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971.
A prospective trial was undertaken to evaluate the efficacy of stimulated in-vitro fertilization (SIVF) and stimulated intrauterine insemination (SIUI) in couples with unexplained and mild male factor infertility. In all, 80 couples were allocated to treatment with SIVF or SIUI, both treatments following the same protocol [clomiphene citrate and follicle stimulating hormone (FSH) injection], except that higher doses of FSH were used in the SIVF treatment cycles. Initially, 41 couples were allocated to and started treatment with SIVF but eight cases were eventually converted to SIUI because of under-response. Similarly, although 39 couples were initially allocated to SIUI treatment, five of these converted to SIVF because of over-response. The treatment cycles that were converted either to SIUI or to SIVF were not considered as treatment failures but as treatment changes and so were included in the analyses. Of the final 38 SIVF cycles, four were cancelled (dysfunctional response), failed fertilization occurred in five cycles and 29 subjects reached embryo transfer. There were two biochemical pregnancies [positive human chorionic gonadotrophin (HCG) only], two clinical abortions and seven live births. Of the final 42 SIUI cycles, only two were cancelled, insemination being performed in the remaining 40 cases. The result was one clinical abortion, three ectopics and eight live births. The proportion of cycles with positive HCG was identical (28.9% per cycle treated for SIVF and 28.6% for SIUI) and the livebirth rates were also not different (18.4% per cycle treated for SIVF and 19.0% for SIUI). The cost per maternity of SIUI was approximately half that of SIVF (Pounds Sterling 1923 versus Pounds Sterling 4611) and so we conclude that, as SIUI had an efficacy that was not significantly different from SIVF (using similar protocols) but was more cost-effective, it must be considered the more appropriate form of management for the treatment of unexplained and mild male factor infertility. Indeed, it is hard to justify the routine use of IVF, as a first approach, in unexplained infertility.   相似文献   
972.
 The Y-maze was used to assess spontaneous alternation behaviour in mice to examine possible interactions between the N-methyl-D-aspartate receptor channel blocker dizocilpine and purine receptor agonists and antagonists. Scopolamine reduced spontaneous alternation. Dizocilpine also produced a dose-dependent reduction in alternation scores, which was accompanied by an increase in locomotion. The selective A1 adenosine receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (CPX) had no effect when administered alone, or in combination with scopolamine. However, when co-administered with dizocilpine, CPX reversed both the deficit in alternation behaviour and also the increase in locomotion induced by dizocilpine. The A1 selective agonist N 6-cyclopentyladenosine (CPA) had no effect on either locomotion or alternation scores when administered alone, but in combination with scopolamine, CPA attenuated the scopolamine-induced deficit. CPA had no significant effect on the dizocilpine-induced deficit. The A2 selective agonist N 6-[2-(3, 5-dimethoxyphenyl)-2(2-methylphenyl)-ethyl]adenosine (DPMA), had no effect on spontaneous alternation when administered alone, but did cause a depression of locomotion. DPMA had no significant effect when co-administered with scopolamine, but reversed the deficit in spontaneous alternation, and the increase in locomotion induced by dizocilpine. The A2 selective antagonist 3,7-dimethyl-1-propargylxanthine (DMPX) had no effect when given alone or in combination with scopolamine, but when co-administered with dizocilpine, DMPX reversed the reduction in spontaneous alternation caused by dizocilpine. It is concluded that dizocilpine has a detrimental effect on spontaneous alternation which is mediated partly by A1 and A2 adenosine receptors. Received: 21 March 1996 / Final version: 6 November 1996  相似文献   
973.
We have carried out a prospective study on the impact of computed tomography (CT) and ultrasonography (US) on the management of patients with carcinoma of the ovary. Seventy-eight CT and 88 US scans were performed on 94 patients. Clinicians decided patient management prospectively at the time the CT and/or US was ordered. Clinical assessment differed from the result obtained by CT or US in 45% of cases (35/78 and 40/88, respectively). CT and US altered patient management in only a minority of cases (14/78, 18% and 9/88, 10% respectively). Even when the scan and clinical assessments differed, management was only altered on 14/35 (40%) occasions after CT and on 9/40 (23%) occasions after US, a difference which was not significant. In patients with clinically undetectable disease, management was altered by CT on 17% of occasions and by US on 10%. We conclude that in patients with carcinoma of the ovary CT and US alters patient management in a minority of cases. In view of current financial restrictions in health care, clinicians should be more selective in the use of these imaging techniques. Furthermore, we recommend that similar prospective studies are performed for other clinical situations.  相似文献   
974.
