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131.
A method of direct freezing is described which requires a cryoprotective medium consisting of human AB serum and DMSO, an ultra-low temperature freezer and a liquid-nitrogen refrigerator. Fresh and directly frozen cells were compared in the LDA assay. Direct freezing is quite reliable for normal lymphocytes, PHA transformed lymphocytes or leukaemic blasts used as targets. However, a controlled freezing procedure may be necessary to preserve the effector cell activity.  相似文献   
132.
Several Fmoc-amino acids have been esterified by use of N,N-dimethylformamide dineopentyl acetal ( 2 ) to 2,4,5-trichlorophenyl 3‘-(4“-hydroxymethyl-phenoxy)propionate ( 7 ), and the resultant handle derivatives ( 5 ) were purified and then quantitatively coupled onto aminomethyl supports. Compared to literature methodology, the present procedure is preferred because: (i) extra steps to selectively protect and liberate the carboxyl of the handle are circumvented; and (ii) the additional methylene group spacer reflecting substitution of a propionyl group for an acetyl group in the handle changes the electronic parameters of the resultant p-alkoxybenzyl ester sufficiently so that the rates of acidolytic cleavage of the anchoring linkage are 2- to 3-fold increased and useful improvements in yields can be achieved.  相似文献   
133.
Thirteen of 16 patients with primary cancer of the liver were heavy alcoholics. Fifty per cent of them had positive alpha-fetoprotein and 25% had HB-Ag in their blood. The association of alcoholism with cancer of the liver is thus very striking and hence alcohol should be proclaimed as a carcinogenic substance.  相似文献   
134.
Two cases of rapidly progressive fatal liver disease in females after by-pass surgery for obesity are reported. Histologically the livers are similar to the florid cirrhosis of the alcoholic described by Popper and Szanto. It is postulated that the nutritional disturbance, including protein deficiency, and large amounts of fatty acids delivered to the liver from the fat depots, results in fatty metamorphosis, the Mallory bodies and finally cirrhosis. Bacterial toxins from the excluded loop of intestine may contribute to this process.  相似文献   
135.
PROBLEM: The lack of expression of HLA antigen on immature germ cells from ejaculates with antisperm antibodies has been reported. METHOD: The expression of human leukocyte antigens on immature germ cells from ejaculates with antisperm antibodies (ASA) was investigated by indirect immunofluorescence using a panel of monoclonal antibodies (MAb) and automated flow cytometry. Patients were divided into two groups: fertile (prevasectomic; N= 10), and ejaculates with ASA (10 samples with IgG and IgA ASA, and five semen samples with only IgG ASA). ASA were detected on sperm using the direct immunobead test. After centrifuging semen samples on a Ficoll-Hypaque gradient, round cells obtained at the gradient interface were gated by a flow cytometer. The “immature germ cell window” was defined in terms of cellular volume and granularity. RESULTS: The percentage of gated round cells from semen samples that reacted with anti-CD45 was always less than 5%, and with anti-CD44 less than 3%. This lack of reactivity of gated round cells with MAb specific for leukocytes and epithelial cells suggests that they were immature germ cells. Immature germ cells were unreactive with W6/32 and anti-β-2-microglobulin MAb, which suggests that these cells do not express HLA class I molecules. Similarly, no reactivity of the immature germ cells with the MAb that recognize HLA class II molecules was found. No significant differences were observed in the expression of HLA molecules on immature germ cells between the different semen samples studied: fertile, and ejaculates with ASA. CONCLUSION: The presence of ASA in ejaculate is not associated with abnormal HLA antigen expression on immature germ cells.  相似文献   
136.
