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81.
INTRODUCTION: Progressive multifocal leukoencephalopathy is a demyelinating disease resulting from an opportunistic infection of the central nervous system by JC papovavirus. It mostly occurs in patients with an underlying immunosuppressive disorder. In the era of acquired immunodeficiency syndrome it is observed with increasing frequency. EXEGESIS: We report the case of a non-HIV-infected patient who presented chronic lymphocytic leukemia with progressive multifocal leukoencephalopathy uncovered by both imaging and the presence of JC virus in the cerebrospinal fluid. CONCLUSION: Due to the lack of specific treatment, the disease is still rapidly progressive and fatal.  相似文献   
82.
Background  Cystic fibrosis (CF) patients have chronic pancreatic insufficiency leading to malabsorption of fat-soluble vitamins, including vitamin D which can contribute to poor skeletal health and respiratory function.
Objective  This study evaluated the prevalence of vitamin D insufficiency and its impact on bone and respiratory health in adults with CF.
Design and measurements  This was a retrospective study in which data were collected from medical records over a 2-year period. Data included patient demographics, lung function, biochemical data, bone mineral densities, X-rays and ascertainment of use of vitamin supplements. Data were collected from medical records at a single accredited CF Center. Serum 25-hydroxyvitamin D [25(OH)D] levels and bone mineral density studies were also collected.
Patients  A total of 185 adults with CF were identified with a mean age of 29 ± 9 years.
Results  The prevalence of vitamin D insufficiency [25(OH)D < 75 nmol/l] was 76%. Mean serum 25(OH)D concentrations were 58·8 ± 30 nmol/l. Use of specific vitamin D supplementation was protective against vitamin D insufficiency whereas use of multivitamins was not. There was a small, but significant, positive association between serum 25(OH)D and FEV1 per cent predicted after controlling for age, gender, BMI and race ( R 2 = 0·30, P  < 0·001). A high prevalence (27%) of vertebral fractures was detected on lateral chest X-ray.
Conclusions  The prevalence of vitamin D insufficiency and poor skeletal health is high in the US CF population. Vitamin D status appears to be positively associated with lung function. Prospective studies to examine the impact of correction of vitamin D insufficiency on skeletal and lung health in adult CF are warranted.  相似文献   
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84.
Among 810 parasitologically examined persons (1981) 277 (34%) showed positive findings. The high percentage of parasitisation in foreigners (86%) is to be explained by the in most cases aimed transfer of these patients (215 of the 810 persons). Affection with Schistosoma was recognized in 51 patients at the age of 17-47 years (means = 21.86), without Africans, and stood in the 3rd place of the distribution of frequency of the heterogeneous parasitoses. 49 of these patients came from Mozambique, 1 from Namibia and 1 from Zambia. In 51% S. haematobium was diagnosed, in 22% S. mansoni and in 27% a double infestation with the two forms of parasites. While 80% of the patients with affection of S. haematobium showed clinical symptoms (macrohaematuria, cystitis complaints), there were only 44% among the S. mansoni group. 47 patients were treated with Niridazole (Ambilhar, 25 mg/kg, 5-7 days), 2 patients with Praziquantel (Biltricide, 40 mg/kg, 1 day) and 2 other patients with Praziquantel after unsuccessful Niridazole therapy. Follow-up examinations were performed after 1, 3, 6 and 12 months. In 17% of the patients treated with Niridazole the primary treatment did not lead to cure; side effects (abdominal pain, nausea, vertigo) were observed in 55%. Praziquantel was tolerated very well. During a control period of 1 year living eggs of Schistosoma were no more proved.  相似文献   
85.
OBJECTIVE: To determine whether glutamine-supplemented parenteral nutrition improves nitrogen retention and reduces hospital morbidity compared with standard parenteral nutrition after bone marrow transplantation. DESIGN: Double-blind, randomized, controlled clinical trial. SETTING: University teaching hospital. PATIENTS: Forty-five adults receiving allogeneic bone marrow transplants for hematologic malignancies. INTERVENTION: Parenteral nutrition was initiated the day after bone marrow transplantation (day 1). The experimental solution was supplemented with L-glutamine (0.57 g/kg body weight per day) and provided estimated requirements for energy and protein. The control solution was a standard, glutamine-free, isonitrogenous, isocaloric formula. MEASUREMENTS: Nitrogen balance was determined between days 4 and 11 in the initial 23 patients. The incidence of clinical infection and microbial colonization, time until bone marrow engraftment, indices of clinical care, and other data related to hospital morbidity were recorded for all patients. RESULTS: The glutamine-supplemented patients (n = 24) were clinically similar to the controls (n = 21) at entry. Nutrient intake was similar in both groups; however, nitrogen balance was improved in the glutamine-supplemented patients relative to the controls (-1.4 +/- 0.5 g/d compared with -4.2 +/- 1.2; P = 0.002). Fewer experimental patients developed clinical infection (three compared with nine in the control group; P = 0.041), and the incidence of microbial colonization was also significantly reduced. Hospital stay was shortened in patients receiving glutamine supplementation (29 +/- 1 d compared with 36 +/- 2 d; P = 0.017). CONCLUSION: Patients receiving glutamine-supplemented parenteral nutrition after bone marrow transplantation had improved nitrogen balance, a diminished incidence of clinical infection, lower rates of microbial colonization, and shortened hospital stay compared with patients receiving standard parenteral nutrition. These effects occurred despite no differences between groups in the incidence of fever, antibiotic requirements, or time to neutrophil engraftment.  相似文献   
86.
