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1.
Of a total of 2392 fungi isolated from weevil-damaged pecans, 46.4% were Alternaria and Epicoccum, 23.9% were Penicillium, 12.4% were Pestalotia and Monochaeta, 6.5% were Cladosporium, 6.4% were Fusarium, and less than 2% each were Phoma, Aspergillus, Rhizopus, Trichothecium, and miscellaneous. Chloroform extracts of 34 of 105 representative Penicillium isolates, 3 of 28 Fusarium isolates, and 3 of 23 Aspergillus isolates were toxic to day-old cockerels during three bioassays. Eight of the toxic extracts from Penicillium spp. were tremorgenic. One tremorgenic isolate was identified as P. paxilli, four were identified as P. lanoso-coeruleum, and three as P. cyclopium. Nine of the non-tremorgenic isolates were identified as P. citrinum, five as P. aurantio-virens, three as P. oxalicum, and two as P. meleagrinum. Others were identified as one each of P. brevi-compactum (Series), P. nigricans (Series), P. roqueforti, P. rugulosum (Series), P. terrestre, and P. stoloniferium. One was unidentified. Toxigenic Aspergillus isolates were all A. flavus. Two of the toxic Fusarium isolates were F. moniliforme, and one was unidentified.  相似文献   

2.
Phylogeny of Ephemeroptera (mayflies) based on molecular evidence   总被引:1,自引:0,他引:1  
This study represents the first molecular phylogeny for the Order Ephemeroptera. The analyses included 31 of the 37 families, representing approximately 24% of the genera. Fifteen families were supported as being monophyletic, five families were supported as nonmonophyletic, and 11 families were only represented by one species, and monophyly was not testable. The suborders Furcatergalia and Carapacea were supported as monophyletic while Setisura and Pisciforma were not supported as monophyletic. The superfamilies Ephemerelloidea and Caenoidea were supported as monophyletic while Baetoidea, Siphlonuroidea, Ephemeroidea, and Heptagenioidea were not. Baetidae was recovered as sister to the remaining clades. The mayfly gill to wing origin hypothesis was not supported nor refuted by these data. Mandibular tusks were supported as having at least one loss in Behningiidae and, together with the burrowing lifestyle, possibly two origins. The fishlike body form was supported as plesiomorphic for mayflies with multiple secondary losses. Topological sensitivity analysis was used as a tool to examine patterns concerning the stability of relationships across a parameter landscape, providing additional information that may not have been acquired otherwise.  相似文献   

3.
Variability in Race Tests with Heterodera glycines   总被引:1,自引:0,他引:1  
Tests of Heterodera glycines on differential host plants to determine races were run in Arkansas, Illinois, and North Carolina to check the uniformity of results of the test. Methods used at the three locations varied somewhat. Results indicate that the race test is highly variable. Isolates previously identified as race 1 were identified as race 1 or race 3; those identified as race 2 were identified in these tests as race 2, 4, 9, or 14; those previously identified as race 3 were identified as race 1 or race 3; those identified as race 4 were identified in these tests as race 4 or race 14; those previously identified as race 5 were identified as race 2; and those previously identified as race 6 were identified as race 1, 2, 4, 5, or 6. Part of the variability resulted from the use of differential host plants from different sources and part from nonstandard differential host plants. Other variations may be due to inability to obtain completely uniform inoculum or to recover all nematodes that penetrated.  相似文献   

4.
激活蛋白处理水稻引发基因差异表达的研究   总被引:2,自引:0,他引:2  
利用抑制性消减杂交技术(Suppression Subtractive Hybridization,SSH)成功构建了植物激活蛋白处理水稻与非处理组水稻中差异表达的消减cDNA文库。从文库中一共筛选到1756个克隆,通过反向Northern杂交,从中得到264个有效克隆并测序,利用BLAST在GenBank数据库进行序列相似性比对分析,获得28个上升表达差异基因。通过分析这些基因与植物的光合作用、营养物质的运输代谢等多种植物的生理生化功能相关。本研究为揭示激活蛋白的作用机理奠定基础。  相似文献   

5.
Reproductive records of 284 female rhesus monkeys housed in six multimale corrals at the California Primate Research Center were examined for the birth seasons 1977–1982 to determine possible associations between the probability of birth or live birth and female age, parity, origin, parturition in the previous season, infant birth date, and infant birth date in previous season. Multiple logistic regression analysis was used to identify and quantitate the effects of factors on the probability of birth or live birth, while controlling for the possibly confounding effects of other factors in the model. Females who had infants early in the previous season were 2.5 times as likely to give birth as those who had infants late in the previous season. Females with two or three previous births were 2.1 times as likely to give birth, and those with four or five previous births were 6.7 times as likely to give birth as were females with no or one previous birth. Controlling for other factors (age, parity, and timing of birth in the previous season), corralborn females were 3.3 times as likely to give birth as either wild-caught or domestic-born monkeys not native to the corrals. Domestic-born females who were not corral natives were 0.3 times as likely to have live births as wild-caught females. Births late in the season were 1.8 times as likely to result in live infants as births early in the season.  相似文献   

