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1.
The present study was carried out to assess the endocrine status and liver function in adult cows reared in polluted environment around different industrial units in India.The effect on endocrine system was examined by determination of plasma level of thyroid hormones, thyroxin (T4) (n=269) and triidothyronin (T3) (n=269), stress hormone cortisol (n=266), and reproductive hormones such as estradiol (n=84) and progesterone (n=84) in cows (>3 years) reared around different polluted industrial and non-polluted areas.The respective blood lead and cadmium concentration was also determined in all the cows.The mean plasma levels of both T3 and T4 were significantly (P<0.05) higher around lead zinc smelter (2.43+/-0.26 and 41.1+/-2.9nmol/L) and closed lead cum operational zinc smelter (1.81+/-0.16 and 42.4+/-6.2nmol/L), where the mean blood lead level (0.86+/-0.06 and 0.51+/-0.09mug/ml) was also significantly higher than that of cows (0.07+/-0.01mug/ml) from unpolluted areas.Regression analysis of data from 269 cows revealed a significant (P<0.01) positive correlation between the blood lead and plasma T3 (r=0.287) and T4 (r=0.173).The correlation between thyroidal hormones and the blood cadmium concentration (r=-0.079 and -0.48; P>0.05) was not significant.Plasma cortisol level had also a non-significant (P>0.05) correlation (r=-0.092) with blood lead level.However, the mean cortisol level (4.02+/-1.96nmol/L) of cows in phosphate rock mining areas was significantly (P<0.05) higher than that of controls (1.98+/-0.70nmol/L). The mean plasma estradiol level was significantly (P<0.05) higher in cows around closed lead cum operational zinc smelter (47.1+/-19.5pg/ml) than that of the control animals (21.8+/-3.9pg/ml) and in rest of the areas, the difference did not reach the statistical significance (P>0.05).The serum biochemical analysis in 36 cows around lead-zinc smelter with the highest mean blood lead level (0.86+/-0.06mug/ml) amongst all the industrial/urban areas surveyed, and in 15 animals from non-polluted areas revealed a significant positive correlation between blood lead and serum ALT (alanine transaminase) (r=0.688, P<0.01) and AST (aspartate transaminase) (r=0.390, P<0.01) and a negative correlation with serum total lipids (r=-0.337, P<0.05), total protein (r=-0.449, P<0.01) and albumin(r=-0.662, P<0.01). It is concluded from the study that the natural exposure to lead in polluted environments disturbs the endocrine profile and the higher blood lead level alters serum biochemical parameters indicative of liver functions.  相似文献   

2.
The interactions between copper, iron, zinc, arsenic, cadmium and lead were studied in the livers of 12 ewes of the Improved Wallachian breed after experimentally induced intoxication with cuprous oxide from industrial emission. The highest correlation coefficient was recorded between the concentrations of copper and zinc in the livers of the experimental ewes (r = 0.916) and its value was at a significance level of p less than 0.05. The interaction between copper and arsenic in the liver of the experimental animals corresponded to a correlation coefficient of r = 0.359 and that between copper and cadmium corresponded to r = 0.129. The lowest correlation coefficient in the livers of the experimental animals was recorded between copper and lead (r = 0.073). As to the relationships between the remaining elements, the highest correlation coefficient (r = 0.667) was obtained between the contents of zinc and cadmium in the livers of the experimental ewes. The interaction of copper with the other risky metals after experimental intoxication was limited by the concentration of the studied elements in the industrial emission as well as by the course of the disease itself.  相似文献   

3.
将96头体重27kg左右杜长大生长猪,随机分为2组,每组设3个重复(公、母各半),分别饲喂添加0、10.0mg/kg镉的饲粮,进行了83d的饲养试验,期间每隔两周固定从每个重复中选2头猪(公、母各半)前腔静脉采血。饲养试验结束后,从每组中各选取12头试验猪(公母各半)屠宰,并采集血清、内脏器官样品测定铁、铜、锌的含量。结果表明:添加10.0mg/kg镉显著影响猪的生长性能,其日增重降低18.6%(P<0.05),饲料转化率降低15.1%(P<0.05);10.0mg/kg镉引起了一些组织中铁含量的显著降低(P<0.05)及铜含量的显著升高(P<0.05),肾锌水平显著提高(P<0.05),而心脏、胰脏中锌含量显著降低(P<0.05);添加镉对淋巴结和心脏铁含量、淋巴结和胰脏铜含量及肝脏和脾脏锌含量无显著(P>0.05)影响。  相似文献   

