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1.
We have compared levels of albumin and serum amino acids in a group of 87 recent admissions to a nursing home, average age 83 years, with a group of healthy moderately old subjects, average age 69 years. We found that the nursing home group was characterized by decreased levels of albumin, by increased total levels of the measured amino acids, and by increased levels of the nonessential amino acids. In contrast, there were no significant group differences in the essential amino acids. Among the nursing home patients, there was a negative correlation between essential amino acids and disability, consistent with nutritional deficits in the more disabled patients, and a positive correlation between essential amino acids and subjective complaints of pain, suggesting that pain is associated with breakdown or mobilization of endogenous protein stores. Though the nursing home patients had decreased serum levels of tryptophan, there was no association between serum tryptophan or other variables that could be related to the availability of tryptophan for transport into brain, with ratings of either depression or pain. Glutamine levels were significantly increased in the nursing home residents, and among these patients they were positively correlated with measures of cognitive impairment.  相似文献   
2.
Group C rotavirus associated with fatal enteritis in a family outbreak   总被引:21,自引:0,他引:21  
A family outbreak of gastroenteritis involving three adults and three children is described in which diarrhoea and vomiting were the main clinical features. One infant died in whom no pathogens could be detected in either small or large intestinal postmortem samples. Stool samples from two symptomatic siblings contained rotaviruses as demonstrated by electron microscopy. Both of these faecal samples were negative when assayed in a group A specific rotavirus enzyme-linked immunosorbent assay (ELISA) and subsequent genomic analysis of these rotaviruses was suggestive of group C rotavirus. Serological evidence showed that these atypical rotaviruses were members of serogroup C. Other atypical rotaviruses in faecal samples from sporadic cases in symptomatic children were detected over a similar time period and location. These had electrophoretic RNA profiles similar to those in the family outbreak. Furthermore, seroepidemiological studies detected group C rotavirus antibody in blood donors resident in the location of the family outbreak.  相似文献   
3.
The reovirus-like particles present in the feces of young pigs and foals with acute enteritis and the virus causing epizootic diarrhea of infant mice were found to be indistinguishable morphologically from each other, from the South African SA. 11 and "O" viruses, and from the rotaviruses of children and calves. The inner capsid layer of each of these viruses reacted seriologically with sera of children, calves, mice, piglets, and foals convalescent from infection with their respective rotaviruses. These sera reacted by immunofluorescence with human, bovine, porcine, and murine rotaviruses, SA.11, and "O" viruses in tissue cultures and with human bovine, procine, nad murine viral antigens by complement fixation and gel diffusion. However, the antisera differed in their ability to react serologically with the outer capsid layer of the viruses investigated and in their ability to neutralize tissue culture-adapted calf virus. These two tests may demonstrate strain or host specificity among rotaviruses. Since the porcine, murine, and equine viruses are closely related serologically to and are morphologically identical to the human and bovine viruses, they should be included in the group of viruses for which the term "rotavirus" has been suggested. All known members of this proposed group of viruses share a common antigen, probably situated within the inner capsid layer; thus, any one of the viruses may be used for the preparation of antigen or antibody for diagnostic tests, and this will aid in the diagnosis of virus infection in those species from which a rotavirus has not been cultured.  相似文献   
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A desirable test to diagnose infections with Mycobacterium avium subsp. paratuberculosis facilitates identification of infected cattle prior to the state of M. avium subsp. paratuberculosis shedding. This study aimed at adjusting a flow cytometry (FC)-based assay, using intact M. avium subsp. paratuberculosis bacteria as the antigen, for diagnosis of M. avium subsp. paratuberculosis infections in calves. Serum samples were collected from experimentally infected (n = 12) and naturally exposed (n = 32) calves. Samples from five calves from positive dams were analyzed to determine the dynamics of maternal antibodies. Samples from adult cattle with defined infection status served as the standard (18 M. avium subsp. paratuberculosis shedders, 22 M. avium subsp. paratuberculosis free). After preadsorption with Mycobacterium phlei, sera were incubated with M. avium subsp. paratuberculosis and M. avium subsp. avium bacterial suspensions, respectively, followed by the separate detection of bovine IgG, IgG1, IgG2, and IgM attached to the bacterial surface. M. avium subsp. paratuberculosis-specific sample/positive (S/P) ratios were compared to enzyme-linked immunosorbent assay (ELISA) S/P ratios. In adult cattle, the FC assay for IgG1 had a sensitivity of 78% at a specificity of 100%. Maternally acquired antibodies could be detected in calves up to 121 days of life. While all but two sera taken at day 100 ± 10 postnatum from naturally exposed calves tested negative, elevated S/P ratios (IgG and IgG1) became detectable from 44 and 46 weeks postinoculation onwards in two calves infected experimentally. Even with the optimized FC assay, M. avium subsp. paratuberculosis-specific antibodies can only occasionally be detected in infected calves less than 12 months of age. The failure to detect such antibodies apparently reflects the distinct immunobiology of M. avium subsp. paratuberculosis infections rather than methodological constraints.  相似文献   
8.
Two surgical approaches were used for nasal and ethmoid cancers involving the anterior skull base. A craniofacial operation with the assistance of a neurosurgeon was employed when the cribriform plate was infiltrated. A frontofacial operation through the frontal sinus was preferred when the cribriform plate was radiologically intact. Thirty patients underwent radical surgery with a minimum three-year follow-up. Thirteen of 16 patients with adenocarcinoma survived. Since 1980, nine patients have had their surgical defects repaired with a revascularized tensor fascia lata muscle and skin flap. The flap is tailored to support the cranial contents, provide muscle bulk for the orbitomaxillectomy cavity, and provide skin for the face, nasal, and palatal surfaces. There were two free flap failures.  相似文献   
9.
Electrodermal activity of 11 children with conduct disorder (CD) and 11 normal children were compared during periods of rest, moderate tone and loud bell stimulation. The CD group was best differentiated from controls by lower reactivity to the first bell, while on tonic measures they showed normal values. The electrodermal profile of the CD children thus resembled that of adult sociopaths on phasic measures only. The possibility of using electrodermal measures for predicting outcome and for differential diagnosis is raised.  相似文献   
10.
Teaching medical students to integrate patient-centered skills into the medical interview is challenging. Longitudinal training requires significant curricular and faculty time. Unsupervised students risk harm if they uncover and inappropriately manage psychosocial issues in actual patients. They fear saying the wrong thing in emotionally charged situations. Two half-day workshops for pre-clinical students integrate patient- and physician-centered interviewing. The first occurs early in the first year. The second, late in the second year, presents interview challenges (e.g., breaking bad news). Ten professional actors portray standardized patients (SPs). Groups of 10 to 15 students interview an SP, each eliciting a part of the patient's story. Qualitative evaluation revealed that, for many students, SPs afford the opportunity to experiment without harming real patients. Students view the workshops as effective (mean score for first-year students, 6.6 [standard deviation (SD), 1.0], second-year students, 7.1 [SD, 0.7] on a Likert-type scale: 1 = not at all effective to 8 = very effective).  相似文献   
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