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排序方式: 共有996条查询结果,搜索用时 15 毫秒
1.
2.
A double or bilobar gallbladder as a cause of severe complications after (laparoscopic) cholecystectomy 总被引:1,自引:1,他引:0
A double or bilobar gallbladder is a rare congenital anomaly. If not recognized during preoperative evaluation or operation, it can cause severe complications. We describe two cases in which a second operation had to be performed because of the presence of a second or bilobar gallbladder that was not recognized in the preoperative evaluation and during (laparoscopic) cholecystectomy. The types of anomalies, the concomitant pathology, and treatment are discussed. 相似文献
3.
We studied the reported frequencies of clinical complaints of neuromuscular hyperexcitability (muscle cramps and fasciculations) in random samples of 527 Dutch adults, who were and 253 Dutch adults, who were not suffering from musculoskeletal pain and tenderness. Data were collected by telephone-interview and by self-administered questionnaire. Muscle cramps and fasciculations were recorded more frequently in the category that suffered from musculoskeletal pain (p less than 0.001). This association warrants further investigation into the possible intrinsic role of neuromuscular hyperexcitability in musculoskeletal pain and primary fibromyalgia. 相似文献
4.
5.
Rensink AA Otte-Höller I de Boer R Bosch RR ten Donkelaar HJ de Waal RM Verbeek MM Kremer B 《Neurobiology of aging》2004,25(1):93-103
Amyloid-beta (Abeta) deposition in the cerebral arterial and capillary walls is one of the characteristics of Alzheimer's disease and hereditary cerebral hemorrhage with amyloidosis-Dutch type. In vitro, Abeta1-40, carrying the "Dutch" mutation (DAbeta1-40), induced reproducible degeneration of cultured human brain pericytes (HBP), by forming fibrils at the cell surface. Thus, this culture system provides an useful model to study the vascular pathology seen in Alzheimer's disease. In this study, we used this model to investigate the effects of insulin on Abeta-induced degeneration of HBP, as it has been mentioned previously that insulin is able to protect neurons against Abeta-induced cell-death. The toxic effect of DAbeta1-40 on HBP was inhibited by insulin in a dose-dependent matter. Insulin interacted with Abeta and inhibited fibril formation of Abeta in a cell-free assay, as well as at the cell surface of HBP. Our data indicate that the formation of a fibril network is essential for Abeta-induced cell death in HBP. Additionally, insulin may be involved in the regulation of Abeta fibrillization in AD. 相似文献
6.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
7.
Initial validation of the SLEEP-50 questionnaire 总被引:1,自引:0,他引:1
Initial psychometric properties of the SLEEP-50 questionnaire, designed to detect sleep disorders as listed in the Diagnostic and Statistical Manual of Mental Disorders (4th ed., Text Revision), were examined. The sample consisted of 377 college students, 246 sleep patients, 32 nightmare sufferers, and 44 healthy volunteers. The internal consistency was high (Cronbach's alpha = .85); test-retest correlations fell between .65 and .89. Principal component analysis with a direct oblimin rotation revealed a factor structure that closely matched the designed structure. Sensitivity and specificity scores were promising for all sleep disorders; the agreement between all clinical diagnoses and SLEEP-50-classifications was substantial (kappa = .77). These initial findings indicate that the SLEEP-50 seems able to detect a variety of sleep disorders. The SLEEP-50 can aid in screening for common sleep disorders in the general population. 相似文献
8.
