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91.
92.
Composite tissue (limb) allografts in rats. III. Development of donor-host lymphoid chimeras in long-term survivors 总被引:2,自引:0,他引:2
C W Hewitt K S Black S F Dowdy G A Gonzalez B M Achauer D C Martin D W Furnas E B Howard 《Transplantation》1986,41(1):39-43
Eight LEW rat recipients possessing long-term-surviving (206-701 days) LBN vascularized hind limb allografts (CTAs) were tested for donor-host lymphoid chimerism. The recipients received various cyclosporine (CsA) treatment protocols in order to induce indefinite CTA acceptance. Histological examination of long-term-surviving CTAs demonstrated normal-appearing bone marrow in the donor limb. Lymphocytes isolated from host hemopoietic tissues (peripheral blood and/or spleen) by ficoll-hypaque density gradient centrifugation were tested against LEW-anti-BN antisera. Comparisons were made to standard curves employing various known concentrations of LBN and LEW cell combinations. The level of lymphocyte agglutination (dependent variable) showed a significant (P less than 0.025-0.005) linear relationship to the concentration of LBN donor cells (independent variable) present. Lymphocyte suspensions isolated from long-term CTA host peripheral blood and/or spleen showed a mean of 19.7% (+/- 9.7-95% confidence interval) donor LBN mononuclear cells present. Thus, it appeared that lymphoid cells originated from, and/or were released from LBN donor bone marrow into the circulation, resulting in chimeric repopulation of hemopoietic tissues. The presence of donor immunocytes in these limb allograft recipients may have been beneficial, and thus could have helped contribute to the long-term CTA survival observed. 相似文献
93.
94.
D R Black 《Journal of behavior therapy and experimental psychiatry》1988,19(2):103-111
This study investigated the difference in weight changes of subjects who rated their marriages as more adjusted vs subjects who rated their marriages as less adjusted. Twenty-six moderately obese subjects were assigned to one of two groups based on their initial scores on the Locke-Wallace Marital Adjustment Scale (MAS). The 10 subjects in the "moderately unhappy" group (MAS less than or equal to 99) lost significantly more weight than the 16 subjects in the "relatively happy" group (MAS greater than or equal to 100) at the end of the one-year treatment program (29.9 lb vs 20.4 lb) and at 3-month follow-up (27.7 lb vs 17.8 lb). Significantly more subjects in the unhappy group also reached ideal weight than subjects in the happy group (50% vs 7.7%). Subjects' initial MAS scores were significantly and negatively correlated with weight changes at post-treatment and follow-up; partners' MAS scores at the end of treatment were also significantly and negatively correlated to subjects' weight losses at post-treatment. None of the couples was initially maritally distressed but one couple met this criterion (MAS less than or equal to 85) by the end of treatment and follow-up. It was concluded that marital counseling is not a prerequisite for weight counseling, couples' marital adjustment does not improve as the subject loses weight and a moderate level of marital dissatisfaction does not seem to be an insurmountable barrier to successful weight loss and may be an advantage for some individuals. 相似文献
95.
In a case-control study, 57 manics with antecedent or coexisting nonaffective psychiatric disorders (n = 38) or serious medical illnesses (n = 19) ("complicated mania") were compared with 114 age-, sex-, and year-of-admission-matched controls with no other disorder ("uncomplicated mania"). Significant differences emerged between the three groups in age, marital status, age at onset, number of prior hospitalizations and prior suicide attempts, organic features, and outcome measures (recovery and death rates). Patients were divided into four treatment groups based on primary mode of therapy during index admission; the groups included electroconvulsive therapy, adequate lithium carbonate, inadequate lithium carbonate, and neither treatment. Uncomplicated manics were significantly more likely to receive adequate lithium carbonate and less likely to receive inadequate lithium carbonate than were complicated manics. The latter patients had a significantly poorer immediate response to treatment overall, and to adequate lithium carbonate specifically. Seventy-eight (68.4%) uncomplicated manics had recovered ad discharge, compared with 26 (45.6%) complicated manics. Logistic regression suggested that the influence of comorbidity on outcome was more important for women than men. We conclude that complicated mania is a useful clinical construct. 相似文献
96.
