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41.
1-Methyl-tetrahydro--carboline-3-carboxylic acid (MTCA) may cause eosinophilia-myalgia syndrome (EMS) associated with ingestion ofl-tryptophan. The distribution and excretion of MTCA were studied in rats which had received perorally a single 1.6 mg/kg dose of MTCA. MTCA concentrations in blood, kidney, liver, brain, heart, spleen, lung and gastrocnemius muscle were measured by HPLC combined with fluorometric detection. The concentration of MTCA in each organ reached a maximum at 1 h and then gradually declined. However, a significant level of MTCA still remained at 5 h, when 52% of ingested MTCA remained in the contents of the large intestine. Twenty-nine percent of the ingested MTCA was excreted in urine over the course of 24 h. A higher dose (10 mg/kg) of MTCA resulted in significant elevations in the concentrations and amounts of MTCA in the various organs. In addition, chronic treatment with a 10 mg/kg dose of MTCA for 6 weeks further increased the concentrations and amounts of MTCA in each organ. However, no histological changes were observed in any of the organs after chronic treatment. This is the first report which demonstrates accumulation of MTCA in the blood and various organs, including muscle, of rats. 相似文献
42.
Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献
43.
Pseudolesions of the liver possibly caused by focal rib compression: analysis based on hemodynamic change 总被引:2,自引:0,他引:2
Yoshimitsu K Honda H Kuroiwa T Irie H Tajima T Jimi M Masuda K 《AJR. American journal of roentgenology》1999,172(3):645-649
OBJECTIVE: The purpose of this study is to show and analyze the CT appearance of pseudolesions of the liver caused by rib compression and to discuss the possible mechanism on the basis of findings of incremental dynamic CT, CT during arterial portography, and CT hepatic arteriography. CONCLUSION: Focal compression of the liver caused by curved ribs can cause transient focal diminishment of portal venous perfusion without significantly altering hepatic arterial perfusion. Such diminishment may be observed as low-density areas on the early phase of incremental dynamic CT. 相似文献
44.
Yoshimatsu H Itateyama E Kondou S Tajima D Himeno K Hidaka S Kurokawa M Sakata T 《Diabetes》1999,48(12):2286-2291
45.
Hepatic angiomyolipoma: report of changing size and internal composition on follow-up examination in two cases 总被引:4,自引:0,他引:4
Irie H Honda H Kuroiwa T Yoshimitsu K Tajima T Jimi M Shimada M Taguchi K Masuda K 《Journal of computer assisted tomography》1999,23(2):310-313
We present two cases of hepatic angiomyolipoma in which the size and internal composition of the tumor changed during the course of follow-up study. The tissue elements composing the tumor are thought to grow or regress independently during the disease's clinical course. Radiologists should be aware that hepatic angiomyolipoma can change in size and internal composition during its natural course. 相似文献
46.
Yoshimitsu K Honda H Kuroiwa T Irie H Tajima T Jimi M Kuroiwa K Naito S Masuda K 《Journal of magnetic resonance imaging : JMRI》1999,9(4):579-585
We attempted to determine whether cytoplasmic fat in clear cell renal cell carcinoma (RCC) can be identified by chemical shift gradient-echo magnetic resonance imaging (CSI). CSI was performed for 22 clear cell RCCs and 30 other renal tumors (including 16 non-clear cell RCCs), all of which were surgically proven. Signal reduction in out-of-phase images of these tumors was retrospectively evaluated and compared. The signal loss ratio (SLR) was defined and calculated. Fat staining of specimens from 16 tumors was performed and correlated with SLR. SLR was significantly higher in clear cell RCCs than in non-clear cell RCCs (P < 0.001). There was a significant correlation between degree of fat staining positivity of the specimens and SLR (P < 0.01). When signal reduction in out-of-phase images suggested the diagnosis of clear cell RCC, correct diagnosis of this entity was made in resected renal tumors with sensitivity, specificity, and accuracy of 82%, 90%, and 87%, respectively. CSI can demonstrate cytoplasmic fat in clear cell RCCs, which helps to differentiate this entity from other RCCs. 相似文献
47.
A 12-year-old boy presented with right visual disturbance. Skull radiography and computed tomography (CT) showed an irregular deformity of the sella turcica, hypertrophic change of the dorsum sellae, and an inhomogeneously calcified mass in the sella turcica. Magnetic resonance (MR) imaging demonstrated the mass lesion filled the hypophyseal fossa, and extended to the dorsum sellae, right cavernous sinus, and right suprasellar region. The Dolenc pterional combined epidural and subdural approach was carried out. The histological diagnosis was chondroma. Sellar chondroma requires relief of the compression to the chiasm or optic nerve as soon as possible, so partial resection can still be beneficial. However, follow-up MR imaging or CT, visual examination, and control of pituitary dysfunction are required after the operation. 相似文献
48.
