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991.
992.
Formalin is commonly used in fixation of cadaveric specimens. Exposure to formaldehyde, a component of formalin and a known carcinogen, during gross anatomy laboratory dissection is a continuing concern for pregnant students and instructors. Since there is little literature on this specific topic, the current review was compiled in the hope of offering recommendations to pregnant students and instructors who are engaged in human anatomical dissection where formalin is used. Relevant articles were obtained through searches of PubMed and Google Scholar for the terms “formaldehyde,” “pregnant,” “formalin,” and “exposure.” A literature search was conducted for chemical information and articles about exposure as issued by government regulatory agencies and chemical companies that produce formaldehyde. This led to the compilation of 29 articles each of which included references to previous, relevant, human research. The reviewed literature contains data strongly suggesting that pregnancy can be affected by formaldehyde exposure. Therefore, on the basis our analysis, female students who might be pregnant should avoid formaldehyde exposure, including that in a gross anatomy laboratory. Instructors should find other means of ensuring anatomical competence for these students. Clin. Anat. 28:972–979, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
993.
994.
The effects of vincristine (VC) and 6-mercaptopurine (6-MP) on body weight, regional weights, and the contents of putrescine, spermidine, and spermine in six regions of the brain were examined in rats that had been given these drugs for 5 consecutive days. VC is recommended for management of tumors in the corpus striatum and/or hippocampus, and cortex although its efficacy is dependent on the doubling time of the tumor cells, whereas 6-MP is recommended for the management of tumors in the cortex, thalamus and/or hypothalamus, and diencephalon. VC and 6-MI are chosen for treatment of the brain tumors because they reduce polyamines which are associated with the reduction of drug-sensitive cells and an inhibition of tumor growth.  相似文献   
995.
996.
OBJECTIVE: To examine expression of vascular endothelial growth factor (VEGF) and thymidine phosphorylase (TP) together with microvessel count in endometrial cancer, and to investigate the relationship with clinicopathological and biological factors. METHODS: VEGF expression, TP expression, the microvessel count (factor VIII-related antigen positive cells), bcl-2 expression, proliferating cell nuclear antigen (PCNA) index, and p53 expression were determined in 50 resected endometrial cancer specimens, using immunohistochemistry. The relationship between VEGF and TP expression and correlation between expression and microvessel count were also given attention. These 3 factors were analyzed with regard to clinicopathological factors, bcl-2 expression, PCNA index, and p53 expression. RESULTS: Staining status of VEGF and TP was identical in 37 (74%) of 50 tumors, the correlation being statistically significant (p < 0.01). Combined analysis of VEGF and TP status showed that tumors which were VEGF-positive and/or TP-positive had a significantly higher microvessel count than did tumors which were both VEGF-negative and TP-negative (p < 0.001 and p < 0.05, respectively). TP expression correlated with bcl-2 expression, and VEGF expression inversely correlated with the PCNA index. Although clinical stage (p < 0.01), PCNA index (p < 0.01), and p53 expression (p < 0.01) significantly correlated with disease-free survival, neither VEGF/TP expression nor microvessel count contributed to prognostic estimates. CONCLUSIONS: VEGF and TP may cooperatively promote angiogenesis in endometrial cancer, but these expressions may have limited additional prognostic value.  相似文献   
997.
K Morita  I Takagi  M Watanabe  K Niwa  H Kanazawa 《Cancer》1985,55(11):2668-2676
In order to predict the possibility of local control of esophageal cancer by radiation therapy, the relationship between the x-ray findings before and after irradiation and the histologic radiation effect obtained from the surgically resected esophagus was analyzed in 130 cases irradiated preoperatively during the period 1971 through 1980. In the superficial or proliferative type in x-ray image before treatment, the local control was obtained in 46.5% of the cases with the dose of 40 Gy, whereas in the ulcerative or infiltrative type, in 21.8%. The barium examination performed after irradiation was more useful to evaluate the radiation effect than that before treatment. In cases with a marked radiation effect after irradiation, the frequency of local control reached 76.9%. On the other hand, the local control remained 11.9% in cases with no or poor radiation effect. The results obtained by the preoperatively irradiated cases were applied to the analysis of 119 cases irradiated radically during the period 1965 to 1980. Almost the same results were also acquired in radically irradiated cases. The degree of radiologic and histologic radiation effect on the primary tumor was closely related to the long-term survival rate of the patient.  相似文献   
998.
The Mongolian gerbil brain undergoes most of its postnatal growth and development during the first 2 weeks of life. At birth the gerbil weighs only 4% of its adult body weight, and the cerebrum and cerebellum are only 24 and 9.9%, respectively, of their adult weights. The cerebrum is more mature at birth than is the cerebellum. At 7 days of age, the cerebrum contains 55.7% of its adult DNA content, whereas the cerebellum has amassed only 17.2% of its adult content. By 21 days of age, cerebral growth is essentially complete, as measured by DNA, RNA, and protein accumulation. Cholesterol content approaches adult values in the cerebrum by 60 days of age. The rate of growth of the cerebrum and rate of RNA accumulation peak at 7 to 8 days of age. The cerebral protein velocity curve reaches its maximum at 10 to 11 days, that of DNA at 12 days, and cholesterol at 17 days of age. Conversely, the cerebellum at 21 days of age has only 65.6% of its adult protein content and 77.4% of its adult weight, although DNA multiplication is nearly complete. Myelination, as measured by accumulation of cholesterol, is not complete until sometime between 90 and 180 days of age. The velocity maxima of the other cerebellar constituents occur at about 12 to 13 days of age.  相似文献   
999.
Long-Term Course of Childhood Epilepsy with Intractable Grand Mal Seizures   总被引:1,自引:0,他引:1  
Abstract: Twenty-nine children with childhood epilepsy characterized by frequent grand mal (generalized tonic-clonic) seizures in spite of maximal doses of antiepileptic drugs and by an early onset of seizures (before 1 :year of age) were followed up for more than 5 :years. The children were divided into 3 :groups: severe myoclonic epilepsy in infancy (SME), no SME, and intractable childhood epilepsy with generalized tonic-clonic seizures (GTC). In all the 3 :groups, the grand mal seizures persisted, whereas the other types of seizures tended to disappear as the patients aged, and the prognosis for mental development was poor. In the majority of cases in all the 3 :groups, the waking grand mal seizures altered to sleep grand mal seizures with aging. Two pairs of monozygotic twins with SME suggested that genetic factors play a role in this epileptic syndrome. Intractable childhood epilepsy with GTC is distinguished by the absence of other types of generalized seizures. It cannot be regarded as an epileptic syndrome, but its pathogenesis and treatment require further studies.  相似文献   
1000.
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