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1.
Geraniol dehydrogenase, the specific enzyme involved in geraniol to citral TRANS (geranial) transformation, activity was monitored in various lemongrass cultivars differing in amounts and relative percentages of citral and geraniol in their essential oils. The enzyme activity had a positive and significant association with citral to geraniol, and geranial to geraniol ratios. The results are suggestive of a strong relationship between the enzyme activity and essential oil quality in lemongrass cultivars.  相似文献   
2.
An efflux pump inhibitor, SK-20 (5-(3,4-methylenedioxyphenyle)-4 ethyl-2E,4E-pentadienoic acid piperidide), was assessed for its toxicity at three different pharmacological profiles: acute, sub-acute and general pharmacology with pharmacokinetics. In acute study, the SK-20 was found safe up to a dose of 2000 mg/kg (b.wt.); and at sub-acute, dosages of 50 and 100 mg/kg (b.wt.) were found to be safe. However, dosages of 200 mg or above per kg (b.wt.) showed some morphological alterations in cellular architecture of both liver and kidneys in both sexes, viz., mild vascular congestion along with sporadic hemorrhages and infiltration into renal and hepatic parenchyma by mononucleate cell. General pharmacological studies did not result into any alterations in analgesic, convulsions, rectal temperatures and in the rhythm or the rate of the intestinal motility or the secretion of the bile. While the respiratory and the cardiac rate remained normal, the only parameter to show was the blood pressure, which at all the doses tested, showed a tendency toward reduction. Characteristically, the SK-20 at all doses influenced pentobarbital-induced hypnosis positively and negatively to spontaneous motor activity in a dose dependent manner. Pharmacokinetics of SK-20 revealed it to have retention time at 10.2 min and half life 2.47 h.  相似文献   
3.
The internal anal sphincter, the smooth muscle component of the anal sphincter complex, has an ambiguous role in maintaining anal continence. Despite its significant contribution to resting anal canal pressures, even total division of the internal anal sphincter in surgery for anal fistulas may fail to compromise continence in otherwise healthy subjects. However, recently reported abnormalities of the innervation and reflex response of the internal anal sphincter in patients with fecal incontinence indicate its significance in maintaining continence. The advent of sphincter-saving surgery and restorative proctocolectomy has re-emphasized the major contribution of the internal anal sphincter to resting pressure and its significance in preventing fecal leakage. The variable effect of rectal excision on rectoanal inhibitory reflex has led to a reappraisal of the significance of this reflex in discrimination of rectal contents and its impact on anal continence. Electromyographic, manometric, and ultrasonographic evaluation of the internal anal sphincter has provided new insights into its pathophysiology. This article reviews advances in our understanding of internal anal sphincter physiology in health and disease.  相似文献   
4.
PURPOSE: The significance of manometric anal waves is uncertain, and their fate and diagnostic importance are unknown. It is conceivable that in neurogenic fecal incontinence (NFI) the frequency and amplitude of these waves may be altered into specific, recognizable patterns. Evaluation of this unexplored relationship between fecal incontinence and anal manometric waves has potential diagnostic use. METHODS: Anal motility was studied in 20 patients, each with NFI and traumatic fecal incontinence (TFI), and results were compared with findings in 20 control subjects to determine changes in frequency and amplitude of anal waves in fecal incontinence. RESULTS: Frequency of slow waves when present (NFI=9.5/minute; TFI=9.5/minute; control subjects=9.1/minute) was identical in the three groups (P>0.05). Amplitude of slow waves (NFI=mean, 4.3 mmHg; TFI=mean, 3.9 mmHg; control subjects =mean, 6.6 mmHg) was reduced in patients who were incontinent compared with control subjects but failed to reach statistical significance (P>0.05). Frequency of ultraslow waves when present (NFI=mean, 0.75/minute; TFI =mean, 0.6/minute; control subjects=mean, 1.2/minute) was not statistically different between the three groups (P>0.05). Amplitude of ultraslow waves (NFI=mean, 10.5 mmHg; TFI=mean, 23.4 mmHg; control subjects=mean, 29.6 mmHg) was significantly reduced in NFI vs.control subjects (P<0.01) and between TFI vs.control subjects (P<0.05). CONCLUSIONS: Manometric slow and ultraslow waves, when present, retain their frequency characteristics, irrespective of underlying disease. Amplitude of slow waves was not statistically different from control subjects, but the amplitude of ultraslow waves was significantly decreased in patients who were incontinent.  相似文献   
5.
