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1.
The renin-aldosterone axis in patients with diabetes insipidus   总被引:1,自引:1,他引:0  
OBJECTIVE The objective of the present study was to investigate the renin-aldosterone axis in neurogenic diabetes insipidus in man, in view of the fact that profound abnormalities of this axis have been described in experimental animals with congenital neurogenic diabetes insipidus. DESIGN AND PATIENTS Nine patients with neurogenic diabetes insipidus and 11 healthy subjects (controls) were examined under basal conditions, following the standard 8-hour water deprivation test and 1 hour after a subsequent oral rehydration. MEASUREMENTS Plasma and urine osmolalities were determined by freezing point depression, plasma sodium and potassium by a method using an ion-selective electrode, plasma AVP, Cortisol, aldosterone and plasma renin activity by radioimmunoassay. RESULTS Plasma renin activities under basal conditions were significantly higher in patients with diabetes insipidus than in controls (mean ± SEM 23.4 ± 6.6 vs 7.8 ± 1.2 ng/ I min). In the diabetes insipidus group, water deprivation caused a twofold Increase in plasma renin activities (48 ± 13.8 ng/l min), while in the control group plasma renin activity levels were not significantly altered (10.2 ± 1.2 ng/l min). Rehydration did not alter plasma renin activity levels in either group (patients 50.4 ± 13.2, controls 9.0 ± 2.4 ng/l min). Plasma aldosterone concentrations under basal conditions did not differ between the two groups (patients 302.4 ± 37, controls 326.4 ± 36.5 pmol/l) and did not change in patients with diabetes insipidus after water deprivation or rehydration (307.5 ± 67.2 and 385.5 ± 91 pmol/l, respectively). Conversely, controls showed a significant decrease in plasma aldosterone levels after dehydration (201 ± 27.9 pmol/l), which was attributed to the circardian variation in aldosterone secretion, as shown by a parallel decrease in plasma Cortisol levels. CONCLUSIONS Patients with diabetes insipidus are hyper-reninaemic, probably because of chronic volume contraction. There is a dissociation between renin and aldosterone in patients with diabetes insipidus under basal conditions, which is exaggerated during water deprivation.  相似文献   
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DNA and FISH (fluorescence in situ hybridization) analysis were carried out in 12 patients with stigmata of Turner syndrome to determine whether the Supernumerary M arker C hromosome (SMC) found cytogenetically in each of these patients was derived from the Y chromosome. The presence of a Y chromosome in these patients may predispose them to develop gonadoblastoma. PCR-Southern blot analysis, followed by FISH, was used to detect the presence of Y chromosome material. The S ex determining R egion Y (SRY), T estis S pecific P rotein Y -encoded (TSPY) and Y -chromosome R NA R ecognition M otif (YRRM) genes, which map at Yp11.31, Yp11.1–11.2 and Yp11.2/Yq11.21–11.23, respectively, were selected as markers, because they span the whole Y chromosome, and more importantly, they are considered to be involved in the development of gonadoblastoma. It was shown that in 12 patients, all of whom had an SMC, the SMC of 11 was derived from the Y chromosome. Furthermore, the presence of the SRY, TSPY and YRRM gene sequences was determined and FISH analysis confirmed the Y origin of the SMCs. The methodology described in this report is a rapid, reliable and sensitive approach which may be easily applied to determine the Y origin of an SMC carried in Turner syndrome. The identification of an SMC is important for the clinical management and prognostic counseling of these patients with Turner syndrome.  相似文献   
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The presence of Y chromosome sequences in Turner syndrome (TS) patients may predispose them to gonadoblastoma formation with an estimated risk of 15–25%. The aim of this study was to determine the presence and the incidence of cryptic Y chromosome material in the genome of TS patients. The methodology involved a combination of polymerase chain reaction (PCR) and nested PCR followed by Southern blot analysis of three genes—the sex determining region Y (SRY), testis specific protein Y encoded (TSPY) and RNA binding motif protein (RBM) (previously designated as YRRM) and nine additional STSs spanning all seven intervals of the Y chromosome. The methodology has a high sensitivity as it detects one 46, XY cell among 105 46, XX cells. Reliability was ensured by taking several precautions to avoid false positive results. We report the results of screening 