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1.
Summary The majority of lymphocytes separated from tumor cell suspensions were T cells. Conjugates of T lymphocytes and tumor cells were often seen. Variable numbers of T cells exhibited signs of activation such as the ability to form stable E rosettes and attachment to normal and malignant cells (a phenomenon designated natural attachment: NA). A proportion of T cells activated in vitro by allogeneic stimulation regularly exhibit these properties. The T cell-tumor conjugates in the suspensions may represent the NA phenomenon, but they could also be the product of T cells that adhere on the basis of specific recognition of cell surface antigens.Abbreviations BBS balanced salt solution - E rosettes rosettes formed with sheep erythrocytes - EA rosettes rosettes formed with ox erythrocytes coated with anti-ox IgG - FCS fetal calf serum - MLC mixed lymphocyte cultures - NA natural attachment - PBL peripheral blood lymphocytes - SRBC sheep erythrocytes - T lymphocytes thymusderived lymphocytes  相似文献   

2.
Activation of human blood T lymphocytes in mixed lymphocyte culture (MLC) causes a reduction in the net negative surface charge, as indicated by the reduction in the electrophoretic mobility. Concomitantly, the activated cells acquire new properties, including the ability to form “stable” E rosettes, and attach to normal and malignant cells of the same species (natural attachment (NA)). These properties were found to be expressed by lymphocytes within the low electrophoretic fractions (cells with low negative charge) of the MLC populations. The formation of stable E rosettes and natural attachment capacities of human thymocytes were also found to correlate with the amount of surface negative charge. The slowly migrating (less negative charged) cortical thymocytes, reported earlier as being able to form stable E rosettes, were found also to exhibit NA activity. Medullary thymocytes carrying a high net negative surface charge lack these characteristics. We consider it likely that the reduction of negative charge during activation of peripheral T cells, facilitates cell-to-cell contacts, and thus prepares the (activated) cells to perform cooperative interactions with other cell types, and express the lytic activity of T cells.  相似文献   

3.
Whereas studies in awake subjects have demonstrated that chest wall compliance (Ccw) is low in obese subjects, the one study performed on paralyzed obese subject found Ccw to be normal. The purpose of this study was to measure Ccw in awake obese subjects with the pulse-flow technique, a method which appears to detect respiratory muscle relaxation. Seven normal males, 14 obese males, and 8 obese females [body mass index (BMI) varied from 20 to 83 kg/m2] were studied in the seated position. Ccw was measured by blowing air at a constant flow into the mouth and lungs for approximately 2 s and calculated by dividing airflow in liters per second by the change in esophageal minus body surface pressure in centimeters of water per second. In normal and obese subjects we found no correlation between BMI and Ccw. We conclude that obesity does not decrease Ccw.  相似文献   

4.
Rectal mucosa is relatively susceptible to pathological processes and frequently it is affected by various diseases. However, there is a notable lack of quantitative data regarding normal rectal mucosa, which would provide a reference for histoquantitative studies of the pathologically changed tissue. Therefore, we obtained the tissue from 27 healthy patients subjected to diagnostic rectoscopy during active screening for asymptomatic cancer of the large intestine, in which no disease was found. Using computer-aided morphometric analysis, we studied all structural elements of the rectal mucosa. The patients were divided into four groups according to the age and sex: adult males, elderly males, adult females and elderly females. The patients under 60 years of age were grouped as adult and those older than 60 years as aged subjects. A decreased height of surface epithelium was registered in both elderly male and female groups. This finding, however, was significant only when adult and elderly male groups were compared. The tendency towards reduction of the mucosal height was also registered comparing male adult and elderly groups. The number of crypts per 0.1 mm2 of tissue increased with aging in both males and females, whereby the crypts were always more numerous in males than in females. The increase in number of crypts in male subjects was accompanied by a decrease in their diameter and perimeter. The changes associated with ageing were discrete and affected only the male subjects.  相似文献   