A 23-year-old man presented with congestion, peripheral corneal vascularization, an elevated ridge-like epithelial line and cellular infiltration around limbal transplants, 15 months after undergoing living-related simple limbal epithelial transplantation (SLET) for total limbal stem cell deficiency. A diagnosis of acute allograft rejection was made and he was treated with intravenous methylprednisolone, topical and oral prednisolone as well as systemic cyclosporine and azathioprine, leading to reversal of the signs. Similar findings were noted during a later rejection episode. An epithelial rejection line and cellular infiltration of limbal transplants are easily identifiable clinical signs of allograft rejection post SLET.  相似文献   
6.
Limb salvage surgery for malignant tumours of proximal humerus is an operative challenge, where the surgeon has to preserve elbow and hand functions and retain shoulder stability with as much function as possible. We treated 14 consecutive patients with primary malignant or isolated metastasis of proximal humerus with surgical resection and reconstruction by nail cement spacer. There were 8 females and 6 males, with a mean age of 28.92 years (range 16–51 years) and a mean follow-up of 30.14 months (range 12–52 months). The diagnosis was osteosarcoma in 8 patients, chondrosarcoma in 4 patients and metastasis from thyroid and breast carcinoma in 1 patient each. One of our patients had radial nerve neuropraxia, 1 developed inferior subluxation and 3 developed distant metastasis. Two patients died of disease and one developed local recurrence leading to forequarter amputation, leaving a total of 11 patients with functional extremities for assessment at the time of final follow-up which was done using the Musculoskeletal Tumour Society (MSTS) score. Though we were able to preserve the elbow, wrist and hand functions in all patients, the abductor mechanism, deltoid muscle and axillary nerve were not salvageable in any of cases. The mean MSTS score at the time of final follow-up was 19.09. Thus, proximal humeral reconstruction using nail cement spacer is a technical simple, cost-effective and reproducible procedure which makes it a reliable option in subset of patients where the functions around the shoulder cannot be preserved despite costlier prosthesis.  相似文献   
7.
Purpose:To report the clinical outcomes and histopathological and immunohistochemistry (IHC) features in eyes with the sequelae stage of vernal keratoconjunctivitis (VKC).Methods:Investigative study of corneal samples obtained following surgical intervention for vision restoration in four eyes of three patients with VKC. Patient 1 (an 11-year-old boy) had deep anterior lamellar keratoplasty in both eyes, Patient 2 (a 24-year-old male) underwent superficial keratectomy followed by penetrating keratoplasty, and Patient 3 (a 22-year-old male) underwent penetrating keratoplasty. The corneal samples retrieved after surgical intervention were assessed for histology features and immunohistochemistry (IHC) studies.Results:The grafts were clear till the follow-up of 2–18 months. Histopathology of all four corneal samples showed epithelial hyperplasia, absent Bowman layer, thick hyalinized stromal lamellae, vascularization, and chronic inflammatory cells such as lymphocytes and plasma cells. IHC showed strong expression of CK 3 in both eyes of Patient 1 and no expression in Patients 2 and 3. The marker for limbal stem cells, ABCG2, was absent in all four samples; however, p63α was expressed strongly in Patients 2 and 3, moderately in the right eye of Patient 1, and marginally expressed in the left eye of Patient 1.Conclusion:The eyes in the sequelae stage of VKC (having corneal scarring and 360° hypertrophied limbus) can be managed favorably with keratoplasty and amniotic membrane transplantation without allogenic/cadaveric stem cell transplantation. The expression of transient progenitor cells in the scarred corneas of VKC patients in the sequelae stage suggests that the limbal stem cell dysfunction is more likely partial and self-renewal of limbal stem cells is a plausibility in these eyes.  相似文献   
8.
