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41.
Neurosurgical Review - A preferred treatment for residual/recurrent pituitary adenomas has not been established. The existence of higher complication rates for revision surgeries remains under...  相似文献   
42.
Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
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Novel collagen scaffolds possessing predefined and reproducible internal channels with widths of 135 microm and greater have been produced. The process employed to make the collagen scaffold utilises a sacrificial mould, manufactured using solid freeform fabrication technology, and critical point drying technique. A computer aided design (CAD) file of the mould to be produced is created. This mould is manufactured using a phase change ink-jet printer. A dispersion of collagen is then cast into the mould and frozen. The mould is dissolved away with ethanol and the collagen scaffold is then critical point dried with liquid carbon dioxide. The effect of processing on the tertiary structure of collagen is assessed by monitoring the wavenumber of the N-H stretching vibration peak using Fourier transform infra-red spectroscopy and it is found that processing does not denature the collagen. Ultraviolet-visual spectroscopy was used to detect the presence of any contamination from the sacrificial mould on the collagen. The ability to use computer aided design and manufacture (CAD/CAM) provides a route to optimise scaffold designs using collagen in tissue engineering applications.  相似文献   
45.
The spin-echo procedure is the basic technique in a magnetic resonance (MR) study (the magnetization vector is flipped by 90° onto the ortogonal plane to the main magnetic field). Very soon after the MR procedure was developed, it was pointed out how important it is to achieve the needed contrast with shorter repetition times (TRs) to reduce the imaging time. Recently, fast imaging techniques have been introduced (partial flip angles, short TRs, and the lack of 180° radiofrequency pulses to refocus the spins are their main characteristics; the spins are refocused by the application of a gradient reversal technique). These techniques are particularly needed in pediatric neuroradiology, where the examination time must be as short as possible. At present, partial flip-angle techniques are almost completely replacing the conventional spin-echo procedure, but the variations in flip angle could result in a change in contrast. For these reasons, conventional spin-echo techniques may still be useful in a routine MR study.Presented at the 11th Meeting of the European Society for Paediatric Neurosurgery, Naples 1988  相似文献   
46.
Survival statistics of 4135 incident cases of digestive system cancers in the Umbria region of Italy are reported. The original data are derived from an ad hoc survey carried out in the period 1978--1982. Observed and relative rates at 1, 5 and 10 years are presented separately by sex and age (< 60 and 60 years). In both sexes there are very short survival rates for liver, bile duct and pancreas cancers, whereas about 50% of colon and rectum cancer patients survived at five years. About 20% stomach cancer patients survived at the same time. In males the survival rate for oesophagus cancer is close to 10%. The rates at ten years confirm the trend. Comparisons between sexes show that there is no significant differences in age at first diagnosis. Survival values are higher in females only for rectum cancers. In both sexes, for stomach, colon and rectum sites younger patients had a significantly longer survival than older ones.  相似文献   
47.
BACKGROUND: Wegener's granulomatosis is a systemic inflammatory disease of unknown etiology. Many studies suggest that autoimmune reactions are involved, and there is good evidence for the participation of immunocompetent cells. In that context, we examined the activation of polymorphonuclear neutrophils (PMNs) of patients with Wegener's granulomatosis. METHODS: In a prospective study, the expression on the surface of PMNs of CD64 and of the major histocompatibility class II (MHC II) antigen was measured by cytofluorometry in whole blood. The expression of those antigens was correlated to disease activity. RESULTS: Up to 15% of the peripheral PMNs of patients with active disease expressed MHC II. Follow-up studies showed that expression correlated closely with disease activity and that it decreased rapidly under immunosuppressive therapy. Expression of CD64 was seen in approximately 50% of the patients, regardless of disease activity. CONCLUSION: MHC II expression on PMNs might serve as a novel diagnostic marker for active disease and appears to be suitable for monitoring immunotherapy. Moreover, our data provide evidence that PMNs, which are normally MHC II negative, acquire MHC II antigens in the course of disease and may be an unrecognized function within the afferent limb of the immune response.  相似文献   
48.
Symptoms of psoas muscular abscess in children are nonspecific and differential diagnosis is made among diseases included in childreńs acute hip pain syndrome, imaging tests being necessary for diagnostic confirmation. During the first semester of 1995, 48,550 children were examined in Pronto Socorro do Instituto da Crian?a do Hospital das Clínicas da Faculdade de Medicina da Universidade de S?o Paulo, four of them diagnosed as having psoas muscular abscess (2 females and 2 males, ages varying from 1 to 12 years). All of them had nonspecific clinical features and diagnosis was confirmed by abdominal ultrasound and/or computerized tomography. Staphylococcus aureus was isolated as the etiologic agent in 3 children, findings similar to the ones in literature.  相似文献   
49.
H Baker  T H Joh  D J Reis 《Brain research》1982,256(2):157-165
The greater activity of tyrosine hydroxylase (TH) in substantia nigra and corpus striata of adult BALB/cJ than CBA/J mice, is attributable to differences in the number of dopamine neurons in the ventral midbrain tegmentum. To determine if strain differences in TH activity develop postnatally we have measured the development of TH in the midbrain (SN) and in the corpus striatum (CS). In the midbrain neonatal TH activity was 20% of adult levels. Thereafter, TH activity increased rapidly achieving adult levels by 11 days. A 25% "overshoot' above adult values at 15 days was followed by a gradual decrease to adult activity at 4 weeks. In the CS neonatal activity was about 10% of adult levels and increased slowly to reach adult values at 4 weeks. Striatal choline acetyltransferase (CAT) activity in the neonate was only 3.7% of adult values and at 21 days had only reached 70% of adult activity. Neonatal glutamic acid decarboxylase (GAD) activity was relatively high in both brain regions and increased gradually to adult activity by 4 weeks. Strain differences in TH activity were not present at birth but first appeared at 9 days in SN and 11 days in CS. Once established, the differences were maintained. These results suggest that strain differences in TH are most probably a consequence of differences in postnatal neuron survival, although the possibility that some neurons lose their phenotypic expression of TH cannot be excluded.  相似文献   
50.
The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections.  相似文献   
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