5.
Electrophysiological age and sex differences in visual pattern responsivity were investigated. Pattern reversal evoked potentials (PREPs) and visual evoked potentials (VEPs) to patterned and unpatterned flashes were recorded from 20 normal subjects in each of 4 groups: young females and males aged 25–35 years and older females and males aged 55–70 years. PREP waves N70-P100 and P100-N150 from the older women were significantly larger than those from subjects in the other groups; mean amplitudes for the young females, young males and older males were not different. A similar effect, unusually large potentials for the older women, was obtained for VEPs, but only for VEPs elicited by patterned flashes and recorded from occipital scalp, i.e., an area overlying visual cortex which is sensitive to lines and edges. Our findings suggest that the visual system of older females is unusually responsive to patterned stimuli.  相似文献   

6.
P Cushman  R Khurana 《Life sciences》1977,20(6):971-980
T and B cell rosettes were serially determined before, during, and after a four week cycle of tetrahydrocannabinol (THC) smoking in 10 hospitalized subjects. The early T cell rosettes were significantly fewer during the period of THC smoking and tended to return toward baseline after smoking, whereas no changes were seen in the seven simultaneously studied controls. Both the THC smokers and controls showed no change in their normal values for WBC, % lymphocytes, B cell rosettes (complement receptor) and late T cell rosettes. The data suggest that T cells, present in nearly normal numbers in the smokers, had reduced capacities to form early rosettes during and directly related to THC smoking. While the immunological significance of reduced early rosette formation is unclear, the data suggest that further immunological study of marijuana smokers would be indicated.  相似文献   

7.
A sexually dimorphic nucleus exists in the dorsal region of the ferret preoptic/anterior hypothalamic area (POA/AH), and is called the male nucleus of the POA/AH (MN-POA/AH) because it is found only in males. Development of the MN-POA/AH was studied in male ferrets, and for comparison a sexually nondimorphic ventral POA/AH nucleus was studied in both sexes. The MN-POA/AH was conspicuous in males as early as embryonic day 37 (E37) of a 41-day gestation, and its volume increased until postnatal day 56 (P56). No nucleus was present in the dorsal POA/AH of females at any age. The densities and average somal areas of cells in the dorsal POA/AH were similar in males and females at E33, before the MN-POA/AH could be visualized. However, at E37 and E41 dorsal cells were greater in density and/or somal area in males than in females, accounting for the appearance of a nucleus in males at these ages. To insure that the dorsal POA/AH nucleus seen in males at E37 and E41 was the presumptive MN-POA/AH present in adult males, pregnant ferrets were given progesterone and either implanted subcutaneously (s.c.) with testosterone (T) or ovariectomized and implanted s.c. with the aromatase inhibitor, 1,4,6-androstatriene-3,17-dione (ATD), on day 30 of gestation. As predicted from previous studies in which subjects were sacrificed in adulthood, formation of a dorsal POA/AH nucleus was promoted in female ferrets by T, and blocked in males by maternal ovariectomy and ATD treatment for animals sacrificed at E41. Much evidence suggests that behavioral sexual differentiation is accomplished in the male ferret between age E28 and P20. The MN-POA/AH is present and potentially functional in males during a considerable portion of this perinatal period.  相似文献   

8.
The sex-limitation of sex-influenced esterase (ESSI) in serum of rats carrying Es-Sia allele was re-examined. ESSI was detected in immature males and females, and orchiectomized rats as well as mature females whereas ESSI in normal males rapidly disappeared with puberty. The rats orchiectomized at weaning temporarily lost ESSI around the age of sexual maturation, thereafter, ESSI reappeared. When orchiectomized rats were administered testosterone, synthesis of ESSI was suppressed as in normal adult males. Effect of ovariectomy was not recognized. The exceptional strain named SI 3 of which normal mature males have a significant level of ESSI has been established, although the level in the males is lower than that in the females of the same strain.  相似文献   

9.
Ovariectomized female rats received either bilateral radiofrequency lesions of the ventromedial nucleus of the hypothalamus (VMH) or control treatments and were tested for copulatory activity following either estrogen (E) alone, or E plus progesterone (P) administration. In separate experiments the females were tested in two testing apparatuses both of which allowed the test females to control their contacts with sexually active males. One of the testing apparatuses also allowed the females to control their contacts with sexually inactive males and ovariectomized females. Females receiving VMH lesions engaged in fewer coital contacts with sexually active males than sham-operated females in the E plus P condition. Lesioned females also tended to spend less time with sexually active males than did sham operates in both the E and E plus P hormonal conditions. The VMH-lesioned females did not differ from the sham-operated females in the ability to display lordosis during the coital contacts or the frequency and duration of visits to the inactive males or ovariectomized females. The sham-operated females did have some transitory alterations in copulatory behavior in comparison to unoperated control females.  相似文献   

