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991.
Pelvic ultrasound and human chorionic gonadotropin assays are currently the standard methodology to detect tubal pregnancy. We report a case of infertility investigated by hysterosalpingography in which a clinically unsuspected chronic tubal pregnancy was identified with the predisposing factor of bilateral salpingitis isthmica nodosa. The radiographic findings of this very rare cause of tubal filling defect are shown. RID="ID="<e5>Correspondence to:</e5> N. S. Curry Received: 8 July 1997/Accepted: 20 August 1997  相似文献   
992.
Phospholipases A2 were purified from the venoms of Asian monotypic crotalinae snakes including Callosellasma, Hypnale, Deinagkistrodon, and Tropidolaemus by a combination of gel filtration and reversed-phase chromatographic methods. One to four isoforms of the enzyme were found in each of the venoms. The venom enzymes were subjected to N-terminal sequencing up to the 30th amino acids, and their molecular weights were analyzed by electrospray-ionization mass spectrometry. Homologous antiplatelet phospholipase with a conserved Glu 6 residue was found in each of the venoms. Basic phospholipases with Trp 6 (W6) but without detectable enzyme activities were also isolated from the venom of C. rhodostoma, H. hypnale, and T. wagleri. These W6 enzymes showed strong heparin-binding affinity and capable of inducing edema in rat paws. The fact that the venoms of Callosellasma and Hypnale contain similar types of phospholipases is in accord with recent reports that these two taxa formed a clade. Deinagkistrodon venom does not contain phospholipase variants other than the Glu-6 subtype as Trimeresurus, Agkistrodon, and Protobothrops venoms do. Interestingly, the Glu-6 enzyme from T. wagleri venom has a molecular weight of 15,319 Daltons, higher than those of most other venom phospholipases. Our results show that new types of the enzyme are more likely to be found in the venom of monotypic species; the amino acid sequence data or the subtypes of venom-phospholipases are potentially useful as markers or a character system for studying higher-order systematics of venomous snakes.  相似文献   
993.
Three new isoprenylbenzenes, tournefolins A (1), B (2), and C (3), and two new 2-ethoxy-4,5-dihydroxybenzoyl compounds, 4 and 5, together with the known compounds, salicylic acid and allantoin, were isolated from the stems of Tournefortia sarmentosa. The structures of new compounds were elucidated as 2-(4beta-methyltetrahydrofuran-2alpha-yl)-5-(4beta-methyltetrahydrofu ran-2beta-yl)-1,4-dihydroxybenzene (1), methyl 5-(5-hydroxy-2-methoxyphenyl)-3-furoate (2), methyl 5-(2, 5-dihydroxyphenyl)-3-furoate (3), 2-ethoxy-4,5-dihydroxybenzaldehyde (4), and 2-ethoxy-4,5-dihydroxybenzoic acid (5), on the basis of spectral and chemical methods. The relative configuration of 1 was determined by single-crystal X-ray crystallography.  相似文献   
994.
A 77-year-old man presented with painful swelling of his Port-A-Cath insertion site soon after flushing with normal saline. No discomfort or abnormality was found during the saline flush. A chest roentgenogram showed that the disconnected catheter had separated from the disc and was absent from its original location. The disconnected catheter was found embolized, by chest roentgenogram and CT scan, to the right atrium and hepatic vein. The patient was treated successfully with an X-ray guided extraction of the catheter. The possibility of catheter disconnection with embolization should be considered and a chest roentgenogram performed immediately in cases of rapid swelling of subcutaneous tissue around the port chamber after fluid infusion.  相似文献   
995.
