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1.
Summary During a follow-up of 11 years of thyroid carcinoma 136 patients were repeatedly examined. 43% papillary, 43% follicular, 11% anaplastic and 2% medullary carcinomas was found. The incidence of these types of carcinoma differed considerably; the frequency peak of papillary carcinomas was reached in 45-year-old humans, that of the follicular carcinomas in people aged 60, that of the anaplastic carcinomas in 70-year-old humans.84% of the patients was female. Classification in pTNM-system: 8% in pT1, 27% in pT2, 12% in pT3 and 49% in pT4. Local and distant metastases were found at a low rate equally in pT1, pT2 and pT3; 26% of patients in pT4 had local metastases and 18% had distant ones in addition. There were 6 patients with metastases of a differentiated adenocarcinoma accumulating no 131-iodine and with no thyroglobulin in serum. 29% of patients had after thyroidectomy an unilateral paresis of the nervus recurrens and 4% a bilateral one. 26% of patients had a permanent hypoparathyroidism after thyroidectomy.Dedicated to Prof. L.E. Feinendegen on the occasion of his 60th birthday  相似文献   
2.
Cells of the purple non-sulphur bacterium Rhodobacter sphaeroides express a high-affinity K+ uptake system when grown in media with low K+ concentrations. Antibodies againts the catalytic KdpB protein or the whole KdpABC complex of Escherichia coli crossreact with a 70.0 kDa R. sphaeroides protein that was expressed only in cells grown in media with low K+ concentrations. In membranes derived from R. sphaeroides cells grown with low K+ concentrations (induced cells), a high ATPase activity could be detected when assayed in Tris-HCl pH 8.0 containing 1 mM MgSO4. This ATPase activity increased upon addition of 1 mM KCl from 166 to 289 mol ATP hydrolysed x min-1 x g protein-1 (1.7-fold stimulation). The K+-stimulated ATPase activity was inhibited approximately 93% by 0.5 mM vanadate but hardly by N,N-dicyclohexylcarbo-diimide (DCCD). These results indicate that the inducible K+-ATPase in R. sphaeroides resembles the Kdp K+-translocating ATPase of Escherichia coli. This Kdp-like transport system is also expressed in R. capsulatus and Rhodospirillum rubrum during growth in media with low K+ concentrations suggesting a wide distribution of this transport system among phototrophic bacteria.Abbreviations electrical potential difference across the cytoplasmic membrane - pH pH difference across the cytoplasmic membrane - BSA bovine serum albumine - PAGE polyacrylamide gel electrophoresis - HEPES 4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid - PMSF phenyl-methyl-sulfonyl fluoride - DCCD N,N-dicyclohexylcarbodiimide - AIB 2--aminoisobutyric acid - TMG methyl--d-thiogalactopyranoside  相似文献   
3.
The Kdp system from Escherichia coli is a derepressible high-affinity K+-uptake ATPase. Its membrane-bound ATPase activity was approximately 50 mumol g-1 min-1. The Kdp-ATPase complex was purified from everted vesicles by solubilization with the nonionic detergent Aminoxid WS 35 followed by DEAE-Sepharose CL-6B chromatography at pH 7.5 and pH 6.4 and gel filtration on Fractogel TSK HW-65. The overall yield of activity was 6.5% and the purity at least 90%. The isolated KdpABC complex had a high affinity for its substrates K+ (Km app. = 10 microM) and Mg2+-ATP (Km = 80 microM) and a narrow substrate specificity. The ATPase activity was inhibited by vanadate (Ki = 1.5 microM), fluorescein isothiocyanate (Ki = 3.5 microM), N,N'-dicyclohexylcarbodiimide (Ki = 60 microM) and N-ethylmaleimide (Ki = 0.1 mM). The purification protocol was likewise applicable to the isolation of a KdpA mutant ATPase which in contrast to the wild-type enzyme exhibited an increased Km value for K+ of 6 mM and a 10-fold lowered sensitivity for vanadate. Starting from the purified Kdp complex the single subunits were obtained by gel filtration on Bio-Gel P-100 in the presence of SDS. Both the native Kdp-ATPase and the SDS-denatured polypeptides were used to raise polyclonal antibodies. The specificity of the antisera was established by immunoblot analysis. In functional inhibition studies the anti-KdpABC and anti-KdpB sera impaired ATPase activity in the membrane-bound as well as in the purified state of the enzyme. In contrast, the anti-KdpC serum did not inhibit enzyme activity.  相似文献   
4.
