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91.
Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.  相似文献   

92.
Summary In the isolated nerve-muscle preparation of the cat nictitating membrane exposure to 0.04 M of the scorpion venom tityustoxin (TsTX) increased significantly the overflow of 3H-noradrenaline and the responses elicited by postganglionic nerve stimulation (1200 pulses, 0.5 ms duration, supramaximal voltage). Concentration effect curves to exogenous (-)-noradrenaline were not affected in the presence of this concentration of TsTX.The enhanced release of 3H-noradrenaline obtained during nerve stimulation as well as the increase of the postsynaptic responses observed during exposure to TsTX were more pronounced at 4 Hz than at 20 Hz. The increase in the overflow of noradrenaline observed with the toxin was selective for nerve stimulation since the release evoked by tyramine was not affected by TsTX.TsTX did not increase further the enhancement of 3H-noradrenaline release obtained in the presence of 18 mM tetraethylammonium (TEA). On the other hand, both TsTX and TEA were able to increase further the overflow of 3H-noradrenaline after block of the presynaptic alpha-adrenoceptors with phenoxybenzamine 0.29 or 2.9 M.In slices of rat cerebral cortex, TsTX 0.04 M increased 3H-noradrenaline release induced by 10 mM and by 20 mM KCl. The increased release evoked by the toxin was more pronounced for the lower concentration of K+.An increased release of 3H-noradrenaline in the presence of the toxin was also observed in rat hypothalamic slices stimulated with 20 mM K+. The K+ stimulated induced release of 3H-noradrenaline was also increased by 1.8 mM TEA. As shown for the peripheral nervous, system the simultaneous addition of TEA and TsTX did not result in additive effects when compared with the effects of the two agents added separately. Tityustoxin did not modify the metabolic pattern of the neurotransmitter released by K+ from rat hypothalamic slices.It is concluded that TsTX increases the stimulation-induced release of 3H-noradrenaline from both peripheral and central noradrenergic nerve terminals. Tityustoxin appears to act on the nerve terminal by a mechanism similar to that of TEA, an agent known to enhance the amount of noradrenaline released by nerve stimulation by increasing the duration of the action potentials.  相似文献   
93.
Summary The immunogenicity of a virus-induced rat osteosarcoma was studied utilizing the lymphocyte microcytoxicity test. Lymphocytes from progressor animals (in which the tumour progressed and metastasized) demonstrated an ability to kill osteosarcoma cells in vitro, while serum from these animals abrogated or blocked the cell-mediated cytotoxicity.Lymphocytes from regressor animals (in which tumours failed to develop or regressed spontaneously) also showed cytolytic activity against osteosarcoma cells in vitro, but their serum failed to block the lymphocyte-mediated cytolysis. Both progressor and regressor animals demonstrated the presence of humoral cytotoxic antibodies to tumour antigens on the basis of the ability of their serum to kill tumour cells in vitro. In an attempt to alter the fatal course of the disease in progressor animals, immunoprophylaxis and immunotherapy of the osteosarcoma in F1 hybrid rats war carried out by injecting them with parentalor, third party, allogeneic lymphoid cells. Injection of parental spleen lymphocytes into F1 hybrids produced a transient graft versus host reaction (GVHR), and prolonged the survival of the animals when lymphocytes were injected three days before, seven days after and on the day of tumour induction. Injection of allogeneic, third party lymphoid cells produced no detectable GVHR and prolonged the survival of F1 hybrids with osteosarcoma only when injected on the day of tumour induction. The prolonged survival of the groups treated with parental lymphoid cells was a result of stimulation of the host's immunological mechanisms during a transient GVHR, whereas the prolongation of survival in the group given allogeneic cells was most likely the result of a direct action of the donor lymphocytes on tumour cells, and not connected to a GVHR.SICOT Fellowship Award Paper, presented at the XIV-th World Congress of SICOT, Kyoto, Japan, October 15–20, 1978  相似文献   
94.
