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Duodenogastric reflux (DGR) has been implicated in several disease processes. The present study was carried out to document the incidence and evaluate the clinical significance of DGR after choledochoduodenostomy (CDD). A total of 13 patients who had undergone cholecystectomy with a standard side-to-side CDD for choledocholithiasis or chronic pancreatitis were studied by symptom evaluation, scintigraphy, endoscopy, and gastric mucosal histology at least 6 months after surgery. The scintigraphic findings were then compared with those of 10 patients who had undergone cholecystectomy alone. Only two patients (15%) had mild dyspeptic symptoms. The incidence of DGR after CDD was 69% compared to 20% in the cholecystectomy alone group (P < 0.05). In the majority of patients the DGR was only mild to moderate and the severity correlated well with the degree of endoscopic gastritis, but not with the clinical symptoms or histological findings. These results indicate that while CDD is associated with a high incidence of DGR, its occurrence does not produce significant clinical symptoms.  相似文献   
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The diversification of the rural population of the United States provides substantial challenges to the current and to future health care systems in rural areas. Because of a variety of historical, discriminatory, and other factors, minority populations have had lower levels of access to health care in rural as well as urban areas and higher rates of both mortality and morbidity than nonminority populations. Although minority health issues have often been seen as primarily urban issues, this article demonstrates that minority population growth has become a major component of total population growth in rural areas in the past several decades (accounting for nearly 62% of the net growth in the nonmetropolitan population of the United States in the 1980s and for nearly 42% in the 1990s), that future US population growth is likely to be largely a product of minority population growth (nearly 89% of US net population growth from 2000 to 2100 is projected to be due to minority population growth), and that the incidence of diseases and disorders in the US population will come to increasingly involve minority populations (by 2050 roughly 43% of all disease/disorder incidences would involve minority population members). The growth of younger minority populations with disproportionately impoverished socioeconomic characteristics will pose challenges for rural areas and health care systems, which also are likely to face health issues created by disproportionately older populations.  相似文献   
4.
Background and Objective: The shape of the treatment pulse of the diode laser (810 nm) can be easily altered electronically in contrast to ion laser photocoagulators. We investigated whether changes in laser pulse shape influenced the subjective pain response in patients undergoing retinal photocoagulation when only topical anesthesia was used. Study Design/Materials and Methods: Twenty consecutive patients required peripheral retinal photocoagulation for proliferative diabetic retinopathy or extensive retinal breaks. Three diode pulse waveforms including a square wave, shaped-wave, and an envelope of micropulses were compared to one another. Power was adjusted so that each waveform delivered the same total energy. The patients subjectively ranked the intensity of any pain they experienced for each group of lesions. Responses were compared to one another using an analysis of variance. Results: 40% of patients found the standard square wave pulse to be significantly more painful (P < 0.05) than the shaped pulse mode and 30% found the square wave significantly more painful (P < 0.05) than the micropulse mode. Conclusion: Modification of the laser pulse waveform may ameliorate pain induced by diode laser photocoagulation of the retinal periphery. © 1995 Wiley-Liss, Inc.  相似文献   
5.
Syncytia or multinucleated giant-cell formation is one of the major cytopathic effects induced by human immunodeficiency virus (HIV) infection. Cell fusion results from the strong interaction of CD4 molecules on the surface of the uninfected T cells and gp120, an external envelope glycoprotein of HIV on the infected T cells. We studied the production of HIV in fusion cells between MOLT-4 and virus-infected MOLT-4/HIV cells and found that HIV production was enhanced up to three- to fivefold, which showed a good correlation with the appearance and extent of syncytia formation. Blocking the fusion by monoclonal antibody against a binding epitope of CD4 molecule to gp120 decreased the HIV production significantly. Enhancement of HIV production was observed by more than five-fold in comparison with chronically infected cells, which were fusion free 20 hr postcocultivation. Electron microscopic observation also showed the presence of abundant HIV particles inside the fused cells and on the outer surface. AZT blocked the HIV augmentation of fused cells in coculture completely. Southern blot analysis revealed that both integrated and unintegrated HIV DNA were highly accumulated in fusion cells, as compared with fusion-free MOLT-4/HIV cells. Among unintegrated DNA, circular and linear DNA were accumulated to a similar degree. Northern blot hybridization showed that rapid enhancement of all three species of HIV-specific RNA containing genomic (9.2 kb) and subgenomic (4.3 and 1.9 kb) RNAs were found 20 hr postinfection in fusion cells. These data suggest that syncytia formation is an extremely active infection process of HIV, by which multiple rounds of reinfection might take place.  相似文献   
6.
Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues.  相似文献   
7.
