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排序方式: 共有90条查询结果,搜索用时 15 毫秒
1.
Adenovirus SV-20 (ASV-20) was inoculated subcutaneously into adult rhesus macaques (Macaca mulatta), and various immunologic parameters were studied. Similar changes were observed in macaques that had anti-ASV-20 serum-neutralizing antibodies prior to inoculation and in those lacking detectable antibodies. There were absolute decreases in numbers of peripheral blood lymphocytes (PBL), erythrocyte-rosetting lymphocytes, complement-receptor lymphocytes, and Fc-receptor lymphocytes. These changes were most significant (P less than 0.05) on postinoculation days (PID) 3 and 7. Mitogenic responsiveness to concanavalin A, phytohemagglutinin, and pokeweed mitogen in cultured PBL from immune and nonimmune macaques was depressed on PID 3, 7, and 14. Ultraviolet-inactivated ASV-20 caused moderate suppression of phytohemagglutinin-induced mitogenesis when viral particles and lectin were added simultaneously to PBL cultures. Plasma cortisol (hydrocortisone) values were not significantly altered following inoculation of ASV-20. High titers of anti-ASV-20 antibody developed by PID 7 in nonimmune macaques, and previously immune macaques showed a booster effect in the same time period. Antibody titers were still increased 120 days after inoculation. There was no clinical evidence of an adverse effect of ASV-20 infection in these macaques.  相似文献   
2.
Myanmar indigenous chickens play important roles in food, entertainment, and farm business for the people of Myanmar. In this study, complete mitochondrial D-loop sequences (1232 bp) were analyzed using 176 chickens, including three indigenous breeds, two fighting cock populations, and three indigenous populations to elucidate genetic diversity and accomplish a phylogenetic analysis of Myanmar indigenous chickens. The average haplotype and nucleotide diversities were 0.948 ± 0.009 and 0.00814 ± 0.00024, respectively, exhibiting high genetic diversity of Myanmar indigenous chickens. Sixty-four haplotypes were classified as seven haplogroups, with the majority being haplogroup F. The breeds and populations except Inbinwa had multiple maternal haplogroups, suggesting that they experienced no recent purifying selection and bottleneck events. All breeds and populations examined shared haplogroup F. When 232 sequences belonging to haplogroup F (79 from Myanmar and 153 deposited sequences from other Asian countries/region) were analyzed together, the highest genetic diversity was observed in Myanmar indigenous chickens. Furthermore, Myanmar indigenous chickens and red junglefowls were observed in the center of the star-like median-joining network of 37 F-haplotypes, suggesting that Myanmar is one of the origins of haplogroup F. These findings revealed the unique genetic characteristic of Myanmar indigenous chickens as important genetic resources.  相似文献   
3.
The urinary enzyme markers of renal damage, alkaline phosphatase (AP), gamma-glutamyl transferase (GGT) and N-acetyl-beta-glucosaminidase (NAG), glomerular filtration rate (GFR) and renal biopsies were studied to evaluate renal status in dogs with pyometra. After ovariohysterectomy, urinary enzymes were measured daily for 12 days in 55 dogs, and again at a later follow-up visit. Thirteen dogs had high levels of at least one enzyme at initial presentation. Seventeen dogs had a transient increase in urinary enzyme values between one and five days after surgery. Enzyme values usually declined to low activities within 12 post-operative days. Renal biopsies demonstrated tubular abnormalities in many dogs. Mean GFR was 2.4 and 2.0 ml min(-1) kg(-1), respectively on day 1 post-operatively and at the follow-up visit 1-4 months later. High urinary enzyme values often reflected extensive lesions in renal proximal tubular cells and sometimes reduced GFR.  相似文献   
4.