6.
OBJECTIVE: To study fine needle aspiration (FNA) cytological findings of splenic lesions and assess the role of FNA in the diagnosis of splenomegaly or splenic tumours. METHODS: This study consisted of 48 cases, 25 males and 23 females. The ages ranged between 3 and 71 years. Most of these cases were aspirated under ultrasonographic guidance and a small number were also aspirated directly by using a 22- to 23-gauge needles. The smears were stained with Wright-Giemsa and Papanicolaou methods. Special stains were used whenever necessary. RESULTS: In this study 14 cases were diagnosed as lymphoma-leukaemia, 7 cases as tuberculosis, 12 cases as kala-azar, 2 cases as hydatid cyst, 3 cases as storage diseases, 3 cases as simple cyst, 2 cases as myeloproliferative disorders, 2 cases as malignant tumours and 3 cases as hamartomas (these were wrongly diagnosed as malignant tumours). CONCLUSION: Splenic aspiration is a safe procedure and is very useful in the diagnosis of parasitic and infectious diseases, especially in endemic countries like Iran.  相似文献   

7.
Phylogenetic relationships within Celastraceae were inferred using a simultaneous analysis of 61 morphological characters and 1123 base pairs of phytochrome B exon 1 from the nuclear genome. No gaps were inferred, and the gene tree topology suggests that the primers were specific to a single locus that did not duplicate among the lineages sampled. This region of phytochrome B was most useful for examining relationships among closely related genera. Fifty-one species from 38 genera of Celastraceae were sampled. The Celastraceae sensu lato (including Hippocrateaceae) were resolved as a monophyletic group. Loesener's subfamilies and tribes of Celastraceae were not supported. The Hippocrateaceae were resolved as a monophyletic group nested within a paraphyletic Celastraceae sensu stricto. Goupia was resolved as more closely related to Euphorbiaceae, Corynocarpaceae, and Linaceae than to Celastraceae. Plagiopteron (Flacourtiaceae) was resolved as the sister group of Hippocrateoideae. Brexia (Brexiaceae) was resolved as closely related to Elaeodendron and Pleurostylia. Canotia was resolved as the sister group of Acanthothamnus within Celastraceae. Perrottetia and Mortonia were resolved as the sister group of the rest of the Celastraceae. Siphonodon was resolved as a derived member of Celastraceae. Maytenus was resolved as three disparate groups, suggesting that this large genus needs to be recircumscribed.  相似文献   

8.
DNA restriction endonuclease analysis for genome typing of adenovirus (Ad) DNA was carried out on a total of 65 Ad isolates including serotypes Ad4, Ad7, Ad8, Ad11, Ad19, and Ad37 from patients with epidemic keratoconjunctivitis and acute conjunctivitis obtained in Japan from 1982 to 1986, Australia from 1973 to 1986, and the Philippines in 1984. All 4 isolates of Ad7 in Australia were Ad7b. Four of 6 Ad11 isolates obtained in Japan were typed as Ad11 prototype (Ad11p), and the remaining were identified to be new genome types, designated tentatively as Ad11c and Ad11d. An isolate of Ad11 obtained in Australia was typed as Ad11c. Nine Ad8 isolates in Australia and in the Philippines were typed as Ad8p, but 11 Ad8 isolates in Japan were Ad8b. Thirteen Ad19 isolates were identified as Ad19a. All 3 isolates of Ad37 in Japan and three isolates in Australia before 1982 were typed as Ad37p, however, 5 isolates in Australia after 1983 were identified as a new genome type, designated as Ad37d. In Japan, 10 isolates of Ad4 were identified as Ad4a.  相似文献   

9.
The parameters involved in the action of beta-galactosidase (EC 3.2.1.23) (Escherichia coli) on allolactose, the natural inducer of lac operon in E. coli, were studied. At low allolactose concentrations only galactose and glucose were formed, while at high allolactose concentrations transgalactolytic oligosaccharides were also produced. Detectable amounts of lactose were not formed. The V and Km values (49.6 U/mg and 0.00120 M, respectively) indicated that allolactose is as good if not a better substrate of beta-galactosidase as lactose. The pH optimum with allolactose (7.8-7.9) as well as its activation by K+ (as compared to activation by Na+) were similar to the case with lactose as substrate. The alpha-anomer of allolactose was hydrolyzed about two times as rapidly as was the beta-anomer.  相似文献   