The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.  相似文献   
5.
During the period of COVID-19, the occurrences of mucormycosis in immunocompromised patients have increased significantly. Mucormycosis (black fungus) is a rare and rapidly progressing fungal infection associated with high mortality and morbidity in India as well as globally. The causative agents for this infection are collectively called mucoromycetes which are the members of the order Mucorales. The diagnosis of the infection needs to be performed as soon as the occurrence of clinical symptoms which differs with types of Mucorales infection. Imaging techniques magnetic resonance imaging or computed tomography scan, culture testing, and microscopy are the approaches for the diagnosis. After the diagnosis of the infection is confirmed, rapid action is needed for the treatment in the form of antifungal therapy or surgery depending upon the severity of the infection. Delaying in treatment declines the chances of survival. In antifungal therapy, there are two approaches first-line therapy (monotherapy) and combination therapy. Amphotericin B ( 1 ) and isavuconazole ( 2 ) are the drugs of choice for first-line therapy in the treatment of mucormycosis. Salvage therapy with posaconazole ( 3 ) and deferasirox ( 4 ) is another approach for patients who are not responsible for any other therapy. Adjunctive therapy is also used in the treatment of mucormycosis along with first-line therapy, which involves hyperbaric oxygen and cytokine therapy. There are some drugs like VT-1161 ( 5 ) and APX001A ( 6 ), Colistin, SCH 42427, and PC1244 that are under clinical trials. Despite all these approaches, none can be 100% successful in giving results. Therefore, new medications with favorable or little side effects are required for the treatment of mucormycosis.  相似文献   
6.
Summary In a previous report (Zenzes et al., 1978 b) it was shown that dissociated ovarian cells of newborn rats in vitro, if exposed to H-Y antigen, reorganize into testicular structures. The current study was designed to see whether this morphological conversion also results in a functional conversion. The LH/hCG receptor was used as a parameter characteristic for the newborn testis, but not for the newborn ovary. In the converted ovary, the LH/hCG receptor becomes detectable a few hours after onset of the culture and remains continuously present afterward. The appearance of this receptor may be due to a hormone-like action of H-Y antigen.  相似文献   
7.
Siebers  H. H.  van der Kraan  A. M.  Donzel  M. 《Hydrobiologia》1982,91(1):697-700

Iron compounds of phosphorus form a large part of the phosphorus bound in sediments. Mössbauer spectroscopy is a technique that enables us to study, directly, chemical forms of iron in solid samples. Mössbauer spectroscopy allowed us to check, directly, the selectivity of the extraction scheme for soil phosphorus proposed by Chang &; Jackson (1957), but only as far as the iron compounds are concerned. It appears that selectivity of the extraction method leaves much to be desired.

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8.
AR Boobis  MB Slade  C Stern  KM Lewis  DS Davies 《Life sciences》1981,29(14):1443-1448
Cytochrome P-448 (mol wt 55,000 Daltons) from rabbit liver was purified to a specific content of 16.6 nmol/mg. Mice were immunised with this preparation, their spleens removed and dissociated lymphocytes hybridised with myeloma cells. Four monoclonal antibodies against cytochrome P-448 were raised and partially characterised. All four antibodies interacted with cytochrome P-448 in intact microsomal fractions and selectively immunoadsorbed cytochrome P-448 from solubilised microsomal preparations. One of the antibodies inhibited benzo[a] pyrene hydroxylase activity in a reconstituted system, one had no effect on activity and two increased activity. The possible applications of such antibodies are discussed.  相似文献   
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