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[Extra-corporeal circulation. Experimental study. Comparative study of various oxygenators (author's transl)].

An experimental study of three different types of oxygenator was carried out in the dog during two hours extra corporeal circulation. The hemodynamic aspects and the characteristics of pulmonary elasticity that a previous study permitted us to choose as controls of the quality of extracorporeal perfusion, were studied. The results show that the pulmonary arterial resistances and the indices of pulmonary compliance do not recover during E.C.C. to their initial values, in the case of an E.C.C. using a bubble oxygenator. These results should be taken into consideration in the choice of the most suitable oxygenator.

Animals

Suprascapular entrapment neuropathy: a clinical, anatomical, and comparative study. Part 3: comparative study.

The suprascapular ligament seems to serve no defined function in the human. A comparative study was undertaken to elucidate its function. The suprascapular region was dissected in species representing seven existing primate families and six subprimate families. A striking dichotomy of pattern was observed. In the New World primates, the suprascapular ligament appeared to be continuous with the coracoclavicular ligament; the former merely served to increase the area of bony attachment of the coracoclavicular ligament. In the Old World monkeys and subprimate mammals, the suprascapular ligament was entirely absent. The human anatomy was comparable to that found in the New World primates. This dichotomy of pattern seems to be related to the function of the upper extremity in the different classes of mammals.

Animals

ICMSF methods studies. XII. Comparative study for the enumeration of Clostridium perfringens in feces.

As the second phase of an international comparative study for the enumeration of Clostridium perfringens, four methods were compared for "total" and spore counts of C. perfringens in fecal specimens: the SFP (Shahidi-Ferguson perfringens) agar (A), TSC (tryptose-sulfite-cycloserine) agar (B), SC (sulfite-cycloserine) agar (C), and neomycin blood agar (D) methods. In both the total and spore count procedures, the confirmed C. perfringens counts in method D were lower than in methods A, B, and C. Little differences among methods were found in the percentages of presumptive colonies confirmed as C. perfringens. The nonspecific counts in methods A and D were generally greater than in B and C, but nonspecific microorganisms did not interfere in the enumeration of C. perfringens spores by any of the four methods. In overall performance, methods B and C were superior to A and D. The mean C. perfringens spore count was only 0.17 log lower than the mean total count. Spore counts alone are, therefore, adequate in investigations of C. perfringens outbreaks.

Bacteriological Techniques

ICMSF methods studies. VIII. Comparative study for the enumeration of Clostridium perfringens in foods.

Four methods were compared in an international comparative study for the enumeration of Clostridium perfringens: the SFP (Shahidi-Ferguson perfringens) agar (A), TSC (tryptose-sulfite-cycloserin) agar (B), SC (sulfite-cycloserine) agar (C), and neomycin blood agar (D) methods. The confirmed C. perfringens counts were slightly lower for D than for A-C. The percentages of presumptive colonies confirmed as C. perfringens were essentially the same in each method. The relative numbers of nonspecific colonies were the lowest in C, followed by B, D, and A. The methods were also compared for simplicity and for aspects associated with the recognition and selection of presumptive colonies.

Agar

Platelet adhesiveness and cancer cell stickiness: a comparative study.

Comparing platelet adhesiveness and cancer cell stickiness under the conditions of the so-called Fibre test showed that: 1. Platelets aggregate in the first few seconds only, whereas Yoshida sarcoma cells accumulate continuously. 2. Platelets show a characteristic velocity profile. Platelet adhesiveness shows a maximum at a velocity of 7 cm/sec. Yoshida sarcoma cells adhere better at low flow velocity. 3. An experimentally induced electric current (streaming electric current) of ca. 40 mV augments platelet adhesiveness to twice the basal value, whereas Yoshida sarcoma cells remain uninfluenced by the current. These results suggest an interaction between platelets and vessel wall, whereas Yoshida sarcoma cells adhere passively.

Animals

Portal vein blood flow measurements using pulsed Doppler and electromagnetic flowmetry in dogs: a comparative study.

