.
Context Changes in reimbursement have reduced length of stay (LOS) for patients receiving inpatient medical rehabilitation. The impact of decreased LOS on functional status, living setting, and mortality is not known. Objective To examine changes in LOS, functional status, living setting, and mortality in patients completing inpatient rehabilitation. Design Retrospective cohort study from 1994 through 2001 using information submitted to the Uniform Data System for Medical Rehabilitation. Setting and Participants Data were analyzed from 744 inpatient medical rehabilitation hospitals and centers located in 48 US states. A total of 148 807 patient records from 5 impairment groups (stroke, brain dysfunction, spinal cord dysfunction, other neurologic conditions, and orthopedic conditions) were examined. Patients mean age was 67.8 (SD, 15.8) years; the sample was 59% female and 81% non-Hispanic white. Main Outcome Measures Discharge setting, follow-up living setting, change in functional status, and mortality. Results Median LOS decreased from 20 to 12 days (P<.001) from 1994 to 2001. The proportional decrease in median LOS was greatest (42%) for patients with orthopedic conditions. Mean days to follow-up remained constant from 89 in 1994 to 90 in 2001. Functional status was clinically stable, while efficiency (functional status change divided by LOS) increased significantly (P<.001). Rates of discharge to home and living at home at follow-up remained stable, ranging from 81% to 93%. However, mortality at 80- to 180-day follow-up increased from less than 1% in 1994 to 4.7% in 2001. Conclusions Length of stay for inpatient rehabilitation decreased substantially from 1994 to 2001. Effectiveness as measured by change in functional status did not change clinically, and living setting did not change. Efficiency for functional outcomes improved but mortality at follow-up increased. 相似文献