Thirty-three women were examined on three or more occasions, each at 2-month intervals. The overall recovery rate of cytomegalovirus (CMV) was 28% (60215). CMV was recovered from 53% of the cases where the local antibody was 1 : 64 or greater but the greatest difference occurred below titers of 1 : 32. Below that level virus was recovered in less than 5%, compared to a prevalence of 35% for cases with a titer of 1 : 32 (P < 0.001). Twenty-eight cases in whom CMV was sought underwent colposcopic examination and had cytologic smears examined by the papanicolaou method. The external uterine cervix with columnar cells only yield a CMV prevalence of 317 (18%). However, if colposcopy showed either atypical transformation or metaplasia the prevalence was 411 (36%). Similarly, it is provocative that the prevalence of CMV appears to increase with abnormal cytologic findings to 33% recovery in severe dysplasia or carcinoma in situ.  相似文献   
996.
Latent membrane protein 1 (LMP-1) is the only Epstein-Barr virus (EBV)-encoded oncogenic protein that has been detected in nasopharyngeal carcinoma (NPC), a cancer that is closely associated with EBV. Previous in-vitro studies have demonstrated that LMP-1 can upregulate epidermal growth factor receptor (EGFR) in epithelial cells. It was not established whether this cellular effect exists in NPC. To assess the association between LMP-1 and EGFR in NPC tissues, 60 NPC specimens were examined by immunohistochemistry using anti-LMP-1 antibody (CS 1–4) and anti-EGFR antibodies (EGFR 1, EGFR 1005). The results revealed that 41 (68.3%) specimens were immunopositive for LMP-1 and 44 (73.3%) specimens over-expressed EGFR. Morphologically, the expressions of LMP-1 and EGFR were homogeneously distributed in the tumor nests. In addition, the correlation between LMP-1 and EGFR was statistically significant (P<0.001, χ2 test, d.f.=1). To elucidate further the correlation between LMP-1 and EGFR in vivo and in situ , an indirect dual immunofluorescence assay was conducted, using secondary antibodies conjugated with fluorescein isothiocyanate (FITC) or indocarbocyanine (Cy3). The results disclosed an intimate co-expression of LMP-1 and EGFR. In summary, the data indicate that over-expression of EGFR is a common phenomenon in NPC, and that EGFR is co-expressed with LMP-1 in NPC. Thus, EBV may play a role in the tumorigenesis of NPC through the effects of LMP-1 and EGFR.  相似文献   
997.
998.
999.
(1) Background: The association of sugar-sweetened beverages (SSBs) with cardiovascular disease (CVD) mortality in younger adults (age 20–39) is rarely mentioned in the literature. Younger adults are less vulnerable to CVDs, but they tend to consume more SSBs. This prospective study aimed to assess the association between CVD mortality and SSBs in younger adults between 1994 and 2017. (2) Methods: The cohort enrolled 288,747 participants consisting of 139,413 men and 148,355 women, with a mean age 30.6 ± 4.8 years, from a health surveillance program. SSBs referred to any drink with real sugar added, such as fructose corn syrup or sucrose. One serving of SSB contains about 150 Kcal of sugar in 12 oz of drink. Cox models were used to estimate the mortality risk. (3) Results: There were 391 deaths from CVDs in the younger adults, and the positive association with CVD mortality started when SSB intake was ≥2 servings/day (HR: 1.59, 95% CI: 1.16–2.17). With mortalities from diabetes and kidney disease added to CVDs, the so-called expanded CVD mortality risk was 1.49 (95% CI: 1.11–2.01). By excluding CVD risk factors (hypertension, diabetes, and smoking), the CVD mortality risk increased to 2.48 (95% CI: 1.33–4.62). The dose–response relationship persisted (p < 0.05 for trend) in every model above. (4) Conclusions: Higher intake of SSBs (≥2 servings/day) was associated with increased CVD mortality in younger adults. The younger adults (age 20–39) with SSB intake ≥2 servings/day had a 50% increase in CVD mortality in our study, and the mortality risk increased up to 2.5 times for those without CVD risk factors. The dose–response relationship between the quantity of SSB intake and the mortality risk of CVD in younger adults discourages SSB intake for the prevention of CVD mortality.  相似文献   
1000.
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