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41.
Reports of the human teratogenicity of retinoids have raised concern about the potential human teratogenicity of high doses of vitamin A. Nevertheless, there are few human case reports of excess intake of vitamin A during pregnancy and defective outcomes. No epidemiological studies have been carried out on this subject. Here we present the results of an epidemiological study of prenatal exposure to high doses of vitamin A in Spain, using data from the Spanish hospital-based, case-control registry. Although it is difficult to reach conclusions with such a very low exposure level (1.3 per 1,000 livebirths), our results suggest that a teratogenic effect might exist for exposures to high doses of vitamin A (OR = 0.5, p = 0.15 for less than 40,000 FU and OR = 2.7, p = 0.06 for 40,000 1U or more). As we might expect, this effect also seems to be related to the organogenetic status (OR = 5.4, p = 0.1 for 1st –2nd month, OR = 1.8, p = 0.4 for 3rd onwards) at the time of exposure.  相似文献   
42.
43.
Two cases are presented in which conventional approaches did not permit dilation of and stent placement in obstructed ureters. In patients with iatrogenic ureteral laceration or rigid ureteral kinking, direct percutaneous translumbar puncture may provide a safe alternative. The authors' technique is described.  相似文献   
44.
SUMMARY: This report concerning the immunization of adolescents (ie, persons 11–21 years of age, as defined by the American Medical Association [AMA] and the American Academy of Pediatrics [AAP]) is a supplement to previous publications (ie, MMWR 1994;43[No. RR-1] 1–38; the AAP 1994 Red Book: Report of the Committee on Infectious Diseases; Summary of Policy Recommendations for Periodic Health Examination, August 1996 from the American Academy of Family Physicians [AAFP]; and AMA Guidelines for Adolescent Preventive Services [GAPS]: Recommendations and Rationale). This report presents a new strategy to improve the delivery of vaccination services to adolescents and to integrate recommendations for vaccination with other preventive services provided to adolescents. This new strategy emphasizes vaccination of adolescents 11–12 years of age by establishing a routine visit to their health-care providers. Specifically, the purposes of this visit are to a) vaccinate adolescents who have not been previously vaccinated with varicella virus vaccine, hepatitis B vaccine, or the second dose of the measles, mumps, and rubella (MMR) vaccine; b) provide a booster dose of tetanus and diphtheria toxoids; c) administer other vaccines that may be recommended for certain adolescents; and d) provide other recommended preventive services. The recommendations for vaccination of adolescents are based on new or current information for each vaccine. The most recent recommendations from AC1P, AAP, AAFP, and AMA concerning specific vaccines and delivery of preventive services should be consulted for details.  相似文献   
45.
Following the pioneering work of Ross and Barratt-Boyes, there is currently a strong evidence based on long-term follow-up data that valve homografts are the best valve substitutes in the aortic position. Currently there exists a renewed interest in the use of fresh and cryopreserved homografts as we know that homografts show a prolonged durability together with the lack of thromboembolic complications. Here we present the case histories of 3 patients undergoing aortic valve replacement by fresh homografts sterilized in antibiotic solution. The underlying pathology was infective endocarditis in all 3 patients, a disease that is considered the ideal indication for homograft implantation. Technical details at the time of implantation, their advantages with regard to other replacements devices and the whole process of procurement, manipulation and preservation are commented on.  相似文献   
46.
We report a case of a primary gastric Burkitt's lymphoma in a 8-year-old child, which first symptoms were abdominal pain, dysphagia, melena and a constitutional syndrome. The differential characteristics of this case are its peculiar gastric infiltration and the existence of oesophageal extension, which is very infrequent among this kind of tumors.  相似文献   
47.
Thirty patients with malignant tumours in the upper abdomen underwent surgery and intraoperalive radiation (IORT), using electron beam, to: the surgical bed, residual or unresected tumour. The technical aspects and results of this treatment are described. Renal, adrenal, bile duct and gastrointestinal tumours were treated. along with several other lesions. The surgical procedure consisted in 10 cases simply of exposure of the tumour for IORT and in 20 the tumour was resected. The TORT dose ranged from 10 to: 20 Gv. In 13 patients, external beam radiation was also given to: residual tumour or to: areas of high risk for recurrence. Chemotherapy was given to: 10 patients. Tolerance to: the combined treatment was acceptable; with few complications related to: IORT.The median follow-up and survival time 23 months (range 4-more than 70 months). Local tumour control rate (or tumour stabilisation) is 90%. Distant metastases developed in 19 patients (63%). The actuarial survival rate for the group projected at 70 months (maximum follow-up) is 37%. IORT in useful in the management of tumours arising in the upper abdominal organs, for palliation surgery or when resectability of the tumour is in doubt. Indications for IORT include patients with uncommon tumours of the upper abdomen who are not be candidates for standardised cancer treatment.Presented at the European Congress of Radiology, Vienna, September 15–20,1991  相似文献   
48.
Lung cancer is the most prevalent malignancy in western countries and most of the patients present at advanced stages, but single splenic metastasis is exceptional instead. We report on a case of a seventy-three-year old male presenting with non-hemoptoic productive cough, constitutional syndrome and pain in the left lower quadrant. Physical examination and complementary radiological and hystologycal procedures revealed the presence of an adenocarcinoma of the left lung with probable splenic metastasis. The patient underwent splenectomy, which confirmed the diagnose of splenic metastasis of lung adenocarcinoma and, secondly, lung resection was performed. Topics about lung cancer metastasis are discussed.  相似文献   
49.
Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology.  相似文献   
50.
Cast syndrome     
The term cast syndrome is used to denote duodenal obstruction occurring after application of a corrective plaster cast to patients with scoliosis. We report a classical case in a 14-year-old female who required surgical intervention after conservative treatment failed. Six months later the patient had no further gastrointestinal symptoms. Clinical, radiological, and pathological details as well as the surgical treatment are described and discussed. Offprint requests to: M. E. Martín Hortigüela  相似文献   
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