Clinical efficacy on xerosis conjunctivitis of liver and kidney yin deficiency treated with SHI's acupuncture manipulation / 中国针灸

<p><b>OBJECTIVE</b>To compare the efficacy of the patients of xerosis conjunctivitis with liver and kidney yin deficiency among the combined therapy of acupuncture and Shi's manipulation, common acupuncture and artificial tears therapy.</p><p><b>METHODS</b>One hundred and eight patients were randomized into an acupuncture group, a SHI's manipulation group and an artificial tears group, 36 cases in each group. A total of 15 cases dropped out before the end of the study, including 4 cases in the acupuncture group, 6 cases in the SHI's manipulation group, and 5 cases in the artificial tears group. In the acupuncture group, acupuncture was applied to Jingming (BL 1) and Qiuhou (EX-HN 7) on the affected side, and the bilateral Sanyinjiao (SP 6) and Taixi (KI 3). The needles were retained for 20 min. In the SHI's manipulation group, on the basis of the treatment as the acupuncture group, Shuigou (GV26) was added and stimulated with SHI's acupuncture manipulation. In these two groups, acupuncture was given 3 times a week totally for 3 weeks. In the artificial tears group, sodium hyaluronate eye drops were used, 5 times a day, for 3 weeks totally. Separately, before treatment, at the moment after the 1st treatment and 3 weeks after treatment, the subjective symptom score, Schirmer I test, breakup time (BUT) of tear film were observed in each group.</p><p><b>RESULTS</b>(1) Subjective symptom score: at the moment after the 1st treatment and 3 weeks after treatment, the scores in each group were all reduced significantly as compared with those before treatment (all P < 0.05). At the moment after the 1st treatment, the score in the SHI's manipulation group and the artificial tears group was reduced apparently as compared with that in the acupuncture group (both P < 0.05). In 3 weeks of treatment, the score in the SHI's manipulation group was reduced apparently as compared with the acupuncture group and the artificial tears group (both P < 0.05). (2) For Schirmer I test, at the moment of the 1st treatment, the result in the SHI's manipulation group and the artificial tears group was improved significantly as compared with that before treatment (both P < 0.05). In 3 weeks of treatment, the result in the acupuncture group and the SHI's manipulation group group was improved significantly as compared with that before treatment (both P < 0.05). At the moment of the 1st treatment, the result in the artificial tears group was improved significantly as compared with the acupuncture group and the SHI's manipulation group (both P < 0.05). In 3 weeks of treatment, the result in the acupuncture group and the SHI's manipulation group was better than that in the artifi-cial tears group separately (both P < 0.05). (3) For BUT, the result in the acupuncture group and the SHI's manipulation group was prolonged significantly as compared with that before treatment and was prolonged apparently as compared with that in the artificial tears group (both P < 0.05) in 3 weeks of treatment.</p><p><b>CONCLUSION</b>The intervention of SHI's acupuncture manipulation relieves the subjective symptoms of xerosis conjunctivitis of liver and kidney yin deficiency and achieves the same efficacy as the common acupuncture and artificial tears treatment. It does not present the apparent advantages as the common acupuncture in the short term for promoting the tear secretion and tears film repair.</p>

Research progress on acupuncture therapy forxerophthalmia / 国际中医中药杂志

The clinical and experimental publish literatures of the traditional acupuncture treatment for xerophthalmia were review and selected, and the acupoints and outcomes index were analyzed. The clinical studies demonstrated that acupoints around eyes, head and face were mainly coordinated with Zangfu organs and meridians; and the experimental studies showed the effect of acupuncture work through stimulation of the lacrimal gland secretion, repairing lacrimal gland structure, inhibition of apoptosis to increase the flow of tears, extending the breakup time of lacrimal film, and relieving eye related symptoms.