Comparative measurements of portal vein blood flow were performed at laparatomy in anesthetized dogs using either a pulsed Doppler echo system or electromagnetic flowmeters. Three hundred four simultaneous determinations were obtained under baseline conditions and during vasopressin and glucagon infusions. In each dog, serial triplicate measurements were taken within 10 min of each other. In all the cases, flow changes induced by vasoactive drugs followed the same direction regardless of the method used. Portal vein blood flow as measured by electromagnetic flowmetry ranged from 85 to 1570 ml/min. Portal vein blood flow values obtained with Doppler and electromagnetic flowmeters were not significantly different (609 +/- 335 vs. 600 +/- 370 ml/min; p = NS) and were highly correlated (r = 0.918, p less than 0.001). The difference between values obtained by the two techniques was -3 +/- 159 ml/min or -1.0% +/- 21.2% (mean +/- SD). This difference was not influenced by the portal vein diameter but increased slightly as a function of the angle of insonation. When considering the mean of triplicate measurements, we also found a highly significant correlation between data obtained by the two techniques (r = 0.934, p less than 0.001; n = 63). The mean difference was 11 ml/min, but limits of agreement between these methods were -267 and +239 ml/min. This relative discrepancy was explained by a coefficient of variation higher in Doppler measurements than in electromagnetic measurements (10.9% vs. 5.9%). These data demonstrate that under our experimental conditions, Doppler flowmetry is probably not an ideal method to measure absolute portal vein blood flow values, and that more sophisticated equipment is needed to improve its reproducibility and accuracy. In humans, however, this method might be a useful tool to assess the direction of portal flow changes in the same individual.

Animals

A study to compare oral sumatriptan with oral aspirin plus oral metoclopramide in the acute treatment of migraine. The Oral Sumatriptan and Aspirin plus Metoclopramide Comparative Study Group.

In a double-blind, placebo-controlled study, the efficacy, safety and tolerability of 100 mg oral sumatriptan, given as a dispersible tablet, was compared with that of 900 mg oral aspirin plus 10 mg oral metoclopramide in the acute treatment of migraine. A total of 358 patients treated up to three migraine attacks within 3 months, recording clinical information on a diary card. In attack 1, headache relief after 2 h, defined as a reduction in severity from severe or moderate pain to mild or no pain, was recorded in 56% (74/133) of patients who took sumatriptan and 45% (62/138) of patients who took aspirin plus metoclopramide (p = 0.078). This analysis of the primary efficacy end point was not statistically significant. However, for attacks 2 and 3 (secondary end points), headache relief was achieved in 58 versus 36% of patients (p = 0.001) and 65 versus 34% of patients (p less than 0.001), respectively. Relief from nausea, vomiting, photophobia and phonophobia was similar in both treatment groups. Rescue medication was required by fewer patients treated with sumatriptan than by those who received aspirin plus metoclopramide (attack 1, 34 versus 56%, p less than 0.001; attack 2, 32 versus 51%, p = 0.001, and attack 3, 35 versus 54%, p = 0.001). Sumatriptan also produced a faster improvement and resolution of migraine attacks. Comparing the sumatriptan and aspirin plus metoclopramide treatment groups, complete resolution of the attack occurred within 6 h in 32 versus 19% (attack 1), 35 versus 23% (attack 2) and 32 versus 20% of patients (attack 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral

International comparative study of childhood malignancy comparative study of pediatric malignancy between Kurume and Karachi (K-K Project 1991).

UNLABELLED: A study was undertaken to compare Pediatric Malignancy at Kurume (Japan) and Karachi (Pakistan) with reference to international data collected over the years, in order to identify essential differences between developed and developing conditions and factors influencing the etio-pathogenesis of pediatric cancer. The study was retrospective encompassing all types of cancer in children over a period of three years i-e 1988-1990. Essential factors related to present study were: 1. POPULATION: The population of Karachi is about 10 million while that of Kurume is only half a million. 2. Socio-economic conditions: The average socio-economic condition of people in Karachi is poor while in Kurume it appears to be good. 3. Educational status: Only 25% people in Karachi are educated beyond middle class while Kurume reveals a 100% education up to high school level. 4. Environmental conditions: The environmental conditions of Kurume and surrounding areas are very clean and free from pollution, sewage problems and traffic hazards. Karachi and its surroundings on the other hand pose very serious air and water industries! It was concluded that whereas genetic predisposition predominates, the environmental conditions, educational and socio-economic status of a society immensely influence the pattern and trends of pediatric carcinogenesis.

