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231.
Surgery is accepted as one of the most demanding professions that create both physical and mental strain on the performers. Therefore, the authors aimed to elucidate the mental burden of surgeons, which is dedicated to operative stress. They also tested the hypotheses that participating in surgery creates mental stress on surgeons that leads to cardiovascular changes, and that this stress is more pronounced for actual operators than for first assistants. The method chosen for this purpose was an analysis of heart rate variability. Twelve surgeons (five plastic surgery staff and seven plastic surgery residents) were monitored by a digital ambulatory Holter recorder on at least two occasions. Half of the recordings were carried out on operating days and the other half on office days. Heart rate variability indices (low frequency, high frequency, high frequency/low frequency ratio, and heart rate) were analyzed from those recordings using computerized research tool software. The heart rate variability indices of the operators showed statistically significant differences between operating days and office hours in favor of an increased sympathetic and decreased parasympathetic activity for the former. For first assistants, three of the parameters, with the exception of heart rate, changed in favor of a sympathetic predominance over parasympathetic activity; these changes were also statistically significant. These results showed a sympathetic hyperactivity for both operators and first assistants during the operations. When the sympathovagal balance of the actual operators was compared with that of assistants, the former group showed a more pronounced sympathetic arousal. This difference is accepted as a proof for the mental stress of the surgery being the main factor responsible for the sympathetic hyperactivity that we detected during the operations. Surgeons continuously face a unique mental strain that other professions rarely bring forth, and these psychological stressors are associated with alterations in cardiac autonomic control that may contribute to the development of cardiac disease. Prolonged sympathetic hyperactivity could anticipate cardiac discomfort in more experienced surgeons with marginal cardiac reserve. Such cardiac diseases would be reconsidered as occupation-related illnesses, which might be reimbursed to the physician. In addition, the legal responsibility of surgeons concerning their unfavorable results might be assessed with more understanding with a realization of their undue working conditions.  相似文献   
232.
In addition to two known acetoxy-eudesmanolides and two furanogermacranes from the fruits of Smyrnium olusatrum a new highly unstable acetoxy-furanoeudesmane was obtained, which obviously is the precursor of the two acetoxy-eudesmanolides.  相似文献   
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OBJECTIVE: To evaluate the differences among pathologists' interpretations in gastrointestinal stromal tumors (GISTs) and to demonstrate the usefulness of quantitative pathology in the assessment of immunohistochemical staining. STUDY DESIGN: Twenty GISTs were separately evaluated by 4 pathologists by the visual estimation method using a 6-antibody panel. Each case was then quantitatively measured with a computer-assisted image analysis system by 2 pathologists. Cohen's kappa test was performed for statistical analysis. RESULTS: All GISTs showed some degree of expression of CD 117, CD34, SMA and Ki-67. No case was immunoreactive for desmin or S-100 protein. There were remarkable differences in the pathologists' visual estimations. Moreover, the discrepancies between visual and quantitative methods were noteworthy. The differences in interpretations showed the greatest variability for Ki-67, which is known to be related to poor prognosis. CONCLUSION: Quantitative pathology in assessment of immunohistochemical staining of GISTs may improve the consistency in the interpretation of staining results and provide some degree of reproducibility.  相似文献   
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Aspiration pneumonitis refers to acute chemical lung injury caused by aspiration of sterile gastric contents. The aim of this study was to evaluate the role of quercetin (QC) in acid aspiration-induced lung injury in rats. Twenty-eight female Sprague–Dawley rats were used and divided into the following groups (n = 7): sham (aspirated normal saline, S), hydrochloric acid (aspirated HCl), S plus treatment with QC (S + QC), and HCl plus treatment with QC (HCl + QC). After aspiration, the treatment groups received QC 60 mg/kg/day intraperitoneally once a day for 7 days. As a result of acid aspiration, an increase was observed in the levels of serum clara cell protein-16 (CC-16) and advanced oxidation protein products, whereas there was a decrease in serum thiobarbituric acid-reactive substances, superoxide dismutase (SOD), and catalase levels. There was a significant decrease in peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar edema, and alveolar exudate scores, except in the alveolar histiocytes in the HCl + QC group. The expression of nitric oxide synthase, which increased after aspiration in the HCl group, showed a statistically significant decrease after the QC treatment. After the treatment with QC, an increase in the serum SOD level was observed, whereas a significant decrease was determined in the serum CC-16 level relative to that of the aspiration group (HCl). The antioxidant QC is effective in the treatment of lung injury following acid aspiration and can be used as a serum CC-16 biomarker in predicting the severity of oxidative lung injury.  相似文献   
