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1.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight.  相似文献   
2.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
3.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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4.
Alopecia areata is an inflammatory hair loss disease with a major genetic component. The presence of focal inflammatory lesions with perifollicular T‐cell infiltrates reflects the importance of local cytokine production in the pathogenesis. In addition to its fundamental pro‐inflammatory role, the interleukin‐1 (IL‐1) system has major effects on hair growth regulation in vitro, with the inhibitory actions of IL‐1α and IL‐1β being opposed by the receptor antagonist IL‐1ra. The novel interleukin‐1 like molecule 1 (IL‐1L1) which has greatest gene sequence homology with IL1RN, the gene encoding IL‐1ra, is another potential IL‐1 antagonist. In view of previous studies suggesting a significant role for IL1RN polymorphisms in the pathogenesis of autoimmune/inflammatory disease, we have analysed polymorphisms of IL‐1ra (IL1RN+2018) and its homologue IL‐1L1 (IL1L1+4734) in a case–control association study on 165 patients and a large number of matched controls. Homozygosity for the rare allele of IL1RN (IL1RN*2) was significantly associated with alopecia areata [odds ratio (OR) = 1.89, 95% CI (1.09, 3.28); P = 0.02], confirming our previous findings of significant association with the IL1RN variable number tandem repeat (VNTR). The results also revealed a novel association involving a polymorphism of the interleukin‐1 receptor antagonist homologue IL1L1 at position + 4734, IL1RN+2018, and alopecia areata. The effect of a genotype combining three copies of the rare alleles at the IL1RN and IL1L1 loci conferred a more than additive increase in the risk of disease compared to IL1RN+2018 or IL1L1+4734 alone [OR 3.37 (1.60, 7.06); P = 0.002], suggesting possible synergy between the IL1RN and IL1L1 genes. This effect was stronger in patients with severe disease (alopecia totalis/universalis) [OR 4.62 (1.87, 11.40), P = 0.0022], and in those with early age at onset (< 20 years) [OR = 6.38 (2.64, 15.42), P = 0.0002]. Our results suggest that these polymorphisms within IL1RN and IL1L1 themselves or a gene in linkage disequilibrium with IL1RN and IL1L1 predispose to the more severe forms of alopecia areata.  相似文献   
5.
6.
To study the function of the protooncogene Mos in mouse brain development we have created a transgenic mouse model system in which an activated form of the gene, the murine retroviral v-Mos gene, is highly overexpressed in the brain. Six transgenic founder animals and mice of one established transgenic line (line TG66) displayed a progressive hind limb paralysis with onset between 18 days and 9 months. The severity of the neurological phenotype correlated with pathological alterations and the degree of v-Mos expression in the brain which varied between individual animals of line TG66. The most striking feature of the brain pathology was the presence of large, abnormal astrocytes in the cerebellum, medulla, thalamus and in the dorsal horn of the spinal cord. These areas also contained shrunken and basophilic neurons whose cytoplasm was abnormally immunoreactive for phosphorylated epitopes of neurofilaments. In addition to neuropathologic changes, these mice also displayed aberrant eye lens differentiation and absence of hair cells in the inner ear. These results establish v-Mos transgenic mice as a model system to study progressive neurodegenerative disease and provide further evidence that the Mos protein-serine/threonine kinase has a function in brain development.  相似文献   
7.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.  相似文献   
8.
Verbal paired associates were presented to 25 surgical patients from initial incision to closure of the incision during general anesthesia. Sufentanil with nitrous oxide and oxygen was administered; intravenous morphine (0.05 mg/kg) was administered when the skin suturing was completed; no volatile anesthetic agents or benzodiazepines were administered. When ready for discharge from the postanesthesia care unit, and again 2 weeks later by telephone, patients were tested for free recall, cued recall, recognition, and free association. No evidence of explicit memory for the word list was demonstrated by patients on tests of free recall, cued recall, or recognition, nor did a free-association test of implicit memory demonstrate a significant priming effect, in contrast to previous results obtained with isoflurane. The precise conditions under which surgical events can be processed, and retained in the form of implicit memory outside of conscious awareness, remain to be determined.  相似文献   
9.
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.  相似文献   
10.
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed.  相似文献   
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