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61.
The Mexican lime industry is interested in developing lime cultivars with improved characteristics for fresh and processing markets. The objective of this study was to determine the field performance and genetic molecular differences among four new Mexican lime [Citrus aurantifolia (Christm) Swingle] clonal selections compared to traditional thorny Mexican lime under the dry tropical conditions of Mexico. Tree growth, production, fruit quality, and molecular markers of the traditional thorny Mexican lime (MLT) cultivar were compared to the following lime selections: thornless Mexican lime (MLTS), seedless Mexican lime (MLS), ML 12-8, and ML 20-3. After 10 years of evaluation MLS showed the highest and MLTS the lowest tree growth. Most of the genotypes covered the soil surface area assigned to tree growth since they were 7 years old. Only the less vigorous MLTS required 9 years to cover the same space. MLT was the most productive selection (165 kg/tree/year, mean of 8 years of evaluation). MLS was the less productive (81 kg/tree in the same period of time). MLTS, ML 12-8, and ML 20-3 produced intermediate yields. Acidity and total soluble solids among the selections were very similar. However, MLS had the higher juice content and the lower seed number. The MLS selection is attractive for export market due to these characteristics. AFLP studies confirmed genetic differences among the five lime selections. Nevertheless, all five selections shared many bands as expected.  相似文献   
62.
Prostatomegaly is a common finding in older non‐neutered dogs. This study compared the serum testosterone, sperm quality and characteristics of the prostatic fraction between healthy dogs and dogs with prostatomegaly. Blood samples of ten dogs (five dogs from each group) were taken for serum testosterone measurement. Sperm motility, vigour, concentration, viability, membrane functionality and morphology were analysed in sperm‐rich fraction. Osmolality, pH, cell types, and albumin, haemoglobin, acid phosphatase, alkaline phosphatase, glucose, triglycerides, cholesterol, calcium, phosphorus, magnesium and chloride were analysed in prostatic fraction. Dogs with prostatomegaly have the lowest sperm motility, vigour, concentration and functional membrane. Dogs with prostatomegaly have the highest glucose, triglycerides and cholesterol. Glucose was the only constituent positively correlated with serum testosterone and prostate volume. It can be concluded that dogs with prostatomegaly have poorer sperm quality, and glucose, triglycerides and cholesterol in prostatic fraction can be used as prostatomegaly biomarkers.  相似文献   
63.
In Chile, the species Choromytilus chorus stands out for its ecological and economic importance. This mussel has a very particular condition in the colour of the gonad, being cream‐yellow colour the male gonad and dark brown the female which is hardly desired by the consumers. In this context, the aim of this research is to determine the role that sex steroids have in gonadal differentiation of the mussel C. chorus. For this, juveniles with sizes 15–22 mm were selected, which were subjected to acute exposure in the form of bath for 60 days to four treatments: T1: dihydrotestosterone (DHT); T2: 17β‐estradiol (E2), T3: fadrozole (F) and T4: DHT‐F (DF), plus a control without chemicals. Each treatment as well as control included three replicates with 90 individuals each. The mussels undergoing treatment with E2 had a sex ratio (male:female) of 0.47 compared to 1:1 in the control group. In contrast, in the groups treated with DHT, F and DF the sex ratio changed to 2.0, 1.60 and 1.70 respectively. In the fertilization trials, all the mussels produced functional gametes, as they were able to generate gametes that were developed to morula, and veliger larva. Nevertheless, it should be noted that the size of oocytes from the group exposed to estradiol (61.12 ± 2.40 μm) was significantly higher than in other groups. These results support the hypothesis that sex steroids would be involved in sexual differentiation of marine bivalves.  相似文献   
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65.
Objective— To investigate neutrophil accumulation after ischemia and reperfusion (IR) in microvascular tissue flaps in horses.
Study Design— Randomized controlled experiment.
Sample Population— A total of 8 horses between 1 and 10 years of age, 4 of each sex.
Methods— Control and experimental myocutaneous island flaps based on the superficial branch of the deep circumflex iliac vessels were dissected on each horse. Atraumatic vascular clamps were applied to the pedicle of the experimental flap for 90 minutes and then removed to allow reperfusion. Based on the assumption that rapid infiltration of neutrophils into affected tissues is a hallmark of IR injury, radiolabeled autogenous leukocytes were used to indirectly quantify neutrophil accumulation in flap tissues. Labeled leukocytes were administered through a jugular catheter 30 minutes before flap reperfusion. Biopsies were collected from each flap over a 6 hour postischemia time period; in group 1 (  n = 4  ) from 0 to 6 hours postischemia, and in group 2 (  n = 4  ) from 24 to 30 hours postischemia. Biopsies were examined scintigraphically and histologically for evidence of neutrophil infiltration.
Results— All control flaps survived and 6 of 8 experimental flaps survived. There was no significant evidence of acute neutrophil infiltration into flap tissues after reperfusion in either group.
Conclusions— The results of this study suggest that equine myocutaneous flap tissues can survive a 90-minute ischemic period and reperfusion. No significant evidence of the occurrence of IR injury in flap tissues was found.
