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31.
Gonadal and olfactory features of Kallmann's syndrome, usually considered to be inherited as an X-linked recessive trait, were found in a father and son who both had cryptorchidism, hypogonadism, and hyposmia. The father's fertility had been induced with chorionic gonadotropin, leading to the birth of three children. Olfactory and gonadal functions were normal in the mother and two siblings. The father had low basal plasma testosterone and subnormal follicle stimulating hormone (FSH) response to luteinizing hormone-releasing hormone (LH-RH). The affected son and his healthy brother were prepubertal. Their basal plasma total and free testosterone, serum FSH and luteinizing hormone (LH), and response to LH-RH were similar. The clinical presentation and formal olfactory function studies were considered most helpful for the suggestive diagnosis of Kallmann's syndrome in children. The occurrence of this syndrome in this family is consistent with autosomal dominant inheritance.  相似文献   
32.
We investigated the relationship between the extent of coronary artery disease (CAD) and the likelihood of cigarette smoking cessation in a population of 84 smokers between 21 and 75 years of age undergoing elective or urgent coronary angiography at the University of Massachusetts Medical Center. The smokers were enrolled in a pilot study investigating the relationship of hospitalization and coronary arteriography for coronary artery disease to subsequent smoking cessation and were scored at baseline as having none, one-, two-, or three-vessel disease. Smoking status at a mean follow-up time of 11 months was obtained by telephone interview, at which point 50% reported not smoking. Logistic regression showed a significant relationship between smoking cessation and two factors: the anatomic extent of CAD and the experience of having had coronary artery bypass surgery or percutaneous transluminal coronary angioplasty following the initial catheterization. We discuss the relative roles of patient knowledge and motivation and physician intervention, and their implications for smoking cessation interventions.  相似文献   
33.
Noncardiogenic pulmonary edema is a recognized but uncommon manifestation of type 2 decompression sickness. It typically occurs within 6 hours of a dive. Because the adult respiratory distress syndrome in this setting is believed to be due to microbubbles in the pulmonary vasculature, recompression in a hyperbaric chamber has been recommended as a form of therapy. A patient developed noncardiogenic pulmonary edema following a seawater dive to 75 feet. There was complete radiologic and clinical resolution within 5 hours of hyperbaric therapy.  相似文献   
34.
To define the role of noradrenergic regulation of growth hormone (GH) secretion in a primate species, spontaneous and GH-releasing hormone (GHRH) stimulated GH secretion was studied in 6 chronically catheterized adult male cynomolgus monkeys before and after inhibition of norepinephrine synthesis. Blood samples were obtained at 15-min intervals during an 8-hour period to characterize the pattern of GH secretion, and the GH response to GHRH, 10 micrograms/kg i.v., was determined. These measurements were repeated 2 weeks later, 2 h after the intravenous administration of 12.5 mg/kg of the dopamine-beta-hydroxylase inhibitor diethyldithiocarbamate (DDTC), which has been shown to be an effective norepinephrine synthesis inhibitor in the rat. Spontaneous and stimulated GH secretory patterns before and after DDTC administration were compared. Both the frequency and the amplitude of spontaneous GH pulses were markedly reduced by DDTC [3.8 +/- 0.4 before vs. 1.8 +/- 0.4 peaks/8 h after DDTC (p less than 0.005) and 5.5 +/- 0.7 vs. 2.0 +/- 0.6 ng/ml (p less than 0.01)]. Areas under the curve were also reduced by DDTC treatment [10.8 +/- 1.0 vs. 5.7 +/- 1.1 ng.h/ml (p less than 0.01)], and DDTC administration diminished the peak GH responses to GHRH [12 +/- 6 vs. 4 +/- 2 ng/ml (p less than 0.05)]. These results are consistent with the belief that DDTC is a potent inhibitor of spontaneous and GHRH-induced GH secretion. The action of DDTC could be mediated by a reduction in GHRH due to reduced norepinephrine synthesis, by an increase in somatostatin release through a dopaminergic stimulus, or by a direct dopaminergic effect on somatotrophs.  相似文献   
35.
The purpose of this study was to determine whether schizophrenics with positive, mixed, and negative syndromes are distinguished in terms of visual stimulus registration thresholds and efficiency of information processing. Forty-five schizophrenic inpatients were classified accordingly into groups of 15 each and compared with one another and with 15 normal control subjects on a visual backward masking task. Repeated-measures analysis of variance revealed that all three schizophrenic groups were less efficient information processors than were normal subjects. Relative to the positive group, the negative group displayed significantly longer registration thresholds, fewer correct target stimulus detections, and longer time intervals to achieve their first significant improvement in performance and to first exceed chance response levels. The three syndrome groups were not significantly different in their rates of improvement over trials. Secondary correlational analyses showed that the information-processing measures were unrelated to a variety of demographic, psychiatric, and cognitive developmental variables, although shorter recognition thresholds and shorter unmasking interval scores were associated with faster psychomotor rates. Complex interrelationships were uncovered between the information-processing measures, positive and negative symptomatology, and general psychopathology. The results were interpreted as supporting the validity of the positive-negative distinction for explaining some of the heterogeneity in schizophrenia.  相似文献   
36.