Adsorption mechanism of furfural onto modified rice husk charcoals / 生物工程学报

To evaluate the absorptive characteristics of furfural onto biomass charcoals derived from rice husk pyrolysis, we studied the information of the structure and surface chemistry properties of the rice husk charcoals modified by thermal treatment under nitrogen and carbon dioxide flow and adsorption mechanism of furfural. The modified samples are labeled as RH-N2 and RH-CO2. Fresh rice husk charcoal sample (RH-450) and modified samples were characterized by elemental analysis, nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy and Boehm titration. The results show that fresh rice husk charcoal obtained at 450 degrees C had a large number of organic groups on its surface and poor pore structure. After the modification under nitrogen and carbon dioxide flow, oxygenic organics in rice husk charcoals decompose further, leading to the reduction of acidic functional groups on charcoals surface, and the increase of the pyrone structures of the basic groups. Meanwhile, pore structure was improved significantly and the surface area was increased, especially for the micropores. This resulted in the increase of π-π dispersion between the surfaces of rice husk charcoals and furfural molecular. With making comprehensive consideration of π-π dispersion and pore structure, the best removal efficiency of furfural was obtained by rice husk charcoal modified under carbon dioxide flow.

The analysis of influence factor on the recovery time of oculomotor nerve palsy after traumatic carotid-cavernous sinus fistula treated by balloon embolization / 中国医师进修杂志

Objective To investigate the influence factor of the recovery time of oculomotor nerve palsy (ONP) after traumatic carotid-cavernous sinus fistula (TCCF) treated by balloon embolization.Methods The clinical data of 76 patients with ONP after TCCF were retrospectively analyzed.All patients accepted intravascular balloon embolization treatment.Nonparametric test was applied to make single factor analysis of the influence factor of ONP recovery time,and linear regression analysis was applied to make multiple factor analysis.Results Seventy-six patients (100.0％) had a perfect occlusion for orificium fistulae after operation immediately,and 73 patients (96.1％) retained the internal carotid artery.Patients were followed up for 6-70 months,with an average of 34.2 months and no death cases.Seventy patients (92.1％) succeeded for embolization at the first time,and 6 patients (7.9％) relapsed after embolization for 6 weeks.The reasons of relapse was balloon leak,and no patients recurred after twice embolization.Seventy-six patients (100.0％) had recovery from ONP,and recovery time was (42.17 ± 32.39) d.The single factor analysis showed that the courses of diseases,fistula location,eye-tubercle location,degree of ONP,balloon quantity,state of internal carotid artery were the factor affecting the ONP recovery time (P ＜ 0.01 or ＜ 0.05).The linear regression analysis showed that the courses of the disease,fistula location,degree of ONP,balloon quantity were independent factor affecting the ONP recovery time (P ＜ 0.01).Conclusions Intravascular balloon embolization in the treatment of ONP after TCCF is safe and reliable.The courses of diseases,fistula location,degree of ONP and balloon quantity are the influencing factor of the oculomotor nerve functional recovery time,and should be given enough attention.

Research Advance on Moxa Smoke / 针灸推拿医学（英文版）

The purpose was to investigate the research achievements over the past two decades on moxa smoke produced in the process of moxibustion, in terms of its clinical studies, chemical compositions, safety assessment as well as the mild smoke or smoke-free moxibustion, for revealing the recent dynamic and developing orientation, and promoting its further application, succession and innovation.

Decreased Cyr61 under hypoxia induces extravillous trophoblasts apoptosis and preeclampsia / 华中科技大学学报（医学）（英德文版）

During placental development, oxygen environment is not only critical for trophoblasts migration and invasion, but also fundamental for appropriate placental perfusion. Cysteine-rich 61 (Cyr61, CCN1) was expressed in the extravillous trophoblasts (EVTs) and decreased in preeclampsia. Its regulatory properties in human first-trimester extravillous trophoblast cell line (TEV-1 cells) upon a low oxygen tension were investigated. The present study examined functional changes involved in adaptation to hypoxia of the TEV-1 cells, using cobalt chloride (CoCl(2)) as hypoxic mimic. It was found that hypoxia inhibited growth of TEV-1 cells and induced the increase of cell apoptosis (P<0.05). The Cyr61 expression in human EVTs was transcriptionally induced by CoCl(2). Inappropriate EVTs apoptosis has been implicated in the failure of trophoblasts to fully invade and modify the uterine environment and Cyr61 down-regulation, potentially leading to preeclampsia.

