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1.
A copper-based framework Cu2(OBA)2(BPY) was synthesized and used as a recyclable heterogeneous catalyst for the synthesis of β-sulfonylvinylamines from sodium sulfinates and oxime acetates via direct C–S coupling reaction. The transformation was remarkably affected by the solvent, and chlorobenzene emerged as the best option. This Cu-MOF displayed higher activity than numerous conventional homogeneous and MOF-based catalysts. The catalyst was reutilized many times in the synthesis of β-sulfonylvinylamines without considerably deteriorating in catalytic efficiency. These β-sulfonylvinylamines were readily converted to the corresponding β-ketosulfones via a hydrolysis step with aqueous HCl solution. To the best of our knowledge, this direct C–S coupling reaction to achieve β-sulfonylvinylamines was not previously conducted with a heterogeneous catalyst.

Cu2(OBA)2(BPY) was used as catalyst for the synthesis of β-sulfonylvinylamines from sodium sulfinates and oxime acetates. These β-sulfonylvinylamines were readily converted to corresponding β-ketosulfones via a hydrolysis step.  相似文献   
2.
BACKGROUND: Tuberculous meningitis (TBM) caused by Mycobacterium tuberculosis resistant to 1 or more antituberculosis drugs is an increasingly common clinical problem, although the impact on outcome is uncertain. METHODS: We performed a prospective study of 180 Vietnamese adults admitted consecutively for TBM. M. tuberculosis was cultured from the cerebrospinal fluid (CSF) of all patients and was tested for susceptibility to first-line antituberculosis drugs. Presenting clinical features, time to CSF bacterial clearance, clinical response to treatment, and 9-month morbidity and mortality were compared between adults infected with susceptible and those infected with drug-resistant organisms. RESULTS: Of 180 isolates, 72 (40.0%) were resistant to at least 1 antituberculosis drug, and 10 (5.6%) were resistant to at least isoniazid and rifampicin. Isoniazid and/or streptomycin resistance was associated with slower CSF bacterial clearance but not with any differences in clinical response or outcome. Combined isoniazid and rifampicin resistance was strongly predictive of death (relative risk of death, 11.63 [95% confidence interval, 5.21-26.32]) and was independently associated with human immunodeficiency virus infection. CONCLUSIONS: Isoniazid and/or streptomycin resistance probably has no detrimental effect on the outcome of TBM when patients are treated with first-line antituberculosis drugs, but combined isoniazid and rifampicin resistance is strongly predictive of death.  相似文献   
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OBJECTIVE: To examine the influence of life course socioeconomic disadvantages (SED) on cognitive function in later life. METHOD: Data originate from a survey of people 60 and older living in seven Latin American and Caribbean cities. Cognitive function was measured with a modified Mini-Mental State Examination and the Pfeffer Scale of Functional Capacity. Homogeneity tests were used to pool data. Associations between cognitive function and SED were evaluated, fitting logistic regressions. RESULTS: Cognitive impairment (CI) prevalence ranged from 0.3% to 6.5% in men and 1.2% to 10.1% in women. Childhood rural living, poor childhood health, illiteracy, housewife or farmer occupation, and insufficient income were associated with CI in all seven cities. The odds of CI increase with cumulative exposure to disadvantages along life course. CONCLUSIONS: Life course SED is related to cognitive function later in life. Difficulty in properly distinguishing cognitive function from test performance remains an issue.  相似文献   
5.
Interval breast cancers (those diagnosed between recommended mammography screens) generally have poorer outcomes and are more common among women with dense breasts. We aimed to develop a risk model for interval breast cancer. We conducted a nested case–control study within the Melbourne Collaborative Cohort Study involving 168 interval breast cancer patients and 498 matched control subjects. We measured breast density using the CUMULUS software. We recorded first-degree family history by questionnaire, measured body mass index (BMI) and calculated age-adjusted breast tissue aging, a novel measure of exposure to estrogen and progesterone based on the Pike model. We fitted conditional logistic regression to estimate odds ratio (OR) or odds ratio per adjusted standard deviation (OPERA) and calculated the area under the receiver operating characteristic curve (AUC). The stronger risk associations were for unadjusted percent breast density (OPERA = 1.99; AUC = 0.66), more so after adjusting for age and BMI (OPERA = 2.26; AUC = 0.70), and for family history (OR = 2.70; AUC = 0.56). When the latter two factors and their multiplicative interactions with age-adjusted breast tissue aging (p = 0.01 and 0.02, respectively) were fitted, the AUC was 0.73 (95% CI 0.69–0.77), equivalent to a ninefold interquartile risk ratio. In summary, compared with using dense breasts alone, risk discrimination for interval breast cancers could be doubled by instead using breast density, BMI, family history and hormonal exposure. This would also give women with dense breasts, and their physicians, more information about the major consequence of having dense breasts—an increased risk of developing an interval breast cancer.  相似文献   
6.
