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81.
The hypothesis that differences in drug effects of risperidone and haloperidol on negative symptoms in schizophrenia are secondary to effects on positive, extrapyramidal, and depressive symptoms was investigated by means of an analysis of the data from the USA-Canada risperidone double-blind randomized clinical trial of 523 chronic schizophrenic patients. Regression analyses in the total sample and within treatment groups confirmed a strong relationship between changes in negative symptoms and the other variables studied (R2=0.50–0.51,p<0.001). Only depressive symptoms did not contribute significantly to these results (p>0.10). Path analysis showed that the greater mean change (p<0.05) of negative symptoms with risperidone compared to haloperidol could not be fully explained by correlations with favourable effects on positive and extrapyramidal symptoms. The relationship between shift in extrapyramidal symptoms and shift in negative symptoms failed to reach statistical significance; however, there was a clear tendency in the expected direction in both treatment groups.  相似文献   
82.
Changes in semen parameters are presented for 4708 patients treated for infertility. The largest group comprised patients with oligoasthenozoospermia of various grades (57.7%). Improvement in the seminal state was noted in 70.3%. The percentage of achieved normospermia increased proportionally to the initial semen state. Pregnancy rate also increased proportionally to the initial seminal state. Among the patients' wives 20.4% conceived: 28.2% of these pregnancies had occurred after having achieved normospermia, while in 71.8% the seminal states were still below the accepted normal values.  相似文献   
83.
The 2-(2-Bromophenyl)-acetaldehyde acetals 8 are treated with n-BuLi and the aldehydes 7 and 11 to form the hydroxyacetales 9 and 12, respectively. 9 is cyclized under acidic conditions to the epoxybenzoxocine 2; analogously 12 yields the epoxydibenzoxocine 14.  相似文献   
84.
85.
The post-lumbar puncture syndrome (PLPS) can best be explained by prolonged spinal fluid leakage owing to delayed closure of a dural defect. Its incidence after spinal anaesthesia is much lower than after diagnostic lumbar puncture (LP). This difference could be caused by a strand of arachnoid, which might enter the needle with the outflowing cerebrospinal fluid (CSF) during diagnostic LP and upon removal of the needle be threaded back through the dura to produce prolonged CSF leakage. To find a technique that further reduces the incidence of PLPS, this hypothesis was tested by evaluating the effect that reinserting the stylet before removing the needle had on the incidence of PLPS. By reinserting the stylet to the tip of the needle, the hypothesized strand would be pushed out, thereby reducing the frequency of PLPS. Sprotte’s “atraumatic needle” (21 gauge) was used for LP. A total of 600 patients participated in the prospective study. They were randomized into two groups and questioned about their complaints every day for up to 7 days after the LP. All LPs were performed by two experienced neurologists (T.B., M.S.). In 300 patients, the stylet was reinserted to the tip of the needle; in the other 300 it was not reinserted. Whereas 49 of the 300 patients without reinsertion developed PLPS, only 15 of the 300 patients with reinsertion did. This significant difference (16.3 vs 5.0%, P < 0.005, chi square test) supports our hypothesis. On the basis of our results, we recommend reinserting the stylet before removing the needle in order to reduce the incidence of PLPS. Received: 30 September 1997 Received in revised form: 9 March 1998 Accepted: 20 March 1998  相似文献   
86.
Summary During the past few years, a new tumor type has emerged in the pediatric and adolescent group of cancer patients, which has been designated malignant peripheral neuroectodermal tumor (MPNT). This tumor has some clinical and pathological signs in common with either soft-tissue sarcomas or classic Ewing's sarcoma, but is defined as a distinct entity because of its immunohistological characteristics. The tumor expresses neuronal markers, but the pattern varies: chromogranin, neuron-specific enolase, synaptophysin, protein S-100 and others. MPNT can occur in the urogenital region. The differential diagnosis on clinical grounds must include Ewing's and soft tissue sarcomas, and also Wilms' tumor and its variants. MPNT are often wide spread in the urogenital region when first diagnosed. Response to radiotherapy and combination chemotherapy is limited. Radical surgery is not always possible. The prognosis therefore remains rather poor at this time. A selection of MPNT patients is presented to demonstrate the various problems associated with this diagnosis. MRI and CT of all patients showed large tumors with direct infiltration of the surrounding structures. MRI is the best imaging modality for diagnosis and therapy monitoring in these tumors, because of its high soft-tissue contrast.  相似文献   
87.
88.
There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model.  相似文献   
89.
To study the possible influence of colonic diverticula on the risk of peritonitis of enteral (intestinal) origin in patients undergoing continuous peritoneal dialysis, a barium enema was carried out as a pretreatment investigation in 129 consecutive patients starting CAPD over a 9-year period. In this prospective study comprising 3103 patient months, a total of 44 (15% of all) episodes of peritonitis with micro-organisms of enteral origin occurred in 30 of the 129 patients. The estimated probability of developing such an episode was 16% and 24%, respectively, within 1 or 2 years of treatment. Diverticula (greater than or equal to 1) were found in 54 (42%) of all patients. In all cases the following factors: greater than or equal to 10 diverticula, diverticular size of greater than or equal to 10 mm and diverticula in the ascending, transverse, or descending colon, significantly increased the risk of developing peritonitis of enteral origin (P less than 0.05). Neither diverticula in the sigmoid colon nor diverticulitis, as assessed by radiological findings, were identified as risk factors. Enteral episodes (as defined in this study) appear to represent mainly microperformations of existing diverticula; such episodes should probably be regarded as and handled differently from episodes due to major perforations of the colon secondary to diverticulitis. We conclude that diverticular disease of the non-sigmoid colon is a risk factor for peritonitis in CAPD.  相似文献   
90.
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