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81.
Solange Oliveira Juliana Aizawa Herbert Sousa Soares Daniela Pontes Chiebao Márcio Botelho de Castro Aline S. Hora Marcos Gomes Lopes Gereon Schares Mark C. Jenkins Oliver C.H. Kwok Ricardo Augusto Dias Solange Maria Gennari Jitender P. Dubey Hilda Fátima Jesus Pena 《International journal for parasitology》2018,48(2):117-123
The importance of birds in the biological cycle of Neospora caninum is not clear. We report unsuccessful Neospora infection in chickens (Gallus gallus domesticus) using two isolates of N. caninum. In experiment #1, 30 White Leghorn chickens were orally inoculated with viable N. caninum oocysts (NC-SP1 isolate, 200 oocysts per bird) via the crop at 21 days of age. Groups of three birds were euthanised at intervals of 7 days (a total of 9 weeks) and one group was challenged with the same oocyst dose at 37 days p.i. and observed for 11 weeks. Blood samples were collected weekly, and sera were tested using IFAT. Chicken tissues were collected for PCR, quantitative PCR and immunohistochemistry. Two dogs approximately 45 days of age were fed with tissues from chickens euthanised at 138 and 159 days p.i. The results indicated that the chickens were resistant to neosporosis as revealed by failure to seroconvert, to detect parasite DNA or N. caninum antigen by immunohistochemistry in inoculated bird tissues, and by no oocyst excretion by the dogs fed avian tissues. Similar results were obtained in experiment #2, in which 34 1-week-old chickens were each s.c. inoculated with 100,000 tachyzoites of the NcWTDMn1 isolate of N. caninum. The chickens were euthanised on days 7, 15, 22, 28, 36 and 60 p.i. At necropsy, all tissues and serum from each bird were collected. All chickens remained asymptomatic, and N. caninum antigen was not detected by immunohistochemistry. Seven chickens euthanised at day 60 p.i. demonstrated low (1:25 dilution) levels of antibodies by using the Neospora agglutination test. Two 12-week-old dogs fed tissues pooled from 10 inoculated chickens euthanised at day 60 p.i. did not excrete N. caninum oocysts. This investigation indicates that chickens are resistant to experimental infection by N. caninum. 相似文献
82.
Manuel-Angel Dueñas Holly J. Ruffhead Nicola H. Wakefield Philip D. Roberts David J. Hemming Hilda Diaz-Soltero 《Biodiversity and Conservation》2018,27(12):3171-3183
Invasive species are considered to be a leading cause of the decline of threatened species. However, this view has been disputed because much of the evidence base is anecdotal. This systematic review, through an extensive, repeatable search using agreed selection criteria, examined the available scientific evidence on invasive species’ interactions with the 1363 endangered and threatened species protected under the United States Endangered Species Act (ESA). The review found scientific evidence available for 116 endangered or threatened species (8.5% of the ESA list). Of these, 85 species (6.2%) were reported as being negatively impacted by invasive species: 39 located on the continental US and 39 on islands, with seven marine species. The relative percentages of species impacted differed according to location: 4.3% (n?=?906) on the continental US, 9.3% (n?=?420) on islands. It was found that predation by invasive vertebrates on birds on islands and competition between invasive plants and endangered or threatened plants on the mainland were the main mechanisms of impact. The results of this study contrast markedly with a previous study which found that 49% of imperilled species in the United States were threatened by invasive species. Further research is essential in order to evaluate the impact of invasive species on imperilled species on the ESA list; this would help to reduce the high degree of uncertainty regarding the threat of invasive species due to the lack of empirical information. 相似文献
83.
