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81.
100对615系种鼠,常规饲养繁殖,观察33个月(终生),其乳腺癌发病率为5.5%(11例全部发生于经产雌鼠),低于肺腺癌(11%,22例,雌雄各半)而居第二位,故615系小鼠仍属低乳癌品系。对615系小鼠的46例自发乳腺癌进行了病理形态学检查分析:瘤细胞可分为小、中、大三类。组织分型属A型者18例,多由小细胞及少量中细胞构成;属B型者28例,除小细胞外往往可见较多的中细胞甚或主要由大细胞与中细胞构成。B型乳腺癌的分化程度似较A型者为低。转移主要发生于肺部。7例经镜检证实属乳腺癌的肺转移瘤,其原代瘤属A型者1例,属B型者6例。肺转移瘤的组织像与原发瘤基本相同者4例;而细胞变大,呈实心排列,显示分化程度低于原发瘤者3例。  相似文献   
82.
PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2+ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice.  相似文献   
83.
PURPOSE: This study examined the association between maternal smoking before and during the first trimester of pregnancy and spontaneous abortion.

METHODS: We have been conducting a hospital-based case-control study on risk factors for spontaneous abortion in the greater Milan area. We collected information from 782 cases of spontaneous abortions and 1543 controls (women who delivered at term healthy infants).

RESULTS: With respect to never smokers, the odds ratio (OR) were 0.7 (95%, confidence interval (CI), 0.5–1.0) for women who quit smoking and 1.3 (95% CI, 1.0–1.6) for those who continued during pregnancy. Women who smoked more than 10 cigarettes/day in the first trimester were at increased risk of miscarriage, with an OR of 1.4 (95% CI, 1.0–2.1). No relationship was evident between the number of cigarettes smoked before conception and the risk of abortion. Likewise, no association emerged between paternal smoking and miscarriage. Moreover, no significant interaction or modification effect was obtained when strata of age and other major characteristics were investigated.

CONCLUSIONS: The risk of abortion associated with cigarette smoking during the first trimester of pregnancy was measurable and noticeable in this population, and accounted for 9% (95% CI, 6–13%) of all cases. The increased risk of spontaneous abortion in women smoking during pregnancy is a further reason to encourage pregnant women to quit.  相似文献   

84.
Spontaneous ovarian hyperstimulation mimicking an ovarian tumour   总被引:1,自引:1,他引:0  
Ovarian hyperstimulation syndrome in a spontaneous singletonpregnancy is exceedingly rare. We report a case of ovarian hyperstimulationpresenting as bilateral ovarian masses in association with spontaneouspregnancy, occurring in a woman with disturbed liver function.A possible mechanism is discussed.  相似文献   
85.
The influence of a fraction obtained from Galeopsis ladanum L. on the central nervous system of rodents was examined. The results of these investigations show that the fraction impeded CNS activity. It is practically nontoxic and at a dose of 2000 mg/kg i.p. it does not have a soporific influence on mice. It reduces considerably the spontaneous locomotor activity of mice as well as the locomotor activity of mice stimulated by caffeine, but did not influence the locomotor activity induced by amphetamine. The extract did not exhibit a synergetic effect with barbiturates. The results suggest that the pharmacological activity of the extract resembled the activity of drugs which generally depress the CNS, being on the border between ataractic and sedative drugs.  相似文献   
86.
The distribution of mannan binding protein (MBP) in blood donorsera was determined by enzyme-linked immunosorbent assay toestablish normal concentrations. Abnormally low MBP concentrationswere found in 16% (21 out of 135) of female partners and 14%(15 out of 108) of male partners of couples experiencing recurrentmiscarriage, compared with <5% of obstetrically normal controls(P < 0.005). This relationship was even stronger (9.5 versus1.0%) and more significant (P < 0.002) when only subjectspresumed to be homozygous for the mutant allele responsiblefor MBP deficiency were considered. By immunohistochemistry,MBP could be demonstrated in first trimester placenta. We suggestthat low concentrations of MBP within the feto-placental unitincrease susceptibility to fetal loss, possibly via an infection-inducedplacental cytokine imbalance.  相似文献   
87.
<正>心跳骤停(cardiac arrest,CA)和蛛网膜下腔出血(subarachnoid hemorrhage,SAH)均是急诊科常见的急危重症,CA可见于多种疾病的各个阶段,复苏成功率不高,甚至造成CA的病因不甚明确。SAH典型表现为剧烈头痛、呕吐、脑膜刺激征,诊断并不困难。而以CA为首发症状的SAH,由于心肺复苏无法常规进行头颅CT检查,给诊断增加了困难。本文通过对16例以CA为首发症状的SAH患者进行回顾性研究,来提高SAH-CA的快速病因诊断,避免漏诊误诊。  相似文献   
88.
Fatt and Katz (Nature 166:597-598, 1950; J Physiol 117:109-128, 1952) attributed miniature endplate potentials (MEPPs) to the action of a standard quantity of transmitter, the quantum (Del Castillo and Katz, J Physiol 124:560-573, 1954). Quantal packets of transmitter were proposed to be preformed (Del Castillo and Katz, In CNRS Paris (Ed): "Microphysiologie comparée des éléments excitables" 67:245-258, 1957) and stored in large numbers in the motor nerve terminal. Statistical analyses of intervals between MEPPs and numbers of quanta composing small endplate potentials indicated that quantal release was a random process and that release sites functioned independently of each other. With the discovery of synaptic vesicles it was proposed that each contained one quantum of transmitter. The quantal-vesicular hypothesis (Del Castillo and Katz, as cited above) fails, however, to explain amplitude distributions of MEPPs that are skewed and/or that show multiple peaks (Kriebel et al., Brain Res Review 15:167-178, 1990). The drop formation process (Shaw, "The Dripping Faucet as a Model Chaotic System," Santa Cruz, CA: Aerial Press, Inc., 1984) was shown to generate amplitude classes of drops that were similar to classes of MEPPs which suggested that rapid changes in quantal size and ratios of skew- to bell-MEPPs could be explained with a simple dynamic process which determines quantal size at the moment of release (Kriebel et al., as cited above, 1990). Further similarities between miniature endplate currents (MEPCs) and the formation of drops are reported here. We found that rapid changes in MEPC amplitudes and time courses, which accompany an increase in frequency, mimic changes in drop sizes that accompany increases in flow rate. MEPC intervals have a minimum and their distributions are comparable to those of drop intervals. During an increased rate of transmitter release, MEPP amplitudes and intervals were positively correlated. The results suggest that spontaneously released transmitter "packets" are formed at the moment of release and that transmitter supply to the process that forms packets is continuous.  相似文献   
89.
90.
Recurrent respiratory papillomatosis (RRP) is the most common benign tumour of the larynx, affecting both children and adults. We present a series of 25 patients, including 10 cases of juvenile multiple, 8 cases of adult solitary, and 7 cases of adult multiple RRP. Biopsy tissue from each patient was screened by Southern blot hybridization and polymerase chain reaction for the presence of human papillomavirus (HPV) DNA. Sera from patients and age- and sex-matched controls were tested for the presence of HPV-specific antibodies using a synthetic pep-tide derived from the minor capsid protein (L2) of HPV 6/11. By Southern blot hybridization and/or polymerase chain reaction, biopsies from all patients were positive for HPV 6/11 DNA. There was no difference in antibody response between cases and controls. Female cases and controls had significantly higher antibody titers than male subjects. A correlation was observed between the HPV-specific antibody level and the number of surgery-necessitating recurrences. © 1994 Wiiey-Liss, Inc.  相似文献   
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