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21.
Helicobacter pylori (H. pylori) infection is highly prevalent in human, affecting nearly half of the world’s population; however, infection remains asymptomatic in majority of population. During its co-existence with humans, H. pylori has evolved various strategies to maintain a mild gastritis and limit the immune response of host. On the other side, presence of H. pylori is also associated with increased risk for the development of various gastric pathologies including gastric cancer (GC). A complex combination of host genetics, environmental agents, and bacterial virulence factors are considered to determine the susceptibility as well as the severity of outcome in a subset of individuals. GC is one of the most common cancers and considered as the third most common cause of cancer related death worldwide. Many studies had proved H. pylori as an important risk factor in the development of non-cardia GC. Although both H. pylori infection and GC are showing decreasing trends in the developed world, they still remain a major threat to human population in the developing countries. The current review attempts to highlight recent progress in the field of research on H. pylori induced GC and aims to provide brief insight into H. pylori pathogenesis, the role of major virulence factors of H. pylori that modulates the host environment and transform the normal gastric epithelium to neoplastic one. This review also emphasizes on the mechanistic understanding of how colonization and various virulence attributes of H. pylori as well as the host innate and adaptive immune responses modulate the diverse signaling pathways that leads to different disease outcomes including GC.  相似文献   
22.
Cyclic AMP (adenosine 3',5'-cyclic monophosphate) concentrations were determined in rat vaginal fluids throughout the estrous cycle. Radioimmunoassay results demonstrated that estrus and early metestrus vaginal fluids had significantly (p less than 0.01) elevated cAMP concentrations compared to proestrus, late metestrus, and early and late diestrus. Ovariectomy reduced RIA-detectable cAMP in vaginal fluid. When cauda sperm were preincubated for 5 min with vaginal fluids from each stage of the estrous cycle, results demonstrated that only estrus- and early metestrus-stage vaginal fluids caused a decrease in [32P]-8N3cAMP (8-azido photoaffinity analogue of cAMP) photolabeling of sperm cAMP-dependent protein kinase regulatory subunits RI and RII. To examine if this reduction in [32P]-8N3cAMP photoincorporation by sperm RI and RII could be due to endogenous cAMP, vaginal fluids were boiled, trypsinized, and/or incubated with EGTA or phosphodiesterase. Only phosphodiesterase-treated vaginal fluids restored sperm regulatory subunit photoincorporation of [32P]-8N3cAMP. It is suggested that cAMP is present in rat vaginal fluids during the estrous cycle in a concentration sufficient to bind the regulatory subunits of rat sperm cAMP-dependent protein kinase.  相似文献   
23.
Meconium staining of the amniotic fluid is a common complication during labour. When facilities like electronic monitoring, foetal blood sampling are not available, it is difficult to decide whether labour should be allowed to continue or caesarean section should be done. Even when caesarean section is done, meconium aspiration syndrome (MAS) can still occur and considerable morbidity and mortality may result in the newborn. Amnioinfusion is being considered as useful in decreasing MAS and its sequelae. Before resorting to amnio infusion, we decided to analyse the perinatal outcome in meconium stained liquor to compare whether early caesarean section offered any advantage. This is a retrospective study of 150 labours complicated by thick meconium stained liquor, during a 12 month period (1992–93).  相似文献   
24.
The present study was designed to investigate the fungi and their toxigenic potentials isolated from the wheat and wheat brans. A total of 67 samples of wheat and 17 samples of wheat bran were collected from Faisalabad district of Pakistan. Forty-five (67.16%) samples of wheat yielded fungi. Frequency distribution based on total samples, Aspergillus was the highest (44.77%) genus followed by Penicillium, Fusarium and Alternaria. Penicillium verucosum (30.64%) was the most frequently isolated species followed by A. niger aggregates, A. flavus, A. parasiticus, P. chrysogenum, A. ochraceous, A. carbonarius and A. fumigatus. Among Aspergilli, A. niger aggregates (46.67%) were most frequently isolated species. Out of 30 Aspergilli isolates from wheat samples, 17 (56.66%) were found toxigenic. AFB1 produced by aflatoxigenic Aspergilli varied from 1.44 to 836.3?ng/g, while ochratoxin A levels varied from 0.037 to 15 045?ng/g. Among Penicillium species, P. verrucosum (63.15%) were found ochratoxigenic and OTA levels were varied from 7.31 to 8400?ng/g. In wheat bran, 10 (58.82%) samples yielded fungi. Based upon total samples, frequency distribution of Aspergillus (35.28%) was the highest followed by Penicillium and Fusarium. Similar pattern was observed in relative density of isolates. A. niger aggregates and P. verrucosum were predominant species (23.07%) isolated from wheat bran. Among Aspergilli, A. niger aggregates (50%) were the most frequently isolated species followed by A. flavus, A. fumigatus and A. ochraceous (16.67%) each. The OTA levels of fungi isolated from wheat bran varies from 0.292 to 2500?ng/g. Isolation of toxigenic A. niger aggregates from wheat indicates that these species should be considered as possible contributors of OTA contamination in wheat and its by-products in Pakistan.  相似文献   
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26.
