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31.
Laparoscopic hernioplasty techniques have been developed in the recent years to avoid the recurrence of inguinal hernias and to spare the testicles for breeding purposes in stallions. However, there have been no previous comprehensive and systematic studies of the reproductive outcomes and prognoses for stallions after inguinal hernioplasty. Therefore, the objective of this study was to assess the possible effects of one of these techniques (standing laparoscopic peritoneal flap hernioplasty) on the sperm production and motility characteristics of six healthy stallions that received this procedure based on 1‐year follow‐ups. There were no significant differences in the measured sperm variables (assessments based on the DSO, MOT, PMOT, VSL, VCL and VAP) during 1‐year follow‐ups.  相似文献   
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The relative influence of thermal and quantum fluctuations on the proton transfer properties of the charged water complexes H5O2+ and H3O2- was investigated with the use of ab initio techniques. These small systems can be considered as prototypical representatives of strong and intermediate-strength hydrogen bonds. The shared proton in the strongly hydrogen bonded H5O2+ behaved in an essentially classical manner, whereas in the H3O2- low-barrier hydrogen bond, quantum zero-point motion played a crucial role even at room temperature. This behavior can be traced back to a small difference in the oxygen-oxygen separation and hence to the strength of the hydrogen bond.  相似文献   
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Genetic information is needed on maysin, a compound in maize, Zea mays L., silks that is antibiotic to corn earworm larvae, Helicoverpa (formerly Heliothis) zea (Boddie), to assist in the process of breeding for resistance to this pest. This study was initiated to elucidate the inheritance of maysin content in the silks of a cross between two maize inbreds (GT114 and GT119) having resistance to the corn earworm. Reversed phase high performance liquid chromatography (HPLC) procedures were used to quantify the maysin concentration of silks from individual plants in the parent, F1, F2, and first backcross generations of the cross GT114 × GT119. A model assuming dominance at a single locus for low maysin content which is expressed only when a dominant modifier is present was proposed to explain the segregation ratios obtained in the F2 and first back-crosses of GT114 × GT119. This model also provided a fit for maysin data previously generated from a cross between inbreds F6 and F44. Observations of selfed families in the backcross of GT114 × GT119 to the low maysin parent confirmed the two-locus model (one factor with dominance for low maysin expressed only when a modifier gene is also present) as a plausible explanation for inheritance of silk maysin in the cross. The process of selection for high maysin will be complicated somewhat by the presence of a gene which modifies the expression of dominance unless a method of easily identifying the gene, independent of maysin content, can be developed.  相似文献   
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An increasing number of laboratory tests are available for diagnosis of gastrointestinal tract diseases in dogs and cats. Use of these tests can lead to more accurate and rapid diagnoses. This review discusses laboratory tests, both new and old, and the role they currently play in the evaluation of animals presented with gastrointestinal problems. A minimum database helps assess the severity of the disorder, detect extra-gastrointestinal causes of problems and assists in formulating diagnostic and therapeutic plans.

Faecal examination remains one of the most important diagnostic procedures in the investigation of gastrointestinal problems. Zinc sulphate faecal flotation is an excellent routine screening technique for helminth and protozoal infections, including giardiasis. Rectal cytology can assist in the diagnosis of large bowel disorders. Interpretation of faecal immunodiagnostic tests is hampered by insufficient knowledge of test sensitivities and specificities. Routine faecal cultures are not warranted and faecal occult blood tests are rarely indicated.

Serum tests for gastric inflammation are now under development. The serum trypsin-like immunoreactivity test remains the gold standard technique for the diagnosis of exocrine pancreatic insufficiency. Breath hydrogen tests can be helpful in assessing the functional relevance of mild abnormalities in small-bowel biopsy specimens. Subnormal concentrations of serum cobalamin appear to be more specific indicators of gastrointestinal disease in cats than in dogs. Tests for small intestinal bacterial overgrowth remain controversial and assessment of gastrointestinal permeability has yet to prove its value in the diagnostic assessment of companion animals with gastrointestinal problems. Faecal alpha1-protease inhibitor (α1-PI) shows promise for the diagnosis of protein-losing enteropathy.  相似文献   
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To test whether undernutrition during foetal to pre‐pubertal life would have long lasting effects on testicular histology in adult male offspring, eleven adult Sprague–Dawley pregnant rats were divided into two groups: Control group, n = 4, fed ad libitum, during gestation and lactation (until 25 day post‐partum). Underfed group pregnant females (n = 7) were kept in cages where only dams had access to food (standard rat chow, 33.5% of ad libitum intake of Control group pregnant dams). After parturition, litters were adjusted to either 14 (Underfed group) or eight (Control group) pups. Mothers were weighed weekly. At 25 day of age pups were weaned, housed at four animals per cage, fed ad libitum and weighed weekly until euthanized at 100 day of age. Testes were processed for standard histology and morphometrical evaluation. At weaning, mother weight was lower in Underfedthan in Control group (mean ± SD): 214.1 ± 26.2 g vs 361.9 ± 33.1 g. Body weight at 100 days of age (254 ± 26.9 g vs 342.4 ± 10.2 g, p ≤ 0.001), testicular weight (1.29 ± 0.16 g vs 1.45 ± 0.13 g, p = 0.03), number of Sertoli cells per seminiferous tubule cross section (18.2 ± 1.2 vs 20.2 ± 1.3, p ≤ 0.01) and per testis (30.5 ± 4.2×106 vs 36.0 ± 5.4×106) were lower (p < 0.05) in Underfed than in Control group. This is the first report stating that foetal to pubertal subnutrition is accompanied by changes in testicular structure and lower Sertoli cell numbers in adult life, strongly suggesting lower daily sperm production.  相似文献   
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Glomerular filtration rate (GFR), an important parameter of renal function, is difficult to assess clinically. Serum creatinine and blood urea nitrogen measurements lack sensitivity, whereas radionuclide determination of GFR is not always available and requires postinjection patient isolation. GFR can be determined using computed tomography (CT), most commonly via Patlak plot analysis. Four adult cats, two adult dogs, and a foal underwent abdominal CT under general anesthesia for various diseases of the upper urinary tract. CT‐GFR was measured with a single‐slice dynamic acquisition and Patlak plot analysis. In five animals, the total CT‐GFR appeared to be below normal, corresponding with mild (two animals) and moderate (two animals) increases of serum creatinine in four. In the two animals with normal or increased CT‐GFR, serum creatinine was within the reference values. A significant negative logarithmic relationship was found between CT‐GFR and serum creatinine values (P=0.008; r2=0.75). No complications occurred during or following CT‐GFR. CT examination provided clinically relevant information in 3/5 patients with possible ureteral obstruction and in 3/3 patients with suspected ureteral calculi. Single‐slice dynamic CT‐GFR was practical and provided clinically useful information in this small series of patients undergoing CT of the upper urinary tract. There was a significant relationship between CT‐GFR and serum creatinine values, which supports the clinical potential of CT‐GFR and justifies further investigation of this technique.  相似文献   
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