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91.
92.
Permanent impairment of embryo development by hydrosalpinges   总被引:6,自引:9,他引:6  
Recent reports suggest a deleterious effect of hydrosalpinges on pregnancy outcome for in-vitro fertilization (IVF) and improvement following surgical treatment. We compared the effect of hydrosalpinx on pregnancy outcome in 286 patients having 348 IVF cycles and followed the development of untransferred embryos for 7 days to determine if hydrosalpinges affect oocyte quality or embryo development. The delivery rate per retrieval was significantly lower for patients with hydrosalpinx, but was restored by surgical treatment to that of patients without hydrosalpinx. However, the implantation rate per embryo transferred and normal blastulation of untransferred embryos, which were significantly decreased in patients with hydrosalpinx, and growth arrest and degeneration of untransferred embryos, which were significantly increased compared to patients without hydrosalpinx, were not restored by surgical treatment of hydrosalpinges. We conclude that surgical treatment of hydrosalpinges decreases early pregnancy loss and improves pregnancy outcome, possibly by diminishing reversible deleterious effects exerted on the endometrium. As we have seen in our laboratory, hydrosalpinges may have a permanent negative influence on ovarian function, follicular development and oocyte quality since implantation of transferred embryos and normal blastulation of untransferred embryos remain low, and in-vitro growth arrest and degeneration remain high despite surgical treatment of hydrosalpinges.   相似文献   
93.
Proteinuria is associated with macrophage-dependent interstitial fibrosis (IF). Osteopontin (OPN), a macrophage chemoattractant, may be involved in the transition of proteinuria to IF but protective properties have also been reported. To elucidate whether OPN may be involved in the proteinuria-induced cascade of tubulointerstitial damage, renal expression of OPN was studied during the development of proteinuria-induced renal damage and during anti-proteinuric intervention with ACE inhibition (ACEi). First, the temporal relationships between proteinuria, interstitial OPN induction, and IF in adriamycin nephrosis (AN), a model of chronic proteinuria-induced renal damage, were studied. Second, the effect of anti-proteinuric treatment on OPN expression was investigated. The time course of OPN induction and markers of renal damage was studied in rats with unilateral AN at 6-week intervals until week 30. In a second study, a renal biopsy was taken 6 weeks after induction of bilateral AN; subsequently, rats were treated with ACEi until termination (week 12). In unilateral AN, proteinuria developed gradually and stabilized at week 10. In proteinuric kidneys, OPN expression was induced from week 12 onwards. Simultaneously, a progressive increase in interstitial macrophages, alpha-smooth muscle actin (alpha-SMA), collagen type III, and focal glomerulosclerosis (FGS) was observed. In bilateral AN, ACEi reduced proteinuria and OPN protein and stabilized fibrosis. In untreated animals, OPN mRNA increased, with stable OPN protein and fibrosis and increased FGS. Thus, in AN, development of proteinuria is followed by up-regulation of OPN along with markers of renal damage. The up-regulation of OPN is reversible by anti-proteinuric treatment without a corresponding reduction in fibrosis. Whereas these data are consistent with a role for OPN in the cascade of transition from proteinuria to fibrosis, intervention with ACEi showed that reduction of OPN does not attenuate established fibrosis.  相似文献   
94.
The effect of transforming growth factor- (TGF-) was analyzed on the synthesis of fibronectin, collagen type IV, and urokinase plasminogen activator in human glomerular epithelial cells in culture. An increase in the abundance of specific mRNA was found for collagen type IV and fibronectin. Fibronectin protein synthesis was also increased in TGF- treated cells; most of the de novo synthesized fibronectin was found as an unsoluble protein associated with extracellular matrix. In the same cells the amount of plasminogen activator mRNA was found leading also to a decreased surface expression of urokinase plasminogen activator. The data support the concept that by upregulating matrix protein synthesis and downregulating the plasminogen activator system, TGF- favors the development of sclerosis.Abbreviations FN Fibronectin - GEC Glomerular epithelial cells - TGF- Transforming growth factor - uPA Urokinase-type plasminogen activator  相似文献   
95.