PurposeSince ancient era leprosy is existing across the world. India, Indonesia and Brazil still harbour major proportion of global cases. Child leprosy and Grade II disability indicate delayed diagnosis and persistence of transmission in community. So, this study was conducted with aim to evaluate the diagnostic efficacy of PCR in comparison to SSS (Slit Skin Smear) microscopy for detection of leprosy in early stages in both cases and carriers (contacts).MethodsA cross sectional observational study was conducted on 100 subjects including 50 clinically diagnosed new cases of leprosy and their 50 contacts. Each group was subjected to SSS (Slit Skin Smear) microscopy and PCR using RLEP gene as target.ResultsThe overall male: female ratio was 2.44. The Slit Skin smear (SSS) microscopy positivity was 34% (n = 17/50) among cases while it was 0% (n = 0/50) among contacts. The overall positivity for PCR was 42% (n = 42/100) being 66% (n = 33/50) in cases and 18% (n = 9/50) in contacts. About 30% (n = 25/83) of all the microscopically negative subjects were found to be positive by PCR.ConclusionsPCR was found to be a better diagnostic tool both among cases and their contacts. It should be used for screening contacts for early diagnosis and treatment and thus preventing transmission in community.Key messageTo diagnose case and contacts of leprosy in early stages even in very low bacterial density using PCR.  相似文献   
27.
The dichloromethane fraction from Areca catechu was found to inhibit monoamine oxidase type A isolated from the rat brain with an IC50 of 665 +/- 65.1 microg/ml. Studies with pharmacological models of depression, i.e., forced swim and tail-suspension tests, indicated that it caused significant reduction in the immobility time similar to that of moclobemide (a selective inhibitor of MAO-A) without causing a significant change in motor performance. Alkaloids such as arecaidine, arecoline, and a few other constituents, reported to be present in Areca catechu were also tested, but none of them were found to inhibit MAO. Present study suggests that the dichloromethane fraction from A. catechu possesses antidepressant property via MAO-A inhibition.  相似文献   
28.
ObjectivesThis audit assesses communication between community optometrists (COs) and hospital eye service (HES) in Scotland and England.MethodsOptometric referrals and replies were extracted from six practices in Scotland and England. If no reply was found, replies/records were copied from HES records. De-identified referrals, replies and records were audited against established standards, evaluating whether referrals were necessary, accurate and directed to the appropriate professional. The referral rate (RR) and referral reply rate (RRR) were calculated.ResultsFrom 905 de-identified referrals, RR ranged from 2.6 to 8.7%. From COs’ perspective, the proportion of referrals for which they received replies ranged from 37 to 84% (Scotland) and 26 to 49% (England). A total of 88–96% of referrals (Scotland) and 63–76% (England) were seen in the HES. Adjusting for cases when it is reasonable to expect replies, RRR becomes 45–92% (Scotland) and 38–62% (England) with RRR significantly greater in Scotland (P = 0.015). Replies were copied to patients in 0–21% of cases. Referrals were to the appropriate service and judged necessary in ≥90% of cases in both jurisdictions. Accuracy of referral ranged from 89 to 97% (Scotland) and 81 to 98% (England). The reply addressed the reason for referral in 94–100% of cases (Scotland) and 93–97% (England) and was meaningful in 95–100% (Scotland) and 94–99% (England).ConclusionsDespite the interdisciplinary joint statement on sharing patient information, this audit highlights variable standard of referrals and deficits in replies to the referring COs, with one exception in Scotland. Replies from HES to COs are important for patient care, benefitting patients and clinicians and minimising unnecessary HES appointments.Subject terms: Health services, Health occupations  相似文献   
29.
Camptomelic dysplasia is a disorder of the newborn characterized by congenital bowing and angulation of long bones together with other skeletal and extraskeletal defects. The affected newborn had dysmorphic features with bowing of the legs and bilateral talipes equinovarus. Radiology showed marked anterior bowing of both tibia with disproportionately short fibula, anterolateral bowing of the femurs and wide pelvic outlet with small iliac wings. She had sex reversal with normal female genitalia and 46, XY karyotype. Camptomelic dysplasia is generally considered to be a lethal skeletal dysplasia and most patients die in the neonatal period due to severe respiratory distress. Survivors may have learning difficulties, developmental delay, conductive hearing loss, myopia and recurrent chest infections. Because of its high associated mortality, prenatal diagnosis of camptomelic dysplasia is mandatory. The birth of a child with skeletal dysplasia is an emotionally difficult experience for parents.  相似文献   
30.
Role of protein kinase B in Alzheimer's neurofibrillary pathology   总被引:11,自引:0,他引:11  
Protein kinase B (PKB) is an important intermediate in the phosphatidylinositol-3 kinase signaling cascade that acts to phosphorylate glycogen synthase kinase-3 (GSK-3) at its serine 9 residue, thereby inactivating it. Activated GSK-3 has been previously shown to be preferentially associated with neurofibrillary tangles (NFTs) in Alzheimer's disease (AD) brain. In the present study, we performed immunohistochemistry with an antibody to the active form of PKB in brains with different stages of neurofibrillary degeneration. We found that the amount of activated PKB (p-Thr308) increased in correlation to the progressive sequence of AT8 immunoreactivity and neurofibrillary changes assessed according to Braak's criteria. By confocal microscopy, activated PKB (p-Thr308) was found to appear in particular in neurons that are known to later develop NFTs in AD. Western blotting showed that activated PKB was increased by more than 50% in the 16,000- g supernatants of AD brains as compared with normal aged and Huntington's disease controls. This increase in PKB levels corresponded with a several-fold increase in the levels of total tau and abnormally hyperphosphorylated tau at the Tau-1 site. These studies suggest the involvement of PKB/GSK-3 signaling in Alzheimer neurofibrillary degeneration.  相似文献   
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