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121.
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Alcohol consumption during pregnancy can lead to a variety of cognitive and other birth defects, collectively termed fetal alcohol spectrum disorders (FASD), and including the Fetal Alcohol Syndrome (FAS). This study examined the impact of gestational alcohol exposure on the morphology of the cingulate gyrus, given this region's role in cognitive control, attention, and emotional regulation, all of which are affected in children with FASD. Thirty-one youth (ages 8–16) with histories of heavy prenatal alcohol exposure (n = 21) and demographically matched comparison subjects (n = 10) underwent structural magnetic resonance imaging. The cingulate gyrus was manually delineated, and parcellated volumes of grey and white matter were compared across groups. Alcohol-exposed individuals had significantly smaller raw cingulate grey matter, white matter, and tissue volumes compared with controls. After adjustment for respective cranial tissue constituents, only white matter volumes remained significantly reduced, and this held regardless of whether or not the child qualified for a diagnosis of FAS. A correlation between posterior cingulate grey matter volume and the WISC-III Freedom from Distractibility Index was also observed in alcohol-exposed children. These data suggest that cingulate white matter is compromised beyond global white matter hypoplasia in alcohol-exposed individuals, regardless of FAS diagnosis. The observed volumetric reductions in the cingulate gyrus may contribute to the disruptive and emotionally dysregulated behavioral profile commonly observed in this population.  相似文献   
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Cytogenetic and histologic correlations in malignant lymphoma   总被引:9,自引:0,他引:9  
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change.  相似文献   
125.
OBJECTIVES: Studies of the relative frequency of transient lower esophageal sphincter relaxations (TLESRs) in patients with gastroesophageal reflux disease and asymptomatic controls have revealed conflicting data. We have therefore studied the frequency of TLESRs and the frequency and mechanisms of acid reflux episodes in patients with gastroesophageal reflux disease and age- and sex-matched asymptomatic controls using standardized criteria. METHODS: Ten patients with symptomatic gastroesophageal reflux disease (four male, aged 50 [30-59] yr) and 10 asymptomatic matched volunteers (four male, aged 50 [32-59] yr) were studied. Esophageal, lower esophageal sphincter, and gastric manometric and esophageal pH readings were recorded for 1 h before and 1 h after a 200-kcal, 150 ml long-chain triglyceride meal. RESULTS: TLESR frequency increased after the meal in both volunteers (median 0 [range = 0-3] to 3 [0-8] per hour,p < 0.01) and patients (1 [0-6] to 2.5 [0-9] per hour, p = 0.08). There was no significant difference in the frequency of TLESRs between volunteers and patients. TLESRs were more likely to be associated with acid reflux in patients (65% vs 37%, p = 0.03), whereas volunteers were more likely to reflux gas or liquid without acid (30% vs 3.0%, p = 0.01). CONCLUSIONS: TLESRs are no more frequent in patients with gastroesophageal reflux disease than age- and sex-matched asymptomatic volunteers. However, when TLESRs occur in patients, they are twice as likely to be associated with acid reflux.  相似文献   
126.
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Genetic influences in gastro-oesophageal reflux disease: a twin study   总被引:11,自引:0,他引:11       下载免费PDF全文
Mohammed I  Cherkas LF  Riley SA  Spector TD  Trudgill NJ 《Gut》2003,52(8):1085-1089
BACKGROUND: A number of families have been described which include multiple members with symptomatic, endoscopic, or complicated gastro-oesophageal reflux disease (GORD). First degree relatives of patients with GORD are more likely to suffer with GORD symptoms. These observations raise the possibility of a genetic contribution to the aetiology of GORD. AIMS: To determine the relative contribution of genetic factors to GORD by evaluating GORD symptoms in monozygotic (MZ) and dizygotic (DZ) twins. METHODS: A total of 4480 unselected twin pairs, identified from a national volunteer twin register, were asked to complete a validated symptom questionnaire. GORD was defined as symptoms of heartburn or acid regurgitation at least weekly during the past year. RESULTS: Replies were obtained from 5032 subjects (56% response rate). A total of 1960 twin pairs were evaluable: 928 MZ pairs (86 male pairs, mean (SD) age 52 (13) (range 19-81) years) and 1032 DZ pairs (71 male pairs, mean age 52 (13) (20-82) years). The prevalence of GORD among both groups of twins was 18%. Casewise concordance rates were significantly higher for MZ than DZ twins (42% v 26%; p<0.001). Multifactorial liability threshold modelling suggests that additive genetic effects combined with unique environmental factors provide the best model for GORD. Heritability estimates suggest that 43% (95% confidence interval 32-55%) of the variance in liability to GORD is due to additive genetic factors. CONCLUSIONS: There is a substantial genetic contribution to the aetiology of GORD.  相似文献   
128.
