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21.
Streptococcus mutans is a key bacterium in dental caries, one of the most prevalent chronic infectious diseases. Conventional treatment fails to specifically target the pathogenic bacteria, while tending to eradicate commensal bacteria. Thus, caries remains one of the most common and challenging diseases. Phage therapy, which involves the use of bacterial viruses as anti-bacterial agents, has been gaining interest worldwide. Nevertheless, to date, only a few phages have been isolated against S. mutans. In this study, we describe the isolation and characterization of a new S. mutans phage, termed SMHBZ8, from hundreds of human saliva samples that were collected, filtered, and screened. The SMHBZ8 genome was sequenced and analyzed, visualized by TEM, and its antibacterial properties were evaluated in various states. In addition, we tested the lytic efficacy of SMHBZ8 against S. mutans in a human cariogenic dentin model. The isolation and characterization of SMHBZ8 may be the first step towards developing a potential phage therapy for dental caries.  相似文献   
22.
In the 1359 published patients with multiorgan cholesterol crystal embolism (CCE), the digestive system seems to be the third most frequently affected system. Yet, this system received hitherto only little attention in the medical literature. Therefore, the aim of the present study was to clinically characterize the subset of patients with CCE involving the digestive system, based on our institutional experience and a review of the literature. Cases with CCE in a 7-yr period (1995-2001) were sought in the computerized records of our medical center. Of the CCE patients, those with digestive system involvement that could be related to CCE were included in this study. The clinical features of CCE were determined and compared with those found in published series. Fourteen cases with CCE were identified, giving an annual incidence of 0.8 per 10(5). Digestive system involvement was found in five (36%) of the 14 patients. All five patients had established atherosclerosis. Precipitating factors were vascular manipulations or anticoagulation treatment in four of these five patients. Two patterns of disease appeared: acute catastrophic multiorgan disorder with poor prognosis and chronic and more indolent GI disease. Abdominal pain, GI bleeding, fever, and diarrhea were the most common manifestations, resulting from bowel infarction, mucosal ulcerations, hepatocellular liver disorder, and/or pancreatitis. CCE is a systemic disorder with a frequent involvement of the digestive system and protean clinical manifestations. It should, therefore, be considered in any gastroenterological patient with atherosclerosis and recent vascular manipulations or systemic anticoagulation.  相似文献   
23.
Summary. Chronic lymphocytic leukaemia (CLL) is known to be a stable monoclonal neoplasm. In contrast to early studies demonstrating no more than two hybridizing immunoglobulin heavy chain bands corresponding to the two expected alleles, we have demonstrated an unexpected multiband pattern when the HindIII-digested DNA samples from 38 CLL patients were analysed by Southern blot hybridization using JH and Cμ gene probes. In order to characterize the genetic basis for the multiband pattern, we molecularly cloned the immunoglobulin heavy chain genes of one of the patients whose leukaemic DNA sample demonstrated three hybridizing JH bands and a loss of the germline band. The cloned rearranged immunoglobulin genes could be divided, based on the restriction mapping and the hybridization with the various probes, into two basic patterns representing two alleles. In one of the cloned rearranged immunoglobulin genes a secondary rearrangement occurred that resulted in the addition of 300 base-pair long sequence into the switch region, and the creation of a HindIII restriction site.
The results of the study suggest that clonal evolution occurs in some CLL, and that many of these neoplasms are indeed oligoclonal due to the accumulation of secondary genetic changes.  相似文献   
24.