10.
Seventy-one fungicides were mixed with an artificially infested soil/peat mixture in which cabbage seedlings were subsequently grown in pots in a glasshouse. The incidence and severity of clubroot and any toxic effects on the plants were recorded. Carbendazim, chloraniformethan, maneb, ferbam, zinc N-methyl dithiocarbamate, zinc diethanolamine dithiocarbamate and ziram were selected as suitable for further evaluation as they gave disease control as good as the standard calomel treatment and were of comparably low phototoxicity.  相似文献   

11.
Production of Reference Enteroviruses   总被引:1,自引:1,他引:0       下载免费PDF全文
Forty-five human enterovirus reagents of certified purity and quality were prepared for use as seed viruses and as immunizing antigens. One of the reagents was ampouled as "untreated" seed virus, whereas 14 were ampouled as "MgCl(2)-stabilized" reagents. The remaining 30 reagents were ampouled as "untreated" seed viruses and as "MgCl(2)-stabilized" reagents. Thirty of the reagents were propagated on primary African green monkey kidney cells, 3 on primary baboon kidney cells, 3 on primary rhesus monkey kidney cells, and the remaining 9 on human amnion cells. Forty-two of the viral antigens were concentrated for use in the production of high-titered specific antisera in large animals.  相似文献   

12.
健康仔猪肠道乳杆菌黑龙江地方株的鉴定与种属分析   总被引:2,自引:1,他引:1  
为了从健康仔猪肠道中分离筛选用于研制微生态制剂的乳酸杆菌菌株,选择黑龙江省大庆、哈尔滨及宝泉岭地区部分猪场,采集12-60日龄健康仔猪肠道粪样64份。选用MRS乳酸杆菌专用培养基分离培养乳酸杆菌,通过分离株的形态特征和培养特性筛选出革兰阳性,厌氧,无芽胞杆菌48株。再通过生化试验鉴定和PCR种属分析,确定18株为乳酸杆菌。其中,罗伊乳杆菌7株,嗜酸乳杆菌5株,约氏乳杆菌2株,短乳杆菌1株,干酪乳杆菌假植物亚种1株,植物乳杆菌1株,詹氏乳杆菌1株。  相似文献   

13.
A eucaryotic cell assay was established to identify novel, dual and selective inhibitors of human 5alpha-reductase. For this purpose the cDNAs encoding 5alpha-reductase type I and type II were inserted into a pRcCMV vector and expressed in human embryonic kidney (HEK293) cells. Single cell clones with substantially high enzymatic activity were selected and established as permanent cell lines. KM values were determined for both isozymes. The inhibitory potency of several steroidal and non-steroidal compounds synthesized in our group, as well as finasteride and 4MA as controls, were tested by measuring the conversion of [3H]androstenedione. Reaction products were quantified by a HPLC reversed phase technique. Using the new cell assays, selective as well as novel dual 5alpha-reductase inhibitors with IC50 values between 1.0 and 2.5 microM were identified.  相似文献   

14.
In an evaluation of the efficacy of cerebrospinal fluid (CSF) examination in our laboratory, 1,635 CSF specimens received between March 1, 1975, and December 31, 1982, were reviewed. All 111 positive samples (from 77 cases) and all 141 suspicious samples (from 83 cases) were reviewed microscopically, and the clinical records in the cases were rechecked. The 77 positive cases were confirmed by tissue and other studies: 23 as primary brain tumors, 26 as secondary carcinomas, 14 as leukemias, 12 as lymphomas and 2 as multiple myelomas. The 83 suspicious cases were similarly confirmed: 31 as primary brain tumors, 14 as secondary carcinomas, 22 as leukemias and 7 as lymphomas-with 9 found to be "benign." There were no false positives in the positive group. This study suggests that the identification of malignant cells in CSF samples constitutes a reliable method of diagnosis and lessens the need for further biopsies.  相似文献   

15.
A method for purification of enzymes from the ligninolityc complex of the basidiomycete Trametes pubescens (Schumach.) Pilat has been elaborated. Two homogeneous isoforms of laccases (laccase 1 and laccase 2) as well as a homogeneous preparation of lignin peroxidase were isolated. Basic biochemical parameters of the enzymes were determined, such as the molecular weights (67, 67, and 45 kD, respectively), isoelectric points (5.3, 5.1, and 4.2, respectively), as well as content and composition of the carbohydrate moiety of the laccases (N-acetylglucosamine, mannose, and xylose). The pH dependences and thermal stabilities of the laccases were investigated. The kinetic parameters of the enzymatic reactions catalyzed by the laccases were determined using different substrates, such as catechol, hydroquinone, 2,2 -azinobis-(3-ethylbenzthiazoline-6-sulfonate), and K4Fe(CN)6. The structure of the active sites of both laccases and the lignin peroxidase were studied by EPR, CD, and UV-VIS spectroscopy, as well as using fluorescence analysis. Our studies showed similarity of the spectral characteristics of the two laccases, whereas their kinetic properties were found to be different.  相似文献   

