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101.
Acute mesenteric ischemia (AMI) is a life-threatening emergency with prognosis directly correlated with the delay in diagnosis and treatment. Clinical and laboratory findings are nonspecific and it is imperative to look for findings of AMI on CT and ultrasound examinations performed in patients with acute abdomen. Arterial and venous ischemia are different entities with different clinical and imaging features, treatment and prognosis. The main causes of AMI are arterial thromboembolic disease and low-flow state. Venous ischemia is less frequent. Due to its high reported sensitivity (90%), CT should be performed as a firstline imaging modality when AMI is suspected. CT and ultrasound imaging features of AMI include: bowel wall thickness and enhancement abnormalities, pneumatosis, portal venous gas, demonstration of intravascular thrombus, bowel dilatation and ascitis.  相似文献   
102.
PURPOSE: To assess the value of MRCP in the detection of biliary complications after orthotopic liver transplantation. MATERIALS AND METHODS: 27 transplanted patients with suspected biliary complication underwent a total of 34 MR and direct cholangiography procedures. MRCP were reviewed by 2 independent reviewers blinded to clinical and laboratory findings. The biliary tract was divided into 7 segments, and all lesions were evaluated using this segmental anatomy. Each segment was evaluated for the presence of dilatation, stenosis and intra-ductal debris. MRCP results were compared to results frpm direct cholangiography. RESULTS: 216 (98%) of 221 biliary segments could be evaluated on MRCP, with good to excellent visualization in 179 (80%) cases. Segmental analysis showed sensitivity, specificity and accuracy values of 85%, 81% and 83% for the detection of biliary stenosis, 82%, 81% and 81% for the detection of biliary dilatation, and 60%, 88% and 80% for the detection of inyraductal debris. CONCLUSION: MRCP is accurate for the detection of biliary stenosis and dilatation in patients after liver transplantation and provides an alternative to direct cholangiography.  相似文献   
103.
PRPS1 codes for the enzyme phosphoribosyl pyrophosphate synthetase-1 (PRS-1). The spectrum of PRPS1-related disorders associated with reduced activity includes Arts syndrome, Charcot–Marie–Tooth disease-5 (CMTX5) and X-linked non-syndromic sensorineural deafness (DFN2). We describe a novel phenotype associated with decreased PRS-1 function in two affected male siblings. Using whole exome and Sanger sequencing techniques, we identified a novel missense mutation in PRPS1. The clinical phenotype in our patients is characterized by high prenatal maternal α-fetoprotein, intrauterine growth restriction, dysmorphic facial features, severe intellectual disability and spastic quadraparesis. Additional phenotypic features include macular coloboma-like lesions with retinal dystrophy, severe short stature and diabetes insipidus. Exome sequencing of the two affected male siblings identified a shared putative pathogenic mutation c.586C>T p.(Arg196Trp) in the PRPS1 gene that was maternally inherited. Follow-up testing showed normal levels of hypoxanthine in urine samples and uric acid levels in blood serum. The PRS activity was significantly reduced in erythrocytes of the two patients. Nucleotide analysis in erythrocytes revealed abnormally low guanosine triphosphate and guanosine diphosphate. This presentation is the most severe form of PRPS1-deficiency syndrome described to date and expands the spectrum of PRPS1-related disorders.  相似文献   
104.
Fetal erythropoiesis following bone marrow transplantation   总被引:5,自引:2,他引:5  
"Fetal" erythrocytes are present in older children and certain adults with hematologic disorders. To determine if regenerating bone marrow produces such cells, we examined the blood of seven allogeneic bone marrow transplant recipients. Six patients were engrafted with donor cells, while on e patients recovered autologous bone marrow after rejection of a marrow transplant. All seven patients had fetal hemoglobin levels of up to 10% by 100 days after transplant. In three patients, the Ggamma to Agamma ratio in the fetal hemoglobin was "newborn", while in one it was "adult". Gamma chain synthesis in blood and bone marrow never exceeded 20% of total non-alpha globin synthesis. The fetal hemoglobin was heterogeneously distributed in the cells. High titer i antigen also appeared. All fetal characteristics declined by 200 days. Erythropoiesis during bone marrow recovery appears to be associated with an accelerated, albeit partial, recapitulation of ontogeny.  相似文献   
105.
Beyond the acute posttransplantation period, glomerular causes of proteinuria in the renal allograft include recurrent glomerulopathy, transplant-associated entities, and de novo disease. We present a case of de novo minimal change disease with reversible acute renal failure occurring 2.5 years posttransplantation in a 56-year-old man. The cause of end-stage renal disease in the native kidney was membranous glomerulopathy. De novo minimal change disease in the renal allograft is an extremely rare entity requiring stringent clinical-pathological criteria for diagnosis. Many of the cases previously reported as de novo minimal change disease fail to meet these criteria. We review the eight reported cases that appear to fulfill a strict definition of minimal change disease in the context of the current report.  相似文献   
106.
Hemodialysis hypotension (HH) is a very common disorder and has a multifactorial etiology. Autonomic dysfunction occurs in up to 50% of patients with end-stage renal disease (ESRD) and plays a key role in HH in some patients. Sertraline hydrochloride, a central nervous system serotonin reuptake inhibitor, has been shown to be an effective treatment of hypotension caused by autonomic dysfunction in disorders such as neurocardiogenic syncope and idiopathic orthostatic hypotension. This study sought to determine whether sertraline was effective in ameliorating HH. A retrospective chart analysis was performed that included nine consecutive patients (aged > or = 54 years, time on hemodialysis > or = 2.2 years) placed on sertraline (50 to 100 mg/d) for depression who also had HH (defined as prehemodialysis systolic blood pressure [SBP] < or = 100 mm Hg, > or = 40 mm Hg decrease in SBP during hemodialysis, SBP <90 mm Hg, any diastolic blood pressure <40 mm Hg, or a decrease in blood pressure-causing symptoms) before treatment with sertraline. The data from a 6-week pre-sertraline period were compared with the data from a 6-week sertraline period (defined as 6 weeks after drug begun). Blood pressure medications were unchanged during the trial period of sertraline. However, nadir mean arterial pressure recorded during a given dialysis session in the pre-sertraline period (55+/-4 mm Hg) was significantly lower than that recorded in the sertraline period (68+/-5 mm Hg; P < 0.05). In addition, the number of hypotensive episodes (same definition as HH) per dialysis session during the sertraline period was significantly lower than that during the pre-sertraline period (mean, 0.6+/-0.2 episodes per session v 1.4+/-0.3 episodes per session; P < 0.005). The number of therapeutic interventions required for hypotension during the sertraline period was also significantly less than that during the pre-sertraline period (mean, 1.7+/-0.8 interventions v 11.0+/-3.0 interventions; P < 0.005). The urea reduction ratio (62.7%+/-4.7% v 63.1%+/-9.3%; P = NS) and hematocrit (28.9%+/-0.8% v 29.5%+/-1.0%; P = NS) did not change significantly. It is concluded that the short-term (6 weeks) use of sertraline hydrochloride reduces HH in some patients with ESRD. A possible mechanism for this effect is sertraline-induced attenuation of the paradoxical sympathetic withdrawal that may underlie HH in some patients with ESRD.  相似文献   
107.
108.
Members of 7 large families, containing 20 patients with sickle cell anemia (SS) characterized by high levels of fetal hemoglobin (HbF), were studied using immunofluorescence to count F cells and a radioimmunoassay to measure small amounts of HbF. In five of these families, one of the sickle cell trait (AS) parents had a much higher HbF and F-cell count than the other; in one family, both parents had a marked increase in HbF and F cells; in the remaining family, HbF and F cells were at borderline values in both parents. Seven of 14 AS siblings, but only 1 of 8 normal hemoglobin (AA) siblings, also had HbF and F-cell counts above the "normal" range. It seems that a factor for increased F cells, linked to the beta S gene of one parent, is segregating in these families and is responsible for the greatly increased HbF and F cells in the SS subjects. HbF per F cell in AS parents and siblings was the same as that of normal AA subjects, whereas in the SS offspring it was greatly increased, suggesting that it was the result of marrow hyperplasia associated with their hemolytic anemia. The similarity of this "increased F-cell gene" to heterocellular hereditary persistence of fetal hemoglobin (HPFH). Swiss type, is discussed, and it is suggested that it may control the persistent synthesis of HbF in sickle cell anemia by its presence in early infancy.  相似文献   
109.
To determine whether hemoglobin regulation is normal in diseases affecting beta-globin gene expression, globin synthesis was examined in members of a family of a patient with hereditary persistence of fetal hemoglobin/beta o-thalassemia (HPFH/beta o-thal). The HPFH defect is the Ghanian type II, with a deletion from psi beta 1 to at least 20 kb 3' to beta. The beta o-thal gene has the haplotype II restriction enzyme pattern and has the beta 39 nonsense mutation. Erythroid colonies from blood BFU-E were radiolabeled, and globin chains were separated by gel electrophoresis. Colonies from the beta o-thal heterozygote had non-alpha/alpha ratios more balanced than in the reticulocytes. Gamma synthesis was 11% of non-alpha, which is higher than in reticulocytes, but within the range seen in normal adult colonies. Both HPFH heterozygotes produced 20%-30% gamma in erythroid colonies as well as reticulocytes, although non-alpha/alpha was more balanced in the colonies. The HPFH/beta o-thal patient produced 100% gamma in reticulocytes and in colonies. G gamma and gamma-synthetic proportions were not correlated at the individual colony level in the heterozygotes, suggesting that they had "adult" and not "fetal" progenitor cells. The Hb expression of these adult progenitors is presumably modulated normally in vivo in beta o-thal, but the normal decrease in HbF production does not occur in gene deletion HPFH.  相似文献   
110.