Neurological signs and the positive-negative dimension in schizophrenia   总被引:1,自引:0,他引:1  
Schizophrenic patients have been observed to manifest a variety of abnormal neurological signs, but the nature of their association with differing clinical presentations is less well established. To address this issue, we administered a newly compiled neurological inventory to 28 well-characterized chronic schizophrenic inpatients and separately assessed them on the Positive and Negative Syndrome Scale and on control variables that included measures of global pathology, chronicity of illness, neuropsychological and intellectual integrity, and extrapyramidal dysfunction. We found, first, that our neurological battery provided statistically independent measures of apraxia, fine motor function, and prefrontal, parietal, and nonlocalizing signs. A significant association emerged between negative symptomatology and neurological signs of prefrontal impairment (p less than 0.01), which could not be accounted for by any of the control variables. Positive symptoms were associated with an absence of parietal and nonlocalizing signs; however, these correlations were mediated by higher neuroleptic doses in these patients. There was no association between any neurological sign and age, extrapyramidal symptoms, general neuropsychological integrity, education, IQ, or severity or chronicity of illness. We concluded that the negative syndrome in schizophrenia represents a distinct dimension of psychopathology that is related specifically to prefrontal deficit.  相似文献   
37.
The restitution of normal fibergenesis that occurs in stationary radiation cataracts provides a unique opportunity to study the cytopathomechanism of radiocataractogenesis. Previous attempts at investigating this phenomenon have been limited by the lack of an appropriate animal model. This report describes the induction of stationary radiation cataracts in postmetamorphic bullfrogs following ocular irradiation with a 10 Gy (1 Gy = 100 rads) dose of X-rays. The eyes of non-irradiated animals and animals irradiated with 25 Gy (an established dose known to induce progressive cataracts in frogs) served as controls. Animals were followed biomicroscopically and histopathologically over 79 weeks. As previously described, the cataracts developed in a dose-dependent manner. The 25 Gy irradiated lenses rapidly progressed to complete opacification (4+) by 26 weeks, while lenses exposed to 10 Gy advanced to the 2.5+ stage by 35 weeks and progressed no further. In the lower dose lenses, transparent cortex began to appear anteriorly and posteriorly between the capsule and opaque fibers at 45 weeks. As the clear fibers accumulated, the disrupted region came to occupy increasingly deeper cortex. Histologically, opacities in both groups were preceded by disorganization of the bow cytoarchitecture, meridional row disorganization, and the appearance in the lens epithelium of nuclear polymorphism, fragmented nuclei, micronuclei, clusters of nuclei, and abnormal mitotic figures. In the lenses exposed to the 25 Gy dose, this damage continued to worsen, so that the 4+ stage was characterized by extensive epithelial cell death, absence of the lens bow, degenerated fiber masses, and liquefied substrata. In contrast, prior to the appearance of transparent cortex in the 10 Gy group, the lens epithelial aberrations, are of the bow, and meridional row disorganization were all observed to improve. Further, by 69 weeks, the lens epithelium appeared as a largely homogeneous population, and the meridional rows and the are of the bow had become reestablished. The details of these observations and their possible relationship to the cytopathomechanism of radiation cataract formation are discussed.  相似文献   
38.
39.
The comparative in vitro activities of 11 iodonium salt compounds, 0.12% chlorhexidine, and four antimicrobial agents against 322 anaerobic and fastidious potential dental and periodontal bacterial pathogens were studied. Iodonium salts 3, 4, 5, 9, and 10 had in vitro activities comparable to that of chlorhexidine against most isolates. These compounds may be suitable for incorporation into an oral mouthwash.  相似文献   
40.
BMS-284756, a new des-fluoro(6) quinolone, was very active against 240 aerobic and 180 anaerobic isolates from bite victims. It inhibited 403 of 420 (96%) isolates, including those of Moraxella spp., CDC group EF-4, and Eikenella corrodens at < or = 2 microg/ml and those of all Pasteurella spp. and Bergeyella zoohelcum at < or = 0.015 microg/ml. Fusobacterium russii and 6 of 11 Fusobacterium nucleatum isolates of animal bite origin were resistant, but isolates of human bite origin were susceptible, which suggests that they were of a different subspecies.  相似文献   
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