4.
In a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute of Animal Health (FLI) over 12 weeks with 20 cows of the German Holstein Breed the influence of different copper and zinc contents in the ration on their concentration in blood serum, liver and hair was tested. All animals received a diet based on maize- and grass silage ad libitum. The animals were divided in two groups with 10 cows each; group A received a concentrate according to their milk yield with a copper and zinc content as recommended (GfE 2001), whereas group B was offered a concentrate with roughly the double amount of copper and zinc. At the beginning and at the end of the trial a sample of blood, pigmented hair and a liver bioptate was taken from all animals to evaluate the incorporation of copper and zinc in these tissues. In serum and pigmented hair the copper concentrations did not differ between the two groups [13.4 for Group A and 12.5 micromol/L for Group B in serum respectively 6.8 (Group A) and 7.4 mg/kg DM (Group B) in pigmented hair]. Only the copper concentration in the liver was influenced by the different feeding. The higher copper content for group B resulted in a significantly higher copper concentration in the liver (506 mg/kg DM compared to 383 mg/kg DM). The liver is the best indicator organ for a sufficient copper supply. An increase in the zinc content in the ration resulted neither in higher zinc concentrations in serum (15.1 in Group B in comparison to 13.4 micromol/L for Group A) nor in higher zinc concentrations in liver (140 for Group B and 112 mg/kg DM for Group A) and pigmented hair (130 in Group A and 123 mg/kg DM in Group B). There is a significant correlation between copper intake and copper concentration in the liver (r = 0.46), whereas the correlation between zinc intake and zinc concentration in the liver is only tendencially (r = 0.23). The three tested samples serum, liver and cow hair are not qualified to reflect exactly a sufficient zinc supply.  相似文献   

5.
Samples of switch hair, blood, and urine were obtained periodically over 5.5 months from 11 Angus and 13 Angus-Charolais cows grazing either all-grass or grass-legume swards. Liver samples were obtained at the end of the study. Hair growth rate and mineral concentrations in switch hair (magnesium [Mg], copper [Cu]), blood serum (Mg, Cu), urine (Mg), and liver (Cu) were determined. Significant (P less than 0.05) hair-growth rate differences were observed among sampling periods (daily mean = 0.58 +/- 0.01 mm). Angus black-pigmented switch hair contained more (P less than 0.001) Mg than did the light-pigmented Angus-Charolais hair. The effect of season was observed on hair Mg and Cu and on serum Mg (P less than 0.01). Serum and hair Mg concentration correlated in both breed groups after removal of individual cow treatment effects (Angus: r = 0.58, P less than 0.001, n = 64; Angus-Charolais: r = 0.46, P less than 0.001, n = 76). Likewise, urine Mg and hair Mg concentrations correlated (Angus: r = 0.35, P less than 0.05, n = 53; Angus-Charolais: r = 0.26, P less than 0.05, n = 63). Sward type had a pronounced effect on serum and urine Mg concentrations and a slight effect on hair Mg concentrations (P less than 0.10) only during midsummer. Cattle with switch hair Mg values less than 25 to 30 mg (light pigmentation) and 100 to 125 mg (black pigmentation)/kg of dry matter (DM) may be hypomagnesemic.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
Neutrophil function, blood micronutrients, and cortisol concentrations were measured in 43 clinically healthy postparturient Holstein cows. Estimated 305-day mature equivalent milk production and neutrophil function were related to results of the blood micronutrient concentrations and neutrophil function tests. Cattle had low to normal zinc concentrations; normal to high selenium, vitamin E, and cortisol concentrations; and normal copper concentrations. Blood selenium (P = .03) and zinc (P = .027) concentrations were both significant predictors of neutrophil adhesion, and selenium (P < .001) was a significant predictor of neutrophil cytochrome C reduction (superoxide production). Fourteen of 20 (70%) cattle with blood selenium concentrations > 300 ng/mL had neutrophil adhesion, and 15 of 20 (75%) had cytochrome C reduction above the mean value for this group. There was also a significant correlation (r = 0.331; P = .037) between cytochrome C reduction and estimated milk production. These findings suggest that neutrophils from postparturient dairy cows with higher blood concentrations of selenium have greater potential to kill microbes, and that cattle with greater superoxide production may have higher milk production.  相似文献   

