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141.
X-linked hypophosphatemia in adults: prevalence of skeletal radiographic and scintigraphic features 总被引:3,自引:0,他引:3
The radiologic studies of 38 essentially untreated adults with X-linked hypophosphatemia (XLH) were reviewed to determine the prevalence of radiologic features, to compare the findings in men and in women, and to elucidate the natural history of the disease by comparing the findings in young, intermediate-age, and older patients. Bone-reinforcement lines were common, but no characteristic mineral mass alteration was established. Looser zones were more prevalent in older subjects. Osteoarthritis was common, occurring in the ankles, knees, feet, sacroiliac joints, and wrists. Enthesopathy was infrequent in the younger group but was present in every member of the intermediate and older groups and was often accompanied by extra ossicles. Curvatures of the lower-extremity long bones were common in all age groups. Three new skeletal alterations in XLH were found to be common: flaring of the iliac wings, trapezoidal distal femoral condyles, and alterations in talar morphology, including shortening of the talar neck and flattening of the talar dome. Technetium-99m methylene diphosphonate scintigrams of 17 subjects were often abnormal, depicting bowing deformity and focal tracer accumulation in diaphyseal cortices and in periarticular and extraarticular regions. The mean metabolic index was moderately elevated (4.0). Both radiographic and scintigraphic findings were more severe in men, consistent with hemizygosity. The natural history of untreated XLH in both sexes is characterized by the development of a variety of age-related skeletal abnormalities during adulthood. 相似文献
142.
143.
Women worried about their familial breast cancer risk--a study on genetic advice in general practice
de Bock GH; Perk DC; Oosterwijk JC; Hageman GC; Kievit J; Springer MP 《Family practice》1997,14(1):40-43
AIMS: To ascertain whether women who consulted their GP because they
perceived themselves as at increased risk of familial breast cancer were
indeed at increased risk, and to evaluate potential strategies for
assessing genetic risk of breast cancer in general practice. METHODS:
Sixty-seven out of 81 women who had consulted their GP for advice about
their possible increased risk of developing breast cancer due to breast
cancer in the family were interviewed. Familial breast cancer risk was
assessed by a clinical geneticist. This assessment was compared with two
recent guidelines for referral for genetic counselling. RESULTS: More than
half (52%; n = 35) the women had a relative risk of two and over for
developing breast cancer, while another half of these 35 (25%; n = 17) had
a relative risk of three and over. All the women (n = 17) with a relative
risk of three and over were identified by means of the two current
guidelines for referral for genetic counselling, while more than half of
the women (61%; n = 11) with a relative risk between two and three were
identified. CONCLUSIONS: More than half the women concerned about their
familial risk of breast cancer are indeed at increased risk of breast
cancer. Current guidelines correctly identify women at high risk. However,
doubts about the health gain and feasibility of referral warrant caution,
and need further investigation.
相似文献
144.
Stimulation of serum cortisol and prolactin secretion in humans by MK-212, a centrally active serotonin agonist 总被引:1,自引:0,他引:1
The effects of MK-212 [6-chloro-2-(1-piperazinyl)-pyrazine] (10, 20, and 40 mg, orally), a centrally acting serotonin (5-HT) receptor agonist and placebo, on serum cortisol, prolactin, and growth hormone levels were studied in eight healthy men over 3-hr. MK-212 produced a dose-related increase in serum cortisol levels, with the 20- and 40-mg doses producing significant elevations. Serum prolactin levels were significantly elevated only by the 40-mg dose. Serum GH levels were not significantly modified by any dose of MK-212. The cortisol and prolactin responses to the 40-mg dose of MK-212 were positively correlated (rho = + 0.85, p less than 0.02). MK-212 was generally well tolerated by the subjects. Headache and nausea were observed at the higher doses, but did not appear to be related to the increase in serum cortisol and prolactin levels. MK-212 may stimulate the secretion of cortisol and prolactin in humans via a serotonin (5-HT2) receptor mechanism and may be a valuable tool with which to study 5-HT receptor sensitivity in humans. 相似文献
145.
146.