Tbx1 is the candidate gene of DiGeorge syndrome and is required in humans and mice for the development of the cardiac outflow tract (OFT) and aortic arch arteries. Loss of function mutants present with reduced cell proliferation and premature differentiation of cardiac progenitor cells of the second heart field (SHF). Tbx1 regulates Fgf8 expression hence the hypothesis that the proliferation impairment may contribute to the heart phenotype of mutants. Here we show that forced Fgf8 expression modifies and partially rescues the OFT septation defects of Tbx1 mutants but only if there is some residual expression of Tbx1. This genetic experiment suggests that Tbx1, directly or indirectly, affects tissue response to Fgf8. Indeed, Tbx1−/− mouse embryonic fibroblasts were unable to respond to Fgf8 added to the culture media and showed defective response of Erk1/2 and Rsk1. Our data suggest a coordinated pathway modulating Fgf8 ligand expression and tissue response to it in the SHF.  相似文献   
7.
Theobjectiveofthestudywastoprovetherelaxationeffectoftraditionalmedicinebyob jectivebiologicalindexesbymodernscientificmethods.  Fiftyhealthyelderlypeople,agedfrom6 0to 75,wereselectedtohavetraditionalme dicinalrelaxingpractice,thatis,torelaxtheirbodyin 3…  相似文献   
8.
The herbivorous convict tang or surgeon fish, Acanthurus triostegus, collected at different locations in the Hawaiian islands, was analyzed for toxicity using a mouse bioassay and a stick enzyme immunoassay (S-EIA) developed to detect ciguatoxin and closely related polyethers. Results of the S-EIA test indicated that about 94% of the samples gave negative readings, while 6% of the fish were positive and thus considered toxic. Fish samples from each location were pooled and the flesh and viscera were successively extracted with hexane, methanol, and water and tested in a mouse bioassay. About one-third of the methanol soluble fractions killed mice within 20 min, 70% killed within 4 hr, and 85% killed within 48 hr. About 40% of the hexane-soluble fractions killed mice within 24 hr and 55% killed within 48 hr. The water-soluble extracts of the flesh and viscera of fish taken from three locations showed relatively high toxicity. Common symptoms for all fractions included convulsions and jumping (especially just prior to death), respiratory distress, hind leg to complete paralysis, loss of body tone, and tremors. Analysis of the data suggests that in the flesh and viscera of A. triostegus there are at least three different nervous system-type toxins, most of which did not appear to react to the S-EIA test.  相似文献   
9.
Journal of Assisted Reproduction and Genetics - Oocyte in vitro maturation (IVM) is an assisted reproductive technology designed to obtain mature oocytes following culture of immature...  相似文献   
10.
A novel in vivo binding test was developed in order to evaluate the degree of occupancy of enkephalinase (EC 3.4.24.11), a membrane-bound metallopeptidase, in cerebral and peripheral tissues of mice treated with enkephalinase inhibitors. The probe selected for this purpose was the prodrug [3H]acetorphan, a lipophilic diesterified derivative of the potent enkephalinase inhibitor thiorphan readily releasing the latter by tissue hydrolysis. In order to validate the in vivo binding assay, [3H]thiorphan binding to membranes was first studied in vitro. [3H]Thiorphan binding to cerebral and peripheral tissues (lung and kidney) was saturable over a low nonspecific binding, occurring with a KD of 0.6 nM consistent with the Ki of the compound as enkephalinase inhibitor. [3H]Thiorphan binding varied largely among various tissues and was highly correlated with the catalytic activity of enkephalinase, thus indicating a selective labeling of the peptidase. After the i.v. administration of [3H]acetorphan a large fraction of the radioactivity remained bound to membranes isolated by a rapid filtration assay. Bound radioactivity mainly corresponded to [3H] thiorphan as identified by high-performance liquid chromatography analysis of kidney membranes, whereas unchanged [3H]acetorphan was not detectable. In vivo binding generated by [3H]acetorphan was saturable, with maximum binding sites values which were in rather good agreement with corresponding maximum binding sites values of [3H]thiorphan binding in vitro, particularly in brain. Specific in vivo binding was calculated as the difference between total and a generally low, nonspecific binding evaluated in mice receiving a large dose of nonlabeled acetorphan. Specific in vivo binding varied largely among tissues and generally reflected the abundance of enkephalinase molecules in the latter.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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