Clinical significance of leukocyte count and neutrophil count change on delayed traumatic intracranial hemorrhage patients / 中国医师进修杂志

Objective To investigate the clinical significance of leukocyte count and neutrophil count change on delayed traumatic intracranial hemorrhage(DTIH).Method Collected the peripheral venous blood of l 16 eases of DTIH and 123 cases of non-DTIH between June 2005 and Deeember 2007.Compared the leukocyte count and neutrophil count in all cases by different groups.Results The leukocyte count and neutrophil count of the DTIH patients whose first CT scan were negative[(13.35±6.72)×109/Land(12.78±6.43)×109/L,respectively]were significantly higher than those of head injury whose CT scan werenegative allthetime[(9.72±3.09)×109/Land(7.64±2.93)×109/L,respectively].The difference was significant (P＜0.01).There were no statistical significance of the leukocyte count and neutrophil count between DTIH patients and non-DTIH patients whose first CT scan were positive(P＞0.05).Conclusions As an independent guideline,the leukocyte count and neutrophil count may help the forepart diagnosis of DTIH patients whose first CT scan were negative.

Clinical Study on Anti-aging Action of Herbal Cake-partition Moxibustion / 针灸推拿医学（英文版）

Objective:To investigate the clinical efficacy and immunological mechanism of herbal cake-partitioned moxibustion for aging process.Method:The herbal cake-partitioned moxibustion was adopted for 223 cases to observe the aging scores before and after the treatment.Apart from that,the T-lymphocyte subsets and changes of IL-2 and 3-EP were also detected.Results:After treatment,the aging scores of 223 cases were all substantially reduced,along with an improvement of clinical symptoms,a strengthened cellular immune function,and an increase of total T-lymphocyte count.In addition,the CD4+/CD8+ ratio Was restored normal,the synthesis or secretion of IL-2 was increased and the β-EP(as the neurotransmitter to modulate immune function)was substantially improved.Conclusion:The aging process is closely associated with the immune function.Moxibustion Can modulate abnormal immune function and stabilize homeostasis and thus delay the aging process.

Endothelial nitric oxide synthase traffic inducer in the umbilical vessels of the patients with pre-eclampsia / 华中科技大学学报（医学）（英德文版）

The expression of endothelial nitric oxide synthase traffic inducer (NOSTRIN) was examined in the umbilical vessels of the patients with pre-eclampsia (PE) to explore its possible role in the pathogenesis of PE. The NOSTRIN mRNA in umbilical tissues was determined by RT-PCR. The eNOS activity in umbilical vessels was spectrophotometrically detected. NO2-/NO3-, the stable metabolic end products of NO, was measured by using nitrate reductase. RT-PCR showed that the expression level of NOSTRIN was significantly higher in women with PE than in the normal group (P<0.01). The activity of eNOS was significantly decreased in PE group [(12.83+/-3.61) U/mg] than in normal group [(21.72+/-3.83) U/mg] (P<0.01). The level of NO2-/NO3- in PE patients (27.53+/-7.48) micromol/mg was significantly lower than that of normal group (54.27+/-9.53) micromol/mg (P<0.01). The significant negative correlation existed between the expression of NOSTRIN and the activity of eNOS in umbilical vessels of women with PE (r=-0.58, P<0.01). It was concluded that the level of NOSTRIN expression was increased in umbilical vessel of women with PE, indicating that it may be involved in the pathogenesis of PE.

Effect of extracellular signal-regulated kinase pathway on nitric oxide release by human umbilical vein endothelial cell induced by placental growth factor-1 / 中华妇产科杂志

