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61.
The purpose of this study was to determine whether trisomy 18 patients are at an increased risk of tumor development and require formal tumor screening recommendations. A literature search of trisomy 18 patients with reports of tumors or malignancies, and compilation of all previously reported as well as new unreported cases was performed. 67 patients with trisomy 18 were found to have documented malignancies. 44 patients had hepatoblastomas, 21 patients had Wilms tumors, one patient had a functional neurogenic neoplasia, and one patient had Hodgkins lymphoma. The increasing numbers of reported malignancies in patients with trisomy 18 supports the indication for an early screening process. Specific screening recommendations are outlined consisting of imaging exams and laboratory values performed at specific intervals.  相似文献   
62.
The University of Virginia School of Medicine has developed a student-initiated, faculty-assisted system to evaluate the faculty who teach the third-year clinical clerkships. All students complete an evaluation at the end of each clerkship, and the fourth-year class and student government compile the results and publish a detailed annual report of the data, offering constructive criticism and recommendations for change. Teaching faculty then review the report and respond to the student government, the faculty clerkship committee, and the student curriculum committee, addressing the contents of the report and initiating proposals to correct deficiencies and improve teaching. The experience of the first two administrations of this system (1988-1990) has been encouraging, and the authors suggest that the system will be applicable to the evaluation of clinical teaching on a universal basis.  相似文献   
63.
We previously reported that low levels of tyrosine (Tyr) and phenylalanine (Phe) alter the metastatic phenotype of B16-BL6 (BL6) murine melanoma and select for tumor cell populations with decreased lung colonizing ability. To more specifically characterize the effects of Tyr and Phe restriction on the malignant phenotype of BL6, we investigated in vitro attachment, invasion, proteinase expression, and chemotaxis of high and low metastatic BL6 variants. High metastatic variant cells were isolated from subcutaneous tumors of mice fed a nutritionally complete diet (ND cells) and low metastatic variant cells were isolated from mice fed a diet restricted in Tyr and Phe (LTP cells). Results indicate that attachment to reconstituted basement membrane (Matrigel) was significantly reduced in LTP cells as compared to ND cells. Attachment to collagen IV, laminin, and fibronectin were similar between the two variants. Invasion through Matrigel and growth factor-reduced Matrigel were significantly decreased in LTP cells as compared to ND cells. Zymography revealed the presence of M r 92 000 and M r 72 000 progelatinases, tissue plasminogen activator, and urokinase plasminogen activator in the conditioned medium of both variants; however, there were no differences in activity of these secreted proteinases between the two variants. Growth of the variants on growth factor-reduced Matrigel similarly induced expression of the M r 92 000 progelatinase. The variants exhibited similar chemotactic responses toward laminin. However, the chemotactic response toward fibronectin by LTP cells was significantly increased. MFR5, a monoclonal antibody which selectively blocks function of the 5 chain of the 5ß1 integrin, VLA-5, decreased the chemotactic response toward fibronectin of ND cells by 37%; the chemotactic response by LTP cells was reduced by 49%. This effect was specific for fibronectin-mediated chemotaxis since the chemotaxis toward laminin and invasion through Matrigel were not altered by the presence of MFR5. The surface expression of VLA-5 was significantly increased in LTP cells as compared to ND cells by flow cytometric analysis. These observations suggest that limitation of Tyr and Phe either directly modifies BL6 or selects for subpopulations with altered in vitro invasion, chemotaxis, and integrin expression.  相似文献   
64.
Varicocele--the most common cause of male factor infertility?   总被引:5,自引:0,他引:5  
Varicocele is often cited as the most common cause of male factor infertility. Arguments in support of this statement include reports of increased prevalence of varicocele in populations of infertile men compared with fertile or otherwise unselected men, association of varicocele with abnormal semen parameters, and improvements in semen parameters and/or pregnancy rates after varicocele repair. Logically, there would appear to be three possibilities regarding the relationship between varicocele and fertility: (i) varicocele has no association with or effect on male fertility; (ii) varicocele may be associated with, but is not the cause of, male subfertility; and (iii) varicocele is a direct cause of male subfertility. In the following, we review evidence from the literature for and against these three possibilities: at the current time, available evidence appears inadequate to confirm or deny any of these three possibilities. Since the ultimate goal of infertile couples is to conceive, it seem logical that future varicocele research should focus primarily on adequately powered, controlled clinical trials in well-characterized infertile couples, randomized to intervention or appropriate controlled observation, with pregnancy as the primary outcome.  相似文献   
65.
