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31.
Background: Anterior segment findings in AIDS patients presenting with cytomegalovirus (CMV) retinitis have not been specifically addressed in the American literature. Methods: Our study evaluated 21 AIDS patients with CMV retinitis. Results: Nineteen (90%) of these patients exhibited corneal endothelial deposits concurrent with CMV retinitis. The endothelial deposits were microscopic, opaque, linear flecks arranged in a reticular-like fashion. Of 42 eyes evaluated, 32 (76%) demonstrated active CMV retinitis. Corneal endothelial deposits were noted in 26 (81%) of the 32 eyes with retinitis. These corneal endothelial deposits were absent in the eyes which did not have CMV retinitis. Conclusion: Meticulous examination of the retina of an HIV-positive or AIDS patient who presents with reticularly arranged, linear, flecked corneal endothelial deposits should be performed to ensure that the diagnosis of CMV retinitis can be ruled out.  相似文献   
32.
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   
33.
34.

Purpose

The literature describing the pulmonary mechanisms of increasedPA-PaO2 during general anaesthesia was examined to define the role of airway closure and sub-radiological atelectasis.

Source

A Medline search was designed to include articles dealing with the stated purpose, which is thus selective rather than a meta-analysis. The MeSH consisted of the following words: Anesthesia: general / inhalational; Pulmonary gas exchange; Ventilation.perfusion ratio; Lung Physiology; Lung Volume measurements; Closing Volume/Capacity; Functional Residual Capacity; Atelectasis; Diaphragm. Also, Dr H. Rothen and Prof. G. Hedenstierna supplied raw data.

Principal findings

Changes in shape and dimensions of the thorax and abdomen immediately after induction of anaesthesia result in marked alterations in the efficiency of oxygenation. Three pathways can be described: increased effects of airway closure, increased low ventilation: perfusion in dependent lung zones, and frank atelectasis. The magnitude of the alterations is determined by the patients’ age and body habitus. Some of the changes may carry-over into the postoperative period. The data suggest that increasing tidal volume during anaesthesia will reduce the effects of airway closure and that vital capacity breaths will re-expand atelectatic areas.

Conclusion

Airway closure and atelectasis contribute equally to the increased ventilation: perfusion mismatching that occurs during general anaesthesia.  相似文献   
35.

Purpose

This article examines and summarizes the published reports dealing with subcutaneous emphysema, pneumothorax and carbon dioxide (CO2) embolism during laparoscopic upper abdominal surgery. The purpose is to describe the expected clinical picture, the differential diagnosis and the management of these complications.

Source

The information was obtained from a Medline literature search and the annual meeting supplements of Anesthesiology, Anesth Analg, Br J Anaesth and Can J Anaesth.

Principal findings

An abrupt increase in PetCO2 is the first sign of subcutaneous emphysema and of pneumothorax. Desaturation and increased airway pressure occur with pneumothorax, but not with subcutaneous emphysema alone. Desaturation and increased airway pressure also occur with bronchial intubation. The preliminary diagnosis is made by verifying the position of the tube, examination of the patient for swelling and crepitus and auscultation for air entry. Chest radiography and paracentesis confirm the diagnosis of pneumothorax, which frequently occurs with subcutaneous emphysema but is rarely of the tension type. Pulmonary embolism due to CO2 during WAS has not been reported, but the available data suggest that small, haemodynamically inconsequential CO2 embolism occurs without change in PetCO2. Massive embolism is possible and will markedly decrease PetCO2, arterial O2 saturation (SpO2) and blood pressure.

Conclusion

The immediate recognition of the three complications requires continuous monitoring of PetCO2, arterial saturation, airway pressure, and an index of pulmonary compliance.  相似文献   
36.
1. Family planning occupied a subordinate position in the medical and health bureaucracy almost two decades after its introduction. Senior Ministry officials accorded low priority to formal program objectives, while the State Family Planning Officer, the highest state official concerned solely with the family planning program, suffered from a relatively subordinate position in the Directorate and a lack of authority and support. Within the medical profession, family planning was held in low esteem, and the medical and health bureaucracies did not have a mechanism for selecting personnel on the basis of interest and commitment. 2. Organizational adjustment to family planning in the Ministry of Health was a slow and painful process, absorbing the energy and attention of Ministry officials for almost a decade. The repeated reorganizations of the district setup revolving around the division of labor between medical, health, and family planning acitvities and between the rural and urban program, led to months of almost total inertia and detracted substantially from the supervisory capacity of the officials involved. 3. Decision making and guidance suffered from the quick turnover of the Secretary, the most powerful administrator in the Ministry. In Uttar Pradesh Secretaries stayed barely long enough to begin to understand the complex organizational setup of the program. 4. Multiple and often conflicting lines of authority characterized the relationships between the higher and lower echelons within the Ministry. This was accentuated when the District Family Planning Officer was placed under the administrative control of the District Magistrate. While intended to "energize" family planning through the association of the most prestigious and powerful district official with the program, this organizational arrangement resulted in conflicting instructions to the staffs of the primary health centers. 5. The organizational behavior of the Ministry of Health was shaped by the interplay of the various "professional cultures" of its key actors. The generalist administrators' short time horizon and eagerness to produce quantitative results clashed with the specialists' emphasis upon long-term goals and technical constraints; the politician's defense of the interest of his constituents clashed with the administrator's desire to defend his autonomy. The calculus of political survival made support for family planning goals a costly burden that few politicians have been willing to shoulder. As the party system does not reward the advocacy of family planning, ministers emphasize those programs within their ministry or those decisions within their discretion that correspond to the demands of their constituents.  相似文献   
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38.
Pediatric neoplasm is next only to trauma as the most common cause of death. The cervicofacial malignancies presents a unique challenge owing to potential adverse effects of both the disease process and the treatment employed on critical developing head and neck structures. This study comprised of 106 children below 12 years age group conducted during 1999–2003 at JNMC, Aligarh. Of 106 cases 70 were benign neoplasms and 36 malignant neoplasms. Nasopharynx was the commonest site of involvement. Nasopharyngeal angiofibroma was the commonest benign tumour and lymphoma was the commonest malignant neoplasm. Team approach is required for mitigation of the disease process.  相似文献   
39.
Our patient is a 3‐week‐old female neonate, presented with complaints of low‐grade fever and a congested nose for one day. Eventually, she developed progressive desaturation, hypotension, and poor perfusion due to severe pulmonary hemorrhage. Then, she developed cardiac arrest and was declared dead.  相似文献   
40.
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