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101.

Purpose

Measurement of the testis is a more readily available method of estimating spermatogenesis. Doubt remains about the best instrument for measuring testicular volume. Lack of bias or accuracy of instruments has received too much emphasis in some studies, while to our knowledge no one has yet appropriately compared reliability statistically. We propose a simple new method for measuring testicular size based on visual comparison with graphic models, and describe the reliability and bias of this and 4 traditional methods.

Materials and Methods

Measurements of 42 adolescent testes were made in a certain sequence: graphic method, dimensional measurement, Prader orchidometer, ring orchidometer and ultrasound with ultrasound assumed to be the standard. Statistical analysis was based on the linear structural model.

Results

Statistical tests indicated that all 5 methods are equally reliable (R greater than 0.9). Although they are not equally accurate, actual testicular size can be calculated using each of these 5 methods and the equations of the linear structural model.

Conclusions

The new graphic method proposed in this study is as reliable as other well-known methods for measuring testicular size. Actual testicular volume can be estimated without bias and with equal reliability from any of the 5 methods using the equations of the linear structural model. This statistical approach is more relevant than the sole comparison of lack of bias or accuracy, which has been the main concern of previous studies.  相似文献   
102.
Summary SeventeenRhizobium japonicum cultures isolated from soybean nodules induced formation of nodules on taproots of soybean plants. All isolates reduced acetylene to ethylene to different extentsin vitro. Paper disc assay indicated that two insecticides, lindane (-1,2,3,4,5,6-hexachlorocyclohexane), chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate), and a fungicide, thiram (tetramethylthiuratn disulphide) individually or in combination caused significant inhibition of the growth ofR. japonicum No. 16.The effects of insecticide-fungicide seed treatments on the nitrogenase activity of soybean plants in nitrogen-fixing capacity, weights of leaves, stems, and nodules were determined. Thiram, singly or in combination with lindane and/or chlorpyrifos, significantly delayed growth of the plants and affected the activity of nitrogenase in the fixation of nitrogen 3 weeks after treatments. No drastic effect of any of the pesticide treatments on soybean plant growth was observed after 8 weeks.Contribution No., Research Institute, Agriculture Canada, London, Ontario.  相似文献   
103.
BACKGROUND AND PURPOSE: Previous studies have documented sex differences in the management and outcome of patients with cardiovascular disease. However, little data exist on whether similar sex differences exist in stroke patients. We conducted a study to determine whether sex differences exist in patients with acute stroke admitted to Ontario hospitals. METHODS: Using linked administrative databases, we performed a population-based cohort study. The databases contained information on all 44 832 patients discharged from acute-care hospitals in Ontario between April 1993 and March 1996 with a most responsible diagnosis of acute stroke. The main outcomes measured consisted of sex differences in comorbidities, the use of rehabilitative services, the use of antiplatelet therapy and anticoagulants (in elderly stroke survivors aged > or =65 years only), discharge destination, and mortality. RESULTS: Male stroke patients were more likely than female stroke patients to have a history of ischemic heart disease (18.1% versus 15.3%, respectively; P<0.001) and diabetes mellitus (20.1% versus 18. 7%, respectively; P<0.001), whereas female patients were more likely than male patients to have hypertension (33.8% versus 30.0%, respectively; P<0.001) and atrial fibrillation (12.9% versus 10.2%, respectively; P<0.001). There were no sex differences in the usage of in-hospital rehabilitative services. The overall 90-day postdischarge use of aspirin and ticlopidine was similar in stroke survivors aged 65 to 84 years. However, among stroke survivors aged > or =85 years, men were more likely than women to receive aspirin (36. 0% versus 30.7%, respectively; P<0.001) and ticlopidine (9.2% versus 6.8%, respectively; P=0.007). Use of warfarin was similar for the two sexes. Men were more likely than women to be discharged home (50. 6% versus 40.9%, respectively; P<0.001) and less likely to be discharged to chronic care facilities (16.8% versus 25.2%, respectively; P<0.001). The risk of death 1 year after stroke was somewhat lower in women than men (adjusted odds ratio 0.939, 95% CI 0.899 to 0.980; P=0.004). The mortality differences were greatest among elderly stroke patients. CONCLUSIONS: Elderly men are more likely than elderly women to receive aspirin and ticlopidine and equally like to receive warfarin after a stroke. Despite these differences, elderly women have a better 1-year survival after a stroke.  相似文献   
