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81.
周良才  李锋  张碧玉  覃良  蒋汉明   《广西植物》1987,(2):149-157
长滩果系罗汉果最佳品种。原产区分布于永福和临桂县交界400—600米山区,但不适应于低丘陵和平原地区,因而不能在低丘陵和平原地区推广。为了解决这个问题。采用了(1)选择湿润和半阴的生长环境;(2)采用适应性强的砧木;(3)促成栽培;(4)加强秋旱期的科学管理等措施并取得成功,试验结果表明长滩果产量和品质达到或略超过原产区水平。  相似文献   
82.
Historically, restoration of hand function following multiple digital amputation has been unsatisfactory. The evolution of digital reconstruction with toe transfer has enabled surgeons to reestablish prehension in these severely injured hands. A 4-year experience with 26 consecutive combined second and third toe transfers to replace missing adjacent fingers was reviewed in order to delineate the indications and technical considerations and to emphasize prevention of donor-site complications. Combined second and third toe transfer is reserved for adjacent finger amputations proximal to the digital web space with remaining fingers no longer than the small finger. Radial amputations are replaced with contralateral combined toe units, while ipsilateral toes are more ideal for ulnar amputations. Limited dorsal and plantar skin flaps extending only to the midpoint of the first and third digital web spaces allow for direct donor-site closure and uncomplicated healing. Maintenance of the plantar metatarsal arch by avoiding metatarsal shaft osteotomies or bone grafting-shortened metatarsals eliminates potential gait disturbances. When properly applied in selected patients, this single-stage microsurgical procedure can restore prehensile function, improve the appearance of the hand with multiple digital amputations, and preserve near-normal donor-foot function.  相似文献   
83.
The groin flap is a reliable and well-established reconstructive option for pedicled or free-tissue transfer. Concern regarding its variable vascular origin and caliber has limited its use. To overcome this, a simplified guideline based on the transverse diameter of the patient's index and long fingers at the distal interphalangeal level has been developed. Thus "rule of two finger widths" positions the origin of the vascular pedicle from the femoral vessels two finger widths below the inguinal ligament, the upper flap border two finger widths above the inguinal ligament, the lower flap border two finger widths below the vascular origin, and both parallel to the flap axis, which lies along a line from the vascular origin to the anterosuperior iliac spine. This new groin flap design provides the necessary guidelines for vascular identification, accommodates pediatric and adult stature, and ensures primary donor-site closure if flap dimensions are within the prescribed boundaries. In addition, a new sartorius-cutaneous groin flap is presented. This combines the cutaneous groin flap with the proximal sartorius muscle (up to 15 cm), which is supplied by the deep vessels of the superficial circumflex iliac system. The sartorius-cutaneous groin flap further emphasizes the concept of single-pedicle compound or combined flaps and additionally enhances the extensive reconstructive versatility of previously described groin flaps. Over 200 pedicled and free groin flaps have been performed according to the "rule of two finger widths" over the past 5 years. There have been no complications related to flap design, such as difficulty with flap elevation, marginal necrosis, or donor-site closure.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
84.
In this paper, we report the effects of laser microirradiation of prophase nucleoli and mitotic chromosomes in cells of female rat kangaroo kidney epithelial cell line PTK1. When the laser power delivered to sample surface was 90-190 mW, irradiation of one of the two nucleoli in the prophase cell did not inhibit the mitotic progress, but resulted in the loss of the irradiated nucleolus in daughter cells. When the laser power was increased to 360-420 mW, either irradiation of the nucleolus or chromosome in midprophase caused a blockage of mitosis at terminal midprophase. The irradiated cells returned morphologically to early prophase. No mitotic reversion occurred in the case of irradiation of chromosomes at late prophase, prometaphase, metaphase, and anaphase. Irradiation of the cytoplasm in prophase cells caused a 50-70 min mitotic delay at prophase. However, the irradiated cells underwent successive mitotic divisions. The mechanism of laser-induced mitotic prophase reversion is discussed.  相似文献   
85.
贵州两栖动物区系及地理区划的初步研究   总被引:6,自引:0,他引:6  
魏刚  陈服官 《动物学研究》1989,10(3):241-249
本文报道贵州省两栖动物63种,其中省新纪录2种,即阔褶蛙和锯腿树蛙。将贵州划分为黔西高原中山、黔北中山峡谷、黔中山原丘陵、黔东南低山丘陵盆地和黔南低山河谷五个动物地理省。认为黔南低山河谷省属于向华南区过渡的华中地带。讨论了各动物地理省的地貌、气候、两栖动物区系特征及地理替代种类。分析了各动物地理省两栖动物区系的相似性及数量关系。  相似文献   
86.
87.
