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81.
Previous studies of sonograms in premenarchal girls have reported the typical ovary to be homogeneous in echogenicity, with cysts an uncommon finding, particularly in children less than 6 years old. These studies found no macrocysts (cysts greater than 9 mm in greatest length) in patients less than 11 years old. This information contradicts published pathology studies and our sonographic experience. The goal of this study was to determine the prevalence of cysts in the ovaries of premenarchal girls. The pelvic sonograms of 101 consecutive premenarchal girls between 2 and 12 years old, without known gynecologic or endocrinologic disease, were prospectively studied. One hundred fifty-five ovaries were adequately imaged in three dimensions. Ovaries were evaluated for the presence or absence of cysts (as defined by sonographic criteria), and the length of the cyst or of the largest cyst, if several were noted, was measured. Cysts were identified in 106 ovaries (68%). Cysts were seen in patients of all ages, particularly in the younger children (2-6 years old). Thirteen of the cysts, noted in 11 patients between 2 and 10 years old, were macrocysts. The typical sonographic appearance of the ovary in premenarchal girls is not homogeneous. Cysts are common in premenarchal girls between 2 and 12 years old and are the cause of the typical heterogeneous image. Macrocysts can be seen in healthy girls less than 11 years old.  相似文献   
82.
Positron emission tomography scans of nine patients diagnosed with summer seasonal affective disorder (SSAD) were compared with scans of 45 normal control subjects to investigate differences in brain glucose metabolism. All subjects performed an auditory discrimination task beginning several minutes before injection of F-18-deoxyglucose and continuing for 30 minutes after injection. Regional glucose metabolic rates were extracted from 60 rectangular regions of interest measured in five planes selected as atlas matches from 28 total slices. Statistically significant differences between patients with SSAD and normal control subjects were found in cerebral glucose metabolic rate and also in normalized regional glucose metabolic rates in the orbital frontal cortex and in the left inferior parietal lobule.  相似文献   
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Although some areas of adult ADHD knowledge remain unclear, there isa strong sense of how to proceed with diagnosis using current DSM-IV criteria as a guide. Thorough clinical interview, aided by the use of rating scales for current symptoms and collateral information about childhood from parents or siblings, forms the backbone of the assessment. The poor psychosocial outcomes of patients with ADHD. often a consequence of unrecognized,untreated disorder manifestation, also can serve as a diagnostic indicator. Diagnostic and symptom assessment scales also can be a significant helpin diagnosing and establishing the symptoms of ADHD in adults. It is important to remember that according to DSM-IV, the cardinal criteria for making the diagnosis are the presence of sufficient current symptoms and impairment in two realms (home, school/work, and social interactions). Accordingly, adult ADHD remains a clinical diagnosis, and the clinician-administered interview remains the cornerstone of diagnostic evaluation.  相似文献   
85.
Steroid 11 beta-hydroxylase deficiency is relatively frequent in Israel among North African Jews. Over a 39-year period, 38 affected individuals from 25 families were diagnosed. Nineteen families came from Morocco, and in another 2, one parent came from Morocco (80% of all parents). Demographic studies showed that most of their grandparents were born in the region of the Atlas Mountains. In Israel, the overall incidence of the disorder is estimated between 1 in 30,000 to 1 in 40,000 births, but in offspring of Moroccan Jews the ratio is 1 in 5,000 to 1 in 7,000, with an allele frequency of 1 in 70 to 1 in 84 and a carrier frequency of 1 in 35 to 1 in 42. The clinical expression is characterized by a wide range of variability in the signs of androgen and mineralocorticoid excess. Virilization in the female ranged from enlarged clitoris in the mildest forms, to markedly hypertrophied clitoris with penile urethra and fused labial-scrotal folds in the most severe forms. Hypertension causing vascular accidents and death was observed in both severe and mildly virilized patients, whereas masculinized females were sometimes normotensive. Based on historical evidence, the origin of the ancestors, and the onomastic analysis of the families surnames, we propose that the mutation of 11 beta-hydroxylase deficiency in Jews from Morocco may have originated in either the ancient Jewish settlers or the native Berber tribes who lived in the region of the Atlas Mountains in the southern region of Morocco before the destruction of the Second Temple by the Romans, in the year 70 C.E.  相似文献   
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OBJECTIVE: To determine the natural history of colonization with vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and resistant gram-negative bacilli among long-term-care facility (LTCF) residents. DESIGN: Observational cohort study. SETTING: A 355-bed LTCF with a ventilator unit and a subacute unit. PARTICIPANTS: Residents with colonization or infection with VRE, MRSA, or resistant gram-negative bacilli housed at the LTCF between December 1, 1999, and February 29, 2000. METHODS: Cultures of clinical and surveillance sites were performed at regular intervals. Charts were reviewed for clinical characteristics associated with clearance of colonization. Kaplan-Meier curves were constructed to analyze the number of days to clearance of colonization. RESULTS: Forty-nine residents had 65 episodes of colonization (27 VRE, 30 MRSA, and 8 resistant gram-negative bacilli). Eighteen (28%) of the episodes cleared. The clearance rate was 2.7 episodes per 1,000 person-days. Clearance occurred significantly more often with resistant gram-negative bacilli colonization compared with VRE or MRSA colonization (6 [75%] vs 12 [21%]; P = .007; relative risk, 4.17; 95% confidence interval, 1.26 to 11.8). There was a trend toward longer use of antimicrobial agents among residents with persistent colonization. Infections occurred most frequently with MRSA. The urinary tract was the most common site of infection. CONCLUSION: Among LTCF residents, colonization with resistant gram-negative bacilli is four times more likely to clear than colonization with VRE or MRSA. Performance of surveillance cultures at regular intervals may reduce the need for contact precautions for LTCF residents with resistant gram-negative bacilli colonization.  相似文献   
88.
Histologic and immunohistochemical properties of 53 medulloblastomas were analyzed with regard to clinical features and survival rate. No correlation was found between survival rate and histologic features of the tumor, such as desmoplastic reaction, number of mitoses, hemorrhages, necrosis, endothelial proliferation, glomerular arrangement, calcifications, rosettes, or oligodendroglial cells. However 82% of the patients with positive glial fibrillary acidic protein (GFAP) staining in numerous tumor cells survived more than 5 years; only 30% survived that long if their tumor cells were GFAP negative (P = 0.0093). This significant difference was not related to the mode of therapeutic protocol used. The authors suggest that GFAP staining may be a useful prognostic tool in medulloblastoma.  相似文献   
89.
When medical students become involved in patient care, concerns are raised that have ethical and possibly legal implications. In order to determine compliance with the guidelines of the U.S. government and the Joint Committee on Accreditation of Hospitals pertaining to informed consent, the authors conducted a study of hospital administrators, medical school department chairpersons, and medical school deans (with response rates ranging from 82.3 to 95.1 percent) concerning policies on student involvement in patient care. The results show that only 37.5 percent of all responding teaching hospitals specifically informed patients that students would be involved in care. Only 51 percent of the responding medical schools that specifically gave their students instruction or guidance on initial patient interaction as a matter of policy insisted that their students introduce themselves as students and clarify their role in patient care. The authors conclude that medical educators' compliance with the ethical requirements of informed consent is incomplete.  相似文献   
90.
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