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51.
Progressive supranuclear palsy (PSP) and the parkinsonian variant of multiple-system atrophy (MSA-P) may present with a similar phenotype. Magnetic resonance diffusion-weighted imaging (DWI) has been shown to be a sensitive discriminator of MSA-P from Parkinson's disease (PD). We studied 20 PSP, 11 MSA-P, 12 PD patients and 7 healthy controls in order to investigate whether regional apparent diffusion coefficients (rADCs) help distinguish PSP and MSA-P; whether rADCs are correlated with clinical disease severity scores; and the relationship between brainstem and cerebellar volumes and rADCs in PSP and MSA-P. The Unified Parkinson's Disease Rating Scale, Hoehn and Yahr score, Mini Mental State Examination, and frontal assessment battery were recorded in all patients. Regional ADCs were measured in the middle cerebellar peduncle (MCP), caudal and rostral pons, midbrain, decussating fibers of the superior cerebellar peduncle, thalamus, putamen, globus pallidus, caudate nucleus, corpus callosum, frontal and parietal white matter, as well as the centrum semiovale. In MSA-P, rADCs in the MCP and rostral pons were significantly greater than in PSP (P < 0.001 and 0.009) and PD (P < 0.001 and = 0.002). Stepwise logistic regression revealed that the MCP rADC distinguishes MSA-P from PSP with a sensitivity of 91% and a specificity of 84%. Increased brainstem rADCs were associated with motor deficit in MSA-P and PSP. Increased rADCs in the pons and MCP were associated with smaller pontine and cerebellar volumes in MSA-P. rADCs distinguish MSA-P from PSP. These have a clinical correlate and are associated with reduced brainstem and cerebellar volumes.  相似文献   
52.
A number of different clinical syndromes have been associated with progressive supranuclear (PSP) tau pathology. Previous reports have suggested that atypical clinical phenotypes of PSP occur in familial disease, and might be associated with mutations of MAPT. We examined the association of PSP-susceptibility tau haplotypes in pathologically diagnosed PSP, separated according to initial clinical features into classic PSP and atypical PSP groups (PSP-Parkinsonism, PSP-P). These patients were screened for mutations in exons 1 and 10 of MAPT. No mutations were found in 75 patients (21 PSP-P), and H1c was associated with both Richardson's syndrome and PSP-P compared with controls. Routine screening for MAPT mutations in atypical PSP is not recommended.  相似文献   
53.
BackgroundIn recent years, uniportal video-assisted thoracic surgery (U-VATS) has been used for primary spontaneous pneumothorax (PSP). This study compared the perioperative outcomes of U-VATS and three-port VATS (3P-VATS) and sought to determine the risk factors for postoperative recurrence.MethodsFrom October 2010 to February 2017, 232 patients with PSP undergoing surgical treatment were enrolled in this study. The patients were divided into two groups: U-VATS (n=161) and 3P-VATS (n=71) depending on the period of surgery. Retrospective analysis of the perioperative results and the risk factors for recurrence was performed.ResultsBoth the operation time and duration of postoperative drainage were initially longer in the U-VATS group, but the difference gradually decreased such that ultimately there was no significant difference compared to the 3P-VATS group (P=0.10 and P=0.12, respectively). The duration of postoperative hospital stay and postoperative recurrence rate were not different between the two groups (P=0.084 and P=0.44, respectively). By multivariate analysis, the age (HR, 0.42, 95% CI: 0.24−0.72, P<0.01) and number of bullae (single vs. multiple: HR, 0.03, 95% CI: 0.002−0.54, P=0.02) were risk factors for recurrence.ConclusionsThe perioperative results and recurrence rate did not differ between the U-VATS and 3P-VATS groups, thereby demonstrating the non-inferiority of U-VATS. Postoperative risk factors for PSP recurrence were patient age and the number of bullae. Additional treatment may be needed to reduce recurrence in young patients with multiple bullae. Clinical registration number: The Institutional Review Board of Maebashi Red Cross Hospital (no. 2019-21).  相似文献   
