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31.
Eighteen individuals with IDDM (type I) and diabetic nephropathy in whom the initial glomerular filtration rate (GFR) was reduced but not below 60 ml/min per 1.73 m2 were observed for an average of 3 yr. The rate of further decline of GFR was found to range between -2 and 21 ml/min/yr. The duration of diabetes until the GFR was first found to be reduced varied between 14 and 33 yr and was not correlated to the ensuing rate of decline in GFR (r = -0.13). In 10 individuals who developed uremia 40 yr or more after onset of IDDM, the development of persistent proteinuria was followed by hypertension and increased serum creatinine 2 yr later and by terminal uremia after an average of 8 yr. This is also the normal time span for individuals who develop terminal uremia after shorter duration of diabetes. We conclude that the course of clinical diabetic nephropathy is not more favorable in individuals with late onset of this complication and that there is no point at which a person with diabetes can be considered to be spared from developing diabetic nephropathy. 相似文献
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The stability of betamethasone-17-valerate in semi-solid bases has been investigated. Emphasis has been placed on the stability problems which could arise upon dilution of proprietary preparations by the use of model systems. Betamethasone-17-valerate has been shown to decompose to betamethasone-21-valerate and betamethasone alcohol. Quantitation of the decomposition was by direct densitometry on thin layer chromatographic plates. The decomposition was found to be an apparent first order process and to depend on the diluent used and its concentration. Attempts were also made to relate the rate of decomposition to the pH of the base used, and to stabilize the products. 相似文献
34.
Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation. 相似文献
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Prognostic factors for the success rate of embryo freezing 总被引:5,自引:6,他引:5
Karlstrom PO; Bergh T; Forsberg AS; Sandkvist U; Wikland M 《Human reproduction (Oxford, England)》1997,12(6):1263-1266
To find some prognostic factors for the outcome of frozen-thawed cycles, we
have retrospectively analysed all frozen pre-embryos that were thawed
during 1993 and 1994 at two in-vitro fertilization (IVF) units in Sweden.
Supernumerary pre-embryos were frozen from 551 oocyte retrievals and these
resulted in 660 frozen-thawed cycles which lead to 623 thawed embryo
transfers. The outcome of these transfers was 137 clinical pregnancies with
a pregnancy rate of 22% per frozen-thawed embryo transfers. Women <40
years of age had a higher birth rate than those > or =40 years, 19 and
5% respectively (P < 0.01). Transfers with two and three pre-embryos
resulted in pregnancy rates of 23 and 27%, respectively, compared with 14%
for transfer of one embryo. A pregnancy resulting from the initial embryo
transfers had a predictive value for results of the subsequent
frozen-thawed cycle. Embryo grade and cleavage stage at the time of
freezing was important for the survival of the frozen-thawed pre-embryos.
The pregnancy rate was not influenced by the cleavage stage, but a tendency
toward a lower pregnancy rate was seen for the embryos with lower grading.
To conclude, cryopreservation seems to be beneficial in women <40 years
of age, who have supernumerary pre-embryos of good quality for freezing and
of which at least two can be transferred.
相似文献
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The plasma levels of homocysteine are elevated in moderate renal insufficiency but do not predict the rate of progression. 总被引:2,自引:0,他引:2
O Samuelsson D M Lee P O Attman C Knight-Gibson J K Mullen R Larsson H Mulec L Weiss P Alaupovic 《Nephron》1999,82(4):306-311
BACKGROUND: Chronic renal failure is characterized by specific alterations of the lipoprotein metabolism. It is also characterized by elevated plasma levels of total homocysteine (tHcy). Hyperhomocysteinemia has been shown to be a risk factor for atherosclerosis in both the general population and in patients with end-stage renal disease. AIM: To analyze whether elevated tHcy levels also may contribute to a higher rate of progression of renal insufficiency in patients with moderately advanced renal failure. METHODS: To investigate whether tHcy concentrations are associated with an accelerated rate of progression of renal insufficiency, we have correlated baseline plasma concentrations of tHcy with the progressive decline of renal function in an observational study of human chronic renal disease. RESULTS: Sixty-three nondiabetic patients (49 men, 14 women) were studied as part of an observational study of patients with moderately advanced renal insufficiency. The average follow-up time of the patient population was 3.0 years, and the mean rate of decline in glomerular filtration rate ((51)Cr- EDTA clearance) was -3.2 +/- (SD) 3.9 ml/min x 1.73 m(2) body surface area. The mean plasma concentration of tHcy at the beginning of the study was 28.3 +/- 12.0 micromol/l. Plasma tHcy concentrations correlated significantly with the glomerular filtration rate (r = -0. 32, p < 0.01). However, there was no association between the initial plasma level of tHcy and the rate of progression as assessed by linear regression analysis (r = 0.02; NS). In contrast, increased levels of apolipoprotein B, low-density lipoprotein cholesterol, and proteinuria were all significantly associated with a more rapid decline in renal function. CONCLUSIONS: Patients with moderately advanced chronic renal insufficiency have elevated plasma levels of homocysteine. The tHcy plasma levels increase in parallel with the degree of reduction in renal function. However, the hyperhomocysteinemia is not prospectively associated with a higher rate of progression of the renal functional impairment. Hence, there is no indication that elevated homocysteine levels play a contributing role for an accelerated glomerulosclerotic process. 相似文献
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