Lymphoma of the salivary gland accounts for 5% of cases of extranodal lymphoma and 10% of malignant salivary gland tumours. Most primary salivary gland lymphomas are B marginal zone lymphomas arising on a background of sialadenitis associated with autoimmune disorders such as Sjorgen's syndrome. Primary T cell lymphoma of the salivary gland is rare. This report describes a case of primary T cell lymphoma arising in the parotid gland of an elderly white man, which was notable for its striking resemblance to a B cell extranodal marginal zone lymphoma. Immunohistochemistry and gene rearrangement studies confirmed the clonal T cell nature of the tumour. There was no molecular evidence of Epstein-Barr virus (EBV) infection of neoplastic or surroundings cells. Only 14 cases of primary T cell lymphoma of the salivary glands have been recorded in the literature, most being from the Orient and having extremely variable prognosis. Those with a T/natural killer cell phenotype are associated with EBV infection. This case highlights the fact that T cell lymphoma in the salivary gland can mimic closely the morphological features of B cell extranodal marginal zone lymphoma.  相似文献   
66.
This study examines harmaline-induced changes in 5′-nucleotidase (5′-ND) activity in cerebellar fractions from rats with an intact inferior olive (IO) or prior destruction of the IO by 3-acetylpyridine (3-AP) intoxication. Harmaline markedly increased 5′-ND activity in the crude homogenate (P<0.05) and P2 fraction (P<0.001) of cerebella from rats with an intact IO. This increase was absent in the P1, P3 and S3 fractions and it was abolished by 3-AP olivectomy. It was also absent in basal ganglia P2 fractions. Since harmaline produces rhythmic complex spike discharges of Purkinje cells by activating IO neurons [4, 18], these data suggest that climbing fiber activation per se increases 5′-ND activity in the P2 fraction. This raises the possibility that a climbing fiber-induced local increase in 5′-ND activity at parallel fiber-Purkinje cell synapses results in a local increase in adenosine concentration. This may account for climbing fiber-evoked suppression of simple spike activity [12, 13, 28].  相似文献   
67.
Social Security spends $135 million yearly, contracting with physicians to provide consultative examinations for disability applicants. However, little is known about who these physicians are or how they view the determination of impairment. We surveyed a random sample of 153 physicians from North Carolina who performed consultative examinations for the North Carolina Disability Determinations Agency in 1983 (the consultative group), and a randomly selected group of 165 physicians of similar medical specialties (the comparison group). Response rates were 75% for the consultative group and 66% for the comparison group. Most consultative physicians (63%) performed fewer than 6 examinations per month. Characteristics of the consultative physicians were similar to the comparison group. Both groups were skeptical of the claims of disability applicants; 48% of the consultative and 55% of the comparison group thought that a majority of applicants could be employed. Of the consultative physicians, 53% indicated that they had learned little about disability programs from any source. Most consultative physicians (58%) judged it "almost impossible" to determine impairment on the basis of a single office examination. However, consultative physicians were less likely than the comparison group to view Social Security as difficult to work with (25% vs. 54%; P less than 0.01). Agencies that determine disability ask physicians to perform a task for which they feel ill prepared and have little special knowledge.  相似文献   
68.
Pancreatic resection for pancreatic and periampullary cancer between 1969 and 1975 at The Ohio State University Hospitals had an associated operative mortality rate of 30% and a morbidity rate of 80%. Transhepatic biliary decompression (THD) has been accepted as a method of preoperative risk reduction in the deeply jaundiced patient and an alternative to surgical biliary decompression. The use of preoperative THD in pancreatic and periampullary cancer was examined. Of 44 patients with bilirubin greater than 10 mg/100 ml, 17 had radical resection (THD=7, no THD=10), and 27 had palliative operation (THD=17, no THD=10). Preoperative serum bilirubin in the THD group was 7.3±1.0 compared to 16.3 ±1.5 in the no THD group (p < 0.05). Operative morbidity rate was: radical surgery: THD (40%), no THD (70%); palliative surgery: THD (18%), no THD (20%). Operative mortality rate was: radical surgery: THD (28%), no THD (60%); palliative surgery: THD (6%), no THD (0%). Catheter-related complications were minimal. Preoperative THD tends to reduce the risk of curative resection for pancreatic and periampullary cancer, but does not alter the outcome of palliative surgery. Long-term THD may be an alternative if palliative surgical biliary decompression either fails or is not technically possible in the patient with unresectable cancer.
Resumen Se ha agudizado el debate relativo al papel de la resección curativa en el tratamiento del carcinoma pancreático y periampular. Mucha de la discusión se deriva de la excesiva morbilidad y mortalidad de la pancreatoduodenectomía y de la pancreatectomía total. Las cifras sobrepasan el porcentaje de supervivencia a 5 anos en todas las series mayores, y en algunos reportes la mortalidad operatoria es igual o mayor que el porcentaje de pacientes que sobreviven un año.La resección pancreática para cáncer pancreático y periampular entre los años 1969 y 1975 en los Hospitales de la Universidad del Estado de Ohio estuvo asociada con una mortalidad de 30% y una morbilidad de 80%. La descompresión biliar transhepática (DBT) ha sido aceptada como un método de reducción preoperatoria del riesgo quirúrgico en los pacientes intensamente ictéricos y como una alternativa a la descompresión biliar quirúrgica. El uso de la DBT preoperatoria en el cancer pancreático y periampular fué analizado. De 44 pacientes con bilirrubina mayor de 10 mg/100 ml, 17 fueron sometidos a resección radical (DBT = 7, no DBT = 10), y 27 tuvieron una operación paliativa (DBT = 17, no DBT = 10). La bilirrubina sérica en el grupo con DBT fué de 7.3±1.0, comparada con 16.3±1.5 en el grupo sin DBT (p < 0.05). La siguiente fué la morbilidad operatoria: cirugía radical: DBT 40%, no DBT 70%; cirugía paliativa: DBT 18%, no DBT 20%. La siguiente fué la mortalidad operatoria: cirugía radical: DPT 28%, no DPT 60%; cirugía paliativa: DBT 6%, no DBT 0. La DBT preoperatoria tiende a reducir el riesgo de la resección curativa para cáncer pancreático y periampular, pero no modiflca el resultado de la cirugía paliativa. La DBT prolongada puede ser una alternativa si la descompresión biliar quirúrgica falla o no es técnicamente posible en el paciente con cáncer no resecable.