Adolescent

A comparative study of the ease of removal of intrauterine contraceptive devices.

This study compares the rates of easy and difficult removals of various types of IUDs. Eight-hundred-sixteen IUDs were removed in Auckland Family Planning Clinics in an 8-month period. Nearly 80% were the standard Multiload Copper 250. Eight-eight percent of all IUDs were easy to remove with another 7% requiring a hard pull. Of the remaining 5%, 3.5% required simple intracervical exploration, 1% required intrauterine exploration and 0.5% were referred to hospital. When compared with the standard Multiload, no IUD was statistically easier and only the Mini-Copper 7 was harder to remove at the 5% level of significance.

Family Planning Services

Male or female sterilization: a comparative study.

The study compares 709 males and 546 females recruited from a well-defined geographic area and sterilized during a 5-year period at the same hospital. Medical records were reviewed and questionnaires sent out. Widespread satisfaction with the sterilization was found. The sterilized women had experienced contraceptive side effects and failures more often than the men. Only 70% of the laparoscopic sterilizations could be carried out during a 1-day admission, 25% of the women complained about long-term sequelae, and there were 1% failures. The vasectomies were carried out on an outpatient basis, there were few postoperative symptoms, and 0.5% failures were recorded. Female sterilization was at least four times as expensive as vasectomy. It is concluded that vasectomy is generally to be preferred to female sterilization, and that the preoperative guidance should involve both man and wife.

Adult

[A multicenter comparative study in patients with liver metastasis to compare tegafur in new forms with existing drugs. SF-RC.SF-SP Comparative Study Group].

A multicenter comparative study was carried out in 101 patients with liver metastasis to compare tegafur in a new oral form (Sunfural S) and tegafur in a new soft-capsule suppository form (Sunfural Rectal Capsules) with existing drugs. Sunfural S showed a tendency toward high plasma and tissue levels as compared to existing drugs, and clinically, Sunfural S produced survival times that surpassed those of existing drugs. Liver metastasis at the present time has few effective treatments, but we expect that anticancer effects will be obtained through the administration of new drugs with improved bioavailability.

Administration, Oral

Comparative study of luting agents with composite resin cores.

This study compared bond strengths of zinc phosphate and polycarboxylate cements in cementing cast gold crowns to composite resin cores. The study also compared the effect of thermocycling on the bond strengths in tension of the two cements under varied storage and thermocycling conditions. Sixty standard cores were made from composite resin material. Gold alloy crowns were cast for each core and cemented with zinc phosphate or polycarboxylate cement. The samples were stored for 1 day or 1 month and then cycled with 60-second dwell times between 5 degrees C and 55 degrees C distilled water baths for 5, 100, or 1000 cycles. The controls were stored for the same periods and were not cycled. Overall comparison of both storage periods and all cycled and noncycled groups revealed that zinc phosphate cement had significantly higher bond strengths than polycarboxylate cement. Increasing the storage time before cycling significantly increased the bond strengths for both cements. There was no difference between any of the cycle periods or the noncycled controls for either cement.

Composite Resins

A home-monitoring program for parents of premature infants: a comparative study of the psychological effects.

Controversy characterizes the reported effects of home monitoring on parental well-being. However, past studies were largely retrospective and uncontrolled. The present prospective study compared the psychological effects of a home-monitoring program on 40 parents of first-born premature infants with its effect on 30 parents of similar prematures and 32 parents of normal full-term infants. Home interviews conducted within 2 weeks after discharge were complemented with standardized instruments measuring psychological symptoms, life events, and family satisfaction. All of the parents of monitored infants participated in an educational and support program and did not report increased depression, anxiety, or other psychological symptoms, compared with parents of nonmonitored premature or full-term infants. These monitoring parents reported significantly more support than did other parent groups (p = 0.005). Surprisingly, parents of non-monitored prematures reported higher psychological symptoms than those in either of the other study groups. Results suggest that a professional educational and support program protects the psychological well-being of parents of premature infants.

Adult