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Essential thrombocythemia (ET) is an entity of classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), characterized by thrombocytosis with megakaryocytic hyperplasia and thrombocytes are increased with abnormal functions. Discovery of the protein tyrosine kinase JAK2 V617F allele contributed to better understanding of the pathogenetic mechanisms of MPNs. Acquired single point mutation in the JAK2 V617F was determined approximately 50–60 % of patients with ET. In this study we aimed to investigate the relationship between JAK2 V617F gene mutation, hematologic, biochemical markers and the complications in the ET patients. A total of 268 patients diagnosed with ET and 219 of those studied for JAK2 gene mutation were followed at the hematology clinics of three major hospitals between 2008 and 2013 were screened retrospectively. Laboratory, clinical and hematologic parameters were compared for JAK2 V617F positive and JAK2 V617F negative patients with ET. 102 (46 %) patients were positive with the JAK2 V617F mutation. The complications were observed in 61 (28 %) patients and 38 (62 %) of them had JAK2 V617F mutation. The levels of white blood cells, neutrophil, basophil, red blood cells, hemoglobin, hematocrit, mean platelet volume, thrombocytes, eosinophil; urea, creatinine were significantly different in patients with the JAK2 V617F mutation (P < 0.05). Presence of the JAK2 V617F mutation supports the diagnosis of ET. It would be useful to investigate the JAK2 V617F mutation and the hematologic and biochemical markers at diagnosis with respect to consider the risk of developing complications and to take the precautions against these complications.  相似文献   
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The purpose of this in vitro study was to determine the ability of seeded and not-seeded commercial pediatric blood culture bottles to support the growth of the most frequently responsible microorganisms for bacterial meningitides (Neisseria meningitidis, and Haemophilus influenzae). Tests have been carried out with an automated colorimetric pediatric blood culture system, BacTAlert, Organon Teknika. Bottles were inoculated with X-V factors and serial dilutions of the each bacterium in six times (10(1)-10(6) colony forming unit [CFU]/ml). The bottles, which were supplemented with X-V factors, proved to be effective and time to detection (TTD) was shorter than the un-seeded bottles (p0.05). Time difference between seeded and not-seeded bottles was getting greater at high dilutions of both bacteria. We consider that in presence of a few bacteria, the seeding of bottles with X-V factors is very critical obtaining N. meningitidis, and H. influenzae as the causative agents of meningitidis. The recovery rate of the microorganisms, which were isolated from cerebrospinal fluid by using the X-V factor-seeded blood culture bottles, is therefore higher than with the conventional culture methods.  相似文献   
239.
ProjectThe aim of the study was to investigate the serum reference range for Selenium (Se), Zinc (Zn) and Copper (Cu) levels in women of 10–14 (group I) and 16–20 (group II) weeks of gestation and compare them with those in non-pregnant healthy women and healthy men.ProcedureThis cross-sectional study was performed in 351 pregnant women [group I (n: 177) and group II (n: 174)], 30 non-pregnant women and 30 men as controls. The levels of Se, Zn and Cu levels were determined on flame and furnace atomic absorption spectrophotometer using Zeeman background correction.ResultsIn the 10–14 weeks of gestation Se, Zn and Cu serum levels were 44.85±9.23, 81.30±31.94 and 132.33±38.24 ug/dl, in 16–20 weeks of gestation were 47.18±10.92, 74.25±22.47 and 164.86±39.69 ug/dl, in non-pregnant women were 55.38±8.81, 121.41±29.22 and 104.75±39.14 ug/dl also in men 72.24±9.28, 134.85±15.95 and 78.29±20.90 ug/dl, respectively.ConclusionA significant low level of serum Se, Zn and a high level of Cu in the pregnant women in the 10–14 and 16–20 weeks of gestation were detected when compared with that of non-pregnant women and men.  相似文献   
240.
The effects of plant growth promoting rhizobacteria (PGPR) on the rooting and root growth of semi-hardwood and hardwood kiwifruit stem cuttings were investigated. The PGPR used were Bacillus RC23, Paenibacillus polymyxa RC05, Bacillus subtilis OSU142, Bacillus RC03, Comamonas acidovorans RC41, Bacillus megaterium RC01 and Bacillus simplex RC19. All the bacteria showed indole-3-acetic acid (IAA) producing capacity. Among the PGPR used, the highest rooting ratios were obtained at 47.50% for semi-hardwood stem cuttings from Bacillus RC03 and Bacillus simplex RC19 treatments and 42.50% for hardwood stem cuttings from Bacillus RC03. As well, Comamonas acidovorans RC41 inoculations indicated higher value than control treatments. The results suggest that these PGPR can be used in organic nursery material production and point to the feasibility of synthetic auxin (IBA) replacement by organic management based on PGPR.  相似文献   
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