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OBJECTIVE: To evaluate surgical outcomes for the treatment of posterior fossa meningiomas at the House Ear Clinic from 1987 to 2001. We review our current treatment algorithm and present our postoperative outcomes with attention to facial and auditory neural preservation. STUDY DESIGN: Retrospective review. SETTING: Tertiary care center. PATIENTS: Medical records of 71 patients who underwent posterior fossa meningioma surgery at the House Ear Clinic were reviewed. INTERVENTION: All patients had surgical removal of their meningioma via translabyrinthine, transcochlear, retrosigmoid, extended middle fossa, or combined petrosal approaches by House Ear Clinic neurotologists and neurosurgeons. MAIN OUTCOME MEASURES: Preoperative and postoperative auditory and facial nerve function data were collected. Patient and tumor characteristics including presenting symptoms, completion of tumor resection, and complications secondary to surgery were also recorded. RESULTS: The most common presenting symptoms in this series were otologic, with hearing loss (61%), tinnitus (58%), and imbalance (58%) as the three most common. Gross total resection was achieved in 67 (94%) patients. Hearing-preservation surgery was attempted in 37 (52%) patients (68% via extended middle fossa or combined approach). Twenty-one patients with preoperative Class A hearing had follow-up audiometric data and 18 (86%) had serviceable hearing preserved. Excluding transcochlear craniotomies, 85% of patients had normal facial nerve function postoperatively. Cerebrospinal fluid leak (6%) was the most common complication. CONCLUSIONS: Advances in microsurgical techniques have greatly changed our management of patients with posterior fossa meningiomas. These changes have reduced postoperative morbidity. Specifically, use of the anterior and posterior petrosal approaches has facilitated facial and auditory neural preservation while not compromising the extent of tumor excision.  相似文献   
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Forensic handwriting examination involves the comparison of writing samples by forensic document examiners (FDEs) to determine whether or not they were written by the same person. Here we report the results of a large-scale study conducted to assess the accuracy and reliability of handwriting comparison conclusions. Eighty-six practicing FDEs each conducted up to 100 handwriting comparisons, resulting in 7,196 conclusions on 180 distinct comparison sets, using a five-level conclusion scale. Erroneous “written by” conclusions (false positives) were reached in 3.1% of the nonmated comparisons, while 1.1% of the mated comparisons yielded erroneous “not written by” conclusions (false negatives). False positive rates were markedly higher for nonmated samples written by twins (8.7%) compared to nontwins (2.5%). Notable associations between training and performance were observed: FDEs with less than 2 y of formal training generally had higher error rates, but they also had higher true positive and true negative rates because they tended to provide more definitive conclusions; FDEs with at least 2 y of formal training were less likely to make definitive conclusions, but those definitive conclusions they made were more likely to be correct (higher positive predictive and negative predictive values). We did not observe any association between writing style (cursive vs. printing) and rates of errors or incorrect conclusions. This report also provides details on the repeatability and reproducibility of conclusions, and reports how conclusions are affected by the quantity of writing and the similarity of content.