PURPOSE: Recent data imply that 3-dimensional (D) p53 protein modeling provides more specific information on its function in patients with pancreatic adenocarcinoma. In addition to immunohistochemical and single strand conformational polymorphism analysis, we performed 3-D p53 protein modeling and correlated our results with the disease-free survival of patients with muscle invasive transitional cell carcinoma of the bladder who underwent surgery. MATERIALS AND METHODS: We identified 43 patients and analyzed p53 status in each by immunohistochemical testing, single strand conformational polymorphism and DNA sequencing with 3-D protein modeling. Median followup was 38 months (range 4 to 92). The results of each analysis were compared and correlated with cancer specific survival. Statistical analysis was performed using the log rank test on Kaplan-Meier survival curves. RESULTS: The population included 30 men and 13 women 35 to 84 years old (median age 65). Nuclear over expression of p53 protein was observed in 26 of the 43 cases (60%). Lymph node involvement did not correlate with p53 over expression. Significantly more patients with lymph node metastasis died of cancer. Median survival in the 26 patients with p53 over expression was 28 months versus 57 in those with negative staining (p = 0.25). Mutation analysis by single strand conformational polymorphism revealed no abnormality in 24 patients (56%) with a median survival of 28 months, whereas we noted abnormal mutational analysis in 19 (44%) with a median survival of 38 months (p = 0.33). Of 19 single strand conformational polymorphism positive cases DNA sequencing showed mutation near the DNA binding site in 10 (53%), mutation away from the site in 6 (32%) and no mutation in 3 (17%). No survival difference was detected in cases with mutation away and near the DNA binding site, respectively (p = 0.69). CONCLUSIONS: In this group of patients treated with radical cystectomy for muscle invasive bladder transitional cell carcinoma, analysis of p53 protein and the p53 gene by immunohistochemical testing, single strand conformational polymorphism and mutational analysis did not correlate with cancer specific survival.  相似文献   
137.
Syntheses of cyclic kinin analogues with different backbone atom numbers are described. Cyclization, by either the O-benzotriazolyl-N, N, N', N'-tetramethyluronium tetrafluoroborate/1-hydroxybenzotriazole/diisopropylethyl amine (TBTU-HOBt-DIPEA) or the diphenylphosphoryl azide (DPPA) procedure of linear peptides prepared by the solid-phase method based on the g-fluorenyl methyloxycarbonyl chemistry, was used for preparing cyclo-Gly-Ile-Ile-Gly-bradykinin, cyclo-Lys-kallidin (cyclo-Lys-Lys-bradykinin) and cyclo-des Arg-bradykinin. Peptides were characterized by amino acid analysis, optical rotation, analytical high-performance liquid chromatography and matrix-assisted laser desorption ionization-time flight mass spectrometry. Pharmacological experiments showed that cyclo-Gly-Ile-Ile-Gly-bradykinin (39 backbone atoms) and cyclo-Lys-bradykinin (30 backbone atoms) are about equipotent, when tested on the relaxation of the isolated rat duodenum preparation. The potency of cyclo-des Arg-bradykinin is at least three orders of magnitude lower. The potency of cyclo-Lys-Lys-bradykinin (33 backbone atoms) is one tenth the activity of bradykinin but about 10 times higher than the potency of the above-mentioned cyclokinins and makes the latter analogue the most potent end-to-end cyclic analogue known currently. The present results, in agreement with data from earlier reports, seem to indicate that the enhancement of the number of backbone atoms in the cyclic kinins first increases and subsequently decreases the potency, whereas a reduction in the atom number from 27 to 24 causes a dramatic decrease in potency.  相似文献   
138.
Partial small bowel obstruction developed in a patient with associated giant sigmoid diverticulitis. This complication resulted from the wall of the diverticulum adhering to a loop of terminal ileum. Small bowel obstruction had not been observed in the 15 cases of giant sigmoid diverticula reported in the literature.  相似文献   
139.
Malignant rhabdoid tumor, first described in the kidney of young infants, is a rare and highly aggressive neoplasm of controversial histogenesis that has been reported at many other sites, including the gastrointestinal tract. However, malignant rhabdoid tumor of the small intestine is very rare, with only seven cases published to date. We report a 70‐year‐old man who presented with abdominal pain and weight loss, and showed a perforated jejunal mass with disseminated metastases by imaging. The patient underwent partial jejunectomy and biopsy of a liver metastasis. Microscopically, the tumor was characterized by neoplastic cells with vesicular nuclei, large nucleoli and abundant eccentric cytoplasm with hyaline globular intracytoplasmic inclusions. Immunohistochemically, the neoplasm coexpressed vimentin and epithelial antigens (AE1/AE3, Cam 5.2, CK34βE12, CK19 and EMA), most of them showing a peculiar immunostaining pattern in relation to the globular inclusions. Ultrastructurally, the inclusions corresponded to paranuclear whorls of intermediate filaments. The patient received postoperative chemotherapy but died 9 months after surgery. In summary, we report the exceptional case of an undifferentiated carcinoma of the jejunum with rhabdoid phenotype. As with tumors at other sites, recognition of rhabdoid morphology in small intestine neoplasms is of significance because the prognosis is extremely poor.  相似文献   
140.
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