Geometry of the humeroulnar joint   总被引:4,自引:0,他引:4  
Clinical results with elbow prostheses have been disappointing. A detailed knowledge of elbow joint geometry and mechanics is necessary to improve prosthetic design. In this study, the humeroulnar articulation of four human cadaver elbows was examined using surface analytic methods. In this article, the location of the transverse axis of elbow flexion-extension is suggested in relation to well-defined landmarks, the medial and lateral epicondyles, and subsequently to the line connecting their most lateral points--the transepicondylar line. The geometry of the structures responsible for the carrying angle is discussed, as is the extent of cartilage-covered bearing areas of the lower humerus and upper ulna. Implications pertaining to prosthetic design and surgical technique resulting from this study are discussed.  相似文献   
975.
976.
OBJECTIVES: Clinical and genetic characterisation of families in the west of Scotland with familial hemiplegic migraine. METHODS: Families with familial hemiplegic migraine were identified via probands attending the regional paediatric neurology and child development centre. All available family members were assessed clinically and genetic linkage studies for the known familial hemiplegic migraine gene locus on chromosome 19 were carried out on three families. RESULTS: Seven unrelated kindreds with familial hemiplegic migraine were identified. Clinical information was obtained on 138 family members, 27 of whom fulfilled the International Headache Society criteria for familial hemiplegic migraine. Whereas the severity, duration, frequency, and temporal progression of acute hemiplegic migrainous attacks showed pronounced variability within and between families, and even in the same individual over time, no true clinical heterogeneity of the condition was apparent. Genetic linkage analysis gave results consistent with linkage to the familial hemiplegic migraine gene locus on chromosome 19p in one family. In the other two families, evidence against linkage was obtained. There was no significant clinical difference between these three families. CONCLUSIONS: This study provides characterisation of the clinical features of familial hemiplegic migraine in a British population. Significant variability was found in the frequency and character of migraine attacks within and between families, and no true clinical heterogeneity was identified. On the other hand, further evidence for genetic heterogeneity of the condition was found.  相似文献   
977.
BACKGROUND: Vagus nerve stimulation (VNS) alters both concentrations of neurotransmitters or their metabolites and functional activity of central nervous system regions dysregulated in mood disorders. An open trial has suggested efficacy. METHODS: This 10-week, acute, randomized, controlled, masked trial compared adjunctive VNS with sham treatment in 235 outpatients with nonpsychotic major depressive disorder (n = 210) or nonpsychotic, depressed phase, bipolar disorder (n = 25). In the current episode, participants had not responded adequately to between two and six research-qualified medication trials. A two-week, single-blind recovery period (no stimulation) and then 10 weeks of masked active or sham VNS followed implantation. Medications were kept stable. Primary efficacy outcome among 222 evaluable participants was based on response rates (>/=50% reduction from baseline on the 24-item Hamilton Rating Scale for Depression [HRSD(24)]). RESULTS: At 10-weeks, HRSD(24) response rates were 15.2% for the active (n = 112) and 10.0% for the sham (n = 110) groups (p = .251, last observation carried forward [LOCF]). Response rates with a secondary outcome, the Inventory of Depressive Symptomatology - Self-Report (IDS-SR(30)), were 17.0% (active) and 7.3% (sham) (p = .032, LOCF). VNS was well tolerated; 1% (3/235) left the study because of adverse events. CONCLUSIONS: This study did not yield definitive evidence of short-term efficacy for adjunctive VNS in treatment-resistant depression.  相似文献   
978.
The region of the brachial plexus in the root of neck and axilla was examined by computed tomography (CT) in 62 patients attending the Royal Marsden Hospital. Forty-two of these patients had been treated by surgery and subsequent radiotherapy for carcinoma of the breast. Computed tomography was able to identify varying grades of abnormality that were ascribed to radiation fibrosis. Twenty-eight patients had neurological symptoms affecting the arm or hand on the treated side and CT changes were seen in 96%. The grading and significance of these CT abnormalities is discussed. The patients had been treated by two different radiotherapy techniques (three-field and four-field) which utilised either a large or small treatment fraction. The higher grades of abnormality on CT were seen in 57% of those treated with the large fraction size and 27% of those treated with the small fraction size. However, the changes on CT did not relate to the different radiotherapy techniques.  相似文献   
979.
980.
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