10.
Monocular pattern-shift visual evoked potentials (PSVEPs) were obtained in 26 neurologically and ophthalmologically normal elderly community volunteers (mean age 59.4, males 15, females 11), and compared with similarly obtained data in 26 sex-matched young subjects (mean age 28.1). Elderly males were age-matched with elderly females, and young males were age-matched with young females. Data analyses at both the midoccipital-linked ears and midoccipital-midcentral derivations revealed that the combined-eye mean P100 latency in the elderly as a whole was significantly longer than the young sex-matched controls (P < 0.02). However, the latency in the elderly males was not significantly different from that of sex-matched young males, or age-matched elderly females. The latency in young female subjects, on the other hand, was significantly shorter both when compared to that of age-matched young males (P < 0.01) and sex-matched elderly females (P < 0.01). The differences in other PSVEP variables, namely, interocular P100 latency differences, P100 amplitudes and interocular P100 amplitude ratios were not significant between the groups and subgroups studied.It is concluded that females account for the major contribution towards the longer P100 latency in the elderly.  相似文献   

11.
House fly (Musca domestica) males are highly attracted to dead female flies infected with the entomopathogenic fungus Entomophthora muscae. Because males orient to the larger abdomen of infected flies, both visual and chemical cues may be responsible for the heightened attraction to infected flies. Our behavioral assays demonstrated that the attraction is sex-specific-males were attracted more to infected females than to infected males, regardless of cadaver size. We examined the effect of E. muscae on the main component of the house fly sex pheromone, (Z)-9-tricosene, and other cuticular hydrocarbons including n-tricosane, n-pentacosane, (Z)-9-heptacosene, and total hydrocarbons of young (7 days old) and old (18 days old) virgin females. Young E. muscae-infected female flies accumulated significantly less sex pheromone and other hydrocarbons on their cuticular surface than uninfected females, whereas the cuticular hydrocarbons of older flies were unaffected by fungus infection. These results suggest that chemical cues other than (Z)-9-tricosene, visual cues other than abdomen size, or a combination of both sets of cues might be responsible for attraction of house fly males to E. muscae-infected females.  相似文献   

12.
A study was conducted in subtropical northern Mexico (26 degrees N) to determine whether the presence of estrous females can improve the response of seasonally anovulatory goats to the introduction of bucks in the group. The induction of estrous activity was studied in three groups of anovulatory lactating goats during seasonal anestrus. These females were of the Mexican Creole breed. In the control group (sexually inactive (SI), n = 20), two control (SI) bucks exposed to normal seasonal daylength variations were used. In the second group (SI + E, n = 20 + 3), two control males were also used, but in addition, three females of the group were in estrus at the time of male introduction. In the third group (sexually active, SA + E, n = 19 + 4), anovulatory females were exposed to two bucks made sexually active by exposure to 2.5 months of long days (16L:8D) followed by two subcutaneous 18 mg melatonin implants, and four estrous females were also present when introducing the bucks. In all groups, males were introduced on 15 March and estrous detection was conducted twice daily for 15 days. The sexual activity of the bucks was observed from 08:00 to 10:00 h during the first five days of exposure to females. More females displayed estrous behavior in the first 15 days following the introduction of the males in the SA + E group (18/19) as compared with the SI or SI + E groups (2/20 and 0/20, respectively; P < 0.001). No difference was observed between the two latter groups. Thirteen females of SA + E group showed a second estrus between days 6 and 11 (short estrous cycle duration: 5.4 +/- 0.4 days). By contrast, in the SI group none showed a second estrus. The sexual behavior of the males in the SA + E group was greater as compared with that of the males in SI and SI + E groups (over 80% of the total sexual activity recorded in the three groups; P < 0.001). By contrast, no differences were found between SI and SI + E males. These results indicate that the presence of estrous females alone at the time of buck introduction is not sufficient to induce an adequate stimulation of seasonally inactive males. The use of sexually active bucks is necessary to induce reproductive activity in anovulatory females, whereas preparation of the bucks with long days followed by melatonin implants allows them to gain such a capacity.  相似文献   

