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Cutaneous leishmaniasis is rarely seen in the United States. Four Cuban immigrants traveled along the same route at different times from Cuba to Ecuador, then northward, including through the Darién Jungle in Panama. These patients had chronic ulcerative non-healing skin lesions and were given a diagnosis of leishmaniasis.Leishmaniasis is a vector-borne disease caused by the protozoan parasite of the genus Leishmania and is spread by the bite of sand flies from the sub-family Phlebotominae.1 There are various clinical manifestations of leishmaniasis, including cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis, and visceral leishmaniasis. Cutaneous leishmaniasis occurs at the site of the bite, with lesions forming weeks to months later starting with a papule, which then develops into a nodule or plaque-like lesion and progresses to a painless ulceration with an indurated border.We report four cases of CL caused by Leishmania (Viannia) panamensis in Cuban immigrants who traveled through the Darién Gap Jungle between Colombia and Panama on their journey north to the United States. This region has been shown to have high transmission rates of leishmaniasis,2 and, in 2012, Panama experienced an outbreak beyond expected endemic rates.3 This case series highlights a previously underappreciated immigration route to the United States for Cubans and the need to include leishmaniasis as a differential diagnosis for non-healing skin ulcers in this patient population.During May 2012–April 2013, four persons who had recently immigrated to the United States from Cuba came to the National School of Tropical Medicine at Baylor College of Medicine''s (BCM) Tropical Medicine Clinic for non-healing skin ulcers. All four persons reported a similar route of travel from Cuba to Texas (Figure 1), although at different times. Each person began their journey by flying to Quito, Ecuador, where they then traveled by bus through Colombia, passing through the cities of Pasto and Cali to Quibdo. In Quibdo, they took a short flight to Bahia Solano, Colombia, where a boat ride then transported them to Punta Ardita near the Panama border. They then traveled by foot through the thick jungle in Darién, Panama, for 5–15 days. During this time, they slept outdoors and reported numerous insect bites. Once through the Darién area, they traveled northward until they entered the United States at the Mexican border.Open in a separate windowFigure 1.Map showing immigration route of a cluster of Cuban patients with cutaneous leishmaniasis caused by Leishmania (V.) panamensis. Note the travel by foot through the thick jungle of the Darién National Park, Panama, where they likely contracted the disease.Once in the United States, the four persons sought medical care at outside clinics for skin lesions that had developed within two months after they passed though the Darién. They were treated for presumed infection with Staphylococcus aureus. The antibiotics had no therapeutic effect, and the lesions continued to grow and develop into non-healing, painless ulcers with accompