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101.
Microscopic cysts in the permanent cortices of adrenal glands were studied in a series of 274 infants, some of whom had been stillborn and none of whom were more than 12 months old. After correction for length of gestation, there were no significant relationships between the occurence and number of microcysts and various maternal, placental, and perinatal diseases. A significant direct correlation was demonstrated statistically with shorter gestational period and shorter survival time after birth. We concluded that the adrenal microcysts are either a developmental feature or the result of a greater susceptibility to stress in the fetus and newborn than in older infants.  相似文献   
102.
Data on prenatal, labor and delivery, and postnatal medication exposure to neonates were collected. During an 11-week period, 100 neonates consecutively admitted to a hospital were studied. The pharmacist obtained a social and medication history from the mothers and reviewed maternal anesthesia records and the charts of the neonates. Fifteen definite and possible adverse medication reactions were detected in 13 neonates. The median number of different medications ingested prenatally was 4.7. The four most commonly ingested prenatal medications were vitamins (97%), iron preparations (90%), headache/pain/arthritis medications (68%) and antinausea/vomiting medications (40%). The most commonly used medications during labor and delivery were oxytocin (73%), meperidine (33%) and promazine (25%). The use of strong narcotics during this period produced neonatal respiratory depression in some cases. The four most commonly prescribed postnatal medications were vitamin K1 (100%), gentamicin (10%), ampicillin (8%) and Poly-Vi-Sol (6%). The maternal interview indicated that most mothers were unaware of the influence that many medications can play upon the fetus. It is recommended that the pharmacist conduct a maternal medication interview prior to labor and delivery.  相似文献   
103.
An analysis is made of 24 cases of primitive lithiasis of the biliary tracts, viz; 10 of diffuse intrahepatic lithiasis, 9 of intrahepatic lithiasis localized in one of the ducts; and 5 of extrahepatic lithiasis. The most common cause were stenosis (14 cases) generally of idiopathic or congenital nature, followed by those of iatrogenic or tumoral origin. There were also cases of isolated or diffuse anomalus dilatation of the biliary ducts. A lithogenetic bile as well as infectious processes are rather considered secondary factors. The diagnosis of the real nature of the condiction was usually established in the postoperative period, this being an explanation why repeated surgery was so common (75%). There was a high postoperative mortality in the diffuse forms owing to severe manifestations of biliary sepsis perpetuated by the stones. Depending upon the individual cases the following procedures are proposed: 1) Biliodigestive anastomosis 2) Sphinteropapilloplasty 3) Dilatation and calibration of the stenosis 4) Postoperative instrumental extraction of calculi. The last-named procedure was carried out in 58% of the cases and result in an improvement in the serious prognosis. Primitive lithiasis should always be borne in mind when undertaking surgery of the biliary tracts in order to avoid additional surgery.  相似文献   
104.
The purpose of this investigation was to compare the peak physiological responses among four protocols that employed different amounts of handweighted exercise in 16 males (aged 26.3 +/- 4.1 years). The four protocols were (a) uphill treadmill running (UR; 3.36 m.s-1, 2.5% grade increase-3 min-1); (b) uphill treadmill walking while pumping 1.36-kg handweights (HW) (UWHW; 1.79 m.s-1, 5.0% grade increase x 3 min-1; (c) treadmill walking while pumping .91-kg HW (WHW; 1.79 m.s-1, 0% grade, .91-kg HW increase x 3 min-1); and (d) standing in place and pumping HW (SHW; arm work as described in WHW). It was hypothesized that the peak responses would be inversely proportional to the estimated muscle mass activated (i.e., UR = UWHW > WHW > SHW). Dependent variables included peak oxygen uptake (VO2 peak), peak heart rate (HRpeak), peak ventilation (Ve peak), and peak respiratory exchange ratio (RERpeak). No differences were noted between UR and UWHW with respect to any of the dependent variables. All variables (except RERpeak) were greater (p < .01) in UR and UWHW than either WHW or SHW. RERpeak was greater (p < .01) in UR and UWHW than in WHW. VO2 peak and HRpeak were greater (p < .01) in WHW when compared to SHW. Mean VO2 peak was 97.5, 69.7, and 60% of UR for UWHW, WHW, and SHW, respectively. Therefore, walking and pumping handweights provides a maximal stimulus to the oxygen transport system.  相似文献   
105.
Authorization is an important functionality that every hospital information system (HIS) should provide. An authorization mechanism permits information to be accessed only by properly authorized users. Authorization models and mechanisms have been widely investigated within the framework of HISs. However, their implementation into existing systems, that do not any longer meet increased authorization requirements, requires a major redesign effort. This paper describes a front end authorization mechanism that has been developed in an attempt to enhance the security features of an existing HIS without extensive modifications to the system structure.  相似文献   
106.
