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61.
Background:  In dogs, the gastric Helicobacter spp. have been well studied, but there is little information regarding the other parts of the alimentary system. We sought to determine the spatial distribution of Helicobacter spp. in the gastrointestinal tract and the hepatobiliary system of dogs using culture-independent methods.
Materials and methods:  Samples of stomach, duodenum, ileum, cecum, colon, pancreas, liver, and bile from six dogs were evaluated for Helicobacter spp. by genus, gastric, and enterohepatic Helicobacter spp. Polymerase chain reaction, 16S rRNA gene sequence analysis, immunohistochemistry, and fluorescence in situ hybridization (FISH).
Results:  In the stomach, Helicobacter spp. DNA was detected in all six dogs, with H. bizzozeronii and H. felis identified by specific polymerase chain reaction. Helicobacter organisms were localized within the surface mucus, the lumen of gastric glands, and inside parietal cells. The small intestine harbored gastric and enterohepatic Helicobacter spp. DNA/antigen in low amounts. In the cecum and colon, Helicobacter spp. DNA, with highest similarity to H. bilis /flexispira taxon 8, H. cinaedi , and H. canis, was detected in all six dogs. Helicobacter organisms were localized at the mucosal surface and within the crypts. Gastric Helicobacter spp. DNA was detected occasionally in the large intestine, but no gastric Helicobacter spp. were present in clone libraries or detected by FISH.
Conclusions:  This study demonstrates that in addition to the stomach, the large intestine of dogs is also abundantly colonized by Helicobacter spp. Additional studies are necessary to investigate the association between enterohepatic Helicobacter spp. and presence of intestinal inflammatory or proliferative disorders in dogs.  相似文献   
62.
A study was conducted with non-conventional ingredients to test their efficacy as fishmeal (FM) replacers in the diet of fringe- lipped carp. Labeo fimbriatus first feeding larvae and fry were reared for 30 and 60 days in indoor, 50 L, aerated, circular plastic tanks at 100 and 30 numbers tank−1, respectively. In the first feeding larvae to fry rearing experiment (Exp. 1), the fish were fed with either of the following isonitrogenous and isocaloric diets – live plankton, FM diet, green bottle fly (Lucilia sericata) larvae meal (GBFLM) diet and silkworm pupa (SWP) diet. The fry to fingerling rearing (Exp. 2), was also conducted using the same diets described above except live plankton. All compounded diets were formulated to contain 40% crude protein for the experiment 1 and 35% for experiment 2 and were fed ad libitum. Triplicate tanks were maintained for each treatment in both the experiments. In Exp. 1, the mean final weight of fry was higher with plankton and FM diets, while no difference (p > .05) was observed between FM and GBFLM diets. Weight of fish fed SWP diets was not statistically different from those fed GBFLM diet. No difference (p > .05) in final length, survival and condition factor was recorded. Analysis of digestive enzyme activity of whole fish revealed lower (p < .05) activity of amylase in fish fed plankton. In Exp. 2, no difference (p > .05) was observed between the different diet groups in terms of mean final weight, length, survival and condition factor. Analysis of digestive enzyme activity of whole fish revealed no difference (p > .05) in the activity of digestive enzymes between the treatments except a lower (p < .05) activity of trypsin in FM diet and lipase in FM and GBFLM diets. Since the survival and condition factors of animals is the most important aspect during nursery rearing, similar (p > .05) values recorded in different treatments indicate the possibility of incorporation of these non-conventional protein sources in the diet of L. fimbriatus during first feeding larvae to fry and fry to fingerling rearing.  相似文献   
63.
64.
【目的】肠道是动物的主要消化器官,同时也是机体抵抗外源病原菌的重要屏障,已有研究表明,动物的品种、饲养方式、生长阶段均会影响动物的肠道菌群结构,但对舍饲和放牧饲养条件下藏猪的肠道菌群结构,以及藏猪和长白、约克与杜洛克三元杂交猪(DLY猪)的肠道菌群结构是否有差异,尚未见报道。【方法】本研究选取6–7月龄的放牧藏猪、舍饲藏猪和DLY猪的小肠组织,分别采用组织切片法测定各试验猪的肠道形态、酶活性测定试剂盒测定肠道内容物的消化酶活性,高通量测序法测定肠道微生物。【结果】DLY猪小肠的肌层厚度和绒毛高度高于藏猪,而隐窝深度低于藏猪;舍饲藏猪和放牧藏猪的小肠形态没有显著变化。DLY猪小肠的胰蛋白酶活性高于藏猪,而淀粉酶活性低于藏猪。三组猪小肠微生物的优势菌门均为Proteobacteria、Firmicutes和Bacteroidetes;藏猪的优势菌属为Ralstonia和Escherichia,而DLY猪的优势菌属为Ralstonia和Bradyrhizobium,但含量却存在显著性差异。舍饲藏猪与放牧藏猪肠道菌群结构相似度较高,而藏猪与DLY猪肠道菌群结构相似度较低。【结论】放牧藏猪、舍饲藏猪和DLY猪的小肠形态、消化酶活性和肠道菌群结构均存在显著性差异。  相似文献   
65.