7.
During the period 1973–1977, a number of mute swans (Cygnus olor) were submitted to the National Veterinary Institute in Stockholm and examined post mortem. Organ tissues from 58 swans were chemically analysed for concentrations of lead, cadmium, copper, zinc, iron and manganese. In 10 swans (17 %), elevated residues of lead were found indicating intoxication. Cadmium concentrations were significantly higher in adult than in juvenile swans; also in swans from the Swedish east coast compared with specimens from the west coast. Remarkably high copper concentrations were often found, with one exception yet without any signs of intoxication. High zinc and cadmium concentrations were often found in the same swans. The findings of iron and manganese were not remarkable.  相似文献   

8.
Reference values were established for some haematological and serum biochemical constituents in Bactrian camels (Camelus bactrianus) in China. The contents of seven trace elements in the blood, hair, liver, kidney, heart, spleen, lung, cerebrum, cerebellum, rib, ovary, pancreas and gluteal muscle of Bactrian camels were also measured. Some of these values are reported for the first time for Bactrian camels in China. Most haematological and serum biochemical values were similar to those of cattle, yaks, sheep and dromedary camels, but the mean serum albumin concentration and the albumim/globulin ratio were significantly higher than those in other ruminants and the mean thyroxine concentration was half that in dromedary camels. The liver contained the highest concentrations of copper, zinc, manganese and iron, and the renal cortex contained the highest concentration of selenium. The concentrations of selenium, cobalt, zinc, manganese and molybdenum in the tissues were within the reference ranges for other ruminants, but the mean iron and copper concentrations in the liver were significantly higher than those in other ruminants.  相似文献   

9.
为研究微量元素含量与乳房炎发生的相关性,采集健康荷斯坦牛与乳房炎奶牛的乳汁各15份,用火焰原子吸收光谱法（FAAS）测定了6种矿物元素铁（Fe）、铜（Cu）、锌（Zn）、锰（Mn）、镁（Mg）、钴（Co）含量,并进行了对比分析。结果表明患乳房炎乳汁中Cu、Fe、Co和Zn含量显著低于正常乳汁（P〈0.05或P〈0.01）,而Mn和Mg含量差异不显著（P〉0.05）。乳房炎与微量元素含量具有相关性。  相似文献   

10.
Epidemiological studies have indicated incidences of 32.9% and 27.8% for rickets and osteomalacia, respectively, in Bactrian camels (Camelus bactrianus), but there is an increased incidence under drought conditions, sometimes reaching 75%. We have found that concentrations of phosphorus and copper in forage and soil samples in a drought affected area were significantly lower than in a control area or normal reference values (P < 0.01) ; the mean Ca:P ratio in the forages was 50:1. The phosphorus content of blood and hair from affected camels was significantly less than that in controls (P < 0.01) and concentrations of copper in the liver and kidney were significantly lower in affected camels than control animals (P < 0.01); the concentrations of triiodothyronine (T(3)), thyroxine (T(4)) and parathyroid hormone (PTH) in the serum from affected animals were significantly higher than those from healthy controls (P < 0.01); serum inorganic phosphorus and ceruloplasmin levels were lower than those in the controls (P < 0.01 or P < 0.05); the concentrations of serum alpha-globulin and beta-globulin were significantly higher in the affected camels than in the healthy controls (P < 0.01). The pathological changes seen in camels affected with rickets included porous, brittle, light, osteoporotic bones that were susceptible to fractures and had less resistance to cutting and sawing. Wrist joints were enlarged with an apparent bowing of the long bones in forelimb and with typical broadening of the epiphyses. In adult female camels, many enlarged scars were often seen in ribs indicating earlier fractures. The disease could be cured with supplementary bone meal, phosphate or mineral mixtures and in field investigations clinical signs disappeared within 15 days. Over the same period, the concentrations of phosphorus and alkaline phosphatase in blood returned to normal. The disease may be effectively prevented by use of mineral blocks (block salt licks) or dosing orally with copper, selenium and cobalt soluble glass boluses. We conclude that rickets and osteomalacia are mainly caused by phosphorus and copper deficiencies in the pasture.  相似文献   

11.
The life span and cumulation of heavy metals in the liver of 12 ewes of the Improved Wallachian breed were investigated in relation to feeding pollutants from a copper works. The total intake of copper, iron, zinc, arsenic, cadmium and lead was 466.8; 1253.93; 111.67; 34.75; 0.091; 2.13 mg per experimental animal/day, respectively. The average life span of ewes in the experimental group was 77 days. The difference between the first and the last animal which died from copper intoxication was 18 days. The concentration of copper in the liver of sheep who died from intoxication by this metal (2138.28 +/- 1090.96 mg. kg-1 in dry matter) was significantly higher (p less than 0.01) if compared with the control ewes (212.9 +/- 58.33 mg. .kg-1 in dry matter). In the course of observations no direct dependence between the concentration of copper in the liver and the life span of experimental animals was confirmed. The content of iron and zinc in the liver of experimental animals was within the reference range; the difference in zinc was statistically significant when compared with the control group (p less than 0.01). The intake of pollutants from the copper works increased significantly the concentration of arsenic and lead in the liver of experimental animals (p less than 0.01) if compared with the control group. The amount of cadmium in the liver of experimental ewes was 0.304 +/- 0.22 mg. .kg-1 and in the control ewes 0.285 +/- 0.10 mg.kg-1 in dry matter; no significant difference was determined at the same time.  相似文献   

12.
In the period from January 1983 to December 1985 we examined thirty-five samples of commercial feed mixtures for pigs and thirty samples of pigsty dust deposition from large pig-houses in a region with extensive mining (lignite extraction) situated in the Hodonín district. In comparison with the contents of contaminants in the feed mixtures over the period from January 1983 (1/83) to June 1984 (6/84), the zinc and lindane concentrations increased to 213.3% (P less than 0.01) and 133.3%, respectively, from July 1984 (7/84) to December 1985 (12/85). The concentrations of copper, manganese, lead, cadmium, mercury (P less than 0.05), DDT (P less than 0.01) and aflatoxin B1 in the feed mixtures decreased. The highest permissible amount of contaminants in the feed mixtures was exceeded in the 1/83-6/84 period in cadmium (limit value 0.3 mg per kg) and mercury (limit value 0.1 mg per kg), in the 7/84-12/85 period only in zinc (limit value 250 mg per kg). In comparison with the values of contaminants in pigsty dust deposition recorded from January 1983 to June 1984, the lead concentration increased to 555.5% in the 7/84-12/85 period, lindane concentration rose to 569.0% (P less than 0.01), zinc concentration to 220.5% (P less than 0.01), the copper, manganese, cadmium, mercury concentrations (P less than 0.05) decreased, and the concentrations of DDT, aflatoxin B1 and polychlorinated biphenyls also dropped. It is desirable to evaluate in regular intervals the spectrum of contaminants both in feed mixtures and in pigsty dust deposition and to monitor other potential sources of contaminants in the pig-houses.  相似文献   

13.
为观察母鼠围产期铅暴露对仔鼠各组织微量元素含量的影响及N-乙酰半胱氨酸(NAC)的保护效应,采用电感耦合等离子体质谱法(ICP-MS)测定低水平铅暴露后的仔鼠血液、大脑、骨骼、肝脏和肾脏等组织中的铅、锌、铜、铁、锰和硒等微量元素的含量。结果表明,与对照组相比,染铅组所测组织铅含量均极显著升高(P<0.01),锌含量均极显著降低(P<0.01);肝脏铁含量、肾脏硒含量及骨骼铁、铜、硒含量均显著降低(P<0.01或P<0.05)。NAC拮抗组与染毒组比较,各组织铅含量显著降低(P<0.01或P<0.05),血液和肾脏锌含量显著升高(P<0.05),其他元素含量无明显差异(P>0.05)。  相似文献   

