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101.
We studied reflection of artificially induced and amplifi ed food motivation in impulse activity of the masticatory muscles during electrostimulation of “hunger center” of the lateral hypothalamus in the absence and presence of food. The threshold stimulation of the lateral hypothalamus in hungry and satiated animals in the absence of food induced incessant food-procuring behavior paralleled by regular generation of spike bursts in masticatory muscles with biomodal distributions of intervals between pulses. This reaction of masticatory muscles during stimulation of the lateral hypothalamus in the absence of food was an example of the anticipatory reaction reflecting characteristics of the action result acceptor. Higher level of hunger motivation during threshold stimulation of the lateral hypothalamus in hungry and satiated rabbits in the course of effective food-procuring behavior increased the incidence of spike burst generation during the food capture phase, but did not modify this parameter during the chewing phase. Impulse activity of the masticatory muscles reflected convergent interactions of food motivation and support excitation on neurons of the central generator of chewing pattern.  相似文献   
102.
慢性疼痛综合征患者常应用非甾体抗炎药( non-steroidal anti-inflammatory drugs,NSAID).许多这类患者有潜在的高血压和冠状动脉疾病.临床试验和系统性分析显示,选择性环氧化酶2抑制剂增加心肌梗死的风险[J].该发现可能导致更普遍地应用非选择性NSAID作为治疗慢性疼痛综合征的替代手...  相似文献   
103.
We developed a method for evaluation of dynamic changes in the level of food motivation in rabbits during successful food-procuring behavior. Quantitative and temporal parameters of food consumption over each successive cycle of food-procuring behavior were used. The amount of consumed food was converted into electrical signal using an electronic balance incorporated into a hardware-software complex. Temporal parameters of food-procuring activity were determined by changes in electric signal in real-time mode. This method makes it possible to record simultaneously food-procuring activity and impulse activity of masticator muscles and esophageal muscles, which enables parallel analysis of rhythms of food consumption, mastication, and swallowing.  相似文献   
104.

Background and Purpose

The Ca2+-permeable cation channel TRPV4 is activated by mechanical disturbance of the cell membrane and is implicated in mechanical hyperalgesia. Nerve growth factor (NGF) is increased during inflammation and causes mechanical hyperalgesia. 4α-phorbol 12,13-didecanoate (4αPDD) has been described as a selective TRPV4 agonist. We investigated NGF-induced hyperalgesia in TRPV4 wild-type (+/+) and knockout (–/–) mice, and the increases in [Ca2+]i produced by 4αPDD in cultured mouse dorsal root ganglia neurons following exposure to NGF.

Experimental Approach

Withdrawal thresholds to heat, von Frey hairs and pressure were measured in mice before and after systemic administration of NGF. Changes in intracellular Ca2+ concentration were measured by ratiometric imaging with Fura-2 in cultured DRG and trigeminal ganglia (TG) neurons during perfusion of TRPV4 agonists.

Key Results

Administration of NGF caused a significant sensitization to heat and von Frey stimuli in TRPV4 +/+ and –/– mice, but only TRPV4 +/+ mice showed sensitization to noxious pressure. 4αPDD stimulated a dose-dependent increase in [Ca2+]i in neurons from +/+ and –/– mice, with the proportion of responding neurons and magnitude of increase unaffected by the genotype. In contrast, the selective TRPV4 agonist GSK1016790A failed to stimulate an increase in intracellular Ca2+ in cultured neurons. Responses to 4αPDD were unaffected by pretreatment with NGF.

Conclusions and Implications

TRPV4 contributes to mechanosensation in vivo, but there is little evidence for functional TRPV4 in cultured DRG and TG neurons. We conclude that 4αPDD activates these neurons independently of TRPV4, so it is not appropriate to refer to 4αPDD as a selective TRPV4 agonist.  相似文献   
105.

Introduction

Paradoxically, a breast cancer risk reduction with conjugated equine estrogens (CEE) and a risk elevation with CEE plus medroxyprogesterone acetate (CEE + MPA) were observed in the Women’s Health Initiative (WHI) randomized controlled trials. The effects of hormone therapy on serum sex hormone levels, and on the association between baseline sex hormones and disease risk, may help explain these divergent breast cancer findings.

Methods

Serum sex hormone concentrations were measured for 348 breast cancer cases in the CEE + MPA trial and for 235 cases in the CEE trial along with corresponding pair-matched controls, nested within the WHI trials of healthy postmenopausal women. Association and mediation analyses, to examine the extent to which sex hormone levels and changes can explain the breast cancer findings, were conducted using logistic regression.

Results

Following CEE treatment, breast cancer risk was associated with higher concentrations of baseline serum estrogens, and with lower concentrations of sex hormone binding globulin. However, following CEE + MPA, there was no association of breast cancer risk with baseline sex hormone levels. The sex hormone changes from baseline to year 1 provided an explanation for much of the reduced breast cancer risk with CEE. Specifically, the treatment odds ratio (95% confidence interval) increased from 0.71 (0.43, 1.15) to 0.92 (0.41, 2.09) when the year 1 measures were included in the logistic regression analysis. In comparison, the CEE + MPA odds ratio was essentially unchanged when these year 1 measures were included.

Conclusions

Breast cancer risk remains low following CEE use among women having favorable baseline sex hormone profiles, but CEE + MPA evidently produces a breast cancer risk for all women similar to that for women having an unfavorable baseline sex hormone profile. These patterns could reflect breast ductal epithelial cell stimulation by CEE + MPA that is substantially avoided with CEE, in conjunction with relatively more favorable effects of either regimen following a sustained period of estrogen deprivation. These findings may have implications for other hormone therapy formulations and routes of delivery.