54.
目的 探讨维思通与奥氮平用于首发性精神分裂症住院治疗患者的个人和社会功能的恢复.方法 在为期12周的双盲研究中,首发性精神分裂症患者被随机分为维思通组、奥氮平组.靶剂量为药物的最大推荐剂量:维思通为6 mg/d、奥氮平为30 mg/d.主要疗效指标是在12周单药治疗结束时比较维思通组和奥氮平组的个人和社会功能量表(PSP)均分、阳性和阴性症状量表(PANSS)总分变化差异.结果 在12周单药治疗结束时,维思通组的PANSS评分与奥氮平组无显著差异(P>0.05),但维思通组的PSP均分改善优于奥氮平组(P<0.01).结论 对于首发性精神分裂症患者,与奥氮平相比,维思通能够更显著的改善患者个人和社会功能,早日回归社会.  相似文献   
55.
Toxic microalgae outbreaks have caused significant economic losses in the Mexican aquaculture industry. Blooms that involve PSP and NSP phycotoxins are two of the most dangerous, causing harmful effects to the environment, economy and public health. The exact metabolic mechanism of these toxins in shrimp still remains unknown. Because shrimp consume microalgae their edible tissues are clearly possible vectors for human toxic syndrome. This study examined and verified the toxicological effects for white leg shrimp (Litopenaeus vannamei) exposed to different cell densities of Gymnodinium catenatum and Karenia brevis. Acute assays demonstrated good survival rates of shrimp at low densities of dinoflagellates (103 cell/L), while mortality and abnormal behavior were observed with higher densities (>104 cell/L). Chronic assays showed significant differences in survival rates, percentage of feed and weight gain of organisms exposed to the dinoflagellates with respect to controls. Furthermore, PSP and NSP toxins were detected in all the edible tissues. Gastric glands and muscle retained toxins for a longer period of time compared to other tissues, even after a depuration period. Histology damages were observed in the heart, gastric gland and brain. This study strongly supports that shrimp represent a potential risk for humans as unconventional vectors of phycotoxins.  相似文献   
56.
目的探讨长效利培酮微球对精神分裂症的远期临床疗效和安全性,以及对血清催乳素的影响。方法于2007年至2009年间入选56例精神分裂症患者,随机分入长效利培酮微球(RLAI)研究组和利培酮口服液(ROS)对照组进行为期1年的治疗,分别以痊愈率、缓解率、停药率、复发率和再住院率进行评价,评定两组的临床总体印象-严重度(CGI-S)与个人和社会功能评分(PSP)量表,并测定血清催乳素水平,以χ2检验和t检验进行统计分析。结果至研究终点时,RLAI组的临床治愈率和缓解率均高于ROS组,无停药、复发或再次住院发生,临床总体印象与个人和社会功能评分改善均优于ROS组。RLAI组血清催乳素水平及总体不良反应发生率均明显低于ROS组(P〈0.05)。与ROS组相比,RLAI组无1例发生不依从(P〈0.05)。结论长效利培酮微球的远期疗效、安全性及治疗依从性均优于利培酮口服液,适用于维持治疗。  相似文献   
57.
Decreased blood-brain barrier (BBB) efflux function of the P-glycoprotein (P-gp) transport system could facilitate the accumulation of toxic compounds in the brain, increasing the risk of neurodegenerative pathology such as Parkinson's disease (PD). This study investigated in vivo BBB P-gp function in patients with parkinsonian neurodegenerative syndromes, using [11C]-verapamil PET in PD, PSP and MSA patients. Regional differences in distribution volume were studied using SPM with higher uptake interpreted as reduced P-gp function. Advanced PD patients and PSP patients had increased [11C]-verapamil uptake in frontal white matter regions compared to controls; while de novo PD patients showed lower uptake in midbrain and frontal regions. PSP and MSA patients had increased uptake in the basal ganglia. Decreased BBB P-gp function seems a late event in neurodegenerative disorders, and could enhance continuous neurodegeneration. Lower [11C]-verapamil uptake in midbrain and frontal regions of de novo PD patients could indicate a regional up-regulation of P-gp function.  相似文献   
58.

