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121.
INTRODUCTION: A broad range of psychopathology, including externalizing disorders is seen in offspring at genetic risk for schizophrenia. However, it is unclear whether such psychopathology may underlie a higher predisposition to the premorbid antecedents of schizophrenia. We examined the prevalence and correlates of psychopathology in an ongoing study of offspring genetically at risk for schizophrenia. METHODS: Seventy five consenting high risk offspring (HR: offspring, age 15.68+/-3.27 years; male/female 34/41) and 82 matched comparison subjects (40 males and 42 females; age 15.92+/-3.0 years) participated in this study. Diagnoses were ascertained using structured psychiatric interviews and consensus meetings, including all available clinical information. RESULTS: Sixty (60%) of the HR offspring had one or more lifetime diagnosis of axis I psychiatric disorder. HR subjects with axis I psychopathology had significantly more soft neurological signs, poorer premorbid adjustment, and higher schizotypy scores as measured by Chapman psychosis proneness scales. Among those with psychopathology, HR subjects with externalizing disorders showed the most abnormal scores in schizotypy. DISCUSSION: A substantial proportion of HR offspring of parents with schizophrenia manifest a broad range of childhood psychiatric disorders. Psychopathology, especially externalizing disorders such as attention deficit hyperactivity disorder (ADHD) may represent a subgroup with an increased risk for schizophrenia spectrum disorders. This possibility needs to be examined by prospective follow-up studies, and would be of considerable importance to early diagnosis and intervention efforts in schizophrenia.  相似文献   
122.
The genome of Mycobacterium tuberculosis contains a large number of hypothetical and poorly characterized proteins including the proteins belonging to the GntR family. The regulators of this family show a conserved N-terminal DNA-binding domain but have a highly diverse C-terminal domain involved in the effector-binding and/or oligomerization. This heterogeneity has led to a further classification of this family into various subfamilies. The sequence analysis of the M. tuberculosis genome revealed that five genes encode for FadR-like regulators, one gene for HutC-like regulator and one for YtrA-like regulator. This classification was also consistent with specific secondary structural features known to be associated with FadR, HutC and YtrA subfamilies. Out of the five FadR-like regulators three of the regulators were further subclassified into FadR group and two of them into the VanR group. Interestingly Rv3060c, a FadR-like regulator, was shown to have an unusual size which led us to demonstrate it as a product of a gene duplication and fusion event. Thus this study extends the genome annotation of M. tuberculosis and provides important leads for initiating experimental characterization of these proteins, which in turn will enrich our knowledge of their role in cellular physiology.  相似文献   
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124.
Background:  Increased susceptibility for developing alcohol dependence (AD) may be related to structural and functional differences in brain circuits that influence social cognition and more specifically, theory of mind (ToM). Alcohol dependent individuals have a greater likelihood of having deficits in social skills and greater social alienation. These characteristics may be related to inherited differences in the neuroanatomical network that comprises the social brain.
Methods:  Adolescent/young adult participants from multiplex AD families and controls ( n  = 16) were matched for gender, age, IQ, education, and handedness and administered the Eyes Task of Baron-Cohen during functional magnetic resonance imaging (fMRI).
Results:  High-risk (HR) subjects showed significantly diminished blood oxygen level dependent (BOLD) response in comparison with low-risk control young adults in the right middle temporal gyrus (RMTG) and the left inferior frontal gyrus (LIFG), areas that have previously been implicated in ToM tasks.
Conclusions:  Offspring from multiplex families for AD may manifest one aspect of their genetic susceptibility by having a diminished BOLD response in brain regions associated with performance of ToM tasks. These results suggest that those at risk for developing AD may have reduced ability to empathize with others' state of mind, possibly resulting in diminished social skill.  相似文献   
125.
To determine whether herpes simplex virus type 1 (HSV-1) infection causes oxidative stress and lipid peroxidation in cultured neural cells, mouse P19 embryonal carcinoma cells were differentiated into cells with neural phenotypes (P19N cells) by retinoic acid and were then infected with HSV-1. Cellular levels of reactive oxygen species (ROS) and the release of lipid peroxidation by-products into the tissue culture medium were then measured by the generation of fluorescent markers hydroxyphenyl fluorescein and a stable chromophore produced by lipid peroxidation products, malondialdehyde (MDA) and hydroxyalkenals (4-HAEs; predominantly 4-hydroxy-2-nonenal [HNE]), respectively. HSV-1 infection increased ROS levels in neural cells as early as 1 h post infection (p.i.) and ROS levels remained elevated at 24 h p.i. This viral effect required viral entry and replication as heat- and ultraviolet light-inactivated HSV-1 were ineffective. HSV-1 infection also was associated with increased levels of MDA/HAE in the culture medium at 2 and 4 h p.i., but MDA/HAE levels were not different from those detected in mock infected control cultures at 1, 6, and 24 h p.i. HSV-1 replication in P19N cells was inhibited by the antioxidant compound ebselen and high concentrations of HNE added to the cultures, but was increased by low concentrations of HNE. These findings indicate that HSV-1 infection of neural cells causes oxidative stress that is required for efficient viral replication. Furthermore, these observations raise the possibility that soluble, bioactive lipid peroxidation by-products generated in infected neural cells may be important regulators of HSV-1 pathogenesis in the nervous system.  相似文献   
126.