107.
Six cattle that had earlier exposure to Dermatobia hominis were infested experimentally with first-instar larvae of the parasite. Skin biopsies taken at intervals were studied in wax and in plastic sections. The avidin-biotin-peroxidase method was used to detect the presence and localization of host immunoglobulins (Igs) G and M and antigens of first and second instar larvae of Dermatobia hominis. The larvae penetrated actively through the skin and migrated towards the subcutaneous tissues. The great numbers of eosinophils suggest that they are the most important cell in mediating damage to D. hominis larvae. The immunoglobulins bound only to dead or moulting larvae in which access to binding sites may have been altered. This could represent a morphological manifestation of a mechanism that protects larvae from the host immune response. Large amounts of soluble antigens detected along the fistulous tract may be important in the maintenance of this tract by distributing the normal cicatrization process.  相似文献   
108.
Spasm of the saphenous vein frequently occurs during harvesting from the leg and high-pressure distension is required to restore an adequate diameter for grafting. Forceful distention has been shown to damage the intima and media and may predispose to subsequent occlusion of the vein graft. Various pharmacologic vasodilators are capable of relaxing veins; in this study, we carried out a systematic investigation to determine the appropriate agents and concentrations for use during vein graft operations. In organ baths, human saphenous vein segments were contracted with potassium or a thromboxane mimetic, and vasodilator agents were then applied. Glyceryl trinitrate, 7.2 micrograms/mL, or papaverine hydrochloride, 11.9 micrograms/mL, caused 80% to 100% relaxation of contraction induced by potassium or thromboxane. Verapamil, 15.5 micrograms/mL, relaxed the potassium contraction by 100% and the thromboxane contraction by 75%. Comparison of the time course of action showed that glyceryl trinitrate had a rapid onset and a short duration of maximal action, whereas verapamil (like papaverine) had delayed onset and a long duration. A mixture of glyceryl trinitrate and verapamil combined rapid onset with long duration of action. We now use a mixture of glyceryl trinitrate and verapamil (pH 7.4) topically and intraluminally during harvesting of the saphenous vein to provide a relaxed conduit for coronary artery bypass grafting.  相似文献   
109.
A new technique has been found that uses in-phase and quadrature phase (I/Q) demodulation to optimize the images produced with an amplitude-modulated laser imaging system. An I/Q demodulator was used to collect the I/Q components of the received modulation envelope. It was discovered that by adjusting the local oscillator phase and the modulation frequency, the backscatter and target signals can be analyzed separately via the I/Q components. This new approach enhances image contrast beyond what was achieved with a previous design that processed only the composite magnitude information.  相似文献   
110.
BACKGROUND: Human calcium oxalate (CaOx) nephrolithiasis may occur if urine is supersaturated with respect to the solid-phase CaOx. In these patients, dietary oxalate is often restricted to reduce its absorption and subsequent excretion in an effort to lower supersaturation and to decrease stone formation. However, dietary oxalate also binds intestinal calcium which lowers calcium absorption and excretion. The effect of increasing dietary oxalate on urinary CaOx supersaturation is difficult to predict. METHODS: To determine the effect of dietary oxalate intake on urinary supersaturation with respect to CaOx and brushite (CaHPO4), we fed 36th and 37th generation genetic hypercalciuric rats a normal Ca diet (1.2% Ca) alone or with sodium oxalate added at 0.5%, 1.0%, or 2.0% for a total of 18 weeks. We measured urinary ion excretion and calculated supersaturation with respect to the CaOx and CaHPO4 solid phases and determined the type of stones formed. RESULTS: Increasing dietary oxalate from 0% to 2.0% significantly increased urinary oxalate and decreased urinary calcium excretion, the latter presumably due to increased dietary oxalate-binding intestinal calcium. Increasing dietary oxalate from 0% to 2.0% decreased CaOx supersaturation due to the decrease in urinary calcium offsetting the increase in urinary oxalate and the decreased CaHPO4 supersaturation. Each rat in each group formed stones. Scanning electron microscopy revealed discrete stones and not nephrocalcinosis. X-ray and electron diffraction and x-ray microanalysis revealed that the stones were composed of calcium and phosphate; there were no CaOx stones. CONCLUSION: Thus, increasing dietary oxalate led to a decrease in CaOx and CaHPO4 supersaturation and did not alter the universal stone formation found in these rats, nor the type of stones formed. These results suggest the necessity for human studies aimed at determining the role, if any, of limiting oxalate intake to prevent recurrence of CaOx nephrolithiasis.  相似文献   
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