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1.
Approximately 60% of the outer membrane of chlamydial elementary bodies (EBs) consists of the major outer membrane protein (MOMP) that has structural and metabolic functions. The antigenic properties of MOMPs from mammalian strains of serovars 1 and 2 and an avian strain of Chlamydia psittaci were analyzed. Polyclonal-monospecific antisera (PMAs), one monoclonal antibody (MAb), and polyclonal antisera (PAs) were produced against reduced polyacrylamide gel electrophoresis-separated MOMPs and against infectious EBs. Three PMAs and the MAb, which were induced by reduced polyacrylamide gel electrophoresis-separated MOMPs, reacted strongly in Western blot (immunoblot) assays with MOMPs of serovar 1 and 2 strains as well as with that of the avian strain 6BC, and two of these PMAs reacted weakly (dilution, 1:20) with the MOMP of strain LGV-2. The third PMA and the MAb against the MOMP of the serovar 2 strain did not react with the MOMP of LGV-2. Four PAs were produced against infectious EBs of the serovar 1 strain. One of these PAs reacted with the homologous MOMP and that of the avian strain 6BC but did not recognize MOMPs of other chlamydial strains. Three of the PAs reacted with MOMPs of homologous strains only and failed to recognize MOMPs of avian, serovar 2, and LGV-2 strains. Five PAs induced against infectious EBs of the serovar strain 2 reacted only with the MOMPs of the homologous strains and failed to recognize MOMPs of other strains of chlamydiae. Consequently, MOMPs of C. psittaci strains possess genus-, species-, and serovar-specific epitopes whereby the immune response to serovar-specific epitopes of MOMP predominate when infectious EBs are used for immunization.  相似文献   
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Treatment of small intestinal bacterial overgrowth is frustrated by the low efficacy of antibiotics. Elemental diets have been shown to reduce enteric flora. In this study, we evaluate the ability of an elemental diet to normalize the lactulose breath test (LBT) in IBS subjects with abnormal breath test findings. Consecutive subjects with IBS and abnormal LBT suggesting the presence of bacterial overgrowth underwent a 2-week exclusive elemental diet. The diet consisted of Vivonex Plus (Novartis Nutrition Corp., Minneapolis, MN) in a quantity based on individual caloric requirement. On day 15 (prior to solid food), subjects returned for a follow-up breath test and those with an abnormal LBT were continued on the diet for an additional 7 days. The ability of an elemental diet to normalize the LBT was determined for days 15 and 21. A chart review was then conducted to evaluate any clinical benefit 1 month later. Of the 93 subjects available for analysis, 74 (80%) had a normal LBT on day 15 of the elemental diet. When those who continued to day 21 were included, five additional patients normalized the breath test (85%). On chart review, subjects who successfully normalized their breath test had a 66.4 +/- 36.1% improvement in bowel symptoms, compared to 11.9 +/- 22.0% in those who failed to normalize (P < 0.001). An elemental diet is highly effective in normalizing an abnormal LBT in IBS subjects, with a concomitant improvement in clinical symptoms.  相似文献   
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The majority of investigations on the testis, as the main organ of male reproductive system, have been performed in mammalian species, with few studies on bird species. Thus, the structure of the ostrich testis remains largely unknown. The aim of this study was to investigate the microanatomical characteristics of the testis in five juvenile ostriches. A stereological study was performed according to the Delesse principle. The mean volume fraction of the seminiferous tubules was 0.569, and the mean volume of the seminiferous tubules in an average testis was 1.04 cm3. The Paraffin-embedded sections were stained with hematoxylin and eosin, Masson’s trichrome, Alcian blue, and periodic acid–Schiff stains. Histological studies revealed that the spermatogonial stem cells and Sertoli cells were localized inside the seminiferous tubules, close to the basement membrane. Inside the tubules a few meiotic cells up to the spermatozoa stage were located in a centripetal manner. Outside the tubules, one to three layers of euchromatic peritubular myoid cells were present, surrounded by loose interstitial connective tissue. A thick tunica albuginea contained many myoid cells and some rete ducts, with the latter extending from the hilus to the free surface of the testis. Straight seminiferous tubules were distributed in the lateral surfaces and hilar portions of the capsule but were rare in the free surface. These capsular rete ducts may participate in testicular fluid transit from the distal tubules through the capsule.  相似文献   
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An internal cardioverter defibrillator (ICD) is normally extensively tested during implantation. The necessity of retesting prior to discharge of the patient is a matter of debate. In our material of 30 patients undergoing first-time implantation of a transvenous internal defibrillator system, we retrospectively compare the predischarge defibrillation test with the peroperative test. A successful peroperative defibrillation test with no failed shocks at 10 J below maximal energy level was followed by a successful predischarge test with the same safety margin in 18/19 patients, while one patient required a maximal energy ICD shock for conversion at the predischarge test. We conclude that the predischarge defibrillation test can be omitted if the peroperative test was successful, with no failed shocks at 10 J below maximal energy level and if the shock therapy is set to maximal energy level.  相似文献   
