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21.
Ovarian cancer marker CA 125 was measured in human seminal plasma,and the concentrations ranged between 22 and 1149 U/ml, andbetween 39 and 4711 U/ejaculate. This very high patient-to-patientvariability was in contrast to a much lower within-patient variability,which was comparable to that of other semen parameters. No significantdifferences in CA 125 concentration were found in seminal plasmafrom normospermic patients, patients with male factors, vasectomizedmen, and in aliquots of samples which led to a pregnancy, viaartificial insemination or in-vitro fertilization. The seminalplasma CA 125 concentration was not correlated with sperm count,motility and morphology. In contrast, seminal plasma CA 125concentrations correlated with the age of the patient (P <0.001) and inversely with the volume of the ejaculate (P <0.001). These correlations were independent of each other. CA125 did not correlate with the prostatic marker zinc, but diddo so with the seminal vesicle marker fructose and the epididymalmarker carnitine.  相似文献   
22.
Controlling the sex of offspring by the separation of X and Y chromosome-bearing spermatozoa using flow cytometry has been reported as a clinical technique aiding prevention of X-linked diseases. Although this technique has resulted in several hundred normal births in animals and at least one human birth, there is still concern over its genetic safety due to the involvement of two potentially mutagenic agents: UV light and the fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly those considered abnormal, may be more likely to suffer DNA damage following exposure to mutagenic agents, compared with other mammalian species. The stability of normal fresh and decondensed human spermatozoa were examined after exposure to a range of levels of UV and H33342 staining, using an assay that detects endogenous nicks in the DNA of spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed human spermatozoa was examined following UV laser, H33342 staining and flow cytometry treatments utilizing the same assay. There was an increase in the presence of endogenous nicks when spermatozoa were decondensed compared with fresh spermatozoa. There was no increase in the incidence of nicks in any group of spermatozoa after UV and fluorochrome exposure compared with controls without exposure.   相似文献   
23.
Freeny  PC; Marks  WM 《Radiology》1986,160(3):613-618
Bolus dynamic and delayed computed tomographic (CT) scans of the liver were evaluated in 43 patients with 54 hepatic hemangiomas and 111 patients with primary or secondary malignant hepatic neoplasms. Twelve patterns of contrast enhancement were recognized during the bolus dynamic phase and delayed scanning. A "typical" CT pattern for hemangiomas (present in 29 of 54 hemangiomas [53.7%]) was established: (a) diminished attenuation prior to intravenous contrast medium administration (excluding lesions arising in a liver with diffuse fatty infiltration), (b) peripheral contrast enhancement during the bolus dynamic phase, and (c) complete isodense fill-in on delayed scan images. Using these criteria, we distinguished hemangiomas from malignant neoplasms in most patients. Only one of 63 (1.6%) malignant neoplasms manifested these typical CT criteria of hemangioma. There is an 86% chance that a lesion with the typical CT appearance of hemangioma is actually a hemangioma, even when found in a patient with a known nonhepatic primary neoplasm.  相似文献   
24.
The tumor promoting agent TPA (phorbol ester; 1.6 X 10(-8)M) was used to induce the differentiation in vitro of B-chronic lymphocytic leukemia (B-CLL) cells from 14 untreated patients. The uninduced phenotype was SIg+, Mrbc+, RFT-1+, RFA-4-, FMC7-. After 72 h incubation with TPA, B-CLL cells became RFA-4+, FMC7+ and lost the capability of Mrbc rosetting. Large proportions of the "induced" cells also showed morphological and ultrastructural changes, such as undulating membranes and bleblike protusions and became strongly positive for tartrate resistant acid phosphatase (TRAP+) and also contained cytoplasmic immunoglobulins. These features are very similar to the features of hairy cell leukemia (HCL). These observations confirm previous clinical findings that B-CLL and HCL are related disorders of the B lineage. The development of "hairy" features in induced B-CLL and in HCL seems to be a malignancy-associated feature because the Mrbc+ normal B cells (B-CLL-equivalent cells) isolated from tonsil also develop TRAP positivity but no membrane aberrations.  相似文献   
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26.
目的:探索湿阻中焦证的病理机制,并探讨平胃散对湿阻中焦证的作用机理。方法:选用湿阻中焦证大鼠模型,给予平胃散配伍利水药,观测各组大鼠血浆抗利尿激素(ADH)的浓度及红细胞内电解质Na~+、K~+浓度。结果:湿阻造模组大鼠与正常组相比ADH显著升高(P<0.01);细胞内的Na~+增高,K~+显著降低(P<0.05)。给予平胃散后,高、中、低剂量组及加泽泻组大鼠ADH基本恢复正常;细胞内的Na~+下降至接近于正常,K~+尤明显变化;不造模给药组与正常组比较ADH显著升高(P<0.05),Na~+、K~+明显下降(P均<0.01)。结论:(1)血浆ADH浓度升高、细胞内Na~+增多、K~+降低在湿阻中焦证形成中起重要作用。(2)平胃散治疗湿阻中焦证的作用机理与调节ADH和细胞内Na~+、K~+浓度有关,且可能存在双向调节机制。  相似文献   
27.
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy, MATERIALS & METHODS: We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis. RESULTS: The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis. CONCLUSION: Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.   相似文献   
28.
OBJECTIVE: To provide centiles for birth weight (BW) according to gestational age (GA) and sex for infants born in Italy. METHODS: We used records of the whole neonatal population of Tuscany, a region in Italy, from July 1991 to June 2002 as resulting from the database of the cystic fibrosis neonatal screening program (n=290129). We excluded as unlikely for GA those BW that were more than two interquartile ranges above the 75th centile or below the 25th centile for each GA and gender group. RESULTS: We present the 3rd, 10th, 25th, 50th, 75th, 90th and 97th centiles of BW for GA from the 24th to 43rd week of gestation for male and female Italian neonates, as both tables and smoothed curves. CONCLUSIONS: The large size of the examined population allows us to provide up-to-date, reliable BW for GA centiles for Italian newborns, especially for lower GAs.  相似文献   
29.
We report the case of a 30-year-old woman with cystic fibrosis (CF) chronically infected with Pseudomonas aeruginosa who delivered and breast-fed a healthy boy. While breast-feeding the woman had to undergo an i.v. antibiotic course with tobramycin, due to pulmonary exacerbation. Tobramycin was not detected in her milk and lactation could be continued. This is the first time that the presence of tobramycin in the milk of a CF woman during i.v. administration has been investigated.  相似文献   
30.
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