目的探讨输尿管软镜协同输尿管硬镜治疗复杂上尿路结石的临床效果。方法选择我院收治的复杂上尿路结石患者96例,按入院顺序分为对照组和观察组,每组48例。对照组采取输尿管硬镜钬激光碎石术治疗,观察组采取输尿管软镜协同输尿管硬镜钬激光碎石术治疗。比较两组患者1次性碎石成功率、结石彻底清除率、炎症反应情况以及生活质量、住院时间、术后并发症发生率、疾病复发率。结果观察组患者的1次性碎石成功率、结石彻底清除率均高于对照组,两组比较差异有统计学意义(均P<0.05)。术后3 d,观察组的肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、C-反应蛋白(CRP)水平均较对照组降低,差异有统计学意义(均P<0.05)。术后1周,两组患者的生活质量比较,观察组的生活质量量表(SF-36)评分明显高于对照组,住院时间短于对照组,两组比较差异有统计学意义(均P<0.05)。两组患者的并发症发生率、疾病复发率比较,观察组均明显低于对照组,差异有统计学意义(均P<0.05)。结论输尿管软镜联合输尿管硬镜治疗复杂上尿路结石的效果满意,且创伤小,结石清除率高,不良反应低,具有一定临床应用价值。  相似文献   
66.
目的探讨早产儿肠道微生态变化及其与胎龄、出生体质量的关系。方法选取2018年5月至2020年5月我院收治的80例早产儿作为早产组,同期收治的80例足月新生儿作为对照组。收集入组新生儿出生后3 d、3周的粪便,比较2组研究对象粪便标本中细菌丰富度和Shannon Wiener指数;根据早产组胎龄和出生体质量不同分组,分析胎龄、出生体质量与肠道微生态变化的关系。结果(1)出生3 d,早产组新生儿粪便标本的DGGE图谱条带数、Shannon Wiener指数均显著低于对照组(t=3.179、3.521,均P<0.05);(2)出生3 d,胎龄34+1~36+6周组新生儿粪便标本的DGGE图谱条带数、Shannon Wiener指数显著高于28~30周组、30+1~32周组和32+1~34周组(q=9.653、6.476、4.848和8.796、8.008、6.277,均P<0.05);(3)出生3 d,体质量>2 000 g组新生儿粪便标本的的DGGE图谱条带数、Shannon Wiener指数显著高于≤1 500 g组(q=5.601和4.593,均P<0.05);(4)不同出生体质量、胎龄的早产儿,出生3周粪便标本的DGGE图谱条带数、Shannon Wiener指数相比差异无统计学意义(F=1.577和2.326,均P>0.05)。结论与足月新生儿相比,早产儿出生后细菌定植出现延迟且多样性差,胎龄越小、出生体质量越低的早产儿的肠道菌群的多样性更低、定植延迟的可能性更大,出生3周后其肠道微生态逐渐恢复正常。  相似文献   
67.
动物乳杆菌的分离鉴定及其抑菌蛋白的特性分析   总被引:2,自引:0,他引:2  
通过滤纸片法从健康肉猪猪大肠、小肠中分离得到212株抗生物质产生菌, 以杯碟法复筛, 得到1株对溶壁微球菌(Micrococcus lysodeikticus)、金黄色葡萄球菌(Staphylococcus aureus)、枯草芽孢杆菌(Bacillus subtilis)、蜡状芽孢杆菌(Bacillus cereus)等革兰氏阳性菌和大肠杆菌(Escherichia coli)、鼠伤寒沙门氏菌(Salmonella typhimurium)等革兰氏阴性菌以及部分真菌如禾谷镰刀霉(Fusarium graminearum)均有强烈抑制作用的乳酸菌。经形态学、生理生化特征及16S rDNA序列同源性分析等手段鉴定该菌株为动物乳杆菌(Lactobacillus animalis)。排除酸和过氧化氢的干扰后, 该菌株的发酵上清液对指示菌仍有明显抑菌活性; 用蛋白酶处理该菌株的发酵上清液后, 抑菌活性丧失; 发酵液粗提物具有较好的热稳定性(经121°C处理20 min仍有较强抑菌活性)以及较宽的抑菌活性pH值范围(3.5~5.5), 因此初步认为该菌株产生一类具有广谱抑菌活性的类细菌素物质。  相似文献   
68.
