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111.
Techniques were developed to enhance the frequency of antigen-specific hybridomas by enriching for antibody precursor or -producing lymphocytes prior to cell fusion. Spleen cells of immunized animals were either (a) cultured in vitro for 3–4 days in the presence of the immunizing antigen or (b) adoptively transferred into X-irradiated syngeneic recipients followed immediately by an in vivo antigen boost 4 days prior to use in cell fusion. There was a 10-fold increase in the percentage of wells which develop antigen-specific, antibody-secreting hybridomas following these treatments. These techniques allow an increased yield of hybridomas with a greatly decreased technical effort.  相似文献   
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There have been some claims that green tea reduces weight and lowers blood glucose in diabetes. Intraperitoneal injections of green tea catechins in diabetic rats have shown beneficial effects. To determine if oral administration of green tea would prevent development of diabetes, young Zucker diabetic rats were dosed with green tea extract containing 50-125 mg/kg of Epigallocatechin gallate (EGCG) starting at 7 weeks of age, before the appearance of excessive weight gain and glucose elevation. While there was a trend toward lower weight gain and average daily glucose, there was no statistically significant difference.  相似文献   
114.
Maffucci syndrome is a rare, congenital disease, which is associated with the appearance of multiple enchondromas (possibility of malignant transformation in 20 to 100%), soft tissue hemangiomas and other mesenchymatous injuries. Case 1 is a 33-year-old female who presented with multiple nodules predominantly in upper extremities. Upon examination, there was deformity in articulation and nodules on the hands, which were soft and moveable. There were bony shavings in the second and fourth fingers of the left hand (enchondromas and atypical cells associated with hemangioma esclerosante). Maffucci syndrome was diagnosed. Later, excision of subcutaneous nodules in superior extremities was performed along with excision of nodules in both hands and hypochondrium (enchondroma injuries of left hand and hypochondrium, hemangioma in right hand). There was dysarticulation of the second finger at the metacarpal level of the phalanges of the left hand (chondrosarcoma). The patient is being followed up currently. Case 2 is a 26-year-old female. The patient had a history of subcutaneous abdominal tumor, exostosis, nodules and nodule in right breast. Upon examination, a tumor was found in the right breast, exostosis of right tibia, injury to the right wrist and left thyroid nodule. A simple mastectomy and axillary dissection was performed (fibroadenoma to intracanalicular and 14 negative lymph nodes). Later, left thyroidectomy and lumpectomy in right wrist were performed (hyperplasia to nodular thyroid and hemangioma cavernous). There was injury in the carpus of the right hand and elbow (hemangioma cavernous and synovial tissue with fibrosis and enchondroma). A diagnosis was made of Marffucci syndrome associated with mesenchymatous tumors. The patient was in poor general health and did not survive this hospitalization.  相似文献   
115.
Forty years ago, Marshall Urist described a partially purified extract of demineralized bone matrix which induced the formation of ectopic bone. This substance, bone morphogenetic protein/non-collagenous protein (BMP/NCP), was never purified to homogeneity but other investigators used similar starting materials to clone a number of recombinant BMPs. Urist recognized that his material probably contained the BMPs which had been cloned by others but always contended that it contained another, more potent, bone inducing material which differed significantly in its physical and chemical properties from the known BMPs. We have used Urist's protocol to isolate a protein that has the chemical and physical properties of Urist's "BMP". It is an 18.5 kD fragment of the bone matrix protein, SPP-24. This fragment contains the cystatin-like domain of SPP-24. We have located a 19 amino acid region which is similar to the TGF-beta/BMP-binding region of fetuin, a member of the cystatin family of protease inhibitors. A cyclic peptide, which we call BMP binding peptide (BBP) was generated using this sequence. The peptide avidly bound rhBMP-2 with a KD of 3 x 10(-5) M. When implanted alone in mouse muscle, the peptide frequently induced dystrophic calcification. When implanted with rhBMP-2, the peptide enhanced the osteogenic activity of the recombinant molecule. We hypothesize that Urist's "BMP" was a fragment of SPP-24 which influenced bone induction by binding to bone morphogenetic proteins. BBP may be clinically useful because of its effects on other bone-inducing substances.  相似文献   
116.
BACKGROUND: McDonald's has sold >100 billion beef-based hamburgers worldwide with a potentially considerable health impact. This paper explores whether there would be any advantages if the next 100 billion burgers were instead plant-based burgers. METHODS: Nutrient composition of the beef hamburger patty and the McVeggie burger patty were obtained from the McDonald's website; sales data were obtained from the McDonald's customer service. RESULTS: Consuming 100 billion McDonald's beef burgers versus the same company's McVeggie burgers would provide, approximately, on average, an additional 550 million pounds of saturated fat and 1.2 billion total pounds of fat, as well as 1 billion fewer pounds of fiber, 660 million fewer pounds of protein, and no difference in calories. CONCLUSIONS: These data suggest that the McDonald's new McVeggie burger represents a less harmful fast-food choice than the beef burger.  相似文献   
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Several studies have confirmed a decrease in the quality and quantity of milk of mothers with diabetes during lactation. However, it remains unclear how maternal diabetes affects the offspring specifically during lactation. The aim of this study was to evaluate body and mandibular growth and tooth eruption in pups suckling from diabetic dams. The study was performed on 13 Wistar rat pups that were born to dams that were subjected to experimental diabetes on the day of parturition. Body weight and body size were recorded regularly throughout the study. The experimental pups and a group of eight age-matched pups suckling from nondiabetic dams were killed at weaning. Both hemimandibles were excised and fixed. Right hemimandibles were radiographed to assess mandibular growth and tooth eruption. The left hemimandibles were processed to obtain buccolingually oriented sections at the level of the first mesial root of the first lower molar. Histologic and histomorphometric studies were performed. Results showed that body weight and body size were significantly lower in experimental animals at weaning compared with their age-matched controls. Smaller mandible size and reduced tooth eruption in experimental animals compared with controls were observed. The length, width, and bone volume of the developing alveolus were reduced in experimental animals compared with controls. The results obtained in this study allow the conclusion that suckling from diabetic dams results in reduced body, mandible size, and tooth eruption of the pups at weaning.  相似文献   
119.
Children with gestational cocaine exposure may be at risk of difficulties in attentional functioning and impulse control. We administered the Gordon Diagnostic System and subtests of the Halstead-Reitan Battery to inner-city children with (COC) and without (CON) gestational cocaine exposure at age 10 years. Subtle differences were found between groups, with differences in Gordon Delay (Efficiency Ratio) and Gordon Distractibility (Total Commissions). With these two exceptions, children had similar performance, with both groups performing poorly. Attentional functioning and impulse control were also assessed in school. Teachers did not distinguish between COC and CON, although both groups presented behavioral problems. We conclude that gestational cocaine exposure may be associated with subtle problems in attention and impulse control, putting exposed children at higher risk of developing significant behavioral problems as cognitive demands increase.  相似文献   
120.
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