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51.
Left ventricular function was evaluated by first-pass radionuclide angiocardiography in 42 patients at 3 and 8 weeks following acute myocardial infarction. Left ventricular ejection fraction, diastolic volume, and wall motion were measured at rest and submaximal exercise at 3 weeks and at rest, submaximal and maximal exercise at 8 weeks. The mean ejection fraction, end-diastolic volume, and wall motion index did not change between 3 and 8 weeks in any group either at rest or during submaximal exercise. Ventricular function was decreased at rest in patients with previous and anterior myocardial infarction, but not in patients with inferior and subendocardial myocardial infarctions. During maximal exercise at 8 weeks, nine patients (21%) had ST segment depression, whereas 25 patients (60%) had a decrease in ejection fraction or a deterioration in wall motion. These abnormalities of ventricular function during exercise occurred equally among the infarct groups. Radionuclide angiography in patients with recent myocardial infarction demonstrated highly variable ventricular function at rest and/or during exercise in each infarct subgroup.  相似文献   
52.
Cu2Se, owing to its intrinsic excellent thermoelectric (TE) performance emerging from the peculiar nature of “liquid-like” Cu+ ions, has been regarded as one of the most promising thermoelectric materials recently. However, the commercial use is still something far from reach unless effective approaches can be applied to further increase the figure of merit (ZT) of Cu2Se, and doping has shown wide development prospect. Until now, the highest ZT value of 2.62 has been achieved in Al doped samples, which is twice as much as the original pure Cu2Se. Herein, various doping elements from all main groups and some transitional groups that have been used as dopants in enhancing the TE performance of Cu2Se are summarized, and the mechanisms of TE performance enhancement are analyzed. In addition, points of great concern for further enhancing the TE performance of doped Cu2Se are proposed.  相似文献   
53.
OBJECTIVE: The purpose of the study was to assess patterns of primary pancreatic lesions by contrast-enhanced sonography for differentiating ductal carcinomas from other pancreatic tumors. METHODS: One hundred six consecutive patients with pancreatic masses, consisting of 83 ductal carcinomas, 7 endocrine carcinomas, 5 intraductal papillary mucinous tumors, 3 cases of autoimmune-related pancreatitis, 3 solid pseudopapillary tumors, 2 cases of chronic pancreatitis, 1 serous cystadenoma, 1 osteoclastoid giant cell tumor, and 1 follicular lymphoma, were examined by contrast-enhanced sonography with coded harmonic imaging in a phase inversion harmonic technique. The contrast enhancement patterns were assessed, and specimens removed during pancreatectomy were subjected to pathologic examination. RESULTS: Internal tumoral vascularity was detected in 47 (56.6%) of the 83 ductal carcinomas. Vascular image spreading and homogeneous staining throughout the tumors were observed in all endocrine carcinomas. Two of the 5 intraductal papillary mucinous tumors were positive for enhancement effects. Enhancement effects were observed in all 3 cases of autoimmune-related pancreatitis, but the degree varied. There was a significant correlation between the intensity of enhancement effects and the ratio of patent vessels in the tumors (P < .05). CONCLUSIONS: Vascularity was detected by contrast-enhanced sonography in only about half of the ductal carcinomas, confirming the difficulty in distinguishing those tumors from other pancreatic tumors. There was a correlation between the patency of the vessels in the tumors and their vascularity.  相似文献   
54.
The effects of oral prazosin (PZ), 15 to 20 mg/day, on symptoms, exercise performance and left ventricular (LV) function were assessed in a 6-month, double-blind, placebo-controlled study of patients in New York Heart Association functional class III. Ejection fraction (EF) was measured at rest and during upright bicycle exercise by equilibrium radionuclide angiography; end-diastolic volume, stroke volume and cardiac output were derived from corresponding count measurements. Although there was no statistically significant difference between clinical responses in the prazosin and placebo groups, qualitative differences suggested a clinical response to prazosin. Of the 9 patients who received PZ, 5 improved to functional class II and 2 became asymptomatic; the 2 nonresponders deteriorated to functional class IV when PZ was stopped. Four of 9 patients who received placebo improved to functional class II and 2 deteriorated to class IV. Exercise time tended to increase in the prazosin group (from 541 ± 204 to 630 ±100 seconds at 6 months) and decrease in the placebo group (from 539 ± 141 to 435 ±148 seconds at 6 months), but neither change was significant. Prazosin effected a sustained decrease in mean blood pressure of approximately 10 mm Hg at rest, and a quantitatively similar but insignificant decrease during exercise. Radionuclide EF increased and LV end-diastolic counts decreased significantly at rest and during exercise in the prazosin group, but not in the placebo group. Because changes in EF and end-diastolic counts were similar, stroke counts and count output were unchanged. Thus, long-term oral PZ therapy caused sustained changes in blood pressure and LV function in most patients in functional class III, but these changes were not uniformly translated into clinical improvement or increased exercise tolerance. Prazosin does not appear to increase cardiac output during exercise in patients with heart failure.  相似文献   
55.
Objective : To determine the genotype of patients attending the cystic fibrosis clinic at John Hunter Hospital, Newcastle, Australia.
Methodology : Seventy-five of the 76 patients attending the clinic over a 6 month period had blood collected for genetic analysis of 17 of the cystic fibrosis (CF) gene mutations.
Results : Sixty-one per cent of the patients were homozygous for the ΔF508 mutation and all except one child had at least one ΔF508 mutation.