50 TS patients and the identification of cryptic Y chromosome material in 12 (24%) of them. Karyotypes were divided in four groups: 5 (23.8%) patients out of the 21 TS patients which have the 45, X karyotype (group A) also have cryptic Y sequences; none (0%) of the 7 patients who have karyotypes with anomalies on one of the X chromosomes have Y mosaicism (group B); 1 (6.3%) of the 16 patients with a mosaic karyotype have Y material (group C); and 6 (100%) out of 6 patients with a supernumerary marker chromosome (SMC) have Y chromosome sequences (group D). Nine of the 12 patients positive for cryptic Y material were recalled for a repeat study. Following new DNA extraction, molecular analysis was repeated and, in conjunction with fluorescent in situ hybridization (FISH) analysis using the Y centromeric specific probe Yc-2, confirmed the initial positive DNA findings. This study used a reliable and sensitive methodology to identify the presence of Y chromosome material in TS patients thus providing not only a better estimate of a patient's risk in developing either gonadoblastoma or another form of gonadal tumor but also the overall incidence of cryptic Y mosaicism.  相似文献   
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Growing evidence suggests that sleep could affect the immunological response after vaccination. The aim of this prospective study was to investigate possible associations between regular sleep disruption and immunity response after vaccination against coronavirus disease 2019 (COVID-19). In total, 592 healthcare workers, with no previous history of COVID-19, from eight major Greek hospitals were enrolled in this study. All subjects underwent two Pfizer–BioNTech messenger ribonucleic acid (mRNA) COVID-19 vaccine BNT162b2 inoculations with an interval of 21 days between the doses. Furthermore, a questionnaire was completed 2 days after each vaccination and clinical characteristics, demographics, sleep duration, and habits were recorded. Blood samples were collected and anti-spike immunoglobulin G antibodies were measured at 20 ± 1 days after the first dose and 21 ± 2 days after the second dose. A total of 544 subjects (30% males), with median (interquartile range [IQR]) age of 46 (38–54) years and body mass index of 24·84 (22.6–28.51) kg/m2 were eligible for the study. The median (IQR) habitual duration of sleep was 6 (6–7) h/night. In all, 283 participants (52%) had a short daytime nap. In 214 (39.3%) participants the Pittsburgh Sleep Quality Index score was >5, with a higher percentage in women (74·3%, p < 0.05). Antibody levels were associated with age (r = −0.178, p < 0.001), poor sleep quality (r = −0.094, p < 0.05), insomnia (r = −0.098, p < 0.05), and nap frequency per week (r = −0.098, p < 0.05), but after adjusting for confounders, only insomnia, gender, and age were independent determinants of antibody levels. It is important to emphasise that insomnia is associated with lower antibody levels against COVID-19 after vaccination.  相似文献   
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PURPOSE: We analyzed the benefits of a risk-adapted postremission strategy in adult lymphoblastic leukemia (ALL), and re-evaluated stem-cell transplantation (SCT) for high-risk ALL. PATIENTS AND METHODS: A total of 922 adult patients entered onto the trial according to risk groups: standard-risk ALL (group 1), high-risk ALL (group 2), Philadelphia chromosome-positive ALL (group 3), and CNS-positive ALL (group 4). All received a standard four-drug/4-week induction course. Patients from group 1 who achieved a complete remission (CR) after one course of induction therapy were randomly assigned between intensive and less intensive postremission chemotherapy, whereas those who achieved CR after salvage therapy were then included in group 2. Patients in groups 2, 3, and 4 with an HLA-identical sibling were assigned to allogeneic SCT. In groups 3 and 4, autologous SCT was offered to all other patients, whereas in group 2 they were randomly assigned between chemotherapy and autologous SCT. RESULTS: Overall, 771 patients achieved CR (84%). Median disease-free survival (DFS) was 17.5 months, with 3-year DFS at 37%. In group 1, the 3-year DFS rate was 41%, with no difference between arms of postremission randomization. In groups 2 and 4, the 3-year DFS rates were 38% and 44%, respectively. In group 2, autologous SCT and chemotherapy resulted in comparable median DFS. Patients with an HLA-matched sibling (groups 2 and 4) had improved DFS. Three-year DFS was 24% in group 3. CONCLUSION: Allogeneic SCT improved DFS in high-risk ALL in the first CR. Autologous SCT did not confer a significant benefit over chemotherapy for high-risk ALL.  相似文献   
