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1.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
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目的:肺癌分期与肿瘤直径的关系已被证实是一个预后指标,因此被纳入1986年肺癌分类的国际系统。近年来由于CT飞速发展,人们可以诊断出更小的肺癌,于是有人提倡对肺癌Ⅰ期进一步分期,即根据肿瘤直径小于还是大于30mm,将无确切远处淋巴结转移的病例(Ⅰ期病例)细分为Ⅰa和Ⅰb期。在诊断无症状(即潜伏)的肺癌时,CT普查的开展使人们考虑肿瘤大小的预后价值。在此我们对CT普查诊断的无症状潜伏型肺癌作了分期与大小关系的报道。 相似文献
4.
LY Zhang S Jejeebhoy IH Shah LH Zhang J Hsia W Im-em 《The European journal of contraception & reproductive health care》2013,18(3):147-154
Objective The concerns about the potential threats of human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS) have increased, since, in China, there is a lack of sexual education and condom use is rare. A community-based survey was conducted in September 2001 in Changchun city among 1227 unmarried young people aged 15-24 years (619 males and 608 females) to assess risky sexual practices and the obstacles to accessing appropriate contraceptive and other services. Method The study comprised a survey employing self-administered questionnaires, as well as key informant interviews, focus group discussions and in-depth interviews. This paper investigates the factors associated with young people's access to contraceptive services. Results Results showed that 16% of young people had experienced premarital sexual intercourse and, among them, only 48.2% used contraceptive methods during the first sexual intercourse; 29.9% used a condom. Drug stores were the main source of contraceptives. Conclusions While data are sparse, findings suggest that the hostile and judgmental attitudes of providers, as well as the lack of counseling and privacy, were the key obstacles that unmarried youth encountered in their search for contraceptive services. Findings suggest the need for a reorientation of the contraceptive services to focus on unmarried youth, and generally to make contraceptive services more accessible to young people. 相似文献
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The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis. 相似文献
7.
RS de Vreeze D de Jong IH Tielen HJ Ruijter PM Nederlof RL Haas F van Coevorden 《Modern pathology》2009,22(2):223-231
Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum. 相似文献
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Jade A Flindell Judith C Finn Nicholas P Gibson Ian G Jacobs 《Emergency medicine Australasia : EMA》2009,21(6):465-471
Objective: Describe short‐term mortality and hospitalization outcomes in patients undergoing troponin testing in Western Australia tertiary public hospital ED. Methods: Retrospective cohort study of adults presenting to urban tertiary ED between July 2000 and December 2004, and undergoing troponin inhibitory or tropomyosin binding testing. Patient data relating to ED attendance, troponins, hospitalization and death were linked using probabilistic data linkage. Troponin results were dichotomized (normal/abnormal) according to hospitals' cut‐offs across various time periods. Presentations undergoing ED troponin testing, provided that it was not within 28 days of a previous discharge involving ED troponin testing, met study inclusion criteria. Logistical regression analyses quantified risk of subsequent hospitalization and death. Results: A total of 119 646 troponin tests were performed during 83 635 ED presentations involving 54 214 patients. For the 73 965 ED presentations meeting the study criteria, 6779 (9.2%) recorded an abnormal peak troponin level and 168 (2.5%) of these presentations were discharged directly from ED. After adjusting for covariates, those discharged directly from ED with abnormal troponin results were significantly more likely to die within 2 days (OR 60.4, 95% CI 31.9–114.2), 7 days (OR 31.2, 95% CI 17.9–54.3) and 28 days (OR 19.4, 95% CI 12.5–30.1) of discharge, compared with those with normal troponin results. Adjusted odds of subsequent hospital admission within 28 days following discharge from ED were 3.3 (95% CI 2.4–4.5) times greater for presentations with abnormal versus normal troponin results. Conclusion: An abnormal ED troponin result appears to be associated with increased risk of subsequent hospitalization and death within 28 days of discharge. 相似文献