14.
The clinical signs of a disorder in yaks (Bos grunniens), known locally as "swayback ailment," in the Qing Hai-Tibetan Plateau are described. The purpose of this study is to investigate the possibility that swayback ailment is iron (Fe)-induced copper (Cu) deficiency. The mean concentrations of Cu in soil and forage from affected areas and unaffected areas are similar and within the normal ranges. The mean concentrations of Cu in blood and hair from the affected yaks was significantly lower (P < 0.01) than that in unaffected yaks. The mean concentrations of Fe in soil and forage were significantly higher (P < 0.01) in affected than in unaffected areas. Affected yaks showed a hypochromic microcytic anemia and a low level of ceruloplasmin. Oral administration of copper sulphate prevented and cured the disease. We conclude that "swayback disorder" of yaks is caused by secondary Cu deficiency, mainly due to the high Fe content in forage.  相似文献   

15.
The influence of different copper and zinc contents in rations on blood serum concentrations was tested in a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute for Animal Health (FLI). A total of 60 German Holstein breed cows (38 first lactating and 22 second lactating cows) were tested. All animals received a diet based on maize‐ and grass silage ad libitum. The animals were divided into two groups with 30 cows each. Group A received concentrates supplemented with copper and zinc as recommended, whereas Group B was offered a concentrate with roughly double the amount of copper and zinc. Blood samples were taken several times during the lactation. The concentrations of copper and zinc in the serum were measured and correlations between trace element intake and their serum concentrations were calculated. The mean dry matter intake was significantly higher for cows in the second lactation (19.1 kg/day) than for cows in the first lactation (16.4 kg/day), whereas the DM‐intake was constant in the different feeding groups (17.3 and 17.4 kg/day). The correlation between feed intake in the first and the second lactation was r = 0.76. The copper concentration in the serum was not influenced by the different feedings (11.9 and 12.5 μmol/l), but high variations were found between the cows. The influence of the lactation number was not significant (12.1 and 12.4 μmol/l). In contrast to copper, the zinc concentration in the serum was significantly higher for Group B (14.0 μmol/l) than for Group A (12.2 μmol/l), respectively, for second lactating cows (13.8 μmol/l) in relation to 12.7 μmol/l for first lactating cows. The individual variation was also high as for copper. Neither the correlation between copper intake and copper serum concentration nor the correlation between zinc intake and zinc serum concentration was significant.  相似文献   

16.
The content of iron, zinc, copper, manganese, lead, and cadmium was determined in the kidney, liver, and abdominal muscle of the brown hare (Lepus europaeus), a species known for its bioindicative potential in environmental quality assessment. The animals assayed were divided into immature (in their first year of life; n=25) and adult (n=39). The hares were acquired in an area situated far away from major cities and direct impacts of industrial and transport pollution. The zinc content found in the assayed hare's muscles (25.9 microg/g w.w.) and that of manganese in the kidneys, liver, and muscles (2, 2.51 i 0.85 microg/g w.w., respectively) tended to be higher than those reported from the brown hare elsewhere in Europe. The content of cadmium (particularly in the kidneys) and lead proved substantial and close to those typical of the hare inhabiting industry-affected areas. Analysis of the data pooled for all the individuals showed Zn and Cd contents to increase with age in the kidneys, the liver Cd content increasing with age as well; on the other hand, the age-Cu content was negative. In addition, a number of significant correlations between the metals themselves were revealed, particularly with respect to Zn-Cd correlation in kidneys (r(s)=0.47), Fe-Cd, Zn-Cu, Mn-Zn, Mn-Cu, and Mn-Pb in the liver (r(s) of 0.42, 0.86, 0.72, 0.79, and 0.42, respectively), and Zn-Cu in the muscle (r(s)=0.56). The kidney cadmium content was higher by 81% in the adult than in the immature hare, the adult hare muscle copper content being lower by 15.5%.  相似文献   

17.
Whole blood from 33 healthy captive Asian elephants (Elephas maximus) was analyzed for 12 trace elements: aluminum, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium, cadmium, mercury, and lead for the purpose of estimating preliminary baseline population parameters for these minerals. Metals were quantified by inductively coupled plasma mass spectroscopy. Baseline ranges for all animals and for all trace elements were comparable to normal concentrations reported in other species. This is the first report of normal trace element levels in the blood of captive elephants.  相似文献   