Trial registration

clinicaltrials.gov identifier: NCT00000611.  相似文献   
106.

Background

Hydrocele is abnormal collection of serous fluid in the tunica vaginalis or a patent processus vaginalis. It is commonly encountered in our practice and often requires surgical treatment. However in our setting and in many underdeveloped countries, availability of general anaesthetic service is poor due to lack of trained personnel and equipment.

Objectives

To ascertain the practicability and acceptability of hydrocelectomy under sedation and local anaesthesia in Nigerian adults with hydrocele

Patients and Methods

A prospective study was carried out over a two year period on patients that had hydrocelectomy at the surgery unit of the Obafemi Awolowo University Teaching Hospitals Complex, Wesley Guild Hospital, Ilesa. Consecutive patients with diagnosis of hydrocele who consented had hydrocelectomy using intramuscular diazepam sedation and spermatic-cord block with 0.5% plane xylocaine and the scrotum infiltrated with same along the line of incision.

Results

Fifty adult patients were studied: age range 15–94 years. Eighty percent of the patients had unilateral hydrocele and the commonest type was vaginal hydrocele (94%). All patients had hydrocelectomy, 96% were under local anaesthesia while 4% were converted to general anaesthesia. All patients except one prefer to have future surgery under such local anaesthesia and sedation.

Conclusion

Hydrocelectomy under local anaesthesia and sedation is practicable and was tolerated and accepted by the adults patients studied.  相似文献   
107.
108.
We present the case of a 19-year-old individual presenting to an orthopaedic outpatient clinic several months following a dashboard knee injury during a road traffic accident with intermittent mechanical symptoms. Despite unremarkable examination findings and normal magnetic resonance imaging, the patient was identified subsequently as having an intra-articular plastic foreign body consistent with a piece of dashboard on arthroscopic knee assessment, the retrieval of which resulted in a complete resolution of symptoms.  相似文献   
109.
BackgroundIntestinal parasitic infections (IPIs) are regarded as one of the main public health problems and socio-economic issues adversely affecting the health of millions of people worldwide. Our study aimed to describe the knowledge, attitude, and practices of local urban schoolchildren in Taiz City towards intestinal parasitic infections.Methods and materialThis is a cross-sectional study conducted in Taiz, Yemen from March to May 2019. A total of 385 schoolchildren were selected using a random sampling technique from 7 primary schools. Wet-mount microscopic examination, formol-ether concentration techniques, and Lugols'' iodine were employed in parasite detection and cyst identification.ResultsOf the 385 schoolchildren examined for IPIs, 107 (27.8%) were positive for the presence of enteric parasites, some having multiple infections. The prevalence was slightly higher in males 46 (28.6%) than in females 61 (27.2%) but have no statistical difference (P = 0.77). Entamoeba histolytica/dispar was the most common infection with 16.4% of cases. A substantial percentage (40.5%) of the respondents displayed poor knowledge. The respondents also revealed inappropriate attitudes and practices that contribute to the prevalence of IPIs in the study.ConclusionsThe study revealed the prevalence of intestinal parasites among the schoolchildren in Taiz, Yemen, suggesting that IPIs remain a major public health problem. Entamoeba histolytica/dispar was the most prevalent intestinal parasites identified among the schoolchildren. Age, poor knowledge of the mode of transmission, prevention, and acquisition of IPIs, and poor habitual hygiene practices increase the risk of acquiring intestinal infections.  相似文献   
110.

Purpose

We compared renal function outcomes among patients in the surveillance and intervention arms of the DISSRM registry.

Materials and methods

Patients were grouped into chronic kidney disease stages by estimated glomerular filtration rate range. Cases were considered up staged if a more advanced chronic kidney disease stage was entered during followup. Chronic kidney disease up staging-free survival was compared among groups using Kaplan-Meier analysis and paired comparisons log rank tests. Multivariate Cox regression identified independent predictors of chronic kidney disease up staging-free survival.

Results

A total of 162 patients met the study inclusion criteria, with 68 in the surveillance arm, 65 undergoing partial nephrectomy, 15 undergoing radical nephrectomy, and 14 undergoing cryoablation. Median tumor size was 2.2 cm. Mean estimated glomerular filtration rate change was significantly larger for radical nephrectomy vs. surveillance (?9.2 vs. ?0.5 ml/min/1.73 m2) and for radical vs. partial nephrectomy (?9.2 vs. ?1.9 ml/min/1.73 m2) (P = 0.001). No other groups differed significantly. On Kaplan-Meier analysis, patients undergoing radical nephrectomy had significantly worse chronic kidney disease up staging-free survival vs. those treated with partial nephrectomy (P = 0.029), surveillance (P = 0.007), and cryoablation (P = 0.019). No other groups differed significantly. On multivariate analysis, radical nephrectomy independently predicted poor chronic kidney disease up staging-free survival (odds ratio vs. surveillance 30.6, P = 0.001). Neither partial nephrectomy (P = 0.985) nor cryoablation (P = 0.976) predicted poor chronic kidney disease up staging-free survival relative to surveillance.

Conclusions

Patients in the surveillance arm had superior estimated glomerular filtration rate preservation compared to those in the radical nephrectomy but not the partial nephrectomy arm. In certain patients with small renal masses, surveillance and partial nephrectomy may offer comparable renal functional outcomes. This could be partly attributable to a modest estimated glomerular filtration rate decrease associated with surveillance itself. A thorough understanding of the renal functional impacts of treatment modalities is critical in the management of small renal masses.  相似文献   
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