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The occurrence of graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation for leukemia is thought to decrease the probability of recurrence. To study this effect (called adoptive immunotherapy) we modified the prophylaxis of GVHD in patients with advanced hematologic neoplasms (mostly leukemia) who received bone marrow transplants. Patients under 30 years of age were randomly assigned to one of three regimens of post-transplantation immunosuppression: Group I (n = 44) received a standard course of methotrexate for 102 days after transplantation, Group II (n = 40) received an abbreviated (11-day) course of methotrexate, and Group III (n = 25) received the standard course of methotrexate plus viable buffy-coat cells from the marrow donors. All 109 patients received cyclophosphamide (60 mg per kilogram of body weight on each of two days), total-body irradiation (2.25 Gy daily for seven days), and unmodified marrow from HLA-identical sibling donors. The frequency of GVHD of Grades II through IV was 25 percent in Group I, 59 percent in Group II, and 82 percent in Group III (P = 0.0001). The incidence of chronic GVHD, however, did not differ significantly among the groups (33, 51, and 44 percent, respectively), nor did the five-year probability of recurrence of disease (38, 45, and 33 percent, respectively). However, mortality from causes other than cancer was 34 percent in Group I, 45 percent in Group II, and 64 percent in Group III (I vs. III, P = 0.024); the deaths were due primarily to infections complicating the course of GVHD. With a median follow-up of 5.1 years (range, 3.9 to 7.4), disease-free survival was 41 percent in Group I, 30 percent in Group II, and 24 percent in Group III (the differences were not statistically significant). We conclude that abbreviating methotrexate prophylaxis or infusing donor buffy-coat cells increased the incidence of acute GVHD and related mortality without altering the incidence of chronic GVHD or the recurrence of malignant disease.  相似文献   
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Fire departments have replaced traditional uniforms with modern, more thermal protective gear. Although the new uniforms afford superior burn protection, they may reduce work time. Our purpose was to determine if exercise time was (1) reduced by wearing the modern versus traditional uniform, and (2) increased by a design change to a modified modern uniform (T-shirt and short pants rather than a shirt and long pants under the outer uniform). Male firefighters (n = 23; age 27 to 59) performed a maximum exercise test in gym clothes (maximal oxygen consumption = 46 +/- 9 ml/kg/min) and then returned on separate days to exercise using a moderately high intensity, constant work rate treadmill protocol while wearing fire fighting breathing apparatus and each of three uniforms. Firefighters exceeded anaerobic threshold by 1 minute and eventually reached or exceeded maximum heart rate and maximal oxygen consumption. Exercise time in modern (15 +/- 3 min) was significantly less than in traditional (18 +/- 5 min) uniform. Exercise time in modified modern (17 +/- 5 min) was significantly greater than in modern and not significantly different than in traditional uniforms. The rate of change in oxygen consumption and water loss were significantly affected by uniform type, with faster rates in modern compared with modified modern or traditional uniforms. These findings show the impact that design changes have on energy demands and exercise duration.  相似文献   
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Marrow transplants were carried out between unrelated donor-recipient pairs of dogs that were homozygous and identical for DLA-A, B, C, and D, i.e., mutually nonreactive in mixed leukocyte culture. Recipients were conditioned for transplantation by 1,200 R of total body irradiation and then treated with intermittent methotrexate for 102 days in order to prevent or delay graft-versus-host disease (GVHD). Of 13 dogs that received transplants, 4 are surviving with good grafts and no GVHD for more than 12 to 20 minutes. Nine died, 6 with GVHD between days 26 and 141, 1 with wasting on day 65, 1 with interstitial pneumonia on day 83, and 1 with graft rejection on day 23. In comparison, the survival of 17 DLA-identical littermates treated in the same manner was significantly better with 16 surviving without GVHD (P less than 0.01), while the survival of 54 DLA-nonidentical littermates was significantly worse with only two surviving without GVHD (P less than 0.025). These results are incompatible with the concept that solely the loci detected by mixed leukocyte culture and serotyping are responsible for GVHD. One or more additional loci appear to be involved. Knowledg e of this locus (loci) is important if marrow grafting between unrelated individuals is to be successful. However, results also indicate that an unrelated "compatible" marrow graft is more likely to succeed than a graft from an incompatible littermate.  相似文献   
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van der Weiden RM  Helmerhorst FM 《JAMA》2000,283(12):1568; author reply 1568-1568; author reply 1569
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The aim of the study was to compare the prevalence of cervical muscle pain (CMP) and myogenic temporomandibular disorders (MFP) among female dentists, high‐tech workers, and a group of subjects employed in other occupations; to investigate the associations among CMP, MFP, and bruxism in those groups; and to evaluate the influence of work‐related stress on MFP and CMP. Evaluation was based on clinical examinations of MFP and CMP and self‐reported questionnaires concerning pain and stress. The diagnosis of sleep bruxism was adapted using the validated diagnostic criteria of the American Academy of Sleep Medicine (International Classification of Sleep Disorders (ICSD‐2), 2005, Westchester, IL), whilst the diagnosis of awake bruxism was made on the basis of a questionnaire. The odds of a subject with MFP experiencing concurrent CMP or bruxism (sleep and/or awake) ranged from 2.603 to 3.077. These results suggest that high‐tech workers and dentists are at greater risk for developing temporomandibular disorders (TMDs) and CMP when compared with general occupation workers, as defined in this study. Furthermore, the associations shown here between TMDs and CMP highlight the importance of palpating neck musculature as part of any routine examination of TMD.  相似文献   
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We have studied peripheral blood lymphocytes of 117 patients with severe aplastic anemia and 237 healthy individuals for reactivity against autologous lymphocytes and/or lymphocytes from HLA-identical siblings using a 51Cr release assay. Lymphocytes from 29% of the patients exhibited reactivity against their own lymphocytes, while only 3% of lymphocytes from normal individuals showed such reactivity. Lymphocytes from 49% of the patients showed reactivity against lymphocytes from their HLA-identical siblings compared to 4% of normal individuals. Correlation existed between allogeneic and autologous reactivities (p < 0.001), suggesting a common pathway for cytotoxicity. Both reactivities showed an association with extremely low granulocyte counts (p < 0.01) and an inability of the patient's mononulcear cells to stimulate in allogeneic mixed leukocyte culture (p < 0.05) as well as an inverse correlation with time from diagnosis (p < 0.001). At least two explanations exist for the transfusion-independent autologous and allogeneic cytotoxicities: (1) they could be epiphenomena secondary to the stem cell defect, such as the loss of a cell that suppresses (or regulates) naturally occurring cytotoxic cells, or (2) they may be involved in the cause of the disease.  相似文献   
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Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
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