Clinical Relevance— The reasons for the previously reported failures of equine free tissue transfer remain uncertain, but they do not appear to be caused by neutrophil mediated injury associated with ischemia and reperfusion.  相似文献   
66.
Eight healthy mongrel dogs were treated with half-body irradiation (HBI) in a pilot study to evaluate the technique and radiotolerance of different organs. Cranial and caudal half-body fields were established using the 13th thoracic vertebra as the dividing point. Under general anesthesia, either 7 or 8 Gray (Gy) were delivered to one half of the body using opposing radiation portals. The other half of the body was similarly treated 28 days later. The dogs were monitored for 12 months. Significant radiation effects included transient bone marrow suppression and radiation sickness. There were no serious or life-threatening problems, but the 8 Gy group consistently showed more severe clinical signs and histologic changes than the 7 Gy group. Total body irradiation in two fractions of 7 or 8 Gy given 1 month apart appears to be a safe treatment that can be developed for therapy in veterinary oncology.  相似文献   
67.
Microneurovascular Free Digital Pad Transfer in the Dog   总被引:1,自引:0,他引:1  
By cadaver dissections, the fifth digit of the canine hind limb was determined to have a consistent neurovascular anatomy, and therefore be a suitable donor for an axial pattern digital pad flap. The defined digital pad flap was transferred to the region of an excised metacarpal pad by microneurovascular anastomoses in five operations on four dogs. One flap failure was considered to result from failure of the venous anastomosis. In all four successful transfers, cutaneous sensation was reestablished on average in 78 days. There was histologic evidence of nerve regeneration across the anastomosis in one dog at week 24. The transferred pads of three dogs monitored for 15 months underwent hypertrophic changes. There were no complications in two active dogs. In one dog, superficial ulceration of a region of the flap adjacent to the pad required surgical revision. This dog continued to show mild lameness after daily runs of 3 to 4 km.  相似文献   
68.
Hand sutured end-to-end (EE) and stapled side-to-side (SS) small intestinal anastomoses were performed in 10 healthy adult horses. In five SS anastomoses, staple lines on the blind ends of the jejunum were inverted (SSI) and in five they were not (SSNI). Five EE anastomoses were sutured with polydioxanone and five were sutured with polyglyconate. All horses were euthanatized on day 30. Intra-abdominal adhesions were graded (0-4), and stomal areas were calculated from contrast radiographs made with the bowel distended. Histopathology scores for the anastomoses were based on the degree of inflammation (0-3), fibrosis (0-3), and alignment and healing of intestinal layers (0-3). Mean surgery times +/- standard deviations for EE, SSI, and SSNI techniques were 33.9 +/- 5.4, 36.2 +/- 5.6, and 29.6 +/- 5.9 minutes, respectively. Mean and median stomal areas were 9.4 +/- 5.5 and 8.9 cm2 for EE anastomoses and 17.2 +/- 16.5 and 12.1 cm2 for SS anastomoses. Intra-abdominal adhesions developed in three horses, one of which had clinical signs of colic. Mean histopathology scores for EE and SS anastomoses were 4.8 +/- 2.0 (median = 5) and 4.4 +/- 1.8 (median = 4), respectively. There were no statistically significant differences in surgery times, intra-abdominal adhesion scores, stomal areas, or histopathology scores between small intestinal EE and SS anastomoses in these horses.  相似文献   
69.
70.
Albendazole (ABZ) biotransformation was studied in vitro in liver microsomes of adult noncastrated male farm animals (ram, buck, bull and boar), castrated adult males (wether, billy and hog), and free living males (fallow buck, red deer stag, mouflon ram, roe buck and wild boar). Liver microsomal fractions were incubated with either ABZ or racemic albendazole sulphoxide (ABZSO). ABZ was extensively metabolized to the (+) and (-) enantiomers of ABZSO, whereas ABZSO underwent a slow oxidation to albendazole sulphone (ABZSO2) in all species. In all species both ABZSO enantiomers were detected. The chiral ratio, (+)-ABZSO/(-)-ABZSO, was greater than one in farm animals, mouflon and wild boar, and less than one in three species of deer. For total ABZ sulphoxidation, deer like species had lower values compared to the other species. Mouflon ram and ram had lower total sulphoxidation rates compared to wethers, as well as ABZ suphoxidation towards (+)-ABZSO. No significant difference occurred comparing ABZSO formation in mouflon ram and ram, but ABZSO2 formation rate in mouflon ram was higher than in rams and wethers. Roe deer stag, fallow buck and red deer stag did not differ in both total-ABZSO and (-)-ABZSO synthesis rates and roe deer stag and fallow buck did not differ in synthesis rates of (+)-ABZSO and ABZSO2. The bull differed from other species in all metabolites studied, except for red deer stag and boar in (-)-ABZSO synthesis rate. The extent of ABZSO sulphonation to ABZSO2 in bull microsomes was more than twice that of other species.  相似文献   
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