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51.
52.
A technique for reconstruction of the medial patellofemoral ligament   总被引:9,自引:0,他引:9  
Additional medial patellofemoral ligament reconstruction was performed successfully on six consecutive patients with recurrent dislocation of the patella because of residual patellar instability after medial transfer of the tibial tubercle. A technique for medial patellofemoral ligament reconstruction is described, and complications and postoperative management are discussed. The reconstruction was performed using a double strand hamstring tendon graft in five patients and iliotibial allograft in one. Good stabilization of the patella was achieved in all six patients, resulting in improved confidence in higher levels of activity. The satisfactory outcome of additional medial patellofemoral ligament reconstruction suggests the possibility that the procedure may be part of the optional procedure in proximal realignment for recurrent dislocation of the patella.  相似文献   
53.

Purpose

It is well established that hyperprolactinemia, most typically seen in prolactinoma patients, causes hypogonadism and impotence. There seem to be a good possibility that hyperprolactinemia causes impotence, at least partially via some intrinsic property of prolactin (PRL), rather than through its suppressive effects on the hypothalamic-pituitary-gonadal testosterone dynamics. In the present investigation, we used an in vitro canine model to attempt to clarify whether direct action of PRL on the corpus cavernosum penis may lead to erectile insufficiency. Growth hormone (GH) and placental lactogen (PL), both having close structural and functional homologies to PRL, were also studied.

Materials and Methods

Isometric tension measurement with cavernous strips was performed in the presence or absence of 10 sup -5 to 10 sup -9 M. PRL, GH, or PL in the perfusion medium. The tension change induced by the test substances was normalized relative to that induced by 120 mEq KCl.

Results

Both PRL and GH produced dose-related elevations (p less than 0.01) of the cavernous tension, whereas PL and thiol-cleaved PRL in comparable doses were without effect (p greater than 0.05). When the tension rise produced by 120 mEq KCl was taken as 100 percent, the maximum contractions produced by PRL and GH were 80 percent and 110 percent. The minimum effective concentration was 10 sup -8 to 10 sup -7 M. for both PRL and GH. Pretreatment with indomethacin (10 sup -5 M.), but not tetrodotoxin (10 sup -5 M.), partially suppressed (p less than 0.05) the effects of PRL.