BACKGROUND: Alcohol exposure during development can produce severe and long-lasting central nervous system damage and consequent behavioral alterations. Recent evidence suggests that NMDA receptor-mediated excitotoxicity during periods of withdrawal may contribute to this damage. We have demonstrated that blocking the NMDA receptor with MK-801 during alcohol withdrawal can attenuate ethanol's adverse effects on behavioral development in the rat. This study examined the dose dependency of MK-801's ability to mitigate ethanol's teratogenic effects. METHODS: Neonatal rat pups were exposed to 6.0 g/kg of ethanol in a binge-like manner on postnatal day (PD) 6, a period of brain development equivalent to a portion of the human third trimester. Alcohol administration was accomplished with an artificial rearing procedure. Twenty-one hours after ethanol treatment, pups were injected intraperitoneally with one of four doses of MK-801 (0.05, 0.1, 0.5, or 1.0 mg/kg) or saline vehicle. An artificially reared control and a normally reared control group were included. On PD 18-19, activity level was monitored, and on PD 40-42, serial spatial discrimination reversal learning was assessed. RESULTS: Alcohol exposure on PD 6 produced significant increases in activity level and deficits in reversal learning. These alcohol-induced behavioral alterations were significantly attenuated in subjects treated with one of the three lower doses (0.05-0.5 mg/kg) of MK-801 during withdrawal. The performance of ethanol-exposed subjects treated with the high dose of MK-801 (1.0 mg/kg) did not differ from that of the Ethanol Only group. CONCLUSIONS: These data suggest that alterations in NMDA receptor activation during alcohol withdrawal contribute to the neuropathology and consequent behavioral alterations associated with developmental alcohol exposure. These data have important implications for pregnant women and newborns undergoing ethanol withdrawal.  相似文献   
129.
Naccache  PH; Jean  N; Liao  NW; Bator  JM; McColl  SR; Kubes  P 《Blood》1994,84(2):616-624
The control of the adhesive properties of human neutrophils is an essential element of their defense function. One level at which this control is exerted involves the upregulation of the surface expression of beta 2-integrins. In this study, we have examined the potential involvement of tyrosine phosphorylation in the latter process. Two inhibitors of tyrosine kinases with differing modes of action, erbstatin and herbimycin A, were found to inhibit the expression of CD11b and CD18 stimulated by chemotactic factors (fMet-Leu-Phe or leukotriene B4) or growth factors (tumor necrosis factor alpha). This inhibition was not shared by an inactive analog of erbstatin or by the protein kinase C inhibitor Ro 31-8330. Erbstatin also inhibited the unveiling of activation-specific neoepitopes detected by antibody CBRM1/5. Pretreatment of neutrophils (but not of endothelial cells) with erbstatin inhibited the stimulation of neutrophils' adherence to endothelial cells induced by fMet-Leu-Phe. Augmentation of tyrosine phosphorylation by inhibiting tyrosine phosphatases using hydroperoxyvanadate led to an increased surface expression of CD11b and CD18 and enhanced the adhesion of neutrophils to endothelial cells. Finally, the leumedin NPC 15669, which had previously been shown to inhibit stimulated CD11b expression and neutrophil adherence to endothelial cells and to exhibit anti-inflammatory properties in various in vivo models of inflammation, inhibited the stimulation of tyrosine, phosphorylation induced by fMet-Leu-Phe. Taken together, these data establish a strong correlation between tyrosine phosphorylation and integrin upregulation in stimulated human neutrophils.  相似文献   
130.
Hematopoietic chimerism was analyzed in serial bone marrow samples taken from 28 children following T-cell depleted unrelated donor bone marrow transplants (UD BMT) for acute lymphoblastic leukemia (ALL). Chimeric status was determined by polymerase chain reaction (PCR) of simple tandem repeat (STR) sequences (maximal sensitivity, 0.1%). At least two serial samples were examined in 23 patients. Of these, two had evidence of complete donor engraftment at all times and eight showed stable low level mixed chimerism (MC) (<1% recipient hematopoiesis). All 10 of these patients remain in remission with a minimum follow-up of 24 months. By contrast, 13 patients demonstrated a progressive return of recipient hematopoiesis. Five of these relapsed (4 to 9 months post BMT), one died of cytomegalovirus pneumonitis and seven remain in remission with a minimum follow-up of 24 months. Five children were excluded from serial analysis as two serial samples were not collected before either relapse (3) or graft rejection (2). We conclude that as with sibling transplants, ex vivo T depleted UD BMT in children with ALL is associated with a high incidence of MC. Stable donor engraftment and low level MC always correlated with continued remission. However, detection of a progressive return of recipient cells did not universally correlate with relapse, but highlighted those patients at greatest risk. Serial chimerism analysis by PCR of STRs provides a rapid and simple screening technique for the detection of relapse and the identification of patients with progressive MC who might benefit from detailed molecular analysis for minimal residual disease following matched volunteer UD BMT for childhood ALL.  相似文献   
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