104.
Rate of stroke recurrence in patients with primary intracerebral hemorrhage   总被引:13,自引:0,他引:13  
BACKGROUND AND PURPOSE: Primary intracerebral hemorrhage (PICH) is a devastating illness with high early mortality. Hypertension is a major risk factor both for ischemic cerebrovascular disease and for intracranial hemorrhage. Survivors of PICH are at risk for both recurrent hemorrhage and ischemic cerebrovascular disease. We sought to determine the rate of recurrence of ICH or cerebral ischemia in a cohort of PICH patients at the Toronto Hospital, Toronto, Canada. METHODS: A retrospective search of computerized hospital records from 1986 to 1996 for patients with a discharge diagnosis of intracerebral hemorrhage (International Classification of Diseases, Ninth Revision-Clinical Modification [ICD-9-CM] code 431) was conducted to identify the index cases. Charts were abstracted for demographic and clinical characteristics. CT scans, MR scans, or radiologist reports were reviewed. To determine recurrence, the database was linked to the Ontario Provincial Government Vital Statistics Registry and to the Canadian Institute for Health Information database of hospital discharge abstracts. Logistic regression analysis was used to identify predictive factors for mortality after PICH. A Cox proportional hazards model was fitted to identify predictive factors for recurrent ICH or stroke. RESULTS: A total of 746 charts were identified by computer search. After abstraction, 423 index patients with PICH were identified. Of these, 27.4% died in the first 30 days of their admission. Predictors of death were age, intraventricular rupture of hemorrhage, and trilobar hemorrhage. The recurrence rate for PICH was 2.4% (95% CI 1.4% to 3. 9%) per year, whereas the recurrence rate for ischemic cerebrovascular disease was 3.0% (95% CI 1.8% to 4.7%) per year. The only significant predictor of readmission for ICH was lobar location of the index hemorrhage, with a hazard ratio of 3.8 (95% CI 1.2 to 12.0). CONCLUSIONS: PICH has a high 30-day mortality rate. Survival from the initial insult portends a moderate risk of recurrence of 2. 4% per year for PICH and 3.0% per year for ischemic cerebrovascular disease. Patients with PICH are at risk for both ischemic stroke or TIA and recurrent hemorrhage; thus, PICH may be a marker for ischemic stroke. Patients with lobar hemorrhage have a 3.8-fold increased risk of recurrent ICH.  相似文献   
105.
Liu HM  Huang YC  Wang YH  Tu YK 《Neuroradiology》2000,42(10):766-770
We report the effectiveness of low-concentration n-butyl-2-cyanoacrylate (NBCA)-Lipiodol-tungsten mixture (10–15 %) in the management of patients with aggressive or recurrent complex cavernous dural arteriovenous fistulae (CSDAVF). We treated five patients with complex CSDAVF with a low concentration of an NBCA-Lipiodol-tungsten mixture after catheterisation of the feeding arteries arising from the external carotid artery. Three had a recurrent CSDAVF after transarterial particulate embolisation. Three refused transvenous treatment or could not be treated in this way; two patients had also feeding dural branches of the internal carotid artery. All patients had complete resolution of symptoms and signs within a month of the procedure. No definite neurological complication was found during follow-up ranging from 12 to 36 months. Transarterial embolisation with low-concentration cyanoacrylate appears to be an effective alternative management of aggressive or recurrent CSDAVF. Received: 8 November 1999/Accepted: 2 March 2000  相似文献   
106.
目的观察双诺希(SHNX)胶囊对高脂血症大鼠血脂的影响。方法用高脂饲料喂饲大鼠建立高脂血症模型,随机将其分为正常对照组、高脂模型组、安妥明组、SHNX大剂量组、SHNX中剂量组和SHNX小剂量组6组,连续喂饲并灌胃给药1个月后,观察SHNX对高脂血症大鼠血脂水平的影响。结果SHNX能明显降低血清总胆固醇(TC)、血清甘油三酯(TG)含量,也能明显提高血清高密度脂蛋白亚组分胆固醇(HDL2-C)及高密度脂蛋白胆固醇(HDL-C)的含量。结论用SHNX治疗血脂紊乱大鼠有明显的效果。  相似文献   
107.