Objective To investigate the effect of extracellular signal-regulated kinase(ERK)pathway OH nitriC oxide(NO)release by human umbilical vein endothelial cell(HUVEC)induced by placental growth factor-1(PLGF-1).Methods During January to April 2006,50 samples of umbilical vein blood were collected from newborns delivered by cesarean section due to intrauterine distress and abnormal fetal position.HUVEC were primarily cultured by trypsin digestion.Then the following procedures were performed:(1)Cells were identified using the morphology andⅧfactor immunohistochemistry methods if the culture WaS satisfactory.(2)Cells were collected,and fms.1ike tyrosin kinase(Fit-1)protein and its mRNA expression were detected with immunoprints and RT-PCR methods.(3)The protein wag extractedafter cells were treated with PLGF-1(cells were collected before the treatment and 2.5,5.10,20 min after the treatment).The protein levels of ERK were determined by immunoprints.(4)The cells were cultured witll serum-free culture medim containing PLGF-1 only(culture media were collected 20,40,160,360.480.720 and 1440 rain after the treatment).The quantity of NO was detected with nitrate reductase metllod(5)The ceHs were cultured with serum.free culture medium containing PI)98059,the inhibitor of mitogen-activated protein kinase(MAPK)/MEK for 60 min Then the cells were cultured continuously with the serum-free culture medium containing PLGF-1 for 60 mira The culture media were coilected.The quantity of NO was detected by nitrate reductase method.The samples were divided into treatment group and control group.Control group was exactly the satne in treatment time,culture condition,and time to colleet the cells as the treatment group.except that it WaS not treated with PLGF-l or PD 98059.Resuits (1)By morphology and Ⅷ factor inununohistochemistry the cultured cells were identified to be HUVEC.(2)Fit-1mRNA and protein were expressed in HUVEC.(3)Expression of ERK protein started to increaSe at 2.5 min after treatment of HUVEC with PLGF-1,reaching the peak at 5 min,and decreased at 10 min.(4)Incomparison with the control group.NO started to increase at 20 rain after treatment of HUVEC with PLGF-lat 480 min(15.82±0.69)μmol/L Comparison between the two groups showed a significant difference (P<0.05).(5)ReleaSe of NO from the cells treated with PD98059 for 1 hour and PLGF WaS significantly inhibited,compared with the ceils treated with PLGF-1 only.Conclusion ERK pathways play an important role in N0 release bv HUVEC induced by PLGF.

Moxibustion on Telomerase Activity in Aging Rat / 针灸推拿医学（英文版）

Objective: To investigate the effect of moxibustion on telomerase activity and genes expression in tissues of senescent rats. Methods: Subacute aging rats model were established by injection with D-gal solution. Points Shenshu (BL 23) were treated with moxibustion in treatment group, contrasting with a model group and a normal group. Enzyme-Linked Immunosorbent Assays(ELISA) was used for the level oftelomerase activity in liver tissues, and In Situ Hybridization(ISH) was used for the condition of expression of telomerase genes in liver tissues. Results: The level of telomerase activity in the aging model group was obviously lower than that in normal control group (P＜0.01), the level in moxibustion group was obviously higher than that in model group(P＜0.05). In comparison with normal rats, the positive-expressed areas and photodensity of telomerase genes in aging model group were all significantly lower (P＜0.01,P＜0.01), and the positive-expressed areas in moxibustion group was significantly higher than that in model group (P＜0.01). Conclusions: Moxibustion could regulate telomerase activity of senile rats, hence delaying aging.

Expression of endothelial nitric oxide synthase traffic inducer in the placenta of pregnancy induced hypertension / 华中科技大学学报（医学）（英德文版）

The expression of endothelial nitric oxide synthase traffic inducer (NOSTRIN) in the placenta of the patients with pregnancy induced hypertension (PIH) was detected and its role in the pathogenesis of PIH was studied. The pathological changes in placental vessels were observed by HE staining. NO2-/NO3-, the stable metabolic end products of NO, was measured with nitrate reductase. The eNOS activity in placental tissues was assayed by spectrophotometry. Western blot analysis was applied to detect NOSTRIN expression. The incidence of thickening and fibronoid necrosis of placental vessels was significantly higher in women with PIH than in the normal group (P < 0.01). The levels of placental NO2-/NO3- in PIH patients (27.53 +/- 7.48 micromol/mg) were significantly lower than in normal group (54.27 +/- 9.53 micromol/mg, P < 0.01). The activity of eNOS was significantly decreased in PIH group (12.826 +/- 3.61 U/mg) as compared with that in normal group (21.72 +/- 3.83 U/mg, P < 0.01). Western blot analysis revealed that both groups expressed 58 kD NOSTRIN, but the protein level was significantly higher in women with PIH than in the normal group (P < 0.01). A significant negative correlation existed between the expression of NOSTRIN protein and the activity of eNOS in placental tissue of women with PIH (r = -0.57, P < 0.01). It was concluded that the level of NOSTRIN expression in placenta of women with PIH was increased, which may play an important role in the pathogenesis of PIH.