Hilda?Amekyeh Nashiru?BillaEmail author Kah-Hay?Yuen Sheau Chin?Sherlyn?Lim 《AAPS PharmSciTech》2016,17(5):1060-1066
Amphotericin B (AmB) is poorly absorbed from the gastrointestinal tract. Recent studies have suggested enhanced drug absorption from solid lipid nanoparticles (SLN). Little is known of the fate of AmB absorption within the gastrointestinal tract, and no gastrointestinal transit study has yet been performed on AmB-containing nano-formulations. We aimed to investigate the effect of food on the gastrointestinal transit properties of an AmB-containing SLN in rats. Three SLNs containing AmB, paracetamol, or sulfasalazine were formulated using cocoa butter and beeswax as lipid matrices and simultaneously administered orally to Sprague-Dawley rats. Paracetamol and sulfapyridine were used as marker drugs for estimating gastric emptying and cecal arrival, respectively. The pharmacokinetic data generated for paracetamol and sulfapyridine were used in estimating the absorption of the AmB SLNs in the small and large intestines, respectively. A delayed rate of AmB absorption was observed in the fed state; however, the extent of absorption was not affected by food. Specifically, the percentages of AmB absorption during the fasted state in the stomach, small intestine, and colon were not significantly different from absorption within the respective regions in the fed state. In both states, however, absorption was highest in the colon and appeared to be a combination of absorption from the small intestine plus absorption proper within the colon. The study suggests that AmB SLN, irrespective of food status, is slowly but predominantly taken up by the lymph, making the small intestine the most favorable site for the delivery of the AmB SLNs. 相似文献
84.
85.
Ibrahim Zaganjor Ahlia Sekkarie Becky L. Tsang Jennifer Williams Hilda Razzaghi Joseph Mulinare Joseph E. Sniezek Michael J. Cannon Jorge Rosenthal 《PloS one》2016,11(4)
BackgroundFolate-sensitive neural tube defects (NTDs) are an important, preventable cause of morbidity and mortality worldwide. There is a need to describe the current global burden of NTDs and identify gaps in available NTD data.ConclusionsMany WHO member states (120/194) did not have any data on NTD prevalence. Where data are collected, prevalence estimates vary widely. These findings highlight the need for greater NTD surveillance efforts, especially in lower-income countries. NTDs are an important public health problem that can be prevented with folic acid supplementation and fortification of staple foods. 相似文献
86.
In 12 months'' use of a mobile unit for cervical and breast cancer screening in Gloucestershire 3,211 women attended at an average of five sessions a week. Clinic sessions were organized and the running costs of the service met by a voluntary organization. The keeping of records, provision of laboratory facilities, and the follow-up of patients were carried out in close cooperation with the county health department. 相似文献
87.
Hilda Geiringer 《Bulletin of mathematical biology》1949,11(3):197-219
In the first part of this paper, hereinafter referred to as I, a general segregation, distribution was introduced for autopolyploids
(2s-ploids) withm, loci, andr alleles. Random mating, chromosome segragation, distinct generations, and equal segregation distributions for males and females
were assumed. In this second part, using this segregation distribution as a basis, a recurrence formula is established which
enables us to compute the distribution of gametes for any generation, if this distribution is known for an initial generation.
This initial distribution of gametes is derived from the initial distribution of genotypes. The limit behavior of these distributions
is completely described in a general limit theorem which contains as particular cases the limit theorems for diploids withm loci, and for 2s-ploids with one locus (Geiringer, 1944, 1945, 1948). 相似文献
88.
Hilda Geiringer 《Bulletin of mathematical biology》1949,11(2):59-82
A theory of linkage of autopolyploids is developed under consideration ofm loci andr alleles. The simplifying assumption of chromosome segregation, which may be considered as an approximation to the more adequate
theory of chromatid segregation, is made throughout. Random mating and distinct, non-overlapping generations are assumed.
Under these assumptions the problem is determined by three basic probability distributions—the distributions of genotypes
and of gametes, and the segregation distribution. The segregation distribution is assumed to be the same for males and for
females. The aim of the paper is to establish recurrence formulas (which allow to find the distributions of gametes and of
genotypes from generation to generation, if the distribution of genotypes for an initial generation is known) and to investigate
the limit behavior of these distributions as the number of generations increases indefinitely.
In the present paper (hereafter referred to as I) the problem is explained, and the three characteristic distributions are
introduced for the general case of a 2s-ploid,m loci, andr alleles. Recurrence relations are established for tetraploids,s=2 andm=2 loci, while the recurrence relations for the general case as well as the limit theorems will be given in the second part
of this paper (hereafter referred to as II). 相似文献
89.
90.
Hilda Ritter-Studnička 《Plant Systematics and Evolution》1965,112(3):371-391
Ohne Zusammenfassung 相似文献