To evaluate the effects of Medicare's prospective payment system and Medicaid's preadmission regulations on long-term care, we constructed clinical profiles in 1982 and 1986 of about 500 randomly selected patients from each of three types of facilities: nursing homes with relatively high proportions of Medicare patients (high-Medicare nursing homes; n = 23), traditional nursing homes (n = 19), and home health agencies (n = 18). Data were obtained directly from the care givers on the medical problems, problems requiring skilled nursing, and functional problems of these representative patients from 12 states. For Medicare patients in high-Medicare nursing homes, the prevalence of medical problems and problems requiring skilled nursing increased substantially, whereas the prevalence of functional problems remained relatively unchanged. For example, from 1982 to 1986 there was a marked increase in the frequency of tube feedings (21 to 29 percent), oxygen use (6 to 14 percent), urinary tract infection (7 to 13 percent), and diastolic hypertension (1 to 10 percent), but not difficulty in eating (48 to 51 percent) or speaking (28 to 29 percent). In contrast, in traditional nursing homes there was an increase in the prevalence of functional disability, but virtually no change in that of problems requiring medical and skilled nursing care. In home health care the functional care needs of Medicare patients increased significantly, and there was a slight increase in the prevalence of problems requiring medical and skilled nursing care. We conclude that from 1982 to 1986 the needs of patients in long-term care increased substantially. This trend appears to result from Medicare's prospective payment system, which encourages earlier hospital discharge to long-term care settings, and from Medicaid's policy of de-institutionalization. Meeting this greater need for care will be costly. We require a better system of reimbursing for long-term care and ensuring its quality.  相似文献   
96.
Psoriasis is a multifactorial skin disease characterised by epidermal abnormalities and infiltration by lymphocytes and polymorphonuclear leukocytes (PMN). Skin-derived antileukoproteinase (SKALP), also known as elafin, is a potent inhibitor of human leukocyte elastase and proteinase 3, two PMN-derived proteinases implicated in tissue destruction and leukocyte migration. We have shown that, at least at the protein level, SKALP is significantly decreased in lesional skin of patients with pustular psoriasis compared with plaque-type psoriasis. This finding raised the possibility that SKALP could be one of the candidate genes for pustular forms of psoriasis. We therefore performed single strand conformation polymorphism (SSCP) analysis on the SKALP gene to screen for mutations/polymorphisms in the exons of 30 patients with plaque-type psoriasis, 15 patients with pustular psoriasis and 48 healthy controls. In exon 1 a polymorphism was detected at position + 43 relative to the translation start site, resulting in a substitution of threonine for alanine in the signal peptide. In the promoter region a dinucleotide repeat polymorphism was identified. Both polymorphisms were not associated with pustular psoriasis, or psoriasis in general. Our data indicate that the decrease in SKALP activity in pustular psoriasis is not caused by mutations in the coding region of the gene, and that there is no allelic association between pustular psoriasis and SKALP gene polymorphisms.  相似文献   
97.
Cystic fibrosis: Synthesis of ciliary inhibitor by amniotic cells   总被引:1,自引:0,他引:1  
The presence of a ciliary inhibitor in media of cultured amniotic cells obtained from a fetus heterozygous for cystic fibrosis has been observed by the oyster gill cilia assay. The chromatographic fraction containing the inhibitor corresponded to eluted fractions chromatographed from cystic fibrosis fibroblast media and serum. An analogous chromatographic fraction from media of cultured amniotic cells from two proportedly normal fetuses did not inhibit cilia. The chromatographic fraction from media of cultured amniotic cells of a fetus at high risk for cystic fibrosis did not inhibit ciliary activity. Serum was collected from this baby seven weeks after birth and also did not inhibit ciliary action, indicating a homozygous normal genotype. These observations may lead to the development of an antenatal test for cystic fibrosis.  相似文献   
98.
99.