16.
The partially degraded lipopolysaccharide of Burkholderia cepacia (LPSdegr) and the ornithine-containing lipids were purified from some bacteria. The substances were developed as complex lipid adjuvants, because they have weak toxicity and are able to activate the immune systems of the living body. After various toxoid antigens such as pertussis toxoid, diphtheria toxoid and tetanus toxoid were mixed with the complex lipid adjuvants, the mixtures were administered to mice subcutaneously. Antitoxoid IgG antibody titers in the serum were measured several times over 3 months. The efficacy of the LPSdegr as adjuvant was almost as high as that of the ornithine-containing lipids, and it was almost equal to that of the aluminum hydroxide adjuvant (Alum), which is generally used as a vaccine adjuvant.  相似文献   

17.
为了探究孟高棉语族未识别民族族群特征,研究组以412名(男性220人,女性192人)云南孟高棉语族未识别民族成人为例,运用人体测量学方法对该族群男女头面部与体部58项指标及20个指数进行测量和分析,并选取头长、头宽、面宽、形态面高、身高、坐高、肩宽、骨盆宽8项指标与30个已研究族群进行比较。结果表明:1)男性各项体质指标除大腿围和6项皮褶厚度指标外,都大于女性各项指标,男女身高均以矮型为主;2)孟高棉语族未识别民族男性上眼睑皱褶率为88.2%,女性上眼睑皱褶率为94.3%。男性蒙古褶率为41.8%,女性蒙古褶率为36.5%。鼻根高度男性以中等型为主,女性以低平为主。耳垂类型男性以圆形率为主,女性以三角形率为主;3)依据指数分型出现率得出:孟高棉语族未识别民族男女均以圆头型、高头型、阔头型、狭鼻型、中腿型、中胸型、宽肩型率最高;4)聚类分析和主成分分析显示孟高棉语族未识别民族与布朗族、基诺族、布依族、侗族比较接近。遗传因素、环境条件与饮食习惯是这些民族体质特征接近的原因。  相似文献   

18.
生物反应器法处理PAHs污染土壤的研究   总被引:15,自引:2,他引:13  
利用自行设计的生物泥浆反应器研究了多环芳烃 (PAHs)污染土壤生物修复技术 .结果表明 ,在相同环境条件下 ,污染物自身的理化性质是影响生物修复的关键因素 ,苯环越多、分子量越大 ,越难以被微生物利用 ,故菲 (PHE)比芘 (PY)具有更高的污染可修复性 .温度、空气流量是重要的调控因子 .本实验中 ,生物泥浆反应器处理PAHs污染土壤选择的最佳运行工艺参数是 :温度 2 0~ 30℃ ,水土比 2∶1,空气流量8L·h-1·L-1,接种量 5 0g·kg-1.该工艺参数为生物泥浆反应器技术实用化及其他相关研究工作的深入开展提供了理论依据  相似文献   

19.
Summary H-Y-antigen expression was analyzed in patients with transsexuality. Peripheral blood lymphocytes and various tissues were examined using the cytotoxicity assay of Goldberg et al. (1971). Peripheral blood lymphocytes from healthy male and female subjects were used as controls as well as tissues from nontranssexual individuals and from male and female C57Bl/6J mice. In three female-to-male transsexuals the peripheral blood lymphocytes were H-Y antigen positive. In these patients also their ovaries, uterus, and mammae were found to be H-Y antigen positive. Three male-to-female transsexuals were examined. The peripheral blood lymphocytes in two of these patients were found to be H-Y antigen negative. Their testes were also H-Y antigen negative, as well as the epididymus, the corpus cavernosum penis, and the cremaster muscle which was analyzed in one of them. One male-to-female transsexual had peripheral blood lymphocytes which were H-Y antigen positive; this patient had testis and corpus cavernosum penis which were also H-Y-antigen positive.  相似文献   

20.
本文报导了葱鳞葡萄孢菌(Botrytis squamosa)的异核现象。采用荧光染色法证实了该菌的分生孢子和菌丝细胞均是多核的。以该菌的自然形态和生长特征为遗传标记,在193个单孢子培养物中获得了三种菌型:菌核型(S)、菌丝型(M)、界于菌核和菌丝之间的菌核菌丝型(SM)。SM型在形态上与原始菌株相同。S型和M型在连续的传代过程中其特征保持稳定,因而被认为是同核型。SM型在连续传代过程中是不稳定的,且一再分离出S型和M型,因此被认为是异核型。用传代稳定的S型和M型重新合成的异核体在特征上相同于原始菌株和SM型。用这个合成的异核体再次进行单孢子分离,三种菌型重新被获得。三种菌型在致病力方面没有表现出显著的差异。  相似文献   

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