Objective

Video-assisted thoracic surgery (VATS) for treatment of spontaneous pneumothorax refractory to nonoperative management was first reported in children by Rodgers in 1986 (Ann Surg. 1986; 204:677-680). Small series have shown success with apical blebectomy, mechanical or chemical (talc) pleurodesis, or combination techniques. We report the largest pediatric series of VATS for primary spontaneous pneumothorax (PSP) to date, to assess outcomes and compare techniques.

Methods

Retrospective review of all children undergoing VATS for PSP between 1999 and 2007 at 2 university-affiliated hospitals by the same group of surgeons. Mann-Whitney U tests and χ2 used (P < .05 = significant).

Results

Thirty-two patients underwent 41 VATS procedures (32 initial-30 unilateral, 2 bilateral; 9 subsequent-7 contralateral, 2 ipsilateral recurrences). Mean age at presentation was 16.5 years (range, 13-20 years). Blebs were identified at the time of VATS in 95% of patients, but in 12.5%, they were on lower lobes. Mean duration of postoperative air leak was 2.7 days, postoperative hospital length of stay was 5.0 days, and postoperative chest tube duration was 5.1 days; 2 patients required Heimlich valves, which were managed at home. Five different surgical techniques were used as follows: blebectomy plus mechanical pleurodesis had the shortest length of stay (4.3 days) and need for chest tube drainage (4.1 days) but had a higher recurrence risk (6% major, 16% minor) than blebectomy plus chemical pleurodesis. The risk of requiring an additional VATS procedure (ipsilateral or contralateral) was 28%. Mean follow-up was 46 months.

Conclusions

Blebectomy plus either mechanical or chemical pleurodesis were both associated with acceptable outcomes. Blebectomy plus chemical pleurodesis appears to have less risk of ipsilateral recurrence but longer postoperative stay and chest tube drainage.  相似文献   
59.
The clinical syndrome of pure akinesia has most often been associated with progressive supranuclear palsy (PSP) and is characterized by difficulty initiating gait and "freezing" during walking, writing and speaking. Similar syndromes have been described under the rubrics of primary progressive freezing gait and primary gait ignition failure. We investigated the specificity of the clinical syndrome of pure akinesia with gait freezing (PAGF) for PSP-tau pathology. Among 749 patients archived at the QSBB, only 7 fulfilled proposed diagnostic criteria of: gradual onset of freezing of gait or speech; absent limb rigidity and tremor; no sustained response to levodopa; and no dementia or ophthalmoplegia in the first 5 years of disease. In these cases detailed pathological examination was performed. PSP was the pathological diagnosis in six patients, and Parkinson's disease (PD) in the seventh. As defined, this syndrome had a positive predictive value of 86% for PSP-tau pathology. In the cases with PSP there were no additional features of coexistent vascular or PD and the median PSP-tau score was 3, reflecting relative mild tau load. The clinical syndrome of PAGF appears to have a high specificity for PSP-tau pathology. This relatively uncommon presentation of PSP-tau pathology has less severe tau accumulation than in the more common, "classic" PSP clinical phenotype: Richardson's disease.  相似文献   
60.
John P. Berry  Owen Lind 《Toxicon》2010,55(5):930-938
Exposure to cyanobacterial toxins in freshwater systems, including both direct (e.g., drinking water) and indirect (e.g., bioaccumulation in food webs) routes, is emerging as a potentially significant threat to human health. We investigated cyanobacterial toxins, specifically cylindrospermopsin (CYN), the microcystins (MCYST) and the “paralytic shellfish toxins” (PST), in Lago Catemaco (Veracruz, Mexico). Lago Catemaco is a tropical lake dominated by Cylindrospermopsis, specifically identified as Cylindrospermopsis catemaco and Cylindrospermopsis philippinensis, and characterized by an abundant, endemic species of snail (Pomacea patula catemacensis), known as “tegogolos,” that is both consumed locally and commercially important. Samples of water, including dissolved and particulate fractions, as well as extracts of tegogolos, were screened using highly specific and sensitive ELISA. ELISA identified CYN and PST at low concentrations in only one sample of seston; however, both toxins were detected at appreciable quantities in tegogolos. Calculated bioaccumulation factors (BAF) support bioaccumulation of both toxins in tegogolos. The presence of CYN in the phytoplankton was further confirmed by HPLC-UV and LC-MS, following concentration and extraction of algal cells, but the toxin could not be confirmed by these methods in tegogolos. These data represent the first published evidence for CYN and the PST in Lago Catemaco and, indeed, for any freshwater system in Mexico. Identification of the apparent bioaccumulation of these toxins in tegogolos may suggest the need to further our understanding of the transfer of cyanobacterial toxins in freshwater food webs as it relates to human health.  相似文献   
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