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331.
Individual assistant professors (a total of 2966 faculty) hired in science and engineering since 1990 at 14 United States universities were tracked from time of hire to time of departure by using publicly available catalogs and bulletins. Results of survival analysis showed that the chance that any given faculty member will be retained over time is less than 50%; the median time to departure is 10.9 years. Of all those who enter as assistant professors, 64.2% were promoted to associate professor at the same institution. Overall, men and women are retained and promoted at the same rate. In mathematics, however, faculty leave significantly earlier than other disciplines, and women leave significantly sooner than men, 4.45 years compared with 7.33 years.  相似文献   
332.
The detection and subspeciation of Campylobacter fetus subsp. venerealis (CFV) from veterinary samples is important for both clinical and economic reasons. Campylobacter fetus subsp. venerealis is the causative agent of bovine genital campylobacteriosis, a venereal disease that can lead to serious reproductive problems in cattle, and strict international regulations require animals and animal products to be CFV-free for trade. This study evaluated methods reported in the literature for CFV detection and reports the translation of an extensively tested CFV-specific polymerase chain reaction (PCR) primer set; including the VenSF/VenSR primers and a real-time, quantitative PCR (qPCR) platform using SYBR Green chemistry. Three methods of preputial sample preparation for direct qPCR were evaluated and a heat lysis DNA extraction method was shown to allow for CFV detection at the level of approximately one cell equivalent per reaction (or 1.0 × 103 CFU/mL) from prepuce. The optimized sample preparation and qPCR protocols were then used to evaluate 3 western Canadian bull cohorts, which included 377 bulls, for CFV. The qPCR assay detected 11 positive bulls for the CFV-specific parA gene target. DNA sequence data confirmed the identity of the amplified product and revealed that positive samples were comprised of 2 sequence types; one identical to previously reported CFV parA gene sequences and one with a 9% sequence divergence. These results add valuable information towards our understanding of an important CFV subspeciation target and offer a significantly improved format for an internationally recognized PCR test.  相似文献   
333.
The clinical and diagnostic features of 155 cats with urinary tract infection (UTI) and 186 controls with negative urine culture/s were characterized retrospectively (signalment, clinical signs, urinalysis, urine culture, concurrent diseases, lower urinary tract diagnostic/therapeutic procedures). Multivariable logistic regression was used to identify risk factors associated with UTI. Cats of all ages were affected by UTI with no sex/breed predisposition. Lower urinary tract signs were absent in 35.5% of cats with UTI. Pyuria and bacteriuria had sensitivities of 52.9% and 72.9%, and specificities of 85.5% and 67.7% for detection of UTI, respectively. Risk factors significantly associated with increased odds of UTI were urinary incontinence [odds ratio (OR) = 10.78, P = 0.0331], transurethral procedures (OR = 8.37, P <0.0001), urogenital surgery (OR = 6.03, P = 0.0385), gastrointestinal disease (OR = 2.62, P = 0.0331), decreased body weight (OR = 0.81, P = 0.0259) and decreased urine specific gravity (OR = 0.78, P = 0.0055). Whilst not independently significant, renal disease and lower urinary tract anatomic abnormalities improved statistical model performance and contributed to UTI.  相似文献   
334.
335.
This study describes biological hazards reported by veterinarians working in western Canada obtained through a self-administered mailed questionnaire. The potential occupational hazards included as biological hazards were zoonotic disease events, exposure to rabies, injuries due to bites and scratches, and allergies. Only 16.7% (136/812) of responding veterinarians reported the occurrence of a zoonosis or exposure to rabies in the past 5 years; the most commonly reported event was ringworm. Most bites and scratches (86%) described by 586 veterinarians involved encounters with cats; 81% of the resulting 163 infections were due to cat bites or scratches. Approximately 38% of participants reported developing an allergy during their career, with 41% of the affected individuals altering the way they practiced in response to their allergy.  相似文献   
336.
The purpose of this pilot study was to evaluate lymph node enhancement with an indirect magnetic resonance (MR) lymphography technique using 2 different contrast agents in the head and neck region of healthy dogs. Five dogs were imaged at various times after intradermal injection of gadoversetamide and Gadofluorine M (minimum of 1 week apart) in the right and left mandibular, temporal, and lateral neck regions. We observed consistent progressive enhancement with time in the mandibular, retropharyngeal, and superficial cervical lymph nodes. The node enhancement was comparable for both contrast agents. Contrast enhancement of the parotid lymph nodes was not seen. We conclude that this technique of indirect MR lymphography using either agent could be used to identify those lymph nodes at highest risk of metastatic disease in dogs with cancer, and to guide staging and treatment.  相似文献   
337.
Status of dairy cow management and fertility in smallholder farms in Malawi   总被引:1,自引:1,他引:0  
A review of the smallholder dairy production in Malawi was conducted using livestock annual reports and other literature that was supplemented with primary data from a baseline survey conducted in December 2009. Smallholder dairy farming in Malawi operates with support from institutions that facilitate access to initial stock and dairy production technologies. Most farmers (94%) keep the animals in pens where feed is provided throughout the year. Results indicated unsatisfactory feeding, housing and health management practices, which negatively impact cow fertility. Dairy population trends suggest low replacement rates, which could be associated to low cow fertility and inadequate management skills. There are challenges related to access to breeding and health services, which further contribute to low productivity. Low fertility is evidenced by low calving rates (22–61%) and long calving interval (405–549 days). Existence of programmes on farmer capacity building provides an opportunity for improved management skills and cow productivity. It is concluded that dairy cow management and fertility have challenges and opportunities that are influenced by the extent to which farmers have access to important services such as extension, health, breeding and finance.  相似文献   
338.
The purpose of this retrospective study was to identify factors associated with quill injury in dogs. A second objective was to determine the risk of complications and any factors that would predict the likelihood of complications. Hospital records of 296 porcupine quill injuries in dogs from 1998 to 2002 were studied. There was an increased occurrence of porcupine encounters in the spring and fall months; Siberian huskies, rottweilers, and German shepherd crosses were significantly overrepresented for quill injuries. There was no association between risk of complications and either number of quills or antimicrobial use. Increasing time between quill injury and presentation was associated with an increased risk of complications. Because of the increased frequency of complication with a longer interval until presentation, clients should be strongly encouraged to bring the dog in as soon as the quill injury is discovered. Patients presented after 24 hours should be monitored closely during the first 3 weeks after injury, as most complications occurred during this time.  相似文献   
339.
The purpose of this study was to describe clients' level of compliance with reminders that are computer generated and to identify factors associated with owner response to a recall. Client response to a recall notice revealed that clients responded to reminders for vaccination about 3 times less often than for the other recall codes combined (dental procedures, laboratory tests, medical progress examinations, and neutering). These results suggest that veterinarians need to move away from annual vaccination reminders and toward the promotion of preventive veterinary services, such as annual wellness examinations, screening laboratory testing, and routine dental procedures. Once a practice has committed to and set up the required computer systems to promote preventive veterinary care, the stage is set for the implementation and monitoring of recommendations and reminders. This type of practice philosophy and marketing coincides perfectly with an approach to maximizing compliance in all aspects of veterinary medicine.  相似文献   
340.
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