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951.
The fatty acid composition of three freshwater sponges—Ephydatia syriaca, Nudospongilla sp., andCortispongilla barroisi—were studied. Twenty principal fatty acids, and unusually high levels of eicosatetraenoic (5,8,11,14–20:4 up to 10.1% of the total acid mixture), eicosapentaenoic (5,8,11,14,17–20:5 up to 11.6%), and docosahexaenoic acids (4,7,10,13,16,19–22:6 up to 11.8%) were detected. The only demospongic acid found was 5,9,17-hexacosatrienoic acid (1.8–3.7%).  相似文献   
952.
We examined the influence of renal ischemia in rats with diabetes mellitus (DM). Male Wistar rats were rendered diabetic by streptozotocin treatment. Two weeks later, 30 minutes of complete ischemia was induced in the left kidney of DM and non-DM animals. Both groups were evaluated functionally and morphologically four or eight weeks post-ischemia. In non-DM animals renal function and morphology showed almost complete recovery. In the DM animals, however, this comparatively short period of ischemia caused a substantial loss of renal function. Four weeks post-ischemia inulin clearance in the DM kidneys rendered ischemic was only 20% of that in the corresponding non-DM kidneys, and after eight weeks the DM kidneys were completely anuric. Extensive inflammation and tubulointerstitial fibrosis were evident in DM kidneys four weeks after ischemia and seemed to increase over time. After eight weeks, tubular atrophy was found in the ischemic DM kidneys, resulting in a substantial loss of kidney mass. We conclude that in diabetic rats renal ischemia causes rapidly progressive kidney damage that in several respects resembles diabetic nephropathy in humans. Since advanced renal lesions similar to those seen in human diabetic nephropathy never develop in the rat solely as a result of DM, the present study may provide an experimental model for further studies on renal failure in diabetes mellitus.  相似文献   
953.
INTRODUCTION: In an attempt to establish the value of MRI, VEP, SEP, and biotesiometry in monitoring disease evolution we undertook a one year follow up study of 70 untreated patients with acute optic neuritis (ON). MATERIAL & METHODS: ON was monosymptomatic in 48 patients (bilateral in 10) and part of clinically definite multiple sclerosis (CDMS) in 22 patients, examined as mentioned below. RESULTS: Results are given at onset and at follow up (in brackets). In monosymptomatic ON, brain MRI was abnormal in 53% (53%), VEP in the eye with acute ON in 79% (71%), VEP in the clinically unaffected eye in 34% (47%), SEP in 25% (23%), and biotesiometry in 29% (17%). In CDMS, brain MRI was abnormal in 95% (95%), VEP in the eye with acute ON in 86% (77%), VEP in the clinically unaffected eye in 50% (64%), SEP in 55% (50%), and biotesiometry in 63% (53%). Only minor changes in test scores were observed after one year except for significant improvement of VEP in eyes with acute ON. Eight of 32 patients, characterized by at least one abnormal paraclinical test at onset of monosymptomatic ON, had developed CDMS versus none of 16 patients with normal paraclinical results (p = 0.03; Fisher). CONCLUSION: Patients with monosymptomatic ON with paraclinical signs of multifocal involvement at onset had an increased risk of developing CDMS. No single test predicted the evolution of CDMS, perhaps due to the relatively short follow up time.  相似文献   
954.
Revascularization of acutely ischemic muscle tissue is followed by edema, decreased oxygen utilization, increased vascular resistance and massive efflux of intracellular compounds indicating loss of cellular integrity, with resultant irreversible damage. In this pig hindlimb study, 8 pigs were submitted to standardized subtotal ischemia of one leg and mannitol was administered i.v. prior to and during 2.5 hours of reperfusion. Compared to 9 controls, the mannitol treated pigs had increased blood flow to the legs, increased oxygen consumption and decreased release of intracellular compounds (CK). This indicates that mannitol attenuates the ischemia/reperfusion syndrome. Muscle energy metabolic parameters showed a similar response to ischemia for both mannitol-treated pigs and controls and no differences in recovery were detected during 2.5 hours of reperfusion between the groups.  相似文献   
955.
Monoclonal antibodies were raised to a synthetic peptide corresponding to amino acids 1-29 of the human gonadotropin-releasing hormone (GnRH) receptor. One of the two antibodies was found to recognise GnRH receptors on human pituitary gonadotrophs as determined by immunohistochemistry and supported by Western blotting. The antibody also bound to T47D human breast carcinoma cell line as determined by flow cytometric analysis.  相似文献   
956.
Strategic energy planning is concerned with investments in energy technologies with long lead times and long life times. Of special interest are uncertainties about future developments that could lead to a major reappraisal of the cost-efficiency of different energy technologies. Decision making in this context is concerned, therefore, with finding a solution to the decision problem which is both low-cost and robust. Here, a method is described for using hedging to improve the robustness of the energy system. The method is applied using a standard energy systems model, MARKAL. It is shown how the model results can be used for a quantitative analysis of the robustness of the energy system. A study of the Swedish energy system is used as an example, where the uncertain factor is whether or not future restrictions on CO2 emissions will be imposed.  相似文献   
957.
958.
The authors show case of lateral cervical cyst and carcinoma of the tonsil in woman 50 years, paying attention to large diagnostic and therapeutic difficulties. After operation of the lateral cervical cyst on the left side, metastasis of tumor followed, which was operated (after negative result of the thin-needle biopsy method) and histopathological examination of the tumor didn't prove atypical cells. In a few month after operation there followed tumorous infiltration in region angle of mandibula and in tonsillar region on the side and performed the thin-needle biopsy method showed planoepithelial carcinoma of the tonsil with transitional cells, which infiltrated the lingua, fundus of the oris and lymphonodes of the neck. Next the patient was sent to further treatment in the Oncological Hospital in Lodz. In connexion with advanced of the carcinoma, the using treatment (radiotherapy Co--60 and chemotherapy) was only the palliative treatment and prolongated life of the patient about 3 years.  相似文献   
959.
960.
We present uniformity data on resonant cavity-enhanced InGaAs-AlGaAs heterojunction phototransistors (HPT's) with an optical design that promotes high uniformity and yield. The HPT's operate in the wavelength region where the GaAs substrate is transparent and the data show the HPT's to be suitable for vertical integration with optical emitters or modulators to form two-dimensional arrays of smart pixels operating in transmission mode. The absorbing region of the HPT consists of an InGaAs multiple-quantum-well structure where the quantum wells (QW's) have been distributed to make the total absorption in the cavity insensitive to growth variations as well as the spatial matching of the standing wave and absorbing QW's. Theoretically, we estimate the absorption to be 39%±1% of the incident optical power, even at wafer nonuniformities of 12.5%. With these nonuniformities, the resonant wavelength moves ±25 nm, making postgrowth tuning of the wavelength necessary. Experimentally, we show postgrowth tuning of the resonance wavelength without loss in uniformity. The arrays have good uniformity as well as very high responsivities. The average responsivity is 160 A/W ±15% from 927-955 nm. The standard deviation of a typical array is 0.5 nm in resonant wavelength and about 5% of the average responsivity. The difference between maximum and minimum values for an array is typically 3 nm in resonant wavelength and ±10% of the average responsivity  相似文献   
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