In contrast to mammals, teleost fish exhibit an enormous potential to regenerate adult spinal cord tissue after injury. However, the mechanisms mediating this ability are largely unknown. Here, we analyzed the major processes underlying structural and functional regeneration after amputation of the caudal portion of the spinal cord in Apteronotus leptorhynchus, a weakly electric teleost. After a transient wave of apoptotic cell death, cell proliferation started to increase 5 days after the lesion and persisted at high levels for at least 50 days. New cells differentiated into neurons, glia, and ependymal cells. Retrograde tract tracing revealed axonal re-growth and innervation of the regenerate. Functional regeneration was demonstrated by recovery of the amplitude of the electric organ discharge, a behavior generated by spinal motoneurons. Computer simulations indicated that the observed rates of apoptotic cell death and cell proliferation can adequately explain the re-growth of the spinal cord. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
69.
The effects of different sources of dietary fibre on gastrointestinal tract (GIT) development and digesta pH were studied in 25-day-old broilers. There were four diets: a control diet low in fibre content (37.3 g neutral detergent fibre and 16.0 g acid detergent fibre/kg) and three additional diets in which 30 g/kg of cellulose (CEL), sugar beet pulp (SBP) or oat hulls (OH) were included at the expenses of sepiolite (a complex magnesium silicate clay). The relative weight (RW, %BW) of the GIT was greater with the SBP – than with the CEL – and the control diets. Also, gizzard RW was higher with the diet containing OH than with the diet containing CEL or the control diets, with the SBP diet being intermediate (P≤0.001). Fibre inclusion modified the pH of the GIT (P≤0.05) but the effects depended on the type of fibre. Crop pH was higher and proventriculus pH lower with SBP than with the other diets. However, gizzard pH was reduced with SBP and OH but not with CEL (P≤0.05). The pH of the digesta of the duodenum was similar for all diets but that of the jejunum, Meckel's diverticulum and ileum increased with SBP and decreased with CEL inclusion (P≤0.05). We concluded that dietary fibre affects the development and pH value of the different segments of GIT and that the effects differ according to the physico-chemical characteristics of the source of fibre used.  相似文献   
70.
An experiment was conducted to evaluate the effects of differently fermentable carbohydrates on changes in bacterial populations in the ileum of growing pigs fed low-phosphorus (P) diets. Eight barrows (mean surgery BW 36 ± 0.9 kg) were fitted with simple T-cannulae at the distal ileum and were assigned to one of four dietary treatments: maize-soybean meal based control diet (CD), or 0.75 of CD supplemented with 0.25 lignocellulose, maize starch and high-methylated apple-pectin, respectively. Total bacterial cell counts as well as cell counts of Lactobacillus spp., Lactobacillus reuteri, Lactobacillus amylovorus/Lactobacillus sobrius, Lactobacillus mucosae, Enterococcus spp., Enterococcus faecium, Enterococcus faecalis, bifidobacteria, Clostridium coccoides cluster, Clostridium leptum cluster, Bacteroides–Prevotella–Porphyrmonas group and Enterobacteriaceae were determined by quantitative realtime PCR in DNA extracts of ileal digesta. Denaturing gradient gel electrophoresis (DGGE) of DNA fragments, generated by PCR targeting total or Lactobacillus spp. 16S rDNA, was used to estimate the bacterial diversity in the ileum. Lignocellulose supplementation tended (P<0.1) to increase cell counts of total bacteria in faeces compared with the control. Ileal bacterial populations responded differently to carbohydrate addition. Maize starch supplementation strongly stimulated the growth of total lactobacilli and Lactobacillus species (P≤0.05). Lignocellulose, in turn, enhanced the numbers of bifidobacteria, but reduced those of L. amylovorus compared with the control (P<0.05). Finally, pectin tended to increase the cell numbers of L. amylovorus/L. sobrius and the Bacteroides–Prevotella–Porphyrmonas group compared with the control (P<0.1). DGGE analysis revealed increased band numbers for total bacteria in the ileum of animals fed the lignocellulose and maize starch supplemented diets, while pectin reduced total bacterial (P<0.1) and Lactobacillus spp. diversity (P<0.05) compared with the control, as determined with the Shannon's index. Ileal VFA concentrations were decreased by pectin, while lignocellulose decreased faecal VFA concentrations. In conclusion, ileal bacterial populations and diversity are susceptible to changes in the carbohydrate composition of the diet. However, these changes were not related to major differences in the number of total bacteria in ileal digesta and faeces, but rather to changes in the bacterial species composition and their metabolic activity.  相似文献   
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