13.
Castrated zebra finches receiving one of six hormone treatments were given three weekly tests with different females and their sexual behavior was contrasted with that of two control groups consisting of intact or castrated males given implants of cholesterol. The six hormone treatments were: two aromatizable androgens, testosterone (T) and androstenedione (AE); two nonaromatizable androgens, androsterone (AN) and dihydrotestosterone (DHT); an estrogen, estradiol (E); or a combination of E + DHT. Half the males receiving DHT received the 5α-isomer, half received the 5β-isomer. Castration significantly reduced the proportion of males which courted females, total courtship displays, high-intensity courtship displays, beak wiping activity, and significantly increased the latencies to show these behaviors compared to intact males. Castrated males never attempted to mount a female. All of these measures of courtship and copulatory behavior were restored to normal levels only by treatments providing both estrogenic and α-androgenic metabolites (i.e., T, AE, E + αDHT). AE was clearly the most effective of these, raising behavior significantly above normal on several measures. AN treatment was more effective than αDHT on all measures and not significantly different from intact birds on some. Treatment with E, αDHT, βDHT, or E + βDHT was totally ineffective. Surprisingly, females only solicited males whose hormone treatments provided estrogenic metabolites. Not only did they solicit males given aromatizable androgens, which showed high rates of courtship activity, they also solicited males given E or E + βDHT, some of which never even courted. Castration and hormone treatment also affected body and syringeal weight, but in opposite directions. Castration increased body weight while decreasing syringeal weight. Hormone treatments providing α-androgenic metabolites decreased body weight and increased syrinx weight. Treatments supplying estrogen as well were slightly more effective.  相似文献   

14.
15.
Hand surface area (HSA) has been utilized for burned skin area estimation in burn therapy, heat exchange in thermal physiology, exposure assessment in occupational toxicology, and the development of manual equipment/ protective gloves in ergonomics. The purpose of this study was to determine the hand surface area to the total body surface area (BSA) and derive a formula for estimating HSA. Thirty-four Korean males (20-60 years old; 158.5-187.5 cm in height; 48.5-103.1 kg in body weight) and thirty-one Korean females (20-63 years old; 140.6-173.1 cm; 36.8-106.1 kg) participated as subjects. The HSA and BSA of 65 subjects were directly measured using alginate. The measurements showed 1) the surface area of the hand had a mean of 448 (371-540) cm(2) for males, and 392 (297-482) cm(2) for females. 2) The hand as a percentage of the total body surface area for males and females was 2.5% and 2.4% respectively, showing no significant difference. 3) The hand as a percentage of BSA by body shape was 2.5% for the lean group and 2.3% for overweight people (p=0.001). 4) When estimating the surface area of a hand, formulae based on hand length or hand circumference were more valid than formulae based on height and body weight. We obtained the following formula for estimating HSA: Estimated HSA(cm(2))=1.219 Hand length(cm) x Hand circumference(cm).  相似文献   

16.
This investigation compares the age- and sex-related changes in growth hormone (GH) response to growth hormone releasing hormone (GHRH) in normal subjects using an appropriate pharmacokinetic model. Twenty-five subjects (14 males and 11 females) aged 23-89 yr received a single intravenous bolus dose (1 microgram/kg) of GHRH-40 solution. Plasma GH concentration-time profiles are best characterized by a biexponential equation (or one-compartment model) with first-order release and disappearance rates and an equilibration lag time. The harmonic mean release rate half-life is similar for both sexes (males: 12.6 min vs. females; 11.4 min) but significantly different across age groups (23-35 yr: 7.2 min vs. 50-89 yr: 16.8 min). The mean disappearance rate half-life and GHRH-equilibration time lag for females (33.6 and 20.4 min, respectively) and the higher age group subjects (32.4 and 21.6 min, respectively) are significantly longer than those of males (22.8 and 9 min, respectively) and the lower age-group subjects (21.6 and 8.4 min, respectively). The mean metabolic clearance rate of GH is significantly lower (p less than 0.02) for females than for males (3.1 vs. 4.83 ml/hr.m2). However, the production rate and the amount of GH released by the pituitary for our subjects appear to be very similar for both males (8.7 micrograms/hr.m2 and 4.65 micrograms/m2) and females (9.33 micrograms/hr.m2 and 5.11 micrograms/m2).  相似文献   

