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S Kan

Publications and source records attributed to S Kan.

At least 109 records · Page 6Linked to original sources
PubMed1987

A UHF probe for NMR micro-imaging experiments.

A long solenoid is capable of producing, at least theoretically, a B1 field that is relatively more homogeneous than other known structures. This paper describes the design of a UHF probe incorporating a one-turn solenoid associated with a pair of parallel-plate transmission line feeders and presents a practical example used in a 360-MHz spectrometer for micro-imaging experiments. Numerical evaluation of the solenoid inductance using King's method for direct calculation of elliptic integrals is also included.

Equipment Design↗
PubMed1987

[Synthesis and metabolism of estriol conjugates].

As an indicator of fetal well being, the urinary estriol value is widely utilized. But the discrepancy between the results of NST and urinary estriol value has recently been pointed out. The estimation of plasma estriol is also recommended as a more reliable means of fetal assessment than that of urinary estriol. The purpose of the study is to clarify the patterns of estriol conjugates in maternal blood, retroplacental blood and cord blood, and further to elucidate the metabolism and secretion of each conjugate in organs and to determine the most useful conjugate as a source of fetal information. In normal pregnancy urine, estriol glucosiduronate is the dominant component of urinary estriol. In preeclampsia, the percentage of G decreased and that of G-S increased. In retroplacental blood, G-S is the main conjugate. On the other hand in cord blood, S is the dominant conjugate. The placental perfusion experiment revealed that the placenta hydrolyzed each conjugate to a free form and did not convert one conjugate to another. Periodical determination of plasma estriol conjugates in pregnant women revealed that the G-S fraction fluctuated most during parturition. The importance of liver as a possible site for estriol conjugation and the role of kidney in selective clearance of estriol conjugates are discussed.

Estriol↗
PubMed1986

Primary leptomeningeal ependymoblastoma. Case report.

Ependymoblastoma is considered to be a primitive malignant glioma with ependymal differentiation. This rare tumor occurs in very early life and shows rapid growth and a diffuse infiltration through the leptomeningeal space. The tumor cells are highly immature, with numerous mitoses and multilayered ependymal rosettes. The ependymoblastoma described in this report was found in a 17-year-old girl. In spite of detailed clinical and postmortem examinations, no definite primary site was identified in the neuraxis. The lesion spread predominantly throughout the leptomeningeal space. Histological analysis strongly suggested that this tumor originated from a heterotopic glial nest in the subarachnoid space. The absence of immunohistochemical neural tissue markers, glial fibrillary acidic protein, S-100 protein, neuron-specific enolase, and neurofilaments ruled out neuronal or glial differentiation. The authors were unable to find any previous report of primary leptomeningeal ependymoblastoma.

Adolescent↗
PubMed1986

[Two cases of recurrent gastrointestinal carcinoma treated with long-term THP].

Two patients with recurrent gastrointestinal carcinoma were treated with THP. Partial response was recognized in the local recurrent tumor of one patient and in liver metastasis of a second patient. THP was administered every three weeks at a dose of 60 mg per total body weight intravenously. The total dose of THP achieved was 720 mg in the first patient and 920 mg in the second. Despite the high dosage, neither cardiotoxicity nor alopecia was observed. These results suggest that the administration of THP may be efficacious and safe in the management of patients with recurrent gastrointestinal carcinoma.

Adenocarcinoma↗
PubMed1985

Anopheles flavirostris incriminated as a vector of malaria and Bancroftian filariasis in Banggi Island, Sabah, Malaysia.

Seven villages in Banggi Island, Sabah, Malaysia, were surveyed four times to evaluate the roles of local mosquitoes as vectors of malaria and Bancroftian filariasis. 11 species of Anopheles were found biting man. 53.9% of the anophelines caught were An. flavirostris, 27.1% An. balabacensis, 6% An. donaldi and 4.2% An. subpictus. Infective malaria sporozoites, probably of human origin, were found in two of 336 An. flavirostris and 12 of 308 An. balabacensis. Sporozoites, probably of a non-human Plasmodium, were found in An. umbrosus. Nine of 1001 An. flavirostris and four of 365 An. balabacensis harboured L2 or L3 filarial larvae identified as those of Wuchereria bancrofti. This is the first record of An. flavirostris as a natural vector of malaria and W. bancrofti in Sabah.

Anopheles↗
PubMed1985

Bancroftian filariasis and malaria in island and hinterland populations in Sabah, Malaysia.