PURPOSE: Cyclophosphamide, epirubicin, and fluorouracil (CEF), compared with classical cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy. has lead to an improvement in relapse-free and overall survival in premenopausal women with node-positive breast cancer. We undertook this analysis to more accurately define the estimate of risk of secondary acute leukemia (sAL) following epirubicin-containing chemotherapy regimens. PATIENTS AND METHODS: We assessed the conditional probability of sAL among 1,545 women who received adjuvant (n = 1,477) or neoadjuvant (n = 68) chemotherapy in four National Cancer Institute of Canada Clinical Trials Group trials from 1990 to 1999. The risks associated with epirubicin-containing regimens (CEF or epirubicin and cyclophosphamide [EC]) and other regimens (doxorubicin and cyclophosphamide [AC] or CMF) were determined. RESULTS: A total of 10 cases of sAL were observed (eight acute myelogeneous leukemia, two acute lymphoblastic leukemia): seven among women treated with CEF, two who had received AC, and one following CMF. Using competing risk statistics, the conditional probability of sAL was 1.7% (95% confidence interval [CI], 0.5 to 3.6) among 539 women treated with CEF chemotherapy at a follow-up of 8 years, 0.4% (95% CI, 0% to 1.3%) among the 678 who received CMF, and 1.3% (95% CI, 0% to 4.7%) among the 231 treated with AC. The conditional probability of death from breast cancer at 8 years for the entire group of women treated with epirubicin-containing regimens in all four trials was approximately 34.9%. CONCLUSION: CEF chemotherapy for breast cancer carries a small increased risk of sAL compared with CMF. These estimates of acute leukemia risk are important in discussing treatment with women, especially patients with a lower risk of death from breast cancer, such as those with node-negative breast cancer.  相似文献   
108.
Otomo N  Motoyama K  Yu S  Shimizu Y  Margenthaler J  Tu F  Flye MW 《Surgery》2000,128(2):206-212
BACKGROUND: Tolerance to cardiac allografts can be induced in mice and rats by the injection of donor alloantigen into the thymus in combination with a CD4 T-cell-depleting antibody. CD8(+) cells in these animals are hyporesponsive to graft-specific alloantigens. Most of the CD8(+) T cells in the transgenic 2C mouse express a T-cell receptor specific for the class I major histocompatibility complex L(d+) locus. This study was designed to determine whether the adoptive transfer of these 2C T cells could precipitate rejection of a tolerant, completely major histocompatibility complex-mismatched L(d+) or L(d-) heart. METHODS: C57BL/6 mice (L(d-)) were given 10 x 10(6) cells of BALB/c (L(d+)) or dm2 (BALB/c background lacking L(d) [L(d-)]) splenocytes intrathymically and GK1. 5 (10 mg/kg) intraperitoneally. Twenty-one days later, BALB/c or dm2 hearts were transplanted. On the day of transplantation or after long-term allograft acceptance, recipients received naive 2C cells or 2C cells sensitized by in vitro mixed lymphocyte culture with BALB/c (L(d+)). RESULTS: Mean survival time of BALB/c cardiac allografts in untreated C57BL/6 mice was 7.3 days, although 73% of the mice that were pretreated with BALB/c splenocytes IT plus GK1.5 accepted the donor antigen-specific heart allografts indefinitely. All recipients that were pretreated with the intrathymic plus GK1.5 and that were injected with naive 2C cells at the time of heart transplantation experienced rejection of the BALB/c (L(d+)), but not the dm2 (L(d-)) hearts. In contrast, naive 2C cells could not reject tolerant (>30 days acceptance) BALB/c (L(d+)) hearts. 2C cells sensitized in vitro against L(d) were able to reject established BALB/c hearts but could not reject the L(d-) dm2 hearts. CONCLUSIONS: L(d)-specific 2C T-cell receptor transgenic T cells that are adoptively transferred to recipients will precipitate the rejection of accepted hearts that express class I L(d+) in mice rendered tolerant by an intrathymic injection of alloantigen plus anti-CD4 monoclonal antibodies.  相似文献   
109.
人乙型肝炎病毒x基因转基因小鼠模型的建立   总被引:16,自引:0,他引:16  
Tu Y  Qi Z  Yang P  Pan Y  Yu S  Du M  Li G 《中国医学科学院学报》2000,22(3):263-265
目的 建立人乙型肝炎病毒x(HBx)基因转基因小鼠模型。方法 用显微注射法制备转基因小鼠,用分子杂交法鉴定转基因小鼠HBx的整合与表达。结果 建立了人HBx的基因转基因小鼠模型。经Southern杂交鉴定得到17只转基因首建鼠。逢肝脏提取总RNA进行Northern杂交,结果显示17只首建鼠肝脏中均有HBx表达。结论 为从整体水平研究慢性乙肝炎患者诱发肝癌的作用机制及HBx的反式激活作用机制提供了  相似文献   
110.
胸骨后甲状腺肿物的手术处理   总被引:1,自引:0,他引:1  
为探讨胸骨后甲状腺肿物手术切除的进路方式,回顾性分析30年来外科治疗的结果。1965年至1994年间全部患者共87例,其中结节性甲状腺肿64例,占73.6%;甲状腺腺瘤13例,占14.9%;甲状腺恶性肿瘤10例,占11.5%。通过颈部入路手术切除的占70%(61/87),胸骨正中劈开切除的占16%(14/87),前切口开胸切除的占14%(12/87)。随着经验的积累,除误诊为纵隔其它来源的肿物外,1980年以后已不再行前切口开胸手术切除,1985年以后的43例中,只有1例胸骨后结节性甲状腺肿的患者行胸骨劈开手术,其余均从颈部入路手术。由于颈部入路相对并发症少、损伤小、安全可靠,建议对良性的胸骨后甲状腺肿物和部分恶性肿物行颈部衣领式切口手术。  相似文献   
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