Aim: To evaluate the effect of ozonated oil on palatal wounds. Methods: Eighteen patients were randomized and allocated to either the ozone group (n = 8) or control (n = 10) group. Free gingival graft surgery was performed, and post‐harvested palatal wounds were treated with either 2 mL ozonated oil or control oil daily for 1 week. A planimetrical analysis analyzed the digital image for the wound sizes and shape factor at baseline, at 24 h, and days 5, 7, 14, 21, and 28, postoperatively. A cytological analysis used the keratinization and superficial cell indices at baseline, 24 h, and days 3, 7, 14, and 21 and the second and third months, postoperatively. Results: Planimetrical results showed a significant (P ≤ 0.05) improvement in wound size on days 5, 7, 14, 21, and 28, postoperatively, in the ozone group compared to the control group. Cytological results showed a significant (P ≤ 0.001) improvement in epithelial healing on days 7, 14, and 21, and the second and third months, postoperatively, after the application of ozonated oil compared to control oil. Conclusion: Our results showed significant improvement in wound size and epithelial healing after topical ozonated oil application compared to control oil on palatal wounds.  相似文献   
127.
Thrombocytopenia is an uncommon but potentially life-threatening complication of certain antitubercular drugs and is characterized by rapid destruction of platelets whenever offending drug is taken by a susceptible person. We report a case of pyrazinamide-induced thrombocytopenia in a patient receiving anti tubercular drugs.  相似文献   
128.
We report on the transabdominal resection of infected lumbosacral bone, synthetic mesh, and sinus tract following sacral colpopexy. A 45-year-old nulliparous patient who had undergone transvaginal mesh followed by robot-assisted sacral colpopexy presented with increasing back pain and foul-smelling vaginal drainage. An epidural abscess required surgical intervention, including diskectomy, sacral debridement, and mesh removal to drain the abscess and vaginal sinus tract. Recognized complications of open prolapse procedures also manifest following minimally invasive approaches. Osteomyelitis of the sacral promontory following sacral colpopexy may require gynecologic and neurosurgical management.  相似文献   
129.
Adenosine has been suggested to induce bronchial hyperresponsiveness in asthmatics, which is believed to be an A(2B) adenosine receptor (AdoR) mediated pathway. We hypothesize that a selective, high-affinity A(2B) AdoR antagonist may provide therapeutic benefit in the treatment of asthma. In an attempt to identify a high-affinity, selective antagonist for the A(2B) AdoR, we synthesized 8-(C-4-pyrazolyl) xanthines. Compound 22, 8-(1H-pyrazol-4-yl)-1,3-dipropyl xanthine, is a N-1 unsubstituted pyrazole derivative that has favorable binding affinity (K(i) = 9 nM) for the A(2B) AdoR, but it is only 2-fold selective versus the A(1) AdoR. Introduction of a benzyl group at the N-1-pyrazole position of 22 resulted in 19, which had moderate selectivity. The initial focus of the SAR study was on the preparation of substituted benzyl derivatives of 19 because the corresponding phenyl, phenethyl, and phenpropyl derivatives showed a decrease in A(2B) AdoR affinity and selectivity relative to 19. The preferred substitution on the phenyl ring of 19 contains an electron-withdrawing group, specifically F or CF(3) at the m-position, as in 33 and 36 respectively, increases the selectivity while retaining the affinity for the A(2B) AdoR. Exploring disubstitutions on the phenyl ring of derivatives 33 and36 led to the 2-chloro-5-trifluoromethylphenyl derivative 50, which retained the A(2B) AdoR affinity but enhanced the selectivity relative to 36. After optimization of the substitution on the 8-pyrazole xanthine, 1,3-disubstitution of the xanthine core was explored with methyl, ethyl, butyl, and isobutyl groups. In comparison to the corresponding dipropyl analogues, the smaller 1,3-dialkyl groups (methyl and ethyl) increased the A(2B) AdoR binding selectivity of the xanthine derivatives while retaining the affinity. However, the larger 1,3-dialkyl groups (isobutyl and butyl) resulted in a decrease in both A(2B) AdoR affinity and selectivity. This final SAR optimization led to the discovery of 1,3-dimethyl derivative 60, 8-(1-(3-(trifluoromethyl) benzyl)-1H-pyrazol-4-yl)-1,3-dimethyl xanthine, a high-affinity (K(i) = 1 nM) A(2B) AdoR antagonist with high selectivity (990-, 690-, and 1,000-) for the human A(1), A(2A,) and A(3) AdoRs.  相似文献   
130.
Viruses are well known for their ability to cause disease, but their beneficial usefulness as vectors for gene therapy have been noted as well. As an extension of their use in a gene therapy context, their combination with nanotechnology is starting to benefit many areas of science and medicine. These include nanofabrication and medical diagnostics, to name a few, as well as viro-nanotherapy, here defined as the combination of viral biology with nanotechnology to create new therapeutic avenues to treat disease. This review provides examples of areas wherein viruses in combination with nanotechnology are being used to either advance scientific knowledge or accelerate the development of new diagnostics and therapeutics for human pathological conditions.  相似文献   
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