An epidemiological survey of filariasis and malaria in Banggi Island and Upper Kinabatangan, Sabah, revealed microfilarial rates of 7.2% and 8.6% respectively and malaria prevalence of 9.7% and 16.9% respectively. Wuchereria bancrofti was a rural nocturnally periodic type with a periodicity index of 137.2 and average peak hour at 01.32 hrs; 9.2% of microfilaremic carriers as compared to 2.4% amicrofilaremic subjects had clinical filariasis. The Plasmodium falciparum: P. vivax: P. malariae ratios were 1:1:0.17 and 1.4:1:0.12 for Banggi and Upper Kinabatangan respectively. Anopheles flavirostris was incriminated as a new malaria vector in Banggi where the well-known primary malaria vector is An. balabacensis. The latter was also found for the first time to be a vector of rural W. bancrofti in Upper Kinabatangan. Experimental feeding also showed that L3 larvae of W. bancrofti were recovered at low rates from An. balabacensis. Aedes togoi appeared to be a suitable laboratory vector for W. bancrofti.

Adolescent↗
PubMed1985

[A case of multilocular renal cyst showing neoplastic features].

A 45-year-old woman was hospitalized with complaint of upper right abdominal pain. By serial examination, it was difficult to distinguish renal cyst from renal cancer. But, because of the frequency of the attacks of upper abdominal pain, nephrectomy was undertaken. The tumor measured 5 X 5 X 3 cm, was distinct from normal renal tissue, and consisted of a small cyst. Histologically, we diagnosed a multilocular renal cyst, and its lining cells showed small atypia and adenomatous proliferation. We concluded that this multilocular renal cyst showed neoplastic features.

Diagnosis, Differential↗
PubMed1985

[The usefulness of prolonged high dose delayed contrast computed tomography for the diagnosis of intracranial angiographically occult vascular malformations].

It is difficult to diagnose angiographically occult vascular malformations. When conventional CT (plain & contrast enhancement) can not demonstrate the lesions, it was impossible to diagnose in the past. We developed a new technique which enabled us to diagnose them. Materials and methods; Seven cases of spontaneous intracerebral hemorrhage, in which no abnormality was detected by repeated magnified serial angiography with subtraction technique and prolonged injection technique, were examined. In each case, conventional CT (plain & enhancement using 100 ml of 60% meglumine iothalamate) was performed first, which was immediately followed by the administration of 220 ml of 30% meglumine iothalamate for one hour. CT is taken at the end of the infusion. It, we call, is prolonged high dose delayed contrast CT: PHDD-CT. Total dose of iodine used in this technique was 59.22 gI (1.0 gI/kg body weight: BW). Results; Contrast enhancement effect of PHDD-CT was much better than that of conventional CT in all the cases. In three cases, the lesions were more clearly delineated in PHDD-CT. In four cases, only PHDD-CT could demonstrate the lesions. No side effect was observed. Comments; Several techniques for better enhancement have been reported, however they used large volume of contrast medium such as 1.5 or 2.0 gI/kg BW. Our technique can be performed with more security. Based on our good results, we recommend to use this PHDD-CT technique for the diagnosis of angiographically occult vascular malformations.

Adolescent↗
PubMed1983

Spinal cord size in syringomyelia: change with position on metrizamide myelography.

Change in the anteroposterior diameter of the cervical spinal cord was demonstrated on metrizamide myelography in 20 out of 40 cases of cervical syringomyelia. Twelve of these were normal-sized cords, four were small, and four enlarged. Comparable lateral cervical myelograms in the prone and supine positions were sufficient to show size change for normal-sized or small cords. Additional myelograms in the erect and Trendelenburg positions were necessary to show size change in enlarged cervical cords, especially with associated Chiari malformation. A localized change in cord size suggests syringomyelia. If the change in cord size is diffuse, then change less than 10% is not necessarily significant. In undiagnosed myelopathy, metrizamide myelography has the potential to detect unsuspected syringomyelia even when the cord is normal-sized or small. Myelographic study may also be useful as an adjunct to delayed computed tomographic studies.

Humans↗
PubMed1983

Balloon occlusion of a spontaneous fistula of the posterior inferior cerebellar artery. Case report.

A case is reported of a large spontaneous right posterior inferior cerebellar artery fistula in which the patient presented with a right cerebellopontine (CP) angle and right cerebellar syndrome. The patient was successfully treated by balloon occlusion at the fistula site. The location of the arteriovenous fistula, the mass effect of its enlarged draining veins on the cerebellum and CP angle structures, and the simple therapeutic endovascular occlusion with a detachable balloon make this case unique.

Adult↗
PubMed1983

Detachable calibrated-leak balloon for superselective angiography and embolization of dural arteriovenous malformations.

The authors describe a system comprising a small latex balloon attached to a Teflon catheter. The balloon has a distal calibrated leak which is used for intravascular embolization with isobutyl-2-cyanoacrylate. The balloon is easily detached after embolization. The combination of manual control of the balloon-catheter system, plus the ability of the balloon to navigate intra-arterially with the blood flow, makes this system suitable for superselective angiography and embolization of lesions supplied by the external carotid artery (ECA). This system avoids intimal dissection and concomitant arterial vasospasm when trying to negotiate steep distal curves of the ECA branches. Experimental embolization of several branches of the ECA in the dog, and clinical examples of treatment of dural arteriovenous malformations in three patients are described.

Adult↗