18.
OBJECTIVE: To compare concentrations of trace minerals in the spinal cord of horses with equine motor neuron disease (EMND) with those of horses without neurologic disease (control horses). ANIMALS: 24 horses with EMND and 22 control horses. PROCEDURE: Spinal cord trace mineral concentrations in horses with EMND and control horses were analyzed by use of inductively coupled plasma atomic emission spectroscopy (calcium, phosphorus, sodium, potassium, magnesium, copper, iron, manganese, nickel, zinc, aluminum, cobalt, and chromium), atomic absorption spectrophotometry (lead and cadmium), flameless atomic absorption (mercury), and fluorometry (selenium). RESULTS: Copper concentration was significantly higher in the spinal cord of horses with EMND, compared with control horses; spinal cord concentrations of all other trace minerals were similar between groups. CONCLUSION AND CLINICAL RELEVANCE: Among spinal cord trace minerals investigated in the study, only copper concentrations were significantly different between horses with EMND and horses without neurologic disease, which suggests that copper may be involved in the pathogenesis of EMND. An hypothesis of oxidative injury in this disease is supported by the finding of increased copper concentrations in the spinal cord and by low vitamin E concentrations reported by other researchers.  相似文献   

19.
为选择草地施肥的肥料种类,减少施肥对乌蒙半细毛羊产业的影响,在威宁县凉水沟种羊场多年生人工草地开展施肥和放牧试验。 结果表明:凉水沟种羊场人工草地牧草铜含量相对较低,但仍高于乌蒙半细毛羊营养需要标准;施肥极显著增加牧草氮含量(P<0.01),各施肥处理之间没有明显差异。硫酸铵施肥显著增加牧草硫和锌含量(P<0.01),显著降低了牧草硒的含量(P<0.01)。放牧试验结束时,施硫酸铵草地的乌蒙半细毛羊血液中铜、铁和硒的含量极显著低于施硝酸铵草地和对照组(P<0.01), 动物血液锌和硫含量极显著高于硝酸铵施肥牧场和对照组(P<0.01)。硫酸铵施肥牧场的乌蒙半细毛羊血红蛋白、红细胞压积容量极显著低于硝酸铵施肥牧场和对照牧场(P<0.01),血清铜蓝蛋白含量、血清超氧化物歧化酶活力、血清谷胱甘肽过氧化物酶活力和血清过氧化氢酶等抗氧化酶的活力极显著低于硝酸铵施肥牧场和对照牧场(P<0.01),丙二醛的含量显著高于硝酸铵施肥牧场和对照牧场(P<0.01)。血液其他矿质元素和血液指标及血清生化值在2个施肥处理和对照之间均差异不显著。 因此得出结论,草地施肥的种类需要根据土壤矿物质分布和含量情况确定,铜含量低的牧场不适合硫酸铵施肥,硫酸铵施肥明显影响了乌蒙半细毛羊机体抗氧化系统功能。  相似文献   

20.
An experiment was conducted to investigate the temporal relationship of peripheral estrone (E1) concentration to changes in the size of the pelvic opening preceding and immediately following parturition. Twenty-six multiparous beef cows were observed from approximately 50 d prepartum to 7 d postpartum. Blood samples were collected at 7 d intervals preceding calving and at 1, 3 and 7 d following for E1 quantitation. Estimates of pelvic opening area were made at the time of blood sampling. Peripheral E1 concentrations were elevated beginning at approximately 25 d prepartum. Dams bearing male fetuses had greater (P less than 0.01) concentrations of E1 than did dams with female fetuses. Calf birth weight was correlated (r = 0.44, P less than 0.01) with E1 levels from 10 d prepartum through parturition. Postpartum pelvic area was greater for cows giving birth to male calves, with no significant differences for calf birth weights by sex. Correlations were observed between E1 concentration, and pelvic area measured from 50 d prepartum to 7 d postpartum (r = 0.26, P less than 0.01), 10 d prepartum to calving (r = 0.42, P less than 0.01), and from calving to 7 d postpartum (r = 0.33, P less than 0.01). Percentage increase in E1 concentration from 50 d prepartum to calving was significantly correlated (r = 0.75, P less than 0.01) to percentage pelvic area increase over the same period. A correlation also exists between maternal E1 concentrations and fetal sex and pelvic area. In summary, the increased estrogen concentrations in cows with male calves may facilitate pelvic spread, resulting in a larger pelvic opening.  相似文献   

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