Analysis of placental growth factor in placentas of normal pregnant women and women with hypertensive disorders of pregnancy / 华中科技大学学报（医学）（英德文版）

To investigate the expressions of placental growth factor (PLGF) in placenta with hypertensive disorders of pregnancy (HDP), 45 women with HDP and 20 normally pregnant women were studied. Among 45 women with HDP, there were 23 cases of severe preeclampsia and one case of eclampsia. The location and level of PLGF proteins was determined by immunohistochemistry and Western blot. The expression of PLGF mRNA in placenta was assessed by reverse transcriptional-polymerase chain reaction (RT-PCR). The results showed that: (1) The distribution of PLGF in placenta with HDP was similar to normal one, which was mainly in the cytoplasm of villous syncytiotrophoblast and villous stroma; (2) The expression of PLGF protein was significantly decreased in placentas with mild and severe preeclampsia compared to the normal ones (0.3 +/- 0.4 vs 0.6 +/- 0.4, 0.2 +/- 0.5 vs 0.6 +/- 0.4, P 0.05); (3) The transcription levels of the PLGF mRNA in placentas with preeclampsia were significantly lower than in normal groups (3.33 +/- 0.39 vs 4.87 +/- 0.60, 1.97 +/- 0.29 vs 4.87 +/- 0.60, P < 0.01), and no differences were found between the gestational hypertension placenta and normal groups. These findings suggest that the abnormal expression of PLGF in placentas is related to the pathogenesis of HDP.

Analysis of Placental Growth Factor in Placentas of Normal Pregnant Women and Women with Hypertensive Disorders of Pregnancy / 华中科技大学学报（医学）（英德文版）

To investigate the expressions of placental growth factor (PLGF) in placenta with hypertensive disorders of pregnancy (HDP), 45 women with HDP and 20 normally pregnant women were studied. Among 45 women with HDP, there were 23 cases of severe preeclampsia and one case of eclampsia. The location and level of PLGF proteins was determined by immunohistochemistry and Western blot. The expression of PLGF mRNA in placenta was assessed by reverse transcriptionalpolymerase chain reaction (RT-PCR). The results showed that: (1) The distribution of PLGF in placenta with HDP was similar to normal one, which was mainly in the cytoplasm of villous syncytiotrophoblast and villous stroma; (2) The expression of PLGF protein was significantly decreased in placentas with mild and severe preeclampsia compared to the normal ones (0.3±0.4 vs 0.6± 0.4, 0.2±0.5 vs 0.6±0. 4, P＜0.01). There were no differences between the gestational hypertension placenta and normal one (0.5±0.6 vs 0.6±0.4, P＞0. 05); (3) The transcription levels of the PLGF mRNA in placentas with preeclampsia were significantly lower than in normal groups (3.33±0.39 vs4.87±0.60, 1.97±0.29 vs 4.87±0. 60, P＜0.01), and no differences were found between the gestational hypertension placenta and normal groups. These findings suggest that the abnormal expression of PLGF in placentas is related to the pathogenesis of HDP.

Expression of Endothelial Nitric Oxide Synthase Traffic Inducer in the Placenta of Pregnancy Induced Hypertension / 华中科技大学学报（医学）（英德文版）

The expression of endothelial nitric oxide synthase traffic inducer (NOSTRIN) in the placenta of the patients with pregnancy induced hypertension (PIH) was detected and its role in the pathogenesis of PIH was studied. The pathological changes in placental vessels were observed by HE staining. NO2-/NO3- , the stable metabolic end products of NO, was measured with nitrate reductase. The eNOS activity in placental tissues was assayed by spectrophotometry. Western blot analysis was applied to detect NOSTRIN expression. The incidence of thickening and fibronoid necrosis of placental vessels was significantly higher in women with PIH than in the normal group (P＜0.01). The levels of placental NO2-/NO3- in PIH patients (27.53±7.48 μmol/mg) were significantly lower than in normal group (54.27±9.53 μmol/mg, P＜0.01). The activity of eNOS was significantly decreased in PIH group (12. 826±3.61 U/mg) as compared with that in normal group (21. 72±3.83 U/mg, P＜0.01). Western blot analysis revealed that both groups expressed 58 kD NOSTRIN, but the protein level was significantly higher in women with PIH than in the normal group (P＜0.01). A significant negative correlation existed between the expression of NOSTRIN protein and the activity of eNOS in placental tissue of women with PIH (r=-0. 57, P＜0. 01). It was concluded that the level of NOSTRIN expression in placenta of women with PIH was increased, which may play an important role in the pathogenesis of PIH.