Résumé La résection pancréatique pour cancer périampullaire ou pour cancer du pancréas entre 1969 et 1975 à Ohio State University Hospital accuse une mortalité opératoire de 30% et une morbidité de 80%. Le drainage biliaire transhépatique (transhepatic biliary decompression: T.H.D.), en présence de ces résultats, a été employé à titre pré-opératoire pour diminuer les risques de l'intervention chez les malades très ictériques et comme alternative au drainage biliaire chirurgical.Chez 44 malades qui présentaient un taux de bilirubine supérieur à 10 mg/dl, 17 ont subi une exérèse (7 après drainage transhépatique, 10 sans drainage transhépatique), 27 ont été traités par une intervention palliative (17 après drainage, 10 sans drainage). Le taux de bilirubine pré-opératoire fut ramené à 7.3±10 chez les malades drainés alors qu'il atteignait 16.3± 1.5 chez les malades qui n'avaient pas subi de drainage préalable.La morbidité opératoire fut en cas de chirurgie radicale de 40% après drainage et de 70% en l'absence de drainage; en cas de chirurgie palliative elle fut de 18% après drainage et de 20% en l'absence de drainage. La mortalité opératoire fut en cas de chirurgie radicale de 28% après drainage et de 60% en l'absence de drainage; en cas de chirurgie palliative elle fut de 6% après drainage et de 0% en l'absence de drainage. Les complications du drainage sont très rares. En un mot le drainage biliaire pré-opératoire réduit les risques de l'exérèse des cancers pancréatiques et des cancers périampullaire mais elle est sans influence en cas d'intervention palliative. Le drainage biliaire transhépatique prolongé offre une alternative au drainage chirurgical lorsque celui-ci échoue ou quand le cancer ne peut être réséqué.
  相似文献   
69.
COVID-19 has exacerbated pre-existing difficulties children and adults with disability face accessing quality health care. Some people with disability are at greater risk of contracting COVID-19 because they require support for personal care and are unable to physically distance, e.g. those living in congregate settings. Additionally, some people with disability have health conditions that put them at higher risk of poor outcomes if they become infected. Despite this, governments have been slow to recognise, and respond to, the unique and diverse health care needs of people with disability during COVID-19. While some countries, including Australia, have improved access to high-quality health care for people with disability others, like England, have failed to support their citizens with disability. In this Commentary we describe the health care responses of England and Australia and make recommendations for rapidly improving health care for people with disability in the pandemic and beyond.  相似文献   
70.
BackgroundThis study examined whether adverse childhood experiences (ACEs) are associated with increased risk of having an unwanted or mistimed pregnancy.MethodsWomen in two medical centers within an integrated health system were screened for ACEs during standard prenatal care (N = 745). Multinomial multivariable logistic regression analyses examined the associations of ACEs (count and type) with pregnancy intentions, adjusting for covariates.ResultsOverall, 58.3% of pregnant women reported no ACEs, 19.1% reported one ACE, and 22.7% reported two or more ACEs; 76.2% reported wanting to get pregnant, 18.5% reported wanting to get pregnant but not at this time (i.e., mistimed pregnancy), and 5.2% reported not wanting to get pregnant at all (i.e., unwanted pregnancy). Having two or more (vs. 0) ACEs was associated with higher odds of an unwanted pregnancy (odds ratio, 2.60; 95% confidence interval, 1.19–5.68). Further, childhood loss of parent (odds ratio, 2.20; 95% confidence interval, 1.03–4.71) and neglect (odds ratio, 5.67; 95% confidence interval, 1.72–18.72) were each associated with higher odds of an unwanted pregnancy in separate analyses. ACEs count and type were not significantly associated with having a mistimed pregnancy.ConclusionsAmong women screened for ACEs during standard prenatal care, ACEs were associated with increased odds of having an unwanted pregnancy, but not a mistimed pregnancy. Additional research is needed to better understand the mechanisms through which ACEs and other individual, social, and contextual factors impact pregnancy intentions to better support women and provide appropriate resources to help prevent unintended pregnancies.  相似文献   
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