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71.
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A group of patients suffering from anxiety, as assessed by general practitioners and psychologists using research criteria for generalised anxiety, were treated with either diazepam or placebo double blind for six weeks. This active treatment period was preceded by a one week single blind placebo "wash in" period and followed by a two week single blind placebo "wash out" period. The results suggest that diazepam can produce rebound anxiety and withdrawal symptoms when used in moderate doses and for what has previously been regarded as a safe length of time. If replicated these results have implications for the therapeutic use of benzodiazepines.  相似文献   
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Hamsters in deep experimentally induced hypothermia, at body temperatures between 7 degrees C and 11.5 degrees C, were microinjected with 5-HT and ACh at brain sites in the anterior-preoptic area of the hypothalamus (AH/POA). ACh or 5-HT was injected into an AH/POA site at different starting core temperatures in different groups of hypothermic hamsters. Colonic temperatures (Tc) were maintained, following He-Cold induction, in a temperature controlled environmental chamber and measured with a YSI thermister probe and YSI telethermometer. Injections of either 5-HT or ACh at Tc's between 7.0 degrees C and 9.0 degrees C elicited only modest increases in Tc i.e., 0.3 degrees C--0.6 degrees C, respectively. As Tc increased, however, to ranges between 9.1 degrees C--10.0 degrees C and in different animals to greater than 10 degrees C both ACh and 5-HT at the same sites elicited significant increases in Tc, 1.5 degrees C for 5-HT and 2.2 degrees C for ACh compared to saline injections. These data suggest that at the lowest Tc's we are observing a "cold block" of temperature sensitive sites in the AH/POA. Increasing the starting Tc beyond 9.0 degrees C however, evokes significant increases in heat-gain following AH/POA injection of either ACh or 5-HT. These data are consistent with Myers' observations concerning the organization of heat-gain mechanisms at AH/POA sites. In addition, they suggest that both the afferent limb of the heat-gain circuit (5-HT) and the efferent limb of the circuit (ACh) are functionally impaired when Tc is close to the physiological limit in the He-Cold hypothermic hamster.  相似文献   
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BackgroundPortal vein embolization before liver resection is considered the therapy of choice for patients with inadequate future liver remnants. The concept of radioembolization with Yttrium-90 to achieve the same goal has limited data.MethodsWe retrospectively compared patients who underwent portal vein embolization and Yttrium-90 lobectomy before resection of hepatocellular carcinoma in patients with chronic liver disease.ResultsSeventy-three patients underwent portal vein embolization and 22 patients underwent Yttrium-90. Forty-seven percent of patients before portal vein embolization required additional procedures for tumor control, and 27% of patients after Yttrium-90 required additional procedure to mainly induce further hypertrophy. Both therapies achieved the goal of future liver remnants >40%, but the degree of hypertrophy was significantly higher in Yttrium-90 patients (63% for Yttrium-90, 36% for portal vein embolization, P < .01). Tumor response was significantly better with Yttrium-90, achieving complete response in 50% of patients. Resectability rate was higher after portal vein embolization (85% for portal vein embolization, 64% for Yttrium-90, P = .03). Tumor progression was the most common reason precluding surgery. Complete tumor control was the reason not to pursue surgery in 18% of patients after Yttrium-90.ConclusionBoth preoperative portal vein embolization and Yttrium-90, increases liver resectability rates by inducing hypertrophy of future liver remnants in patients with hepatocellular carcinoma and chronic liver disease. Yttrium-90 lobectomy achieved better tumor control and provided more time to assess therapy response, optimizing the indication for surgery.  相似文献   
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Linear plasmids are widely distributed in isolates of Borrelia burgdorferi, but the prevalence of supercoiled circular (SC) plasmids has not been clearly established. Enriching for SC plasmids on ethidium bromide density-gradients revealed that a low passage of strain Sh-2-82 of B. burgdorferi has at least six SC plasmids (8.4, 8.8, 20, 26, 29 and 51 kb). In addition, several of the SC plasmids were observed by electron microscopy to form concatenated structures. Because of the high incidence of coupled SC plasmids and the effect of such structures on plasmid mobility, we suggest that they could be mistaken for a single DNA species having a high molecular weight when total DNA from B. burgdorferi is examined by agarose-gel electrophoresis. Of the six SC plasmids in strain Sh-2-82, four could still be detected after two years of continuous in vitro passaging in BSK II medium. The two SC plasmids lost after a maximum of 20 passages, pBBC1 (8.4 kb) and pBBC2 (8.8 kb), shared a high degree of DNA sequence similarity, suggesting that their apparent instability may be a unique feature of these closely related plasmids. Two higher passaged variants of strain Sh-2-82, P20 and P202, were shown by hybridization to lack pBBC1 and pBBC2 sequences and were unable to infect the white-footed mouse, Peromyscus leucopus. However, six of 14 unrelated isolates that infected this rodent and Syrian hamsters also lacked pBBC1 and pBBC2 sequences. None of five unrelated but highly passaged non-infectious isolates carried either pBBC1 or pBBC2 sequences. These data indicate that pBBC1 and pBBC2 do not encode constitutively expressed proteins required for infectivity in our experimental system. Nevertheless, eight of the 13 infectious strains examined did carry pBBC1 and/or pBBC2, indicating that these two closely related plasmids can be detected in a wide range of unrelated isolates of B. burgdorferi.  相似文献   
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Primary malignant non-Hodgkin's lymphomas account for 0.4% of malignant neoplasms arising in the bladder and female urethra, but do not comprise a uniform group, and three subgroups can be identified which account for a majority of cases. The most common is a low-grade B-cell lymphoma similar to neoplasms arising in the mucosa-associated lymphoid tissue at other sites — so-called MALTomas. These generally display indolent behavior. A second group accounting for approximately one-fifth of cases is composed almost entirely of large lymphoid cells, and these tumors have a poor prognosis. A third possible group comprises only a few patients who present with diffuse thickening of the bladder wall, and have a poor prognosis. The authors present a new case which suggests that this latter group may be of T-cell origin. In addition to these three subtypes, others no doubt await recognition. The different forms of primary lymphoma appear to require different treatments, and some guidelines are proposed.  相似文献   
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