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971.
The skeletal manifestations of malignant carcinoid seem not to have been reported in the orthopedic literature. Bronchial and hindgut carcinoid tumors are less numerous than midgut tumors but metastasize to bone much more frequently. Carcinoid skeletal deposits are usually osteoblastic and most commonly affect the axial skeleton. The radiologic appearance is frequently indistinguishable from prostatic skeletal metastases or chronic sclerosing osteomyelitis. Two cases of skeletal metastases from midgut carcinoid are reported to demonstrate that metastases from carcinoid should be considered in the differential diagnosis of either bone malignancy or chronic sclerosing osteomyelitis.  相似文献   
972.
The influence of the pore size of Nucleopore diffusion-chamber filters on the rate of proliferation and differentiation of periosteal cells in muscle was studied in 44 growing rabbits. Periosteal grafts were placed in chambers (16-19 in each experimental group) sealed with filters with a pore size of 0.4, 0.6, 0.8, 1.0, or 2.0 micron. Each chamber was implanted into the paraspinal muscle of the rabbit, where it remained for 16 weeks. The osteochondrogenic activity of the graft grew linearly when the pore size increased from 0.4 to 1.0 micron. In the chambers with a pore size of 2.0 micron, both bone and cartilage were found in only one chamber. Bone and cartilage were not found outside any of the chambers. The present results showed that the pore size of the filters significantly affected the ability of the periosteal graft to form bone and cartilage.  相似文献   
973.
The effects of bulk versus particulate polymethylmethacrylate on bone   总被引:3,自引:0,他引:3  
Twenty-one mature New Zealand white female rabbits were allocated into three groups of seven rabbits. Group I received a bolus of doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group II received a preformed, cooled, bulk PMMA pellet. Group III had particulate PMMA powder implanted. The operated, but nonimplanted, left tibiae served as controls. Animals were killed after four months. Histologically, both Group I and Group II demonstrated a thin, fibrous tissue membrane at the implant interface. Particulate PMMA (Group III) stimulated a much thicker, florid, foreign body reaction composed of histiocytes and giant cells. The foreign body response to particulate acrylic cement was similar to that seen in failed cemented joint replacement arthroplasty in humans.  相似文献   
974.
Computed tomography (CT) is currently the imaging modality of choice for assessing the morphology of the adrenal glands in adult patients. Much useful information can be gained using CT in disease processes which primarily involve one or both of the adrenal glands, such as adenomas, as well as in entities which secondarily affect the adrenals, such as pituitary or metastatic disease. The size and configuration of the glands can be readily determined, and masses may be detected. We discuss CT of normal and abnormal adrenal glands with sonographic (US) and pathological correlation, when available. Entities which may mimic adrenal abnormalities are emphasized. Relative advantages of US over CT in the pediatric patient are discussed.  相似文献   
975.
976.
J Arton 《Nursing times》1988,84(14):96-98
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977.
978.
Summary Five monoclonal antibodies against the excretory/secretory (E/S) antigen of Toxocara canis were obtained and characterized. Immunoprecipitating activity was demonstrated in an in-vitro micropre-cipitating assay using live T. canis larvae. Their capacity to kill larvae was also shown in an in-vitro assay. Two zones of reactivity were observed in 7.5 and 12.5% SDS-PAGE (177-77 kD, 43-15 kD) of immunoprecipitates of human and mouse positive polyclonal anlisera. The murine monoclonal antibodies showed a common pattern of reactivity with the proteins in the 177-77 kD range.  相似文献   
979.
Among the enzymes capable of degrading thyrotropin-releasing hormone (TRH) in vitro, two pyroglutamate aminopeptidases (PGA) are specific for TRH: thyroliberinase, a seric enzyme and PGAII, a membrane-bound peptidase. The effect of thyroid hormone status on the activity of these enzymes was evaluated in serum and various tissues. Only in adenohypophysis, triiodothyronine treatment increased PGAII to 376% of control; hypothyroidism produced the reverse effect (decrease to 23% of control). As previously reported, similar changes were observed for thyroliberinase. TRH degradation at the adenohypophysis level may participate in the negative feedback control of thyroid hormones.  相似文献   
980.
Zusammenfassung  Ein PCR-Nachweis für gentechnisch ver?nderten Mais ?Event 176? der Fa. Ciba-Geigy wurde etabliert. Der Mais enth?lt Gene, die Selbstschutz gegen den Maiszünsler (Delta-Endotoxin-Gen ausBacillus thuringiensis) und Toleranz gegen das Herbizid Basta (Phosphinothricin-Resistenz-Gen ausStreptomyces hygroscopicus) vermitteln. Zudem enth?lt der Mais ein Ampicillin-Resistenz-Gen. Für die Amplifikation von Bereichen aus allen drei Genen wurden PCR-Primer entworfen. Mit Hilfe dieser Primer und mit ?Event 176?-Mais-DNA als Template konnten die entsprechenden Genbereiche in der PCR amplifiziert werden. Die PCR-Produkte wurden sequenziert, um ihre Identit?t zu best?tigen. Mit Hilfe der Delta-Endotoxin-PCR wurden, auch in Gegenwart von 104fachem überschu? nicht gentechnisch ver?nderter Mais-DNA, fünf haploide Genome der ?Event 176?-DNA nachgewiesen.
Identification of genetically modified maize by PCR
Summary  A PCR-test for the genetically modified maize ?Event 176? of Ciba-Geigy was established. The maize contains genes conferring resistance to the European corn borer (delta-endotoxin gene fromBacillus thuringiensis) and tolerance to the herbicide Basta (phosphinothricin resistance gene fromStreptomyces hygroscopicus). The maize contains also an ampicillin resistance gene. Primers were designed and using ?Event 176?-maize-DNA as template internal regions of the three genes were amplified with PCR. The PCR products were sequenced to confirm their identity. Using the deltaendotoxin primers in PCR down to 5 haploid genomes of ?Event 176?-DNA could be detected, even in the presence of a 104fold excess of DNA from non-modified maize.
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