A M Lowy D K Ingram D S Olton S B Waller M A Reynolds E D London 《Behavioral neuroscience》1985,99(4):638-651
The performances of young (8-9 months) and aged (22-24 months) male ACI rats were compared in a T-maze requiring two discriminations, each of which placed different demands on memory processing. A spatial discrimination in the stem of the T-maze required long-term reference memory; a discrete-trial, alternation discrimination in the arms of the T-maze required working memory. Following acquisition training in one maze, rats were also trained in a second maze at a different location in the room. The correct response in the stem of this maze was opposite to that in the first maze. In two experiments with slightly different pretraining procedures, similar results demonstrated that aged rats made more errors in all phases of maze training than did their young counterparts. The results suggest that all components of memory processing were affected equivalently because the age-related impairment was not selectively greater in any component of the task. In a third experiment, aged rats were unimpaired in the ability to perform in a T-maze task involving a brightness discrimination with intramaze cues. This result suggests that the age-related impairment in the two-component T-maze task was restricted to the cognitive demands of the task. Neurochemical analyses were performed to determine whether regional neurotransmitter synthetic enzyme activities could be used to identify neurochemical systems associated with performance in these tasks and with any age-related impairments observed. Choline acetyltransferase and glutamic acid decarboxylase were assayed as markers for cholinergic and GABAergic systems, respectively, in the hippocampi and the following cortical regions: frontal, sensorimotor, auditory, cingulate, occipital, and pyriform-perirhinal. A slight (8%) but significant age-related decline was observed in the activity of glutamic acid decarboxylase but not of choline acetyltransferase. Although the correlation between maze performance and regional enzyme activities generally supported several previous observations, the only significant correlation to emerge was between working memory performance and glutamic acid decarboxylase activity in the cingulate cortex. 相似文献
147.
We studied whether volunteers giving blood to the Greater New York Blood Program (GNYBP) cooperated with procedures implementing public health recommendations intended to decrease the risk of acquired immunodeficiency syndrome (AIDS) transmission by blood transfusion. Predonation medical screening was expanded to exclude donors who might be ill with AIDS. To exclude possible asymptomatic carriers of the disease, members of groups at increased risk of AIDS were asked either not to give blood or to give it for laboratory studies. A confidential questionnaire, administered to all donors after medical screening, provided the vehicle for donors to advise the GNYBP whether their donation was for laboratory studies or for patient transfusion. We found that the number of male donors decreased; AIDS-related questions in medical history led to a 2 percent increase in donor rejections; 97 percent of donors said their blood could be used for transfusions; 1.4 percent said their blood could be used for laboratory studies only; and 1.6 percent did not respond. Only units designated for transfusion were released to hospitals. People who indicated that their donation was for laboratory studies had a higher prevalence of markers for hepatitis B virus and of antibodies to cytomegalovirus. White cell counts and helper/suppressor T lymphocyte ratios were not significantly different in the two groups. We conclude that volunteer donors have cooperated with the established procedures. None of the laboratory assays identified blood units donated by individuals who, based on information about AIDS high-risk groups, designated their donation for laboratory studies. 相似文献
148.
To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tensile stresses may be imposed on the surface of the plate. This condition is violated when stairs are attached to the plates, unless the plates are preloaded. Typical shear forces encountered when climbing stairs were used to determine required preloads of approximately 16.4 N/cm step height. Vertical and horizontal loads were applied at known locations on the steps, and points of application were calculated. Deviations were within ± 3 mm. The effect of point of application inaccuracy on calculated joint moments is considerable. A 2 cm medial shift in the point of application resulted in calculated peak knee abduction/adduction moment errors of 35%. 相似文献
149.
Glucose reflectance meters equipped with memories were used in 21 insulin-dependent diabetic patients to assess reliability of self blood glucose monitoring records. Results reported in logbooks showed widespread discrepancies when compared with corresponding meter-held records. Discrepancy rates of at least one in five were observed in 11 patients. Unreliable reporting was usually recognized by clinical staff, and associated with high glycosylated haemoglobin levels and poor technique in measuring blood glucose at home. 相似文献
150.
Gray-scale sonographic spectrum of hypernephromas 总被引:1,自引:0,他引:1