Background: Elevation of acute phase proteins [C-reactive protein (CRP) and serum amyloid type A (SAA)] has been demonstrated in unstable angina with an adverse clinical prognosis. Hypothesis: The study was undertaken to determine the effect of angioplasty on the levels of SAA and the correlation with postangioplasty restenosis. Methods: In a university-affiliated tertiary medical center, a prospective case study was undertaken in 55 patients who underwent successful percutaneous transluminal coronary angioplasty (PTCA) of a single coronary lesion for angina pectoris. Three groups of patients were clinically characterized according to Braunwald's classification of anginal syndrome: Group A: class III; Group B: class I; Group C: stable angina. Serum amyloid type A was measured by an ELISA method before PICA and after 24 h, 1, and 3 months. Patients were followed clinically for 12 months. A thallium stress perfusion scan was performed 3 months after PTCA and coronary angiography was repeated in patients with an abnormal thallium perfusion scan. Results: Serum amyloid type A levels >100 m?/ml could identify Group A patients with a high sensitivity and specificity (r = 0.85 and 0.86, respectively). Of the patients studied. 75% increased their SAA level 24 h after angioplasty. An increase of SAA by >100% was associated with an increased risk of restenosis, with a relative risk of 6.4 (p < 0.05). Conclusion: Increased levels of SAA characterize patients with unstable angina pectoris with a high specificity and sensitivity. Levels of SAA that increase > 100% 24 h after angioplasty may serve as a marker of restenosis.  相似文献   
25.
White‐Sutton syndrome (WHSUS) is a recently‐identified genetic disorder resulting from de novo heterozygous pathogenic variants in POGZ. Thus far, over 50 individuals have been reported worldwide, however phenotypic characterization and data regarding the natural history are still incomplete. Here we report the clinical features of 22 individuals with 21 unique loss of function POGZ variants. We observed a broad spectrum of intellectual disability and/or developmental delay with or without autism, and speech delay in all individuals. Other common problems included ocular abnormalities, hearing loss and gait abnormalities. A validated sleep disordered breathing questionnaire identified symptoms of obstructive sleep apnea in 4/12 (33%) individuals. A higher‐than‐expected proportion of cases also had gastrointestinal phenotypes, both functional and anatomical, as well as genitourinary anomalies. In line with previous publications, we observed an increased body mass index (BMI) z‐score compared to the general population (mean 0.59, median 0.9; p 0.0253). Common facial features included microcephaly, broad forehead, midface hypoplasia, triangular mouth, broad nasal root and flat nasal bridge. Analysis of the Baylor Genetics clinical laboratory database revealed that POGZ variants were implicated in approximately 0.14% of cases who underwent clinical exome sequencing for neurological indications with or without involvement of other body systems. This study describes a greater allelic series and expands the phenotypic spectrum of this new syndromic form of intellectual disability and autism.  相似文献   
26.
The purpose of this study was to evaluate the prevalence of chronic health conditions in the Russian population who immigrated to Israel during 1989–1992. Interviewer-supported self-administered questionnaires were distributed to a 50% random sample of 1710 immigrants residing in the city of Nazareth-Ilit in Northern Israel. The final study group included 897 adults after a 3.5% of noncompliance. The study participants were asked to report all chronic diseases from a list of 11 disease states. The data were coupled with their demographic data and are presented as age/sex-specific prevalence rates. Self-reported disease prevalence rates among the Russian immigrants to Israel were found to be very high (62.2% of the males and 68.7% of the females reported a mean 3–3.5 diseases per person). These reported rates were significantly higher for immigrants from the European republics (67.1%) than for those from Asian republics (55.6%). The highest reported age-specific disease prevalence rates were for musculoskeletal diseases (389/1000), ischemic heart disease (340/1000), gastrointestinal diseases (269/1000), and hypertension (226/1000). A higher rate among females was found for almost all disease states. The prevalence rates reported by the Russian Jews in this study are much higher than commonly observed in Western countries. This is in accordance with a similar difference in reported mortality rates between Western countries and the former USSR. The etiologic explanation of this finding is yet to be studied. In addition, and in light of the mass immigration of Eastern European residents to the West it is of major importance for local health authorities to respond appropriately to the differences in health status of these immigrating populations.  相似文献   
27.