Rhesus monkey fetuses of either immune or nonimmune dams were inoculated in utero with Adenovirus SV-20 (AdSV-20), a virus capable of inducing fetal pneumonia, and studied immunologically at various intervals. AdSV-20 infection at 90–100 days gestational age resulted in absolute lymphopenia in a few fetuses, reduced numbers of peripheral blood lymphocytes (PBL) which formed rosettes with sheep erythrocytes (ERL) and reduced complement-receptor lymphocytes (CRL) in a majority, while Fc fragment-receptor lymphocytes (FcRL) were occasionally increased. There was a tendency for depression of ERL and CRL early in infection of 120–130-day fetuses, followed by stimulation of these populations and FcRL in later phases. Maternal immunity did not protect against these effects of AdSV-20 infection in fetuses. Immune and nonimmune dams were spared adverse clinical effects and had no changes in lymphoid cell populations following inoculation of their fetuses.Despite precocious production of circulating IgM, fetuses of nonimmune dams had little or no demonstrable anti-AdSV-20 serum neutralizing (SN) antibody, indicating that the ability to develop an effective immune response was suppressed or had not been acquired at the gestational ages studied. Nonimmune dams displayed little evidence of seroconversion following inoculation of their fetuses with AdSV-20, except in those dams whose fetuses died in utero, whereby there was a significant antibody response. SN antibody titers of immune dams were not boostered substantially subsequent to inoculation of their fetuses, and fetal SN titers were lower than maternal titers, suggesting absence of an active fetal antibody response in this group also. Direct inoculation of AdSV-20 into 90–130-day rhesus monkey fetuses provided a model system for immunologic study of fetal infection, probably involving complex fetal-maternal interactions, in a situation where the infected, viable fetus and its dam appeared to be microbiologically isolated from one another.  相似文献   
5.
ABSTRACT:     Sexual maturity, morphological sexual dimorphism, and reproduction of the goneplacid crab Carcinoplax vestita were investigated in Tokyo Bay, Japan, from November 2002 to October 2003. The puberty molt in males was evidenced by changes in the relative size of the chelipeds and merus of the walking legs, and was estimated to occur at a size range of 13.20–18.85 mm carapace length. Post-pubertal females were identified by the relative size of the abdomen and puberty was estimated to occur at a size range of 12.81–15.46 mm carapace length. Sexual dimorphism in C. vestita was observed in all features that showed secondary sexual characteristics. Monthly changes of gonad index in males, and of seminal receptacle index and occurrence of sperm plugs in females were synchronized, and indicated that mating was intense in spring. Ovaries began developing in March. Ovigerous females were found in all months except December, but were clearly more abundant between August and October. Fecundity ranged from 7800 to 57 000 mature oocytes per female per batch and was highly correlated with body size. The results suggest that some females may spawn more than one batch per year.  相似文献   
6.
An eight-year-old dog with a local relapse of an osteosarcoma was treated with partial maxillectomy and systemic radionuclide therapy that involved two injections, 43 and 45 megabec-querels per kg bodyweight of the bone-seeking agent samarium-153-ethylenediaminetetramethy-lene phosphonic acid (153Sm-EDTMP), 15 weeks apart. A transient drop in white blood cell count and platelet count was observed following each 153Sm-EDTMP treatment. Follow-up 21 months after surgery revealed no evidence of local recurrence or metastases. The dog was in excellent condition, suffering only minor sequelae from the surgical procedure. Compared with historical controls treated with surgery alone, the combination of surgery and systemic radionuclide therapy seems a promising strategy for the treatment of canine osteosarcoma.  相似文献   
7.
The clinical findings In German shepherd dogs with hereditary multifocal renal cystadenocarcinomas and nodular dermatofibrosis are presented. Between 1978 and 1996, 51 cases were examined. Eight cases were detected after being offered a clinical examination because the disease was present in a parent. The remaining 43 dogs were diagnosed after an unsolicited visit to a clinic because of a specific problem. Skin lesions were the main reason (37 per cent) the owners presented their dog for examination. The mean age at diagnosis of renal cystadenocarcinomas and nodular dermatofibrosis was 8-2 years. The male-to-female ratio was 1-1, while the corresponding figure for a reference population was 1–25. Enlarged and abnormally shaped kidneys were palpated In 60 per cent of the dogs and were detected by radiography in 86 per cent of cases. The renal lesions, including metastases, were the main reason for euthanasia and death. The mean age at death was 9-3 years, and the mean age at the first detection of nodular dermatofibrosis was 6-4 years.  相似文献   
8.
