Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
In patients with cerebrovascular disease, hypercarbia may cause redistribution of regional cerebral blood flow from marginally perfused to well-perfused regions (intracerebral steal), as evidenced by regional cerebral blood flow studies during carotid endarterectomy. During hypothermic cardiopulmonary bypass, the pH-stat method of acid-base management produces relative hypercarbia. To determine whether pH-stat management produces relative hypercarbia. To determine whether pH-stat management induces intracerebral steals, we investigated nine patients with cerebrovascular disease undergoing coronary artery bypass grafting. During hypothermic cardiopulmonary bypass, arterial carbon dioxide tension was varied in random order between 40 mm Hg and 60 mm Hg (uncorrected for body temperature). Regional cerebral blood flow was measured by clearance of 133 xenon injected into the arterial inflow cannula. Nasopharyngeal temperature (26.8 degrees-28.0 degrees +/- 2.2 degrees-3.0 degrees C), perfusion flow rate (2.14-2.18 +/- 0.70-0.73 L/min/m2), mean arterial pressure (67-68 +/- 6-9 mm Hg), arterial carbon dioxide tension (302-308 +/- 109-113 mm Hg), and hematocrit (23% +/- 4%) were maintained within narrow limits in each patient during arterial carbon dioxide tension manipulation. Global mean cerebral blood flow values were similar to previously reported values in patients free of cerebrovascular disease; patients in this study averaged 15.2 +/- 2.5 ml/100 gm/min at an arterial carbon dioxide tension of 46.1 +/- 8.4 mm Hg and 25.3 +/- 6.1 ml/100 gm/min at an arterial carbon dioxide tension of 71.1 +/- 11.8 mm Hg. Carbon dioxide reactivity, defined as mean global cerebral blood flow (in ml/100 gm/min) divided by arterial carbon dioxide tension (in mm Hg), was similar in the region having the lowest regional cerebral blood flow and in the brain as a whole. No patient developed evidence of an intracerebral steal at the higher arterial carbon dioxide tension. During hypothermic cardiopulmonary bypass, higher levels of arterial carbon dioxide tension, such as those associated with the pH-stat management technique, are apparently not associated with potentially harmful redistribution of cerebral blood flow in patients with cerebrovascular disease. 相似文献
Background: Microemboli occur commonly during cardiac surgery in adults, and, when present, increase the risk of neuropsychological deficits. Their incidence and significance during correction of congenital heart disease is unknown. The authors hypothesized that microemboli would occur before bypass with right-to-left cardiac shunts and would also occur in large numbers when the aortic crossclamp was released in children during repair of congenital heart defects.
Methods: In 25 children studied with carotid artery Doppler, embolic signals were counted and timed in relation to 13 intraoperative events. Patients were classified as either at high risk (obligate right-to-left shunt or uncorrected transposition of the great arteries) or at low risk (net left-to-right shunt or simple obstructive lesions) for paradoxical (venous to arterial) emboli.
Results: The median number of emboli detected was 122 (range, 2-2,664). Forty-two percent of all emboli were detected within 3 min of release of the aortic crossclamp. The high-risk group had significantly more emboli (median, 66; range, 0-116) during the time interval before cardiopulmonary bypass than did the low-risk group (median, 8; range, 0-73), with P < 0.01. There was no significant difference between the high-and low-risk groups in the total number of emboli detected. There was no apparent association between number of emboli and gross neurologic deficits. 相似文献
Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous. 相似文献
The construction of a horizontal temperature gradient is described in detail. The apparatus is built from readily available and inexpensive materials. The chamber is built from PVC tubing, fitted with an aluminum floor, and placed in a sound-attenuated box. A temperature gradient is formed by placing solid CO2 at one end and a hot plate at the opposite end of an aluminum floor. The apparatus described is reliable, dependable, and has proven to be very suitable for use with small rodents. 相似文献
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method. 相似文献