Expression of TGF-β1 in Placenta of the Patients with Pregnancy-induced Hypertension and Its relationship with Serum VCAM-1 / 华中科技大学学报（医学）（英德文版）

The expression of transforming growth factor-β1 (TGF-β1) in placental tissue of pregnancy-induced hypertension (PIH) and the relationship between the level of expression of TGF-β1 and the amount of vascular cell adhesion molecule-1 (VCAM-1) in serum was studied. Immunohistochemistry ABC was used to detect the expression and distribution of TGF-β1 in placental tissues in 40 PIH women and 20 normal pregnancy women. High resolution pathological image analysis system was used to determine the quality of TGF-β1. The VCAM-1 in serum was examined by enzyme linked immunoabsorbent assay (ELISA). The results showed that TGF-β1 could be express in syncytiotrophoblast. The levels of TGF-β1 expression in placental tissues of the patients with moderate and severe PIH were significantly higher (P＜0.05), while the serum VCAM-1 was significantly lower than in normal group (P＜0.01). There was a significant positive correlation between the expression of TGF-β1 in placental tissues and the serum VCAM-1 (r=0. 969, P＜0.01). It was concluded that the level of TGF-β1 expression in PIH was increased and was positively correlated with the amount of serum VCAM-1, indicating that they might be involved in the pathogenesis of PIH.

Expression of TGF-betal in placenta of the patients with pregnancy-induced hypertension and its relationship with serum VCAM-1 / 华中科技大学学报（医学）（英德文版）

The expression of transforming growth factor-beta1 (TGF-beta1) in placental tissue of pregnancy-induced hypertension (PIH) and the relationship between the level of expression of TGF-beta1 and the amount of vascular cell adhesion molecule-1 (VCAM-1) in serum was studied. Immunohistochemistry ABC was used to detect the expression and distribution of TGF-beta1 in placental tissues in 40 PIH women and 20 normal pregnancy women. High resolution pathological image analysis system was used to determine the quality of TGF-beta1. The VCAM-1 in serum was examined by enzyme linked immunoabsorbent assay (ELISA). The results showed that TGF-beta1 could be express in syncytiotrophoblast. The levels of TGF-beta1 expression in placental tissues of the patients with moderate and severe PIH were significantly higher (P < 0.05), while the serum VCAM-1 was significantly lower than in normal group (P < 0.01). There was a significant positive correlation between the expression of TGF-beta1 in placental tissues and the serum VCAM-1 (r = 0.969, P < 0.01). It was concluded that the level of TGF-beta1 expression in PIH was increased and was positively correlated with the amount of serum VCAM-1, indicating that they might be involved in the pathogenesis of PIH.

Noninvasive prenatal diagnosis of fetal sex by single-cell PEP-PCR method / 华中科技大学学报（医学）（英德文版）

A new method for noninvasive prenatal diagnosis of fetal sex was developed by using single-cell PEP-PCR techniques. Micromamipulation techniques were used to obtain single fetal cells from 273 maternal blood samples. The genome of single cells was preamplified by PEP and SRY genes were analyzed by PCR method. The SRY genes of 149 samples were detected by the new method among 153 samples carrying male fetus, while 119 out of 120 samples carrying female fetus were proved negative for SRY genes. The sensitivity and specificity of the new method were 97.39% and 99.17% respectively and the correct rate was 98.17%. The new method has the advantage of high sensitivity and specificity in noninvasive prenatal diagnosis of fetal sex and provides the basis of other researches such as sex-linked inherited diseases.

Noninvasive prenatal diagnosis of fetal sex by single-cell PEP-PCR method / 华中科技大学学报（医学）（英德文版）

A new method for noninvasive prenatal diagnosis of fetal sex was developed by using single-cell PEP-PCR techniques. Micromamipulation techniques were used to obtain single fetal cells from 273 maternal blood samples. The genome of single cells was preamplified by PEP and SRY genes were analyzed by PCR method. The SRY genes of 149 samples were detected by the new method among 153 samples carrying male fetus, while 119 out of 120 samples carrying female fetus were proved negative for SRY genes. The sensitivity and specificity of the new method were 97.39% and 99.17% respectively and the correct rate was 98.17%. The new method has the advantage of high sensitivity and specificity in noninvasive prenatal diagnosis of fetal sex and provides the basis of other researches such as sex-linked inherited diseases.