17.
Actual homicides may be considered the tip of an iceberg, reflecting evolved coercive impulses and motivations found in normal individuals as well as the criminally violent. Two studies examined reports of homicidal fantasies in normal subjects. In the first study, subjects were asked whether they had ever had a homicidal fantasy, and if so, they were asked several questions about their most recent fantasy. In the second study, subjects were asked about the frequency of homicidal fantasies in several categories. The majority of subjects in both studies reported at least one fantasy. Males tended to recall more homicidal fantasies than did females (in Study 1, 73% vs 66%; in Study 2, 79% vs 58% of males and females, respectively). Males also reported longer and more detailed fantasies, and were more likely to imagine strangers and coworkers as victims. Females' recent fantasies were more likely to involve family members than were males, but that appears to be due to the fact that males had more fantasies about members of other categories, and not due to a tendency for males to have fewer homicidal fantasies about family members than do females. There was some evidence of greater fantasies involving step-parents, especially when one considered the amount of time subjects had spent living with step-, as opposed to genetic, parents. Results are discussed in terms of Daly and Wilson's evolutionary model of actual homicides.  相似文献   

18.
A population-based study was undertaken to evaluate linkage between single-nucleotide polymorphisms known as risk factors and type 2 diabetes in an Indian population. The study population was comprised of 40 normal glucose-tolerant individuals (21 males and 19 females) and 40 type 2 diabetes patients (21 males and 19 females). The genes and their corresponding single-nucleotide polymorphisms that we screened were VDR (rs 731236 and rs 1544410), IL-6 (rs 1800795), TCF7L2 (rs 7903146) and TNF-α (rs 1800629). The risk alleles were more frequent in the subjects with type 2 diabetes, except for the TNF-α gene, which was very infrequent in the population; the normal allele occurred at high and similar frequencies in both normal and diabetic individuals.  相似文献   

19.
Differences between males and females in the effects of regular physical training on the heart were investigated by echocardiography in 579 male (nonathletes: 122, athletes: 457) and in 336 (nonathletes: 84, athletes: 252) female subjects of variable age. The age groups were: children (<15 yr.), adolescent-young (15-18 yr.), young adult (19-30 yr.), adult (31-45 yr.) and people elder than 45 yr older (45<). Hypertrophy characterised by relative left ventricular muscle mass (rel.LVMM) of the athletic heart was manifest also in the females, but in comparison with the males female values were much lower both in the unconditioned and in the conditioned groups. In people belonging to the oldest groups no differences were seen either between the males and females or between athletes and nonathletes. In comparing nonathletic subjects, females showed smaller left ventricular contractility as reflected by a higher LVET/QT ratio and an increased ability of diastolic relaxation as indicated by a higher E/A ratio. Physical training induced a more marked development when the initial level was lower, namely, in the contractility of the females, and in the compliance of the males. No intersex difference was seen in the modified regulation of the athletic heart, characterised by a lower resting heart rate and slower circumferential shortening velocity (VCF).  相似文献   

20.
Peripheral blood from 120 healthy subjects, of whom 59 were young (35.5 +/- 9.6 years) and 61 aging (69.2 +/- 4.2 years), was examined for the proportions and numbers of lymphocyte populations, with a battery of surface markers. Absolute lymphocyte count and T,B and third population cells were comparable in both groups. Tgamma cell proportions were significantly (p less than 0.001) increased in aging subjects when compared with the young subjects. However, this difference was more significant (p less than 0.001) when aged females were compared with the young females as compared to aged males vs young males (p less than 0.05). When data were anlayzed for absolute numbers of Tmu and Tgamma cells, a similar significant decrease in Tmu, and increase in Tgamma cells were observed. Interestingly, when these data were anlayzed according to gender, significant differences in Tmu and Tgamma cell number were observed between young and old females but not between young and old men. Implications of these results are discussed.  相似文献   

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