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Although the histological structure of ostrich testis has been studied, very little information is currently available on the embryonic development of this organ. The aim of this study was to determine the sequence of the histological changes in diverse components of the testis in ostrich embryo from embryonic day (E) 20 to E42. The main findings were categorized into four histological features, i.e., development of sex cords, interstitial tissue and rete ducts, and the appearance of defective septa. While the lumen of sex cords, tunica albuginea, capsular rete ducts and Leydig cell precursors appeared at E26, the filum-shaped defective septa were visible at E36. The emersion of the lumen in the primary sex cords and formation of capsular rete ducts in the ostrich embryo is considerably different from that in other birds. However, tunica albuginea and Leydig cell precursors appeared in a similar pattern to those of other birds. An interesting observation was that the primordial germ cell (PGC)-like cells were completely distinct, while the capsular rete ducts were formed by trapping of some Sertoli cell aggregations in the tunica albuginea. This suggests that similar to the primary sex cords, the capsular rete ducts may originate from the Sertoli cell aggregations which had corralled some PGCs. Stereological estimations in the ostrich embryo testis showed the major proportion of testis is occupied by the seminiferous tubules, which is unlike the fowl embryo testis.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Lesser Periwinkle (Vinca minor L.) is an important source of valuable secondary metabolites. To survey the...  相似文献   
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BackgroundIn February 2020, the Ministry of Health and Medical Education in Iran announced the first case of COVID-19. The aim of this study was to investigate the impact of COVID-19 on the number of CT-Scans and MRI services in public hospitals in western Iran.MethodsWe collected CT-scans and MRI services data from 18 public hospitals via Vice-Chancellor Office, Lorestan University of Medical Sciences from January 2017 to February 2021. Interrupted time series analysis (ITSA) was conducted to assess the impact of COVID-19 on CT-Scans and MRI services. More specifically, ITSA was conducted using ordinary least squares regression with the number of CT-Scans and MRI services per 1,000 registered persons per month as dependent variable.ResultsAt the beginning of the observation period, the monthly rate of CT-Scans was constant (p for trend = 0.267) at 291.9 (from 95%CI 240.5 to 343.4) per 1,000 registered patients. The first case of COVID-19 coincided with an abrupt increase by 211.8 (from 95%CI 102.9 to 320.7) per 1,000 patients. Thereafter, the trend of CT-Scans did not change (p=0.576) compared to the pre-pandemic period. The rate of MRI services was 363.5 per 1,000 per registered patients per month (P = <0.0001) with a slightly decreasing trend (coefficient=-5; 95%CI, -6.9 to -3.1).ConclusionThe findings of this study showed that crises such as COVID-19 can affect the service delivery process. Health policymakers and decision makers should work to prevent potential reductions in health care during events such as COVID-19.  相似文献   
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BackgroundThe standard agglutination (SAT) and 2-mercaptoethanol (2-ME) tests are usually used in the follow-up of treated cases of human brucellosis. The purpose of this study was to monitor the levels of these tests, two years after clinical cure in cases of brucellosis.MethodsFrom April 2003 to September 2008, 175 clinically cured cases of brucellosis (103 males, 72 females) were evaluated. Diagnosis of brucellosis was established with a SAT of ≥1:320 and a 2-ME of ≥1:80, with clinical symptoms and signs compatible with brucellosis. SAT and 2-ME were retested at the end of therapy and at 3-monthly intervals for two years. Serologic cure was considered in the event of a SAT titer decrease to ≤1:160 or a 2-ME decrease to < 1:80.ResultsThe mean age of study patients was 31 ± 13.5 years. At 6, 12, 18, and 24 months after treatment, SAT titers ≥1:320 were seen in 41 (23.4%), 22 (12.6%), 7 (4%), and 6 (3.4%) cases, respectively, whereas 2-ME titers ≥1:80 were seen in 51 (29.1%), 24 (13.7%), 12 (6.9%), and 8 (4.6%) cases, respectively. The probability of serologic cure for patients with SAT titers ≤1:640 was higher than for those >1:640 (95% confidence interval (CI) 2.5–3.47, p = 0.023). The probability of serologic cure for patients with 2-ME titers ≤1:320 was higher than for those >1:320 (95% CI 2.48–3.5, p = 0.04).ConclusionsSAT and 2-ME may be found in significant titers in less than 5% of clinically treated cases after two years. Serologic cure for both tests with lower titers were higher than with higher titers.  相似文献   
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