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991.
Letters   总被引:6,自引:0,他引:6  
  相似文献   
992.
The object of this study was to examine the effect of porcine follicular fluid (PFF) alone or in combination with estradiol (E2) on pulsatile LH release during the interval between the mornings of diestrus 2 (D2) and proestrus in the rat. Steroids were removed from PFF by charcoal extraction. Preliminary studies indicated that 1 ml PFF given intraperitoneally suppressed FSH secretion for up to 15 h, with an onset of action between 3 and 4 h and maximal suppression between 6 and 9 h. In subsequent experiments, six groups of animals were bled continuously for 3 h between 07.30 and 10.30 h at a rate of 50 microliter whole blood/5 min: group 1 was bled on D2; group 2 was sham ovariectomized on D2 (08.30-09.30 h), immediately implanted with an empty capsule, given saline at 12.00 and 24.00 h, and bled on proestrous AM; groups 3-6 were ovariectomized on D2, implanted with an empty or E2 capsule, given 1 ml saline or PFF at 12.00 and 24.00 h, and bled 24 h following ovariectomy (OVX). Between D2 and proestrus plasma E2 levels increased, and there was no change in any parameter of pulsatile LH release. However, OVX on D2 reduced plasma E2 levels and increased mean blood LH levels above proestrous values due to increases in LH pulse amplitude and frequency. Restoration of physiological proestrous levels of E2 reduced the increase in mean blood LH levels, by lowering pulse frequency to proestrous values and by greatly reducing pulse amplitude. However, LH pulse amplitude and mean blood LH levels were still higher than values on proestrus. PFF alone produced no alteration in any parameter of pulsatile LH release compared with saline-treated animals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
993.
To obtain estimates of the frequency of nosocomial infections nationwide, those occurring at the four major sites—urinary tract, surgical wound, lower respiratory tract and bloodstream—were diagnosed in a stratified random sample of 169,526 adult, general medical and surgical patients selected from 338 hospitals representative of the “mainstream” of U.S. hospitals. We estimate that in the mid-1970s one or more infections developed in 5.23 percent (± 0.16) of the patients and that 6.62 (± 0.24) infections occurred among every 100 admissions. Risks were significantly related to age, sex, service, duration of total and of preoperative hospitalization, presence of previous nosocomial or community-acquired infection, types of underlying illnesses and operations, duration of surgery, and treatment with urinary catheters, continuous ventilatory support or immunosuppressive medications. Seventy-one percent of the nosocomial infections occurred in the 42 percent of patients undergoing surgery and 56 percent in the 38 percent financed by Medicare, Medicaid or other public health care plans.  相似文献   
994.
BACKGROUND: Under the Indian Revised National TB Control Programme (RNTCP), smear-positive pulmonary tuberculosis (PTB) patients not confirmed as starting treatment are reported as 'initial defaulters'. SETTING: Twenty districts of Andhra Pradesh State, India. OBJECTIVE: To evaluate reasons for treatment non-initiation in smear-positive PTB patients diagnosed and reported as initial defaulters by the NTP. DESIGN: A cross-sectional survey conducted of all reported initial defaulters during the period July-September 2006. RESULTS: Of 1304 reported initial defaulters, 619 (47.5%) had been placed on treatment, having been incorrectly reported due to poor documentation of patients referred for treatment in the same district or whose treatment initiation was delayed until the subsequent quarter. Of the 685 (4.5% of the total diagnosed) who were confirmed initial defaulters, 350 (51%) were untraceable, 152 (22%) had died before treatment initiation, 38 (5.5%) were treated privately, 93 (13.5%) had other reasons (e.g., refusal of treatment, chronic case, etc.) and no data were available for 52 (8%). CONCLUSIONS: Nearly 5% of smear-positive PTB patients diagnosed in the study period were confirmed as not having initiated treatment under the RNCTP. Improvements in address recording may assist efforts to retrieve these patients for treatment. Additional evaluations are needed of improved counselling of TB suspects to prevent initial default, and of reasons for death before treatment initiation.  相似文献   
995.
A man known to have familial dysautonomia presented with a cardiac arrhythmia due to development of hiatal hernia and gastroesophageal reflux. Preoperative symptoms and assessment are described including use of power spectrum analysis of heart rate fluctuations which was consistent with enhanced parasympathetic stimulation. After surgical repair of hiatal hernia and fundoplication, bradycardia resolved, gastroesophageal reflux symptoms subsided, and the power spectrum analysis of heart rate confirmed decreased parasympathetic influence. Power spectrum analysis proved to be a useful adjunct in confirming preoperative autonomic imbalance and assessing the postoperative result. It is concluded that in individuals with disorders such as familial dysautonomia that are associated with autonomic dysfunction, cardiac arrhythmias may be a sign of esophageal pathology. Thus, cardiac evaluations should be accompanied by investigation of gastroesophageal structure and function and appropriate treatment may prevent a catastrophic arrhythmia.  相似文献   
996.
997.
998.
Chronic iliac osteomyelitis classically presents radiologically as an ill defined radiolucent lesion with moth eaten appearance along with periosteal reaction and sequestrum formation. Our case report presents a rare radiological picture of iliac bone osteomyelitis in the form of an expansile mutiloculated lytic lesion.  相似文献   
999.
1000.

INTRODUCTION

Nicorandil is a commonly prescribed antianginal medication that has been found to be associated with painful anal ulceration. The incidence of this complication is unknown. We have used the best data available to us to make an estimate of this figure in a health district with a remarkably stable population of approximately 200,000 people.

METHODS

Using an electronic search of all letters generated from colorectal and gastroenterology clinics as well as endoscopy reports from January 2004 to November 2010, patients with anal ulceration who were taking nicorandil were identified. Other causes of ulceration were excluded by biopsy in the majority of cases. The central hospital and community pharmacy database was interrogated to estimate the number of patients who were prescribed nicorandil over a six-year period (2004-2010).

RESULTS

A total of 30 patients (24 men, 6 women) with a median age of 79.5 years were identified who fulfilled the criteria of: taking nicorandil; having no other identified cause for anal ulceration; and achieving eventual healing after withdrawal of nicorandil. In the six-year period an estimated mean of 1,379 patients were prescribed nicorandil each year. The mean annual incidence of anal ulcers among nicorandil users is therefore calculated to be in the region of 0.37%.

CONCLUSIONS

Anal ulceration appears to occur in approximately four in every thousand patients prescribed nicorandil each year. Prescribing physicians should explain the risk of this unpleasant complication to their patients.  相似文献   
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