The voltage-sensitive calcium channel in cultured chick neural retina cells was characterized by the actions of the enantiomers of Bay K 8644 and 202-791 and other 1,4-dihydropyridines. These cells showed time- and voltage-dependent Ca2+ uptake that was stimulated by K+ depolarization and blocked by the inorganic calcium channel blockers Cd2+ and Co2+. A small fraction only (15% maximum) of the uptake was inactivated by predepolarization of the cells with 80 mM K+. Ca2+ uptake was sensitive to the 1,4-dihydropyridine calcium channel antagonists and activators. (S)-Bay K 8644 and (S)-202-791 stimulated the Ca2+ uptake, and (R)-Bay K 8644 and (R)-202-791 as well as nitrendipine and PN 200-110 inhibited Ca2+ uptake stimulated by K+ depolarization or channel activators. The K+ depolarization-stimulated uptake was inhibited by 90%, but the activator-stimulated uptake was completely blocked by the 1,4-dihydropyridine antagonists. The potencies of these agents as inhibitors of Ca2+ uptake were significantly lower than the binding affinities in membrane preparations from the same cells or their binding and pharmacologic affinities in vascular smooth muscle. K+ depolarization or (S)-Bay K 8644 induced 45Ca2+ uptake was not observed in a glial cell culture. [3H]Nitrendipine and [3H]PN 200-110 bound to membrane preparations of the cells consistent with the presence of a single type of high affinity binding site.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
Polyclonal antibodies against rabbit skeletal muscle phosphatases C-I and C-II were raised in goats and in mice. The goat polyclonal antibodies to phosphatases C-I and C-II were examined for their ability to immunoblot the purified enzymes and crude rabbit muscle extracts. In preparations of phosphatases C-I and C-II that were apparently homogeneous, the expected ca. 35- to 38-kDa polypeptides were immunoblotted, but, in addition, immunoblotting of a 67-kDa polypeptide was observed. Both the antisera blotted only the 67-kDa polypeptide in crude rabbit muscle extracts and not the expected 35- to 38-kDa polypeptides. These findings are qualitatively similar to those reported previously (D.L. Brautigan et al. (1985) J. Biol. Chem. 260, 4295-4305) where immunoblotting experiments with a sheep antisera to phosphatase C-I indicated that the ca. 35-kDa polypeptide originates from a 70-kDa precursor. On further investigation, it was found that our antisera were strongly immunoreactive to rabbit serum albumin. The antisera blotted purified rabbit albumin, but not bovine serum albumin. After passage through a rabbit albumin-Sepharose column, the antisera lost immunoreactivity to rabbit albumin, and no longer blotted the ca. 70-kDa band in muscle extracts or in purified enzyme preparations. These findings show that the phosphatase preparations contained traces of albumin which produced a strong antigenic reaction. Production of antisera in BALB/c mice produced similar results; i.e., an antibody to the low-molecular-weight phosphatases was produced that was also a strong antibody to rabbit albumin. This antibody could be removed by affinity adsoption on rabbit albumin-Sepharose columns. In addition, the antibodies to phosphatase C-I displayed no cross-reactivity to phosphatase C-II, while antibodies to C-II showed no cross-reactivity to phosphatase C-I by immunoblotting methods.  相似文献   
89.
A novel neuropeptide which stimulates adenylate cyclase in rat anterior pituitary cell cultures was isolated from ovine hypothalamic tissues. Its amino acid sequence was revealed as: His-Ser-Asp-Gly-Ile-Phe-Thr-Asp-Ser-Tyr-Ser-Arg-Tyr-Arg-Lys-Gln- Met-Ala- Val-Lys-Lys-Tyr-Leu-Ala-Ala-Val-Leu-Gly-Lys-Arg-Tyr-Lys-Gln-Arg-Val-Lys-Asn-Lys - NH2. The N-terminal sequence shows 68% homology with vasoactive intestinal polypeptide (VIP) but its adenylate cyclase stimulating activity was at least 1000 times greater than that of VIP. It increased release of growth hormone (GH), prolactin (PRL), corticotropin (ACTH) and luteinizing hormone (LH) from superfused rat pituitary cells at as small a dose as 10(-10)M (GH, PRL, ACTH) or 10(-9)M (LH). Whether these hypophysiotropic effects are the primary actions of the peptide or what physiological action in the pituitary is linked with the stimulation of adenylate cyclase by this peptide remains to be determined.  相似文献   
90.
Previous reports have suggested that a 65 kDa membrane protein, termed homologous restriction factor (HRF), in addition to protecting erythrocytes (E) against lysis by homologous complement (C), may also be involved in protecting cytolytic lymphocytes against lysis mediated by a pore-forming protein (PFP/perforin), one of their own lytic mediators. Here, we used HRF-deficient type III E of patients with paroxysmal nocturnal hemoglobinuria (PNH) to study their susceptibility to lysis mediated by homologous C and perforin, and compared it with lysis of HRF-bearing control or PNH type I E. We show that type III E of PNH patients are indeed more susceptible to lysis mediated by homologous C than control or type I E, but they are as susceptible to perforin-mediated lysis as type I E. In addition, all human E (type I or III) tested here are equally susceptible to lysis mediated by either human (homologous) or murine (heterologous) perforin. By immunoblot analysis, we confirm that type III E, in contrast to type I E, were deficient in the 65 kDa HRF. These results support the notion that homologous species restriction is seen in the C- but not in the lymphocyte perforin-system and argue against an active participation of HRF in protecting cells from perforin-mediated lysis.  相似文献   
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