Following injury, as part of the wound-healing process, cell proliferation occurs mostly to replace damaged cells and to reconstitute the tissue back to normal condition/function. In the spinal cord some of the dividing cells following injury interfere with the repair processes. This interference occurs at the later stages of wound healing (the third week after injury) triggering chronic inflammation and progressive tissue decay that is the characteristic pathology of spinal cord injury. Specific cell elimination within a critical time window after injury can lead to repair in the acutely injured spinal cord. Cell proliferation events can be manipulated/modified by x-irradiation. Clinically, numerous radiation protocols (i.e., radiation therapy) have been developed that specifically eliminate the rapidly dividing cells without causing any noticeable/significant damage to the tissue as a whole. Radiation therapy when applied within the critical time window after injury prevents the onset of chronic inflammation thus leading to repair of structure and function. Various aspects of the development of this cell-elimination strategy for repair in acute spinal cord injury by utilizing radiation therapy are being reviewed. Topics reviewed here: identifying the window of opportunity; and the beneficial repair effects of radiation therapy in a transection injury model and in a model relevant to human injury, the contusion injury model. The possible involvement of cellular components of the blood-spinal cord barrier as the trigger of chronic inflammation and/or target of the radiation therapy is discussed.  相似文献   
28.
29.
Background: The causal relationship between obesity and osteoarthritis (OA) of the knee is generally accepted. Weight loss has been shown to reduce the development of OA and improve the radiological parameters of existing disease. However, inducing weight reduction is difficult, and thus the number of patients studied has been small. We wished to determine the effects of surgically-induced weight loss on objective, radiological evidence of OA in the knee joint. Methods: 64 consecutive patients that were referred to the Bariatric Surgical Unit were enrolled in the study. The only exclusion criterion was the prior diagnosis of OA. Knee pain alone did not exclude patients from the study. The study was performed in a prospective manner as a before-after trial. Radiographic data was evaluated by an independent radiologist not involved in the patient care or follow-up. Upright film of the knee was taken prior to surgery and 3 months following surgery. Minimal medial joint space width (JSW) was measured by a digital image computer. In addition, patients were clinically assessed using the American Knee Society Score (AKSS) at these times. Results: 59 of 64 patients were available for followup. BMI decreased from 43.4 to 36.9 (P<0.01). The medial joint space increased from 4.6 mm to 5.25 mm (P<0.001). The AKSS improved from 78.5 points (perfect function = 100 points) to 90.69 points (P<0.01). Conclusion: Surgically-induced weight loss is an effective, rapid and dependable means of reversing the radiological signs of early changes associated with OA.  相似文献   
30.
Since 9/11, hospitals and health authorities have been preparing medical response in case of various mass terror attacks. The experience of Tel Aviv Sourasky Medical Center in treating suicide-bombing mass casualties served, in the time leading up to the war in Iraq, as a platform for launching a preparedness program for possible attacks with biological and chemical agents of mass destruction. Adapting Quarantelli's criteria on disaster mitigation to the "microinfrastructure" of the hospital, and including human behavior experts, we attempted to foster an interactive emergency management process that would deal with contingencies stemming from the potential hazards of chemical and biological (CB) weapons. The main objective of our work was to encourage an organization-wide communication network that could effectively address the contingent hazards unique to this unprecedented situation. A stratified assessment of needs, identification of unique dangers to first responders, and assignment of team-training sessions paved the way for program development. Empowerment through leadership and resilience training was introduced to emergency team leaders of all disciplines. Focal subject matters included proactive planning, problem-solving, informal horizontal and vertical communication, and coping through stress-management techniques. The outcome of this process was manifested in an "operation and people" orientation supporting a more effective and compatible emergency management. The aim of article is to describe this process and to point toward the need for a broad-spectrum view in such circumstances. Unlike military units, the civilian hospital staff at risk, expected to deal with CB casualties, requires adequate personal consideration to enable effective functioning. Issues remain to be addressed in the future. We believe that collaboration and sharing of knowledge, information, and expertise beyond the medical realm is imperative in assisting hospitals to expedite appropriate preparedness programs.  相似文献   
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