Background A vesical calculus in a prolapsed cystocele is rare. Objective To highlight bladder calculi as a cause of irreducible uterine prolapse. Case Report A case of irreducible total uterine prolapse caused by multiple vesical calculi is presented. Bladder stones were removed through vaginal cystolithotomy followed by vaginal hysterectomy. Conclusion In cases of acute irreducible pelvic organ prolapse, the possibility of bladder stones should be kept in mind and X-ray pelvis including the prolapsed mass should be done to confirm the diagnosis.  相似文献   
9.
Outcome of corneal transplant rejection: a 10-year study   总被引:2,自引:0,他引:2  
PURPOSE: To study the incidence of graft rejection and the predictive factors for its reversibility. METHODS: It is a retrospective study of 1927 consecutive penetrating keratoplasties performed between January 1990 and January 2000 with more than 6 months follow up. A total of 224 rejection episodes were noted in 183 patients. Of these, 184 first rejection episodes were included in this study. RESULTS: The incidence of first rejection episode was 9.55%. Of patients 87% were symptomatic during the episode with vision loss being the commonest. The average time of onset of rejection was 15.25 +/- 14.4 months (median 11.7 months). In total, 53.3% of rejections occurred within 1 year after surgery. Of the patients who completed minimum 3 months follow up after the rejection episode, the rate of reversibility was 63.3%. Major predictive factors for a poor outcome after rejection were repeated grafting and associated anterior vitrectomy during surgery. The reversibility of the episode did not differ significantly with the modality of treatment used, but treatment with intravenous steroids within 7 days of onset of rejection may have a role in reducing the recurrences of rejection episodes, thus increasing the graft survival. CONCLUSION: Regrafts and associated anterior vitrectomy were significant risk factors for a poor outcome following rejection episode.  相似文献   
10.
For metered dose inhalers (MDIs), high-flow cascade impaction with a United States Pharmacopia (USP) throat provides a useful prediction of in vivo lung and oropharyngeal aerosol deposition. Particles expected to deposit in the lung are included in the "fine particle fraction" measured on the bench. Comparable in vitro standards are not available for nebulizers. The present study compared aerosol deposition in an in vitro model using low-flow cascade impaction with deposition in vivo in human subjects. A low-flow (1 Lmin), 10-stage cascade impactor measured aerodynamic distributions of aerosolized interferon-gamma (IFN-gamma) from two nebulizers (Misty-Neb and AeroEclipse). (99m)Technetium diethylene triaminepenta-acetic acid ((99m)Tc-DTPA) was used as the radiolabel. Two bench conditions were specified: no breathing (standing cloud) and simulated ventilation with a piston pump (tidal volume 750 mL frequency 25 per minute and duty cycle 0.5). Mass median aerodynamic diameter (MMAD) for both nebulizers was affected by ventilation (Misty-Neb vs. AeroEclipse: 5.2 vs. 4.6 microm for standing cloud and 3.1 vs. 2.2 microm during ventilation). In three subjects, measured values of oropharyngeal deposition averaged 68.1 +/- 0.08% for Misty-Neb and 30.9 +/- 0.03% for AeroEclipse. In vivo deposition patterns compared to aerosol distributions from both nebulizers indicated that, for wet nebulization, penetration of aerosol beyond the upper airways (fine particle fraction) will occur only for aerosol particles below 2.5 microm. This assessment requires that the bench aerosol distribution be measured under conditions of clinical use (i.e., during tidal breathing).  相似文献   
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