Summary Adult black blowflies Phormia regina were trapped from April through October in Urbana, Illinois for the years 1963 and 1964. Samples of flies from each catch were examined for the presence of the microsporidian parasite Octosporea muscaedomesticae. In 1963, the monthly parasite incidence rate steadily increased with the progression of the seasons while the fly population declined over the same period. In 1964, the monthly parasite incidence rate followed no decernable pattern; this was probably attributable to the fact that the host remained comparatively scarce for the entire period following heavy spring rains. The observed monthly parasite incidence rates ranged from zero to 13% over the two-year period. The annual parasite incidence rate was 4% in 1963 and 4.5% in 1964. No significant differences were found in the parasite incidence rates of females versus males. The observed parasite incidence rates, while indicative of general trends, probably are lower than the actual rates in nature. Reasons for this are discussed. Finally it is suggested that O. muscaedomesticae may at times act as a suppressor of P. regina populations in the field.
Zusammenfassung Erwachsene Fliegen der Art Phormia regina wurden vom April bis Oktober in Urbana, Illinois, in den Jahren 1963 und 1964 gefangen. Einige Fliegen aus jedem Fang wurden auf Microsporidien der Art Octosporea muscaedomesticae untersucht. Im Jahre 1963 erhöhte sich die monatliche Infektionsrate ständig mit dem Fortschreiten des Jahres, während sich die Fliegenpopulation in derselben Periode verminderte. Im Jahre 1964 war eine solche Beziehung nicht erkennbar; dieser Umstand wird darauf zurückgeführt, daß der Wirt während der ganzen folgenden Periode der schweren Frühlingsregenfälle relativ spärlich auftrat. Die beobachtete monatliche Parasitenhäufigkeit wechselte während der 2-Jahresperiode zwischen 0 und 13%. Die jährliche Parasitenhäufigkeit lag 1963 bei 4% und im Jahre 1964 bei 4,5%. Es war keine significante Differenz in der Parasitenhäufigkeit zwischen weiblichen und männlichen Tieren festzustellen. Die beobachtete Parasitenhäufigkeit war, wenn man den generellen Trend betrachtet, wahrscheinlich eher geringer als die aktuelle Rate in der freien Natur. Die Gründe für diese Umstände werden diskutiert. Schließlich wird angenommen, daß sich O. muscaedomesticae als ein begrenzender Faktor (supressor) für P. regina Population in der freien Natur anzusehen ist.


This study was supported in part by Research Grant AI-05068 from the National Institute of Allergy and Infectious Diseases of the National Institutes of Health, U.S. Public Health Service.  相似文献   
100.
These practice parameters are an update of the previously-published recommendations regarding the indications for polysomnography and related procedures in the diagnosis of sleep disorders. Diagnostic categories include the following: sleep related breathing disorders, other respiratory disorders, narcolepsy, parasomnias, sleep related seizure disorders, restless legs syndrome, periodic limb movement sleep disorder, depression with insomnia, and circadian rhythm sleep disorders. Polysomnography is routinely indicated for the diagnosis of sleep related breathing disorders; for continuous positive airway pressure (CPAP) titration in patients with sleep related breathing disorders; for the assessment of treatment results in some cases; with a multiple sleep latency test in the evaluation of suspected narcolepsy; in evaluating sleep related behaviors that are violent or otherwise potentially injurious to the patient or others; and in certain atypical or unusual parasomnias. Polysomnography may be indicated in patients with neuromuscular disorders and sleep related symptoms; to assist in the diagnosis of paroxysmal arousals or other sleep disruptions thought to be seizure related; in a presumed parasomnia or sleep related seizure disorder that does not respond to conventional therapy; or when there is a strong clinical suspicion of periodic limb movement sleep disorder. Polysomnography is not routinely indicated to diagnose chronic lung disease; in cases of typical, uncomplicated, and noninjurious parasomnias when the diagnosis is clearly delineated; for patients with seizures who have no specific complaints consistent with a sleep disorder; to diagnose or treat restless legs syndrome; for the diagnosis of circadian rhythm sleep disorders; or to establish a diagnosis of depression.  相似文献   
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