Kinuko Iwasa Yumi Nishiyama Momoyo Ichimaru Masataka Moriyasu Hye-Sook Kim Yusuke Wataya Takao Yamori Turuo Takashi Dong-Ung Lee 《European journal of medicinal chemistry》1999,34(12):1077
Seventeen quaternary protoberberine alkaloids related to berberine 1 were tested for antimalarial activity in vitro against Plasmodium falciparum and structure-activity relationships are proposed. The activity of the protoberberine alkaloids was influenced by the type of the oxygen substituents on rings A, C and D and the position of the oxygen functions on ring D. The position of the oxygen functions on ring D and the type of the oxygen substituents at the C-13 position (ring C) strongly influenced the activity. Shifting the oxygen functions at C-9 and C-10 to C-10 and C-11 on ring D resulted in a significant increase in the activity. Compounds bearing a methylenedioxy function at C-2 and C-3 (ring A) or C-9 and C-10 (ring D) showed higher activity than those which have methoxy groups at the same positions. Introduction of a methoxy group into the C-1 position (ring A) decreased the activity. Replacement of a hydroxy group at C-2 or C-3 (ring A) by a methoxy group led to a reduction in the activity. Displacement of a hydroxy function at C-13 (ring C) by the oxygen substituents such as OMe, OEt, OCOOEt, and OCON(Me)2 reduced the activity. In the same replacement at C-9 (ring D), the activity depended upon the type of the oxygen function. Six protoberberines displayed more potent activity than berberine 1. The activity decreased in the order: 10, 11, 17 and 18 > 7 and 8 > 1. 相似文献
49.
Epidemiological study on HIV/AIDS in Cambodia seroprevalence of HIV/STD among commercial sex workers
Ohshige K Morio S Mizushima S Kitamura K Tajima K Ito A Suyama A Usuku S Phalla T Leng HB Sopheab H Eab B Soda K 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1999,46(1):61-70
OBJECTIVE: To describe epidemiological features of HIV prevalence among female commercial sex workers (CSWs) in Cambodia, a cross-sectional study using a questionnaire study and serological tests was carried out from December 1997 to January 1998. We report the main results of the analyses of serological tests in this article. METHODS: Two hundred ninety six CSWs working in Sisophon and Poi Pet, located in northwest Cambodia, Bantey Mean Chey province, were recruited for interview based on a questionnaire on sexual behavior, and serological tests. The blood samples were examined for HIV antibody, Chlamydia trachomatis IgG antibody, TPHA, Hepatitis B surface antigen, and Hepatitis B surface antibody. The relationship between HIV and the other STD's was analyzed by using logistic regression analysis. RESULTS: The HIV seroprevalence rate was 43.9% (130 out of 296). The seropositive rate of Chlamydia trachomatis IgG antibody (C.T.-IgG-Ab) was 73.3% (217 out of 296). Logistic regression analysis showed a significant association between C.T.-IgG-Ab positive and HIV prevalence. (Odds Ratio: 5.33; 95% Confidence Interval, 2.82-10.07). CONCLUSIONS: This study suggests that the existence of Chlamydia trachomatis is closely related with HIV prevalence among CSWs in Cambodia. Other STDs may also increase susceptibility to male-to-female sexual transmission of HIV. This suggests that appropriate prevention against STDs will be needed for the control of HIV prevalence in Cambodia. 相似文献
50.
Tajima T 《Nihon Geka Gakkai zasshi》2000,101(12):833-839
At the end of the 19th century, surgical treatment of breast cancer was revolutionized by the introduction of the Halsted radical mastectomy. Haagensen, who studied under one of Halsted's students, further strengthened the foundations of the technique, and the Halsted operation became the standard radical breast cancer surgery worldwide. This may have been responsible for the persistence of this operation, particularly in Japan. Some Halstedian surgeons espoused the extended radical mastectomy or super-radical mastectomy. However, breast-conserving surgery is now becoming the most common technique. In the early 1970s breakthroughs in the understanding of the biology of breast cancer led to a new era of adjuvant therapy. Consequently current surgical management of breast cancer is no longer possible without considering other therapeutic modalities. Consistent with this change, it should be realized that the disease is no longer diagnosed at the same stage as it was at the time of Halsted. Although the ultimate patient outcome is not likely to be influenced solely by locoregional treatment, surgery will continue to be employed as the most effective treatment modality, and every effort should be made to prevent locoregional tumor spread. 相似文献