Evidence for the involvement of a Bemisia tabaci GroEL homologue in the transmission of tomato yellow leaf curl geminivirus (TYLCV) is presented. A approximately 63-kDa protein was identified in B. tabaci whole-body extracts using an antiserum raised against aphid Buchnera GroEL. The GroEL homologue was immunolocalized to a coccoid-shaped whitefly endosymbiont. The 30 N-terminal amino acids of the whitefly GroEL homologue showed 80% homology with that from different aphid species and GroEL from Escherichia coli. Purified GroEL from B. tabaci exhibited ultrastructural similarities to that of the endosymbiont from aphids and E. coli. In vitro ligand assays showed that tomato yellow leaf curl virus (TYLCV) particles displayed a specific affinity for the B. tabaci 63-kDa GroEL homologue. Feeding whiteflies anti-Buchnera GroEL antiserum before the acquisition of virions reduced TYLCV transmission to tomato test plants by >80%. In the haemolymph of these whiteflies, TYLCV DNA was reduced to amounts below the threshold of detection by Southern blot hybridization. Active antibodies were recovered from the insect haemolymph suggesting that by complexing the GoEL homologue, the antibody disturbed interaction with TYLCV, leading to degradation of the virus. We propose that GroEL of B. tabaci protects the virus from destruction during its passage through the haemolymph. 相似文献
9.
The presence of an extensive intraductal component following a limited excision correlates with prominent residual disease in the remainder of the breast 总被引:14,自引:0,他引:14
R Holland J L Connolly R Gelman M Mravunac J H Hendriks A L Verbeek S J Schnitt B Silver J Boyages J R Harris 《Journal of clinical oncology》1990,8(1):113-118
Previous studies of patients with infiltrating ductal breast cancer treated with conservative surgery (ie, limited excision) and radiotherapy have indicated that the presence of an extensive intraductal component (EIC) in the excision specimen is highly associated with subsequent breast recurrence. The reason for this association is not clear, but possible explanations include the presence of more extensive disease in the breast or increased radiation resistance among tumors with an EIC (EIC+) compared with those without (EIC-) tumors. To investigate this association further, we related the presence or absence of an EIC in the primary tumors of 214 women who underwent mastectomy to the likelihood of finding additional foci of cancer in their mastectomy specimens using a correlated pathologic-radiologic mapping technique. Primary tumors that were EIC+ were significantly more likely to have carcinoma in the remainder of the breast than those which were EIC--(74% v 42%; P = .00001). This difference was primarily due to the presence of residual intraductal carcinoma. Seventy-one percent of EIC+ patients had residual intraductal carcinoma compared with 28% of EIC-patients (P less than .00001). In particular, 44% of EIC+ patients had "prominent" residual intraductal carcinoma compared with 3% of EIC-patients (P less than .00001). We conclude that patients whose tumors contain an EIC more frequently have a large subclinical tumor burden in the remainder of the breast compared with patients whose tumors do not contain an EIC. This observation may explain the association between EIC and subsequent breast recurrence when patients are treated with a limited excision before radiotherapy. 相似文献
10.
Relation between indicators for quality of occupational rehabilitation of employees with low back pain 总被引:7,自引:5,他引:2 下载免费PDF全文
W. E. van der Weide J. H. Verbeek F. J. van Dijk 《Occupational and environmental medicine》1999,56(7):488-493
OBJECTIVES: To assess if the implementation of guidelines for occupational rehabilitation of patients with low back pain by means of process variables--a set of objective criteria for technical performance and continuity of care--led to a better outcome in clinical and return to work variables. METHODS: The study group consisted of 59 patients with at least 10 days of sick leave because of low back pain. Univariate analyses as well as multiple logistic regression and Cox's regression analyses were performed to assess the relation between quality of care and outcome. RESULTS: Process indicators for technical competence, continuity of care, and total performance were all significantly related to satisfaction of employees. Continuity of care and total performance were significantly related to working status at 3 months, and time to return to work. None of the process indicators was related to pain or disability after 3 months follow up. Satisfaction was not related to any of the other outcome variables. This indicates that if guidelines for occupational rehabilitation are met, outcome is better. CONCLUSION: Quality of the process of care was related to outcome. Interventions of occupational physicians need improvement in the areas of continuity of care and communication with treating physicians. The effectiveness of an improved intervention should be studied in a subsequent randomised clinical trial.
相似文献