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Microbiota composition and associated metabolic activities are essential for the education and development of a healthy immune system. Microbial dysbiosis, caused by risk factors such as diet, birth mode, or early infant antimicrobial therapy, is associated with the inception of allergic diseases. In turn, allergic diseases increase the risk for irrational use of antimicrobial therapy. Microbial therapies, such as probiotics, have been studied in the prevention and treatment of allergic diseases, but evidence remains limited due to studies with high heterogeneity, strain-dependent effectiveness, and variable outcome measures. In this review, we sketch the relation of microbiota with allergic diseases, the overuse and rationale for the use of antimicrobial agents in allergic diseases, and current knowledge concerning the use of bacterial products in allergic diseases. We urgently recommend 1) limiting antibiotic therapy in pregnancy and early childhood as a method contributing to the reduction of the allergy epidemic in children and 2) restricting antibiotic therapy in exacerbations and chronic treatment of allergic diseases, mainly concerning asthma and atopic dermatitis. Future research should be aimed at antibiotic stewardship implementation strategies and biomarker-guided therapy, discerning those patients that might benefit from antibiotic therapy.  相似文献   
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AIM:To determine end-stage pathologic changes in the liver of septic patients dying in the intensive care unit.
METHODS: Needle liver biopsies obtained immediately after death from 15 consecutive patients with sepsis and no underlying liver disease were subjected to routine histological examination. Liver function tests and clinical monitoring measurements were also recorded.
RESULTS: Liver biochemistries were increased in the majority of patients before death. Histology of liver biopsy specimens showed portal inflammation in 73.3%, centrilobular necrosis in 80%, lobular inflammation in 66.7%, hepatocellular apoptosis in 66.6% and cholangitis/cholangiolitis in 20% of patients. Mixed hepatitic/ cholestatic type of liver injury was observed in 6/15 (40%) patients and hepatitc in 9/15 (60%). Steatosis was observed in 11/15 (73.3%) patients affecting 5%-80% of liver parenchyma. Among the histological features, the presence of portal inflammation in liver biopsy was associated with increased hospitalization in the ICU prior death (P = 0.026).
CONCLUSION: Features of hepatitis and steatosis arethe main histological findings in the liver in the majority of patients dying from sepsis.  相似文献   
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Preimplantation genetic diagnosis (PGD) for monogenic disorders currently involves polymerase chain reaction (PCR)-based methods, which must be robust, sensitive and highly accurate, precluding misdiagnosis. Twelve adverse misdiagnoses reported to the ESHRE PGD-Consortium are likely an underestimate. This retrospective study, involving six PGD centres, assessed the validity of PCR-based PGD through reanalysis of untransferred embryos from monogenic-PGD cycles. Data were collected on the genotype concordance at PGD and follow-up from 940 untransferred embryos, including details on the parameters of PGD cycles: category of monogenic disease, embryo morphology, embryo biopsy and genotype assay strategy. To determine the validity of PCR-based PGD, the sensitivity (Se), specificity (Sp) and diagnostic accuracy were calculated. Stratified analyses were also conducted to assess the influence of the parameters above on the validity of PCR-based PGD. The analysis of overall data showed that 93.7% of embryos had been correctly classified at the time of PGD, with Se of 99.2% and Sp of 80.9%. The stratified analyses found that diagnostic accuracy is statistically significantly higher when PGD is performed on two cells versus one cell (P=0.001). Se was significantly higher when multiplex protocols versus singleplex protocols were applied (P=0.005), as well as for PGD applied on cells from good compared with poor morphology embryos (P=0.032). Morphology, however, did not affect diagnostic accuracy. Multiplex PCR-based methods on one cell, are as robust as those on two cells regarding false negative rate, which is the most important criteria for clinical PGD applications. Overall, this study demonstrates the validity, robustness and high diagnostic value of PCR-based PGD.  相似文献   
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