It has been estimated that 30% to 70% of children who are diagnosed as having attention-deficit hyperactivity disorder (ADHD) will continue to show symptoms of the condition as adults. Since the prevalence of ADHD among school children may be 3% or more, its prevalence among adults may be 1% or 2%. The third revised edition of the Diagnostic and Statistical Manual (1987) of the American Psychiatric Association lists three essential features for the diagnosis of ADHD: "developmentally inappropriate inattention, impulsiveness, and hyperactivity." Other conditions associated with ADHD in adults include learning disabilities (or their sequelae), general anxiety disorder, drug and alcohol abuse, and dysthymic and cyclothymic disorders. Strong correlations have been found between ADHD and oppositional defiant and conduct disorders in children and an increased risk for antisocial disorders in adults. A combination of genetic, biologic, and environmental factors appears to be implicated in the etiology of ADHD. The management of adult ADHD requires a multimodal approach. The patient needs to be informed of the cause of his or her impulsive and often self-destructive behavior. Many patients will have learning difficulties that require evaluation and remediation by specialists in learning disabilities. Psychotherapy can help the patients resolve disturbances in perceptions of self and others and family therapy can address difficulties in the adult's relationships with family members. Pharmacotherapy of adult ADHD includes the use of central nervous system stimulants, such as methylphenidate, dextroamphetamine, and pemoline, of the tricyclic antidepressants imipramine and desimipramine, and of other antihypertensive, analgesic, and antimanic drugs. 相似文献
97.
S H Black M Z Pelias J B Miller M G Blitzer E Shapira 《American journal of medical genetics》1986,25(2):273-279
We describe a large consanguineous German-Acadian ("Cajun") family from a rural area in Louisiana in which 11 persons in two generations had the Maroteaux-Lamy syndrome. The mutant arylsulfatase B enzyme in this family was similar to the mutant enzyme in previously studied families in its cross-reactivity with specific antibodies to the enzyme, but it differed in both its electrophoretic mobility and its residual enzymatic activity. These findings indicate that a different mutational event leading to Maroteaux-Lamy syndrome occurred in this family. 相似文献
98.
Delayed pressure urticaria is a mechanical urticaria in which pressure causes whealing. Delayed cutaneous erythema and edema occur in association with marked subcutaneous swelling after the application of a sustained pressure stimulus to the skin. The earliest reports and theories of the pathogenesis of delayed pressure urticaria are summarized. Detailed attention is given to making the diagnosis by taking a history and provoking the lesions. The clinical features and natural history are considered. The effects of the disorder on quality of life are delineated, and management strategies are suggested. 相似文献
99.
100.
Dynamic Mechanical Conditioning of Collagen-Gel Blood Vessel Constructs Induces Remodeling In Vitro 总被引:11,自引:0,他引:11
Dynamic mechanical conditioning is investigated as a means of improving the mechanical properties of tissue-engineered blood vessel constructs composed of living cells embedded in a collagen-gel scaffold. This approach attempts to elicit a unique response from the embedded cells so as to reorganize their surrounding matrix, thus improving the overall mechanical stability of the constructs. Mechanical conditioning, in the form of cyclic strain, was applied to the tubular constructs at a frequency of 1 Hz for 4 and 8 days. The response to conditioning thus evinced involved increased contraction and mechanical strength, as compared to statically cultured controls. Significant increases in ultimate stress and material modulus were seen over an 8 day culture period. Accompanying morphological changes showed increased circumferential orientation in response to the cyclic stimulus. We conclude that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization. This concept, in conjunction with a proper biochemical environment, could present a better model for engineering vascular constructs. © 2000 Biomedical Engineering Society.
PAC00: 8719Rr, 8714Ee, 8718-h, 8768+z 相似文献