Biotinylated dextran amine (BDA) was used to retrogradely label afferents innervating the utricular macula in adult pigeons. The pigeon utriclar macula consists of a large rectangular-shaped neuroepithelium with a dorsally curved anterior edge and an extended medioposterior tail. The macula could be demarcated into several regions based on cytoarchitectural differences. The striola occupied 30% of the macula and contained a large density of type I hair cells with fewer type II hair cells. Medial and lateral extrastriola zones were located outside the striola and contained only type II hair cells. A six- to eight-cell-wide band of type II hair cells existed near the center of the striola. The reversal line marked by the morphological polarization of hair cells coursed throughout the epithelium, near the peripheral margin, and through the center of the type II band. Calyx afferents innervated type I hair cells with calyceal terminals that contained between 2 and 15 receptor cells. Calyx afferents were located only in the striola region, exclusive of the type II band, had small total fiber innervation areas and low innervation densities. Dimorph afferents innervated both type I and type II hair cells with calyceal and bouton terminals and were primarily located in the striola region. Dimorph afferents had smaller calyceal terminals with few type I hair cells, extended fiber branches with bouton terminals and larger innervation areas. Bouton afferents innervated only type II hair cells in the extrastriola and type II band regions. Bouton afferents innervating the type II band had smaller terminal fields with fewer bouton terminals and smaller innervation areas than fibers located in the extrastriolar zones. Bouton afferents had the most bouton terminals on the longest fibers, the largest innervation areas with the highest innervation densities of all afferents. Among all afferents, smaller terminal innervation fields were observed in the striola and large fields were located in the extrastriola. The cellular organization and innervation patterns of the utricular maculae in birds appear to represent an organ in adaptive evolution, different from that observed for amphibians or mammals.  相似文献   
8.
The results of analysis of auditory brain- stem evoked responses (ABRS) are reported in 173 patients with delayed speech (DS). The mean age of the patients is 4.6 years (age ranges from 1.4 years to 10 years). The patients were classified into 5 groups based on ABR findings:
–  Group I (62 patients) had normal hearing threshold and peak- interpeak latencies. The mean amplitude of wave I was however, not significantly low (p < 0.03).
–  Group II (27 patients) had an increased hearing threshold (40 dB), mild delay in the mean absolute peak latency of wave I (p < 0.03), decreased I– IV interval (p < 0.03), but highly significant reduction of wave I amplitude (p < 0.004). There is also a significant latency delay (p < 0.001) and amplitude reduction (p < 0.05), when this wave is compared with that a Group I (as control). These observations are suggestive of mild degree of peripheral hearing deficit in this group.
–  Group III (49 patients) had gross ABR abnormalities of various nature and hence may be sub- grouped into (a) SNHL cochlear type (55%) (b) SNHL retrocochlear type (4%) and (c) severed degree of SNHL undecisive group (41%). Ten patients (2.7%) among the sub- group (a) had unilateral hearing loss and another 3 had Down’s syndrome.
–  Group IV (conductive deafness) had an increased hearing threshold and shifting of ABR waves towards right with normal I– V interval. Only 6 patients were found in this group. It may be that conductive deafness is less important as a cause.
–  Group V (29 patients) had no responses at repeated ABR studies even at higher intensity of 95 dB, the ABR studies of this group correlates with the clinical evaluation of profound deafness. The delayed speech development in 84 patients (from Groups III, IV and V) may be caused by severe degree of hearing deficit as indicated by marked ABR abnormalities. If the mild peripheral hearing loss in Group II is added to the above groups, ABRs could identify 64.6% of our patients with hearing deficit. Hence, ABR test is most reliable and sensitive diagnostic test in detecting hearing loss, a common cause of delayed speech development in children.
  相似文献   
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Purpose:To provide a retrospective analysis of lesions of the caruncle which have been very rarely reported in the literature.Methods:A retrospective review of all the caruncular lesions between January 2000 and January 2020 was done at a single tertiary eye care hospital. The lesions were classified as benign and malignant lesions. Clinicopathological correlation was done for the excised lesions.Results:A total of 87 caruncular lesions were included in the study. Males (59%) were affected more than females (41%). The mean age at presentation was 44 ± 20 years. The mean duration of complaint was 36 ± 62 months. A total of 36 patients underwent surgical excision whereas the rest opted for conservative management. Recurrence was noted in five patients. Fifteen different types of lesions were identified histopathologically. Benign lesions (78%) were far more common than malignant ones (22%). Epithelial inclusion cyst was the most common benign lesion and sebaceous gland carcinoma was the most common malignant lesion. Correct clinicopathological correlation was seen in 52.7% of the cases. Caruncular tuberculosis, oncocytoma, and basosquamous cell carcinoma were some of the rare lesions.Conclusion:Caruncular lesions are uncommon and very diverse, which makes clinical diagnosis challenging. Epithelial inclusion cyst and sebaceous gland carcinoma were the most common benign and malignant lesions respectively. Correct clinicopathological correlation was seen in more than half of the cases.  相似文献   
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