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1.
Single and multiple cholesterol gallstones and the influence of bacteria   总被引:5,自引:0,他引:5  
Single and multiple cholesterol gallstones constitute at least 80% of the gallstone population observed at cholecystectomy in Western countries. While supersaturation of bile with cholesterol is necessary for gallstone growth, the kinetic determinant of crystal nucleation is perhaps the critical factor leading to the incidence of gallstones. Nucleation involves aggregation of nidus-forming materials like pigment precipitates and mucus proteins. In combination with cholesterol precipitates and crystal formation, gallstone propagation is enhanced. Bacterial species may augment the process of nucleation and gallstone growth by contributing specific enzyme activities resulting in the formation of insoluble precipitates in bile, or by acting as a nidus upon which the deposition of cholesterol crystals may initiate gallstone formation. The utilization of Raman microscopic techniques permits detailed mapping of the distribution of the gallstone components leading to identification and characterization of the site of nucleation. This, when coupled to molecular genetic tools such as PCR DNA amplification, would permit elucidation of the role of bacteria in vivo gallstone propagation mechanisms.  相似文献   
2.
Ecto‐nucleotide pyrophosphatase/phosphodiesterases (E‐NPPs) have been implicated in bone calcification, type II diabetes, control of purinergic signalling and tumour invasion. The gene for the plasma cell membrane glycoprotein PC‐1 in the mouse (Enpp1) has been known since 1970 to exist in two allelic forms, but their structural basis was heretofore unknown. We show that the Enpp1a and Enpp1b alleles differ by only two amino acids, at positions 650 and 679 in the C‐terminal nuclease‐like domain. Histidine 650 but not arginine 679 forms an essential part of the Enpp1a epitope recognized by monoclonal antibody IR‐518. Sequences of LEW and LOU rats and the rat glioma cell line C6 differ from that of the mouse by about 60 amino acids. The LOU and C6 cell line sequences differ by only three amino acids, but differ from the LEW sequence by 10 amino acids. All three rat strains possess the mouse Enpp1b allele at positions 650 and 679. Despite numerous other differences from the mouse, rats immunized with Enpp1a mouse cells have generated monoclonal antibodies specific for the Enpp1a allele, suggesting that amino acids 650 and 679 may be particularly immunogenic. The cytoplasmic tails of the mouse and rat are highly conserved, but are significantly different from human cytoplasmic tails.  相似文献   
3.
Several circulating Bacillus anthracis strains isolated in Italy and belonging to the A1.a cluster, genotype 3 (A1.a-3) are genotypically indistinguishable from Carbosap, a live attenuated vaccine strain, containing both pXO1 and pXO2 plasmids. The genotype was assessed by using eight-locus multilocus variable-number tandem repeat analysis. We describe here the use of a ninth locus able to explore variability among strains that have the same genotype. It is important to be able to genotype the wild isolate of B. anthracis strains from outbreaks of anthrax in areas where Carbosap vaccination of cattle and sheep is common practice. A total of 27 representative field strains isolated in Italy and four vaccinal strains, namely, Carbosap, Sterne, Pasteur I, and Pasteur II, were characterized by a ninth marker, called pXO2-A. Twenty-three field strains were genotype 3 and therefore identical to Carbosap. The marker was in the pXO2 plasmid and is based on the polymorphism of the already-known VX2-3 locus. Detection was obtained by PCR with fluorescence-labeled forward primers in order to produce appropriate fragments for capillary electrophoresis with an ABI 310 genetic analyzer. Genetic relationships showed heterogeneity in all of the examined samples. Interestingly, with respect to genotype 3, samples grouped into eight different subtypes, A to H, and the subtype G, had only two samples indistinguishable from Carbosap. The results of the present study confirm the validity of a hierarchical progressive protocol for discrimination among closely related isolates.  相似文献   
4.
5.
