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91.
Percutaneous dilatational tracheostomy is frequently performed as an alternative to traditional surgical open tracheostomy with many reported benefits. Despite its relative safety and widespread acceptance, complications can be associated with the procedure itself or long-term. We present four cases where there was difficulty with decannulation because of exuberant obstructive granulation tissue. In each case, the percutaneous tracheostomy involved the cricoid cartilage.  相似文献   
92.
Acute catatonic syndromes occurring in the context of various medical and neuropsychiatric conditions, including schizophrenia, have been shown to respond well to benzodiazepines (BZD). However, there have been no studies specifically designed to address the BZD treatment response of persistent catatonic states. Eighteen patients with clinically stable chronic schizophrenia, who also displayed enduring catatonic features, underwent a 12-week long, random assignment, double-blind, placebo-controlled cross-over trial with lorazepam (6 mg/day). A comprehensive assessment, including the subjects’ clinical and motor (catatonic as well as drug-induced movement disorders) condition, was performed at baseline and four weekly intervals thereafter. Pre-existing medication was kept constant throughout the study. Lorazepam had no effect on the subjects’catatonic signs and symptoms, suggesting that acute and chronic catatonic syndromes associated with schizophrenic illness might have a different neurobiological basis. Received: 25 May 1998/Final version: 22 September 1998  相似文献   
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A cyto- and myeloarchitectonic study reveals the presence of a distinct cortical zone ("area POa") in the lower bank of the intraparietal sulcus of the rhesus monkey. Using both autoradiographic and silver impregnation techniques, an analysis of cortical connections shows two overlapping projections to this sulcal zone. These come from (1) the middle portion of the preoccipital gyrus (area OA) and (2) the rostral inferior parietal lobule (area PF).  相似文献   
95.
The effect of various pesticides and derivatives on mitochondrial electron transport systems was assessed. DDT, DDE, TDE, Kelthane, chlorobenzilate, chloropropylate and Acarol were found to be inhibitory towards both heavy beef heart mitochondrial (HBHM) NADH-oxidase and succinoxidase enzyme systems. Dichlorobenzophenone andp-chlorophenol were less inhibitory towards the HBHM NADH-oxidase and did not inhibit the succinoxidase enzyme system. DDA did not inhibit either of the electron transport systems. Carbaryl was not inhibitory towards both HBHM oxidase systems, whereas its degradative product dihydroxynaphthalene was inhibitory at the same concentration. Furadan, Matacil, Baygon and Dimetilan were only slightly inhibitory towards the mitochondrial NADH-oxidase system and did not inhibit the succinoxidase system. Zectran was inhibitory towards the NADH-oxidase system and was not inhibitory towards the succinoxidase system. DDT, DDE and TDE, dihydroxynaphthalene and 1-naphthol inhibited the NADH-oxidase enzyme system on the substrate side of cytochrome c, whereas Kelthane inhibited on the oxygen side.Contribution to Regional Project W-45, Residues of Pesticides and Related Chemicals in the Agricultural Environment-Their Nature, Distribution, Persistence, and Texicological Implications. University of Nevada Agricultural Experiment Station No. 432.  相似文献   
96.
The normal progressive physiological and visual effects of aging and its influence on the ability of contact lenses to provide ametropic correction is examined in this article. Of primary significance is the aging eye's perceptual ability especially in the mesopic range of vision. In addition, a recap of current available techniques is included for correction of presbyopia with contact lenses from the perspective of prescribing for an aging patient--not merely a patient who has lost only the ability to accommodate. One of the hallmarks of the profession of optometry has been its traditional support of the premise that patients should be provided with the best possible optical correction. While there are presbyopic patients who can achieve satisfactory vision via the contact lens modalities now in use, the physiological influences discussed here have been generally ignored by the profession. A redefinition of the criteria indicating patient "success" has evolved from achieving satisfaction through excellent vision derived from the optimum optical correction, to satisfaction obtained through patient selection and indoctrination to wear an optically inferior device. Unless the physiological, visual, and psychological effects of aging are adequately compensated by future contact lens designs, most elderly patients will remain likely to return to spectacles as the deficiencies of contact lens correction become progressively more apparent to them.  相似文献   
97.
98.
A 30-year-old patient with tardive dystonia, who had failed to respond to cessation of neuroleptics, placebo, diazepam, biperiden, propranolol, and clonidine, had an impressive response to courses of electroconvulsive therapy (ECT) on three successive trials.  相似文献   
99.
100.
Objective: In an effort to understand the mechanism underlying the improved pregnancy rate observed in IVF cycles when gonadotropin-releasing hormone analogues (GnRH-a) are applied, we investigated a possible relationship between treatment variables and oocyte-nuclear maturity. Design: Nuclear maturity was retrospectively assessed in cumulus-free, denuded oocytes, obtained from women undergoing micromanipulation-assisted IVF treatment following controlled ovarian hyperstimulation with GnRH-a and menotropins. Setting: The setting was the infertility and IVF unit of a tertiary academic medical center. Participants: Two hundred twenty-one patients underwent 435 treatment cycles. Main Outcome Measure: This was the proportion of germinal vesicle-intact immature (GVII) oocytes. Results: One hundred fifty-four of the 3520 oocytes studied (4.4%) were in the GVII stage. These oocytes were found in 66 of the treatment cycles (15.2%) and in 54 of the patients (24.4%). Cycles in which GVII oocytes were detected did not differ from those in which all the aspirated oocytes were mature in the following respects: patient age, type and duration of infertility, controlled ovarian hyperstimulation protocol and time of ovum pickup. However, the GVII group was characterized by a significantly higher peak estradiol level, as well as a higher number of mature follicles visualized sonographically (diameter, >14 mm) and oocytes retrieved. Conclusions: Comparing the present findings with previously published data, it appears that the inclusion of GnRH-a in the stimulation regimen is associated with a lower proportion of immature oocytes. A higher occurrence of oocyte-nuclear immaturity is apparently associated with a significantly better ovarian response to stimulation. The high incidence of immature oocytes observed in patients with normospermic partners and low fertilization rates in previous cycles may suggest that the fertilization failure in some of these cases is due to oocyte, rather than sperm, dysfunction.  相似文献   
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