Forensic science is under scrutiny, particularly for pattern-based disciplines in which source conclusions are reported. The National Research Council report Strengthening Forensic Science in the United States: A Path Forward (1) stated that “The scientific basis for handwriting comparisons needs to be strengthened” and noted that “there has been only limited research to quantify the reliability and replicability of the practices used by trained document examiners.” The President’s Council of Advisors on Science and Technology (PCAST) report Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods (2) expressed concerns regarding the validity and reliability of conclusions made by forensic examiners, and called for empirical testing: “The only way to establish the scientific validity and degree of reliability of a subjective forensic feature-comparison method—that is, one involving significant human judgment—is to test it empirically by seeing how often examiners actually get the right answer. Such an empirical test of a subjective forensic feature-comparison method is referred to as a ‘black-box test.’” The National Commission on Forensic Science also called for such testing (3). Although the accuracy and reliability of conclusions made by forensic document examiners (FDEs) have been the focus of multiple studies over the years (410), the designs of those studies are notably different from this study (and from PCAST’s recommendations), and therefore the resulting rates are not directly comparable (in particular, when comparing open-set to closed-set studies, comparing studies based on one-to-one vs. one-to-many examinations, and comparing studies that use notably different conclusion scales; see SI Appendix, Appendix B for a summary).This study was conducted to provide data that can be used to assess the scientific validity of handwriting comparisons, for use by policy makers, laboratory managers, the legal community, and FDEs. This study follows the approach used in the previous FBI Laboratory–Noblis latent print black box study (11) and later recommended by the PCAST report. The design utilizes open-set, one-to-one document comparisons to evaluate the conclusions reached by practicing FDEs when comparing writing samples selected to be broadly comparable to casework. The primary purposes of the study are to measure the accuracy of conclusions by FDEs when comparing handwriting samples and to assess reliability by measuring the reproducibility (interexaminer variability) and repeatability (intraexaminer variability) of those conclusions. Secondary purposes include reporting any associations between the accuracy of the decisions in this study, factors related to the participants (such as training or experience), and factors related to the samples (such as quantity of writing, comparability of content, limitations, or style of writing).  相似文献   
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OBJECTIVE: To compare the size of the genital hiatus in women wearing a pessary for pelvic organ prolapse after consistent pessary use, describe characteristics of patients who continue use, and assess change in pelvic floor symptoms. METHODS: This was an observational cohort study of 90 women seeking nonsurgical management of symptomatic prolapse. Our primary outcome was change in genital hiatus (in centimeters) after 3 months of consistent pessary use. Pelvic floor symptoms were assessed with the Pelvic Floor Distress Inventory. Change in genital hiatus measurements and Pelvic Floor Distress Inventory scores were assessed using a paired Student t test. Between-group differences were evaluated using the Student t, Mann Whitney U, and Fisher exact tests, where appropriate. Logistic regression was used to assess baseline characteristics predictive of continued pessary use. RESULTS: The average (+/-standard deviation) age of participants enrolled was 62.8 +/-13.2 years. Median parity was 3, and 87.7% were postmenopausal. Forty-two (47%) continued pessary use at 3 months. After 2 weeks, there was a decrease in the size of the genital hiatus measured with strain from 4.8+/-1.6 cm to 4.1+/-1.2 cm, P<.001, which persisted at 3 months (3.9+/-1.1 cm, P<.001). The greatest change occurred with the Gellhorn pessary. Baseline Pelvic Organ Prolapse Quantification system point Aa was positively associated with continued pessary use at 3 months, and perineal body at rest was negatively associated. CONCLUSION: After 3 months of pessary use, genital hiatus size decreased significantly. Pessary use results in significant anatomic changes to the genital hiatus in patients with pelvic organ prolapse.  相似文献   
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Tuberoinfundibular peptide of 39 residues (TIP39)-immunoreactive (IR) neurons are present in the medial subdivision of the parvocellular subparafascicular thalamic nucleus (mSPFp) where ejaculation-specific Fos expression is localized. The mSPFp is reciprocally connected to the medial preoptic area (MPOA), bed nucleus of the stria terminalis (BNST) and the medial nucleus of the amygdala (Me), all of which are critical for the regulation of male sexual behavior. The mSPFp also receives galanin and enkephalin containing projections from a region in the lumbar spinal cord, thought to be a central ejaculation center. Therefore, we hypothesized that TIP39 neurons in the mSPFp may be part of the neuronal circuitry activated by male sexual behavior. To test this hypothesis, we examined induction of Fos in TIP39 containing neurons in the mSPFp following male sexual behavior. Mating-induced Fos expression was evaluated in sexually experienced male rats under four experimental conditions: animals that (1) remained in their home cage without any interaction with females, (2) interacted with stimulus females and displayed intromission without ejaculation, (3) displayed one ejaculation, or (4) displayed 2 ejaculations. We found that Fos was induced in TIP39-IR neurons in the mSPFp in male rats following ejaculation but much less so following intromission without ejaculation. This suggests that TIP39-IR neurons in the mSPFp are part of the afferent circuits that process genital-somatosensory information related to ejaculation, and which contribute to mating and mating-induced changes in reproductive behavior.  相似文献   
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