Parathyroid carcinoma (PC) is a rare malignancy that poses a diagnostic challenge on histologic examination. We analyzed various clinicopathologic features of PC. Pathology reports and slides were reviewed to evaluate the diagnostic histopathologic features of archived cases of PC from the years of 2004–2018. The study cohort comprised twenty cases of PC. The median age was 49 years (range 21–73 years) with equal gender distribution (M:F = 1:1). Most patients presented with symptoms of hypercalcemia (n = 7, 54%). Serum calcium and serum parathyroid hormone were elevated in all but one patient. The right inferior parathyroid was commonly involved (n = 8/14, 57%). The mean tumor size was 2.4 cm (range 0.8–3.5 cm). On frozen section examination, PC was diagnosed in 8 out of 9 cases. Vascular (n = 19/20, 95%) and soft tissue invasion (n = 10/20, 50%) were the most common characteristic histologic findings. Capsular invasion was identified in all cases. Perineural invasion or metastasis at presentation was absent in all cases. Other histological features noted were intratumoral fibrous bands (70%), nodular growth pattern (70%), moderate nuclear atypia (30%), prominent nucleoli (20%), and necrosis (20%). Regional lymph nodes were negative for metastatic disease in all cases (n = 10). Eight out of 16 patients received adjuvant radiotherapy. Follow-up was available in 16 cases (median 21.5 months). Two patients died of disease. Vascular and soft tissue invasion are the most common diagnostic histologic features of PC. Capsular invasion is important to distinguish PC from its benign counterparts. Intraoperative frozen section examination can be used for accurate diagnosis and surgical management.  相似文献   
6.
We report on an infant with multi-system disease including liver fibrosis, right microphthalmia with cataract, interstitial pneumonitis, and hyperechoic lesions in the basal ganglia and in the periventricular and thalamic regions. Prenatal ascites with hepatomegaly concomitantly with detection of cytomegalovirus (CMV) DNA in the amniotic fluid, following recurrent maternal CMV infection, had been shown. Although CMV culture and DNA detection were negative in the urine, the infant was given foscarnet because CMV infection was demonstrated in the liver by DNA detection and immunohistochemical staining. Favorable clinical outcome and absence of CMV in the liver were subsequently shown. Our case suggests that congenital CMV disease following maternal recurrence may not be associated with disseminated infection but only with intracellular infection. The diagnosis should therefore be based on CMV detection in the involved organs. Moreover, this is the first report on the possible efficacy and safety of foscarnet for therapy of immunocompetent infants with congenital CMV disease.  相似文献   
7.
Swine viral diseases challenge the sector’s sustainability by affecting productivity and the health and welfare of the animals. The lack of antiviral drugs and/or effective vaccines renders early and reliable diagnosis the basis of viral disease management, underlining the importance of point-of-care (POC) diagnostics. A novel POC diagnostic device utilizing photonic integrated circuits (PICs), microfluidics, and information and communication technologies for the detection of porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza A (SIV) was validated using spiked and clinical oral fluid samples. Metrics including sensitivity, specificity, accuracy, precision, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to assess the performance of the device. For PRRSV, the device achieved a sensitivity of 83.5%, specificity of 77.8%, and DOR values of 17.66, whereas the values for SIV were 81.8%, 82.2%, and 20.81, respectively. The POC device and PICs can be used for the detection of PRRSV and SIV in the field, paving the way for the introduction of novel technologies in the field of animal POC diagnostics to further optimize livestock biosecurity.  相似文献   
8.
Herpes Simplex Virus type 1 (HSV‐1) is a very common infection often localized in the mucocutaneous junction of the lip. Rarely, it could be detected also in periodontal tissues, associated with an elevated risk of periodontal disease progression and gingival recessions. Recently, HSV‐1 and numerous co‐infections have been reported in literature associated with the Coronavirus and subsequent COVID‐19 disease. This report illustrates a case of HSV‐1 in a patient with Covid‐19 infection, showing the presence of ulcers and vesicles on the gingival margin of maxillary teeth associated with soreness and pain. The histology highlighted the presence of intraepithelial cell ballooning, confirming the diagnosis of HSV‐1 infection.  相似文献   
9.
10.
Dietary interventions may have the potential to counter age-related cognitive decline. Studies have demonstrated an improvement in age-related cognitive impairment in animals after supplementation with plant extracts containing flavonoids but there are few human studies. This double-blind, controlled study examined the effects on cognitive performance of a 5 week supplementation with Enzogenol Pinus radiata bark extract containing flavonoids, in 42 males aged 50-65 years, with a body mass index >25. Participants were supplemented for 5 weeks either with Enzogenol plus vitamin C, or with vitamin C only. A battery of computerized cognitive tests was administered, and cardiovascular and haematological parameters were assessed prior to and following supplementation. The speed of response for the spatial working memory and immediate recognition tasks improved after supplementation with Enzogenol plus vitamin C, whereas vitamin C alone showed no improvements. A trend in a reduction of systolic blood pressure was observed with Enzogenol plus vitamin C, but not with vitamin C alone. The blood safety parameters were unchanged. The findings suggest a beneficial effect of supplementation with Enzogenol on cognition in older individuals. Larger studies are needed to ascertain its potential as a preventive treatment for age-related cognitive decline.  相似文献   
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