Conclusion

These results suggest that PRL and GH directly and specifically produced contraction of the corpus cavernosum penis, resulting in erectile insufficiency, and that the effect of PRL is partially mediated by prostaglandin.  相似文献   
54.
55.
Matsui H, Iitsuka Y, Seki K, Sekiya S. Etoposide (VP-16) as first-line,single agent chemotherapeutic drug in low-risk gestational trophoblasticdisease. Int J Gynecol Cancer 1997; 7: 400–404.
We reviewed the records of 73 patients with low-risk gestationaltrophoblastic disease (GTD) treated with etoposide from 1986 to 1995 at ChibaUniversity. All patients received courses of etoposide every 10 to 14 days until their human chorionicgonadotropin (hCG) concentrations had reached <1 mIU/ml or drug resistanceand/or unacceptable toxicityoccurred. Fifty-one patients (69.9%) were treated with chemotherapyalone and 22 patients (30.1%) also underwent planned hysterectomy.
Sixty-seven patients (92%) achieved a primary remission, while sixpatients (8%) required a change in drugs due to drug resistance (4patients, 5%) or toxicity (2patients, 3%). All 73 patients achieved complete remission. However, onepatient (1.4%) relapsed later.
We have demonstrated that etoposide is one of the most effective drugsagainst GTD and that the short-term toxicity is, except for alopecia,relatively mild and acceptable.Patients should, however, be informed of the possibilities of secondarymalignancies and followed-up cautiously.  相似文献   
56.
Primary carcinoma of the fallopian tube is extremely rare and the preoperative diagnosis is often misdiagnosed as an ovarian carcinoma. We report a patient with primary carcinoma of the fallopian tube, strongly suspected preoperatively on the basis of characteristic clinical symptoms, elevated CA125 levels, and transvaginal sonography, computed tomography, and magnetic resonance imaging findings. The histology of fallopian tube carcinoma was demonstrated as transitional cell carcinoma. Extensive review of the literature showed that our case seemed to be the 14th case of primary transitional cell carcinoma of the fallopian tube.  相似文献   
57.
The modifying effects of quinacrine administration during the post-initiation phase of carcinogenesis were investigated in hamsters treated with N -nitrosobis(2-oxopropyl)amine (BOP). Female Syrian hamsters were given three weekly s.c. injections of BOP at a dose of 10 mg/kg and then 300 or 100 ppm quinacrine in their diet for 37 weeks. Additional groups of animals received the BOP injection alone, or only the 300 ppm quinacrine treatment as BOP-negative controls. At week 40 of the experiment, all surviving animals were killed and development of proliferative lesions was assessed histopathologically. The multiplicity of pancreatic adenocarcinomas and dysplastic lesions per hamster was significantly higher ( P <0.01 and P <0.05) in the BOP/Q100 group (1.92 and 1.78) than in the BOP-alone group (1.07 and 0.79). The incidence of hepatocellular adenomas plus carcinomas was also significantly elevated ( P <0.05) in the BOP/Q300 and BOP/Q100 groups. In contrast, the multiplicity of lung adenomas plus adenocarcinomas was significantly decreased ( P <0.05) by the Q300 treatment. Neither the incidence nor the multiplicity of renal cell tumors (adenomas and carcinomas) or nephroblastomas significantly differed between the BOP-treated groups. Electron microscopic examination revealed an abundance of myeloid lamellar bodies filling the cytoplasm of hepatocytes and pancreatic ductular and acinar cells, and epithelial cells of the gallbladder in the quinacrine-treated animals, the degree being dose-dependent. Our results indicate that quinacrine enhances pancreatic and hepatic carcinogenesis in hamsters induced by BOP.  相似文献   
58.
59.
The modifying potential on tumor development of arachidonate-enriched triglyceride oil (ARA-oil) containing approximately 40% arachidonic acid was investigated in a medium-term multi-organ carcinogenesis bioassay using male and female F344 rats. The animals were sequentially given five carcinogens with different target sites in the first 4 weeks, and then administered ARA-oil for 24 weeks at dietary levels of 0% (control), 1.25%, 2.5% or 5.0%. No statistically significant differences in incidences and multiplicities of hyperplastic and neoplastic lesions were showed in the large intestine in either sex. In the liver, kidney, and lung in both sexes, and the mammary gland and uterus in females, tumor promoting potential was not evident with ARA-oil treatment. ARA-oil did not affect the quantitative data for glutathione S-transferase placental form positive foci of the liver. Increased induction of hyperplastic or neoplastic lesions in the urinary bladder and thyroid in ARA-oil-treated groups was without dose dependence. In addition, a second experiment with ARA-oil only administration for 8-week revealed no effects on cellular proliferation in the urinary bladder or thyroid in either sex. These results indicate that ARA-oil has no tumor promoting potential in any organs or tissues initiated with the five carcinogens applied in the present study.  相似文献   
60.
Combination of amino acids reduces pigmentation in B16F0 melanoma cells   总被引:1,自引:0,他引:1  
Amino acids, the building blocks of proteins, play significant roles in numerous physiological events in mammals. As the effects of amino acids on melanogenesis have yet to be demonstrated, the present study was conducted to identify whether amino acids, in particular alanine, glycine, isoleucine and leucine, influence melanogenesis in B16F0 melanoma cells. Glycine and L-isoleucine, but not D-isoleucine, reduced melanogenesis in a concentration-dependent manner without any morphological changes in B16F0 melanoma cells. L-Alanine and L-leucine, but not D-alanine and D-leucine, also reduced melanogenesis without any morphological changes in B16F0 melanoma cells. However these amino acids did not show a concentration-dependency. Combination of L-alanine and the other amino acids, particularly 4 amino acids combination, had an additive effect on the inhibition of melanogenesis compared with single treatment of L-alanine. None of the amino acids affected the activity of tyrosinase, a key enzyme in melanogenesis. These results suggest that L-alanine, glycine, L-isoleucine and L-leucine, but not the D-form amino acids, have a hypopigmenting effect in B16F0 melanoma cells, and that these effects are not due to the inhibition of tyrosinase activity. Combination of these 4 amino acids had the additive effect on hypopigmentation that was as similar as that of kojic acid.  相似文献   
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