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991.
Immunohistochemical characterization of extracellular matrix in the developing human cornea 总被引:4,自引:0,他引:4
Collagen, fibronectin and laminin are important components of the extracellular matrix of the human cornea. We used the immunofluorescence technique with polyclonal antibodies directed against these proteins and to bullous pemphigoid antigen (BPA), in order to study their distribution in human corneas from 8 weeks of gestation to term and in adult corneas. Immunoreactivity was observed with antibodies to type I collagen in the limbus and the corneal stroma at 8 weeks of gestation. At 11 weeks of gestation it was found in epithelial basement membrane (EBM) and Descemet's membrane (DM) and continued thus throughout fetal and adult life. Type II collagen was not detected in fetal or adult cornea. Type III collagen was detected during 8-20th weeks of gestation in the EBM, DM and stroma. After 27th weeks of gestation, type III collagen could no longer be detected in the central cornea. Type IV collagen was detected in the EBM as early as 8 weeks of gestation and remained positive throughout fetal and adult life. Descemet's membrane was negative for type IV collagen at 8 weeks of gestation and became positive thereafter. Immunostaining for fibronectin in DM was negative at 8 weeks of gestation, followed by patchy staining of corneal stroma and EBM up to the age of 37 weeks of gestation. Staining in the EBM was negative or variable up to 70 years of age, and then became positive again in a 77 year old individual. Staining for LN was positive in the EBM after 8 weeks of gestation. Staining was negative in DM at that age, but became positive after 9 weeks of gestation. Staining for BPA was negative at 8-9 weeks of gestation, then gradually became positive. 相似文献
992.
A new rapid procedure for desiccating frozen resin-cracked retinal tissue for scanning electron microscopy (SEM) which permits air-drying was found to compare favorably with tissues prepared by critical-point drying: Retinal tissue was fixed in 4% phosphate-buffered neutral formaldehyde, dehydrated by means of graded ethanol, embedded in Epon, cracked and washed in propylene oxide. For desiccation, the specimens were immersed in hexamethyldisilazane (HMDS), air-dried and finally sputter-coated. The method is time-saving, gives extended information in SEM, and the number of good specimens is increased. 相似文献
993.
Perbendazole was given orally and subcutaneously to mice infected with Angiostrongylus cantonensis at different stages of infection. The subcutaneous route of administration was more effective than the oral one. On the 5th day after infection, the perbendazole had a higher efficacy than on the 10th day postinfection. This finding shows that perbendazole had complete larvicidal effect at early stages of infection. 相似文献
994.
A retrospective study of 239 patients who were hospitalized for diverticular disease is reported. Two thirds of patients had simple diverticulosis, and the remainder had gastrointestinal bleeding, evidence of microabscess, or more serious complications. The prevalence of bleeding on the left side in this series differs from the prevalence of right-sided bleeding noted in the literature, and this difference is unexplained. Only three patients in this series died (overall mortality, 1.2%); all had other associated life-threatening diseases. 相似文献
995.
Case-adjusted prospective reimbursement systems, such as resource utilization groups (RUGs), may promote nursing home cost containment, but they may do no better than existing systems at encouraging homes to admit the more dependent and thus costlier Medicaid patients, if the homes' reluctance to admit these patients is due to a shortage of nursing home beds. Using 1983 data on Wisconsin nursing homes, this paper presents evidence that suggests that the presence of excess demand, rather than low reimbursement rates, causes nursing homes to exclude the more costly Medicaid patients. Consequently, to benefit fully from RUGs, it is necessary either to eliminate excess demand (by increasing supply or decreasing demand) or to decide which patients have priority for admission and assign reimbursement payments to these patients that significantly favor these patients. Otherwise, access to nursing home care under RUGs is left to chance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
997.
N Nelson O Finnstr?m L Larsson 《Scandinavian journal of clinical and laboratory investigation》1987,47(2):111-117
Thirty-one full-term newborn babies were investigated in order to establish reference values for ionized calcium. Only children fulfilling certain optimality criteria (with best possible maternal and infant conditions and uncomplicated pregnancy and delivery) were included. All infants were breast fed. Capillary blood for analysis of ionized calcium was collected by heel puncture on day 1 (6-36 h post partum, p.p.), day 3 (60-84 h p.p.) and day 5 (108-132 h p.p.). Ionized calcium was measured with a semi-automatic electrode system ICA 1 (Radiometer A/S, Copenhagen, Denmark). The reference ranges (mean +/- 2 SD) for days 1, 3 and 5 were 1.05-1.37, 1.10-1.42 and 1.20-1.48 mmol/l, respectively. The mean ionized calcium concentration on day 1 was significantly lower than on days 3 and 5. Reference values are also given for total calcium, magnesium and phosphate. We emphasize that it is impossible to calculate ionized calcium from total calcium or vice versa. 相似文献
998.
Fifty-five patients with vascular insufficiency resulting in above-knee (AK) and through-knee (TK) amputations were studied to determine factors related to prosthetic candidacy and functional outcome. Chart review showed that the only difference between patients who were fitted with prostheses and those who were not fitted with prostheses was their respective number of medical complications. Twenty-three of 31 patients with prostheses were evaluated 7 to 35 months after receiving the prostheses. Ten (44%) of these patients wore their prostheses all day every day and used wheelchairs minimally or not at all. Over half of the patients evaluated used their wheelchairs most of the time. Two (9%) of the 23 patients had stopped wearing their prostheses. Patients who demonstrated increased walking distances and velocities at follow-up used their prostheses more and their wheelchairs less than did the other patients. Neither gait factors nor hip range of motion at discharge was predictive of continued prosthetic use. Functional outcome and prosthetic use were limited in this group of elderly patients with dysvascular AK and TK amputations. The results of this study may serve as a basis for clinical determination of prosthetic candidacy and functional goals. 相似文献
999.
P M Battey J T Fulenwider R B Smith L G Martin M T Stewart G D Perdue 《Southern medical journal》1987,80(4):479-482
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation. 相似文献
1000.
Nancy L. Snyderman 《The Laryngoscope》1987,97(3):353-356
Trichinosis is a rare cause of a neck mass, but should be considered by the physician when contemplating a differential diagnosis. This disease is still endemic in parts of the world and is directly related to the ingestion of incompletely cooked pork. A case is presented in which a 68-year-old man was diagnosed as having a squamous cell carcinoma of the mandible only to have trichinosis diagnosed on the final pathologic report. The case presentation is followed by a historical review and discussion. 相似文献