Discussion : Nearly 80% of the CF genes were the ΔF508 mutation. This prevalence suggests that the obligatory false negative rate of a newborn screening programme for CF based on a combination of immunoreactive trypsin and the ΔF508 gene may be as low as 4-5%.  相似文献   
56.
M.   zgü    A. Tekin  H. Erdem  E. Y&#x  lmaz    . Ayter  T. Co  kun  A. Can  S. G        M.   aglar  G. Kale  Z. Ak    ren 《Fetal and pediatric pathology》1994,14(3):491-496
Incidence of ΔF508, a severe mutation of the CFTR gene is found to be 36.3% in paraffin block cystic fibrosis liver tissues. Samples are histologically grouped according to severity of pancreatic involvement. Two families where ΔF508 was detected postmortem and who have no living children, will have the chance for a prenatal diagnosis in the future pregnancies.  相似文献   
57.
Carbohydrate intolerance and frank diabetes mellitus (DM) are recognised features of cystic fibrosis (CF), but their cause has not been established. Damage to the islet cells due to pancreatic fibrosis is the most common explanation. The relationship between the genotype and the occurrence of diabetes mellitus has been examined in 21 cystic fibrosis patients attending our out-patient chest clinics. DNA samples were tested for the presence of the most common mutation (AF508) and the results related to the degree of carbohydrate intolerance. We found that in CF patients over 18 years of age diabetes is more frequent among those homozygous for the AF508 allele than the heterozygotes (P < 0.05). Those homozygous for AF508 were diagnosed as CF at an earlier age than the heterozygotes (P < 0.05). Both the mean age and the female/male ratio were similar in the diabetic and non-diabetic groups. The prevalence of the AF508 allele was similar to that expected in a random sample of East Anglian cystic fibrosis patients. These data suggest that the occurrence of diabetes mellitus in patients with cystic fibrosis is related to the genotype, which could be secondary to the way the genetic factors influence the degree of pancreatic disease and its rate of progression.  相似文献   
58.
BackgroundAccurate and fast localization of small pulmonary nodules is required for local pulmonary resection. In this study, we introduced and assessed a novel technique for the preoperative localization of small pulmonary nodules by using ZT medical glue (2-octyl cyanoacrylate).Methods101 patients who had a combined total of 106 small pulmonary nodules located by ZT glue and 53patients with 53 small pulmonary nodules located by hookwire were selected. Guided by computed tomography (CT), the surgeon injected certain volume ZT glue into an area adjacent to the small pulmonary nodule, then, the adjacent lung tissue infiltrated by ZT glue formed into a depressed hard nodule which can be used for preoperative localization with an obvious mark on lung surface or different hand touch. After localization, Wedge resection was performed via video-assisted thoracoscopic surgery and the specimen obtained from the procedure was immediately sent for pathological examination, followed by a standard surgical procedure. A contrast has been made between the ZT glue method and the hookwire.Results101 operations were successfully performed by using this novel technique, and 106 small pulmonary nodules were successfully located. Compared with the hookwire location, ZT glue method obviouslyextended the Time interval between localization and operation (P = 0.00) and a same complication rate (P = 0.07).ConclusionsThe use of ZT glue is a safe and effective method for the localization of small pulmonary nodules.Trial registrationThis study was approved by the ethics committee of Shaoxing People's Hospital (Number:2016-004, Date:2016,2,24), and informed consent was obtained from all enrolled patients.  相似文献   
59.
We present a case of a multiple renal artery reconstruction during simultaneous pancreas and kidney transplantation. The kidney graft had 6 renal arteries, the aorta patch was 10 cm long, and there were two renal veins. To perform anastomoses to the left external iliac vessels we had to reconstruct the renal arterial and venal patches. The results of the transplantation were very good. Both grafts had satisfactory function, even though a control computed tomography performed a year after transplantation revealed infarction of a lower renal pole. Anatomical anomalies should not be a contraindication for transplantation, although transplants involving a multiplicity of vessels is a challenge for surgeons and requires both knowledge and microsurgical skills.  相似文献   
60.
BackgroundIn cystic fibrosis (CF), genotype-phenotype correlation is complicated by the large number of CFTR variants, the influence of modifier genes, environmental effects, and the existence of complex alleles. We document the importance of complex alleles, in particular the F508C variant present in cis with the S1251N disease-causing variant, by detailed analysis of a patient with CF, with the [S1251N;F508]/G542X genotype and a very mild phenotype, contrasting it to that of four subjects with the [S1251N;F508C]/F508del genotype and classical CF presentation.MethodsGenetic differences were identified by Sanger sequencing and CFTR function was quantified using rectal organoids in rectal organoid morphology analysis (ROMA) and forskolin-induced swelling (FIS) assays. CFTR variants were further characterised in CF bronchial epithelial (CFBE) cell lines. The impact of involved amino acid changes in the CFTR 3D protein structure was evaluated.ResultsOrganoids of the patient [S1251N;F508] with mild CF phenotype confirmed the CF diagnosis but showed higher residual CFTR function compared to the four others [S1251N;F508C]. CFBE cell lines showed a decrease in [S1251N;F508C]-CFTR function but not in processing when compared to [S1251N;F508]-CFTR. Analysis of the 3D CFTR structure suggested an additive deleterious effect of the combined presence of S1251N and F508C with respect to NBD1-2 dimerisation.ConclusionsIn vitro and in silico data show that the presence of F508C in cis with S1251N decreases CFTR function without affecting processing. Complex CFTR alleles play a role in clinical phenotype and their identification is relevant in the context of personalised medicine for each patient with CF.  相似文献   
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