Objectives

Right hemicolectomy is a common colorectal operation for resection of cancers of the right colon. The ileocolic anastomosis may be created using a stapled end-to-side, stapled side-to-side or handsewn technique. Anastomotic leak and post-operative bleeding are uncommon but serious causes of morbidity and mortality, while post-operative ileus contributes to prolonged length of stay. The aim of this study was to evaluate differences in short-term outcomes between different anastomotic configurations following right hemicolectomy for colon cancer.

Methods

We conducted a retrospective study using data from the Bowel Cancer Outcomes Registry (BCOR), including 94 hospitals across Australia and New Zealand, of all patients who underwent right hemicolectomy or extended right hemicolectomy for colon cancer with formation of a primary anastomosis between 2007 and 2021.

Results

We included 8164 patients in the analysis. There was no significant difference in rates of anastomotic leak and anastomotic bleeding based on anastomotic technique. A stapled end-to-side anastomosis was associated with a lower rate of post-operative ileus than stapled side-to-side anastomosis (6.5% vs. 7.2%; P = 0.03).

Conclusion

Both handsewn and stapled anastomosis techniques may be utilized for oncologic right hemicolectomy, with comparable rates of anastomotic leak and post-operative bleeding. Stapled end-to-side anastomosis resulted in lower rates of prolonged ileus compared to stapled side-to-side anastomoses.  相似文献   
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