Summary A group of 20 patients with advanced medullary (MTC) or differentiated thyroid carcinoma (DTC) received a combination chemotherapy of doxorubicin (50 mg/m2), cisplatin (60 mg/m2) and vindesine (3 mg/m2). In the 18 (10 MTC, 8 DTC) evaluable patients only 1 partial remission (in a patient with MTC) and 3 minor responses (in 3 patients with DTC) were observed. These responses lasted for 15, 9, 13, and 22 months, respectively. Three MTC patients suffered from progressive disease and no change was seen in the other 11 patients. Toxicity, including 1 severe case of cardiomyopathy, was considerable. Thus, the combination chemotherapy of doxorubicin, cisplatin and vindesine has failed to prove superior to the commonly applied doxorubicin monotherapy in patients with advanced medullary or differentiated thyroid carcinoma.Abbreviations MTC, DTC medullary and differentiated thyroid carcinoma This study was supported by a grant of the German Cancer Research Center (Tumorzentrum Heidelberg/Mannheim)  相似文献   
87.
Many recent in vitro studies have shown effects of insulin-like growth factor I (IGF I), platelet-derived growth factor (PDGF), and transforming growth factor-beta (TGF beta) on the proliferation and differential functions of bone-forming osteoblasts; however, the question whether these factors might ultimately lead to a net increase or decrease in bone formation has been difficult to assess. In this study, we have used an autoradiographic method based on the incorporation of [3H]proline into freshly synthesized bone matrix to determine the overall effects of these factors on bone matrix apposition in 21-day-old fetal rat calvariae. IGF I, PDGF, and TGF beta increased bone matrix apposition in a dose-dependent manner up to 2-fold within 48 h. In addition, they partially or completely reversed the inhibition of bone matrix apposition observed with PTH. Exogenously added TGF beta was significantly more potent than equimolar concentrations of PDGF or IGF I in stimulating bone formation. Matrix apposition was greatest when IGF I, PDGF, and TGF beta were added simultaneously to the culture medium, indicating that these factors can enhance each other in stimulating bone formation. In conclusion, our results provide direct evidence that IGF I, PDGF, and TGF beta are capable of stimulating bone formation in vitro.  相似文献   
88.
Summary Earlier findings on the pathogenesis of tumour hypoglycaemia [15] were confirmed and extended in a second patient with this disease. — A block of hepatic glucose release was found to be the main cause of hypoglycaemia in both patients suffering from large tumours of non-endocrine origin. The free fatty acid level failed to increase upon hypoglycaemia. Low free fatty acid levels correlated with an increased rate of glucose assimilation and glucose oxidation. — Immunoreactive, suppressible and nonsuppressible ILA measuredin vitro andin vivo were normal. — However, the serum of patient Z.B. inhibited lipolysis of adipose tissuein vitro to a greater extent than serum of normal subjects. This difference was no longer present after dialysis of the sera and the antilipolytic activity was now found in the diffusate. — The block of hepatic glucose release may be overcome by a pharmacological dose of intravenous glucagon. The block of hepatic glucose release is of paramount importance for the development of hypoglycaemia since the pharmacological blocking of lipolysis alone does not lead to hypoglycaemia, although it may increase glucose assimilation and glucose oxidation. — An attempt is being made to characterize further the antilipolytic substance which is present in increased amounts in the serum of patients with tumour hypoglycaemia.This work was supported by grants from the Schweizerische Nationalfonds (3336) and from the U.S. Public Health Service (AM 5387).  相似文献   
89.
Normoglycemic diabetes-prone BB/OK rats aged 33, 45 or 75 days were subjected to prophylactic insulin treatment by means of a single subcutaneous application of a sustained release insulin implant. The single application of a sustained release insulin implant decreased the incidence of diabetes or delayed the onset of the disease in BB/OK rats of all treatment groups. Prophylactic insulin administration caused a transient hypoglycemic period accompanied by an inhibition of glucose stimulated insulin secretion and a decrease of the insulin content of Langerhans' islets as detectable in vitro . Compared to islets of normoglycemic controls pancreatic islets isolated from hypoglycemic BB/OK rats within 7-21 days after the insulin application at 45 days of age displayed a decreased susceptibility of the cells to complement-dependent cytotoxicity of the monoclonal islet cell surface antibody (ICSA) K14D10 but not to the cytotoxic effect of the ICSA M3aG8. The appearance of complement-dependent antibody-mediated cytotoxicity to islet cells and pancreatic exocrine cells in serum regarded as a sign of immune dysregulation in BB/OK rats seems not to be affected by insulin prophylaxis and was detectable during hypoglycemia as well as in the subsequent normoglycemic state. In conclusion, BB/OK rats of different age can be protected from diabetes by a single application of a sustained release insulin implant. Insulin and/or hypoglycemia seem to influence the expression of cell surface antigens, thus render the islets of Langerhans less vulnerable to immune cytolysis, whereas the appearance of humoral immunological abnormalites is not affected.  相似文献   
90.
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