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151.
We used whole brain functional MRI to investigate the neural network specifically engaged in the recognition of "biological motion" defined by point-lights attached to the major joints and head of a human walker. To examine the specificity of brain regions responsive to biological motion, brain activations obtained during a "walker vs. non-walker" discrimination task were compared with those elicited by two other tasks: (i) non-rigid motion (NRM), involving the discrimination of overall motion direction in the same "point-lights" display, and (ii) face-gender discrimination, involving the discrimination of gender in briefly presented photographs of men and women. Brain activity specific to "biological motion" recognition arose in the lateral cerebellum and in a region in the lateral occipital cortex presumably corresponding to the area KO previously shown to be particularly sensitive to kinetic contours. Additional areas significantly activated during the biological motion recognition task involved both, dorsal and ventral extrastriate cortical regions. In the ventral regions both face-gender discrimination and biological motion recognition elicited activation in the lingual and fusiform gyri and in the Brodmann areas 22 and 38 in superior temporal sulcus (STS). Along the dorsal pathway, both biological motion recognition and non-rigid direction discrimination gave rise to strong responses in several known motion sensitive areas. These included Brodmann areas 19/37, the inferior (Brodmann Area 39), and superior parietal lobule (Brodmann Area 7). Thus, we conjecture that, whereas face (and form) stimuli activate primarily the ventral system and motion stimuli primarily the dorsal system, recognition of biological motion stimuli may activate both systems as well as their confluence in STS. This hypothesis is consistent with our findings in stroke patients, with unilateral brain lesions involving at least one of these areas, who, although correctly reporting the direction of the point-light walker, fail on the biological motion task.  相似文献   
152.

Background and objectives

Percutaneous catheter drainage (PCD) is used as a first step in the management of symptomatic fluid collections in patients with acute pancreatitis (AP). We aimed to compare the outcome of patients with acute necrotic collection (ANC) and those with walled-off necrosis (WON), who had undergone PCD as a part of management of AP.

Methods

Consecutive patients of AP with symptomatic ANC or WON undergoing PCD were evaluated. Primary outcome measures were need for additional surgical necrosectomy and mortality. Secondary outcome measures were need for up-gradation of first PCD, need for additional drain, in-hospital as well as total duration of PCD and length of hospital stay.

Results

Indications of PCD in 375 patients (258 with ANC and 117 with WON) were suspected infected pancreatic necrosis (n?=?214), persistent organ failure (n?=?117) and pressure symptoms (n?=?44). Need for additional surgical necrosectomy was seen in 14% patients with ANC and in 12% of patients with WON (p?=?0.364) and mortality was 19% in patients with ANC as compared to 13.7% in those with WON (p?=?0.132). There was no significant difference in the secondary outcome parameters between patients who underwent PCD for ANC or WON. Complications of PCD were comparable between patients with ANC and WON except development of external pancreatic fistula which occurred more often in patients with WON than in those with ANC (24.4% versus 34.2% respectively, p?=?0.034).

Conclusion

Persistent organ failure in more often an indication of PCD in patients with ANC than in WON and suspected infection is more commonly an indication in WON than in ANC. Early PCD is as efficacious and safe as delayed PCD.  相似文献   
153.
Monomeric mouse prolactin containing small amounts of 125I-labelled prolactin was administered to adult female mice of a high (C3H/St) and low (C57BL/St) mammary tumour strain. Their endogenous prolactin had been suppressed with 2-bromo-alpha-ergocryptine. The chromatographic profile, on Sephadex G-100, of prolactin in the serum of mice injected with mouse prolactin was compared by direct measurement (radioactivity count) and by radioimmunoassay (RIA) at several intervals after injection. With both methods, the injected hormone was found in the serum in predominantly two molecular sizes, the so-called 'big' and 'little' forms. Although 'little' prolactin in both strains constituted a constant 80% of the total hormone at most intervals by direct measurement, it comprised a comparatively smaller proportion by RIA. In addition, the RIA-determined 'little' prolactin, after reaching maximum levels at 15 min, progressively decreased with time, the decrease being greater in the C3H/St than in the C57BL/St strain. Similar experiments with mouse growth hormone revealed no such discrepancies between the radioactivity counts and the RIA measurements. A fraction of both 'big' and 'little' forms in the C3H/St strain failed to precipitate completely after the material had been incubated with an antiserum to mouse prolactin. These results demonstrate that the prolactin injected into mice is metabolized in serum into two non-immunoreactive forms, one that elutes with the same elution volume on Sephadex G-100 column as the monomer and the other that elutes as the 'big' form. Furthermore, the loss of immunoreactivity of monomeric mouse prolactin is greater in the high-tumour C3H/St strain than in the low-tumour C57BL/St strain. Endogenous immunoreactive prolactin, on the other hand, was found mainly in the 'big' form in the serum of female mice of the C3H/St strain under basal conditions, whereas it was present only in the 'little' form in comparable mice of the C57BL/St strain, even though pituitary extracts of both strains contained mainly the 'little' form. These results support the concept that monomeric prolactin in the systemic circulation of the tumour-prone C3H/St strain is largely in a non-immunoreactive form.  相似文献   
154.
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156.
Bilateral Morgagni hernia is a rare entity. A patient of bilateral Morgagni hernia presenting as mediastinal mass is being reported. The hernial contents included transverse colon so the diagnosis could be confirmed preoperatively by barium enema. Surgery was curative.  相似文献   
157.
We previously demonstrated that treatment with indomethacin in vivo significantly blunted the glucagon-induced glycemic response in the rat. This prostaglandin synthetase (cyclo-oxygenase) inhibitor also accentuated the evanescent effect of glucagon on hepatic glucose output in the intact, anesthetized rat. In this report, we present evidence that impairment of glucagon action in the rat liver by indomethacin is mediated through its inhibitory effect on both cAMP-dependent and cAMP-independent hepatic protein kinase. Indomethacin treatment did not have a measurable effect on any of the other components of the glucagon transducer system. Furthermore, infusion with glucagon for two hours that maintained plasma glucagon values at high physiological levels significantly reduced hepatic cAMP-dependent protein kinase activity without altering its Km. Glucagon infusion also down-regulated its own hepatic receptors and glucagon-stimulated cAMP production; prostaglandin E1-stimulated cAMP production was not affected. We concluded that prostaglandins may play a role in the regulation of hepatic protein kinases involved in the glucagon-stimulated glycogenolytic response and that glucagon-induced down-regulation extends at least to the hepatic protein kinases. However, a direct effect of indomethacin or protein kinase and the adenylate cyclase complex cannot be ruled out.  相似文献   
158.
In the present study, the effects of morphine and pethidine on coronary vessel resistance (CPP), blood pressure (BP), and experimental myocardial infarction-induced cardiac arrhythmia were investigated. Both morphine and pethidine induced a fall in CPP and BP and inhibited the cardiac arrhythmia. The morphine effects on CPP and BP were largely blocked by mepyramine. The effects of pethidine, on the other hand, were not blocked by mepyramine, propranolol, or atropine. An interesting dose dependent inhibition of cardiac arrhythmia was observed with pethidine.  相似文献   
159.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Our earlier studies have established improved cold tolerance in the transgenic tomato (Solanum lycopersicum...  相似文献   
160.
Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), particularly the macular form, is difficult when based on microscopy. This study compared the results of nested PCR (91.9% positive samples) with imprint smear microscopy (70.9% positive samples) for 62 PKDL samples. We found that nested PCR, which indicated 87.5% positivity for the macular lesions, compared to 41.6% positivity by imprint smear microscopy, is an efficient method for early diagnosis of PKDL.  相似文献   
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