The main objective of this study was to study risk factors affecting metaphyseal irregularities (MI) in the distal radius and ulna of growing Newfoundland dogs. Risk factors studied included the genetic effects, effects of litters, BW, circumferences of the distal radius and ulna (CDRU), and total serum alkaline phosphatase (ALP) concentrations. The study included 118 Newfoundland dogs (60 females, 58 males), derived from 32 litters. Body weight, separated on sex and MI, was fitted to the Gompertz function. Occurrence of MI differed significantly between sexes, with 55% of males and 35% of females affected (P = 0.03). Growth curves for the 2 groups of dogs, with and without MI, diverged after 60 to 70 d, and dogs with irregularities were heavier at maturity than dogs of the same sex without irregularities. In univariate analysis, the litter effect was a significant predictor of MI, explaining 32% of total variability of the MI incidence, but the genetic effects were not significant. However, the latter were significant in bivariate analysis of MI and BW. In the bivariate analysis, the effects of litter on MI and BW were significantly correlated at all observational points except at birth, 180 d, and 536 d. Total ALP concentrations decreased with increasing age, and differences between groups diminished with increasing age, indicating a negative effect of total ALP on MI. Correlation between MI and total ALP concentrations of litters was estimated in a bivariate analysis. This correlation was significant and ranged between -0.34 and -0.62. Similarly, the genetic relationship between total ALP and MI from 120 d of age onward varied between -0.31 to -0.60. However, correlations were only significant at 356 d of age (genetic correlation = 0.60; P = 0.01). The mean CDRU increased from 90 d of age toward a peak at 180 d. Thereafter, CDRU declined and stabilized at about 1 yr of age. The mean CDRU between the groups of dogs with and without MI diverged most at 90 d of age, then was nearly stable until 180 d and gradually declined until 356 d, when the CDRU began to equalize. Metaphyseal irregularities and CDRU levels of litter were significantly correlated. Litter effect was a significant predictor of MI. The effects of litters and the genetic effects on BW and MI were correlated at most phases of the growth of the dog. Similar, but lower, correlations were found for CDRU and MI, and total ALP and MI.  相似文献   
9.
The main objective of this study was to describe the growth patterns of 4 large dog breeds [Newfoundland (NF), Labrador retriever (LR), Leonberger (LEO), and Irish wolfhound (IW)] raised in domestic environments and concomitant changes in 2 growth-related clinical variables: total serum alkaline phosphatase (ALP) and the circumference of the distal radius and ulna (CDRU). The second objective was to investigate whether these measurements were affected by a range of independent variables like age, sex, litter number, and birth weight. Seven hundred dogs were included in the study, and BW data, separated by breed and sex, were fitted to the Gompertz function. Birth weight, adjusted for litter number, differed significantly between sexes for 3 breeds (LEO, P = 0.004; NF, P = 0.02; LR, P = 0.009) and approached significance for IW (P = 0.07). Estimated mean BW increased rapidly during the first 100 d after birth in all 4 breeds, then plateaued, with maturity being reached between 351 (female LR) and 413 d (male NF). Estimated mature BW ranged from 30.8 kg for the female LR up to 65.7 kg for the male IW. Weight gain, as expressed by the derivative of the Gompertz function, reached its peak in the smallest breed (LR) at the youngest age, 89 d for the females and 95 d for males. Log-transformed BW was significantly related to age, breed, and sex, and the age x sex and age x breed interactions. Within breeds, age, birth weight, and litter number had a significant effect on log-transformed BW. The estimated average CDRU increased from 90 d of age toward a peak at 180 d. Thereafter, CDRU declined and stabilized at about 1 yr of age. The estimated total ALP concentrations decreased from 90 to 360 d of age, after which they stabilized, at mean concentrations varying among breeds from 98 to 131 IU/L. Maximum least squares mean total ALP concentrations were found at 3 mo of age in all breeds, with the greatest least squares mean concentration in the IW breed (713 IU/L). In a mixed model analysis of the complete data set, total ALP was affected (P < 0.001) by age, breed, and the interaction of age x breed. This study described the main factors influencing growth and provided reference data for other studies, including those related to nutrition and disorders of growth.  相似文献   
10.
Moe RL  Silva PC 《Science (New York, N.Y.)》1977,196(4295):1206-1208
The discovery of embryonic stages of the common large Antarctic brown seaweed Himantothallus has led to the conclusion that this plant, hitherto assigned equivocally to the Laminariales (kelps), is a member of the Desmarestiales. Moreover, field study of a large sample of Himantothallus and two other enigmatic brown algae, Phyllogigas and Phaeoglossum, has led to the merger of these three genera with the recognition of a single species, Himantothallus grandifolius. The correct placement of these kelp-like algae underscores the uniqueness of the Antarctic marine flora as the only cold-water flora without kelps.  相似文献   
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