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111.
Klein AE Bauer TW Marks KE Belinson JL 《Clinical orthopaedics and related research》1999,(361):192-198
A 67-year-old woman presented with rapidly enlarging right anterior thigh mass. Clinical impression was of a primary sarcoma, but the histologic analysis of an incisional biopsy specimen showed adenocarcinoma with clear cell differentiation. Initially thought to be a metastasis, the malignant tumor appears to have arisen from extraabdominal endometriosis of the right groin. This case shows clinical, radiographic, and histologic findings that may help the orthopaedic surgeon recognize an unusual complication of extrapelvic endometriosis. 相似文献
112.
Long-term effects of finasteride on prostate tissue composition 总被引:11,自引:0,他引:11
Marks LS Partin AW Dorey FJ Gormley GJ Epstein JI Garris JB Macairan ML Shery ED Santos PB Stoner E deKernion JB 《Urology》1999,53(3):574-580
OBJECTIVES: To determine the long-term effects of finasteride treatment on prostate tissue composition; to relate these effects to clinical outcomes; and to test the hypothesis that finasteride exerts a selective or preferential action on the transition zone. METHODS: Nineteen men with symptomatic benign prostatic hyperplasia (BPH) who completed a 6-month double-blind trial of finasteride were enrolled in a 24-month open-label extension study of drug responders. Magnetic resonance imaging and prostate biopsy for morphometric analysis were performed together 70 times: at baseline (n = 19), after treatment periods of intermediate duration (6 to 18 months, n = 32), and after long-term drug treatment (24 to 30 months, n = 19). At baseline, prostate volume averaged 51 cc, of which 57% was transition zone. RESULTS: Decreases in symptom score, dihydrotestosterone and prostate-specific antigen levels, and prostate volume occurred at 6 months (P <0.01), stabilized, and were maintained without further long-term decreases. Prostate epithelium contracted progressively from baseline (19.2% tissue composition; 6.0-cc volume; 3.2 stroma/epithelial ratio) to intermediate (12.5%, 3.3 cc, and 5.6, respectively) to long-term treatment (6.4%, 2.0 cc, and 17.4, respectively, P <0.01 for all). Percent epithelial contraction was similar in the peripheral and transition zones (P = NS). The transition zone remained a relatively constant proportion (53% to 58%) of whole-prostate volume from baseline to long-term observation. CONCLUSIONS: Long-term finasteride treatment (24 to 30 months) results in a marked involution of the prostate epithelium, which continues to progress for many months after clinical effects stabilize. The effect on the epithelium is similar in the peripheral and transition zones for both morphometric and volumetric changes. Progressive contraction of the prostate epithelium appears to constitute the underlying mechanism for sustained action of finasteride. 相似文献
113.
Paulsen RD Steinberg GK Norbash AM Marcellus ML Marks MP 《Neurosurgery》1999,44(5):991-6; discussion 996-7
114.
Paulsen RD Steinberg GK Norbash AM Marcellus ML Lopez JR Marks MP 《Neurosurgery》1999,44(3):479-84; discussion 484-6
115.
116.
117.
Marks R 《Focus (San Francisco, Calif.)》1996,11(10):5-6
Oral sex continues to be a source of confusion in determining its risk for HIV transmission. Educator Dave Nimmons concludes that oral sex offers a possible, but very low, risk of HIV infection and states that much of the concern about oral sex and HIV prevention centers around two dozen cases of single occurrences of oral transmission from all over the world. Many researchers believe that knowledge about this small number of cases facilitates informed decisions about risk and demonstrates under which conditions transmission is possible. There is concern, however, that because a single case can personalize an issue, it can have a more powerful effect on an individual's imagination than a study with many participants. To reduce HIV transmission risk, researcher Paul O'Malley suggests avoiding trauma to the mouth and throat, especially vigorous or prolonged oral sex, avoiding oral sex when infections or abrasions in the mouth and throat are present, and avoiding the use of stimulant substances that dull sensation. At the Vancouver conference, there was little disagreement from a panel of experts that oral sex is an extremely low-risk activity. Researcher Traux presented results from a multivariate analysis of risk assessment data from HIV-antibody testing interviews and found that anal sex and drug use were associated with increased seroprevalence and oral sex was not. Interestingly, there was no statistically significant difference in seroprevalence rates between people who used condoms during oral sex and those who did not. The panels also discussed a recent study in which six out of seven rhesus monkeys became infected with simian immunodeficiency virus (SIV) after it was dabbed on the back of their mouths. Effective counselors and educators can work to raise consciousness about the actual risk of transmission from oral sex, determine whether an individual can increase or decrease this risk, determine the meaning of oral sex in a person's life, and the extent to which the person is comfortable taking any risk. 相似文献
118.
DJ SINGH 《Medical Journal Armed Forces India》1996,52(4):239-241
Stress fractures amongst military recruits are limited to the lower extremities; yet involvement of the shaft of the femur is unusual. Seven such cases in a series of 352 stress fractures are presented. The importance of early recognition and management is emphasized with a view to prevent bony disruption in an otherwise easily treatable condition.KEY WORDS: Fractures stress, Femoral fractures 相似文献
119.
Summary A radioimmunoassay for the semi-synthetic podophyllotoxin VP16-213 has been developed which is suitable for pharmacokinetic studies of the drug. A high titre antiserum was produced in a sheep in response to a VP16-213-BSA conjugate prepared using sodium periodate. Podophyllotoxin does not cross-react with the antiserum and VM26 cross-reacts to only a small extent (<0.6%). In the absence of a high specific activity tritium label, a radioiodinated histamine ligand was produced which was only partially displaced from antibody by native drug. VP16-213 can be measured in plasma without prior drug extraction with a theoretical limit of detection of 5–10 g/l. VP16-213 cis (picro) hydroxy acid is recognised by the antiserum to a greater extent than the drug itself. Thus, in order to eliminate any interference from the trans hydroxy acid metabolite chloroform extraction of plasma samples was carried out. 相似文献
120.
Surface marker studies were performed on "hairy cells" from 7 patients with hairy cell leukemia (HCL). Using sensitive analytic techniques including specific antisera and Fluorescence Activated Cell Sorter (FACS-1), further definition of the abnormal cell was achieved. Four different antisera were used in infestigating the cell surface characteristics of these patients: anti-p23,30, an antiserum reactive with B cells and a subset of monocytes, anti-311, which reacts only with T cells, pepsin digested anti-F(ab')2 which reacts with B cells only and pepsin digested anti-lysozyme reactive with monocytes and myeloid cells, but not with B or T cells. In all cases strong reactivity was observed with anti-p23,30 and anti-F(ab')2, but no reactivity with anti-311. Five out of the seven cases were reactive with anti-lysozyme in a pattern similar to normal monocytes. Furthermore, when cells were separated according to binding to anti-p23,30, anti-F(ab')2 and anti-lysozyme and in two cases, according to cell size, the majority of reactivity and large cells were "hairy" when examined under microscopy. In contrast, the small and nonreactive (dull cells) appeared as normal mature lymphocytes. Thus, our data supports the view that HCL cells bear in most cases B cell and monocytic membrane markers. 相似文献