Summary A comparison of the effects of noradrenaline and 6-fluoronoradrenaline has been made at several peripheral sympathetic neuroeffector junctions. In the rat vas deferens preparation in the presence of 1 M cocaine, 6-fluoronor-adrenaline was found to be about 9 times more potent than noradrenaline as an agonist at presynaptic inhibitory 2-adrenoceptors. In the rabbit aorta, 6-fluoronoradrenaline had approximately one tenth of the potency of noradrenaline in stimulating the postsynaptic 1-adrenoceptors. Furthermore 6-fluoronoradrenaline, in contrast to previous reports, appears to be a substrate for the neuronal uptake process since exposure to cocaine potentiated the inhibition of the twitch response of the vas deferens by 6-fluoronoradrenaline. In addition, 6-fluoronoradrenaline increased the spontaneous outflow of radioactivity from rabbit pulmonary artery strips prelabelled with 3H-noradrenaline and this increase was blocked by cocaine (30M).These results demonstrate that 6-fluoronoradrenaline is a preferential 2-adrenoceptor agonist which is a substrate for the neuronal uptake process in peripheral sympathetically innervated smooth muscle preparations.  相似文献   
95.
Sarcolemmal membranes prepared by "gas dissection" from monolayers of cultured neonatal rat heart cells were studied with respect to their ability to bind calcium. Lanthanum displacement of calcium was 168 +/- 7 nmol/mg sarcolammel protein. This represents 3.21 mmol Ca/kg dry weight original cells on the basis of the measured membrane protein: dry cell weight ratio of 19.1 g/kg. Lanthanum-displaceable calcium from whole cells was essentially equal (3.32 mmol/kg dry weight), which indicates that all calcium displaceable from whole cells by lanthanum is localized to sarcolemmal sites. The potency of a series of divalent cations for calcium displacement from the sarcolemma was according to similarity of their crystal radii to that of calcium (cadmium greater than manganese greater than magnesium). This order was the same for the cations' ability to displace calcium from whole cells and for their ability to uncouple excitation from contraction in neonatal papillary muscle. The membranes were treated with four enzymes: phospholipase A2, phospholipase C, phopholipase D, and neuraminidase. Phospholipase A2 and phospholipase D produced significantly increased calcium-binding. The increased binding secondary to phospholipase A2 treatment was eliminated by an albumin wash which was indicative of binding to the fatty acid product of hydrolysis. The increase after phospholipase D treatment can be attributed to an increase in phosphatidate, with attendant increase in net anionic charge on the membrane.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
96.
Risk factors for pneumonia were analysed in a large population of critically ill patients, collected in two prospective multicentre pneumonia studies in Italy. Twenty-three intensive care units were involved and the study time was 150 unit months. Only patients without previous pulmonary infection, with intensive care unit stay 48 hours and no rapidly irreversible illness at admission were included. The incidence of pneumonia in the 1475 selected patients was 15% (220 cases). 239 patients died in ICU; the mortality rate was significantly higher in patients developing pneumonia (p<0.0001); pneumonia was found to be an independent highly significant risk factor for death in critically ill patients (OR = 3.88; p<0.0001).Multivariate analysis of seven risk factors for pneumonia showed a significantly higher risk in patients with neuromuscular disease (OR = 3.8, p<0.002), impairment of airway reflexes at admission (OR = 2.93, p<0.0001), and 24h respiratory assistance (OR=3.05, p<0.0001). Impairment of airway reflexes at admission to the emergency room or intensive care unit identifies the population who will experience 3/4 of the overall lower respiratory tract infections.Rapid recognition of at-risk patients seems clinically important and may improve awareness programs and preventive approaches.Intensive Care Unit Group for Infection Control (I.C.U.G.I.C.), a list of participating physician co-authors of the paper is reported at the endCorresponding author.  相似文献   
97.
Orbital drainage from cerebral arteriovenous malformations   总被引:3,自引:0,他引:3  
OBJECTIVE: To describe the neuro-ophthalmic findings in patients with orbital drainage from cerebral arteriovenous malformations (AVMs). METHODS: We reviewed the records of 100 consecutive adult patients with cerebral AVMs who presented to our institution during a 4-year period. All patients with orbital drainage were identified, and their neuro-ophthalmic evaluations were reviewed. RESULTS: Three patients (3%) were identified with orbital drainage from a cerebral AVM. The first patient presented with typical chiasmal syndrome (reduced visual acuity, bitemporal hemianopia, and optic atrophy). Magnetic resonance imaging demonstrated a large left temporal and parietal lobe AVM with compression of the chiasm between a large pituitary gland and a markedly enlarged carotid artery. The second patient presented with headaches and postural monocular transient visual obscurations. Examination revealed normal visual function with minimal orbital congestion and asymmetrical disc edema, which was worse in the left eye. Magnetic resonance imaging revealed a large right parietal and occipital lobe AVM without mass effect or hemorrhage and an enlarged left superior ophthalmic vein. The third patient had no visual symptoms and a normal neuro-ophthalmic examination; a right parietal lobe AVM was discovered during an examination for the cause of headaches. CONCLUSION: Orbital drainage from cerebral AVMs is rare. Manifestations may include anterior visual pathway compression, dilated conjunctival veins, orbital congestion, and asymmetrical disc swelling.  相似文献   
98.
Zusammenfassung Ziel: Untersucht wurde die Treffsicherheit der MRT bei der Lokalisationsdiagnostik nichtpalpabler Hoden. Material und Methode: 17 Jungen im Alter von 11 Monaten bis 9 Jahren wurden zur Lokalisationsdiagnostik eines oder beider nichtpalpabler Hoden (insgesamt 20 Hoden) mittels MRT (1T-Ger?t, Magnetom Expert, Siemens) im Zeitraum von 1992–1995 untersucht. Die Lokalisationen wurden in: Bauchhoden und hohe und tief gelegene Leistenhoden eingeteilt. Die Patienten wurden anschlie?end laparoskopisch oder offen operiert und der evtl. vorhandene hochstehende Hoden im Skrotum fixiert. Ergebnisse: 16 Hoden (80%) wurden durch die MRT-Diagnostik pr?operativ richtig lokalisiert bzw. eine Anorchie richtig diagnostiziert. Zwei Hoden (10%) wurden falsch lokalisiert, 2 Hoden (10%) wurden in der MRT beschrieben, obwohl eine Anorchie vorlag. Von unseren 5 Anorchief?llen konnten mittels MRT nur 3 diagnostiziert werden. Schlu?folgerung: Die MRT erreicht eine gute Trefferquote (80% positive Vorhersagewahrscheinlichkeit) in der pr?operativen Lokalisationsdiagnostik des nichtpalpablen Hodens. Da die MRT eine Anorchie nicht mit ausreichender Sicherheit von einem Kryptorchismus differenzieren kann, kann ein fehlender Hodennachweis in der MRT die endoskopische Diagnostik nicht substituieren. Bei geplanter endoskopischer Diagnostik kann im Regelfall auf die pr?operative MRT-Diagnostik verzichtet werden.   相似文献   
99.
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
100.
Hypospadias trends in two US surveillance systems   总被引:6,自引:0,他引:6  
OBJECTIVE: Hypospadias is a common congenital anomaly, the cause of which is unknown. Unexplained increases in the rates of hypospadias occurred in five European countries in the 1970s and 1980s. We examined data from two birth defects surveillance systems in the United States for evidence of similar trends. METHODOLOGY: The Metropolitan Atlanta Congenital Defects Program (MACDP) provided birth prevalence rates from 1968 to 1993. The nationwide Birth Defects Monitoring Program (BDMP) provided rates from 1970 to 1993. MACDP data are population-based and could be categorized by the severity of the hypospadias. BDMP data allowed analysis of rate trends for the four census regions of the United States. RESULTS: Data from both surveillance systems showed an approximate doubling of hypospadias rates in the 1970s and 1980s. MACDP data showed that the rate of severe cases increased while the ratio of mild to severe cases decreased. BDMP data showed that hypospadias rates increased markedly in all four regions of the United States. CONCLUSIONS: The observed increases are unlikely to be attributable to increased sensitivity of the surveillance systems or the identification of more mild cases by physicians over time, because either trend would have increased rather than decreased the ratio of mild to severe cases. If real, these trends represent the largest number of cases and the first report of an increase in hypospadias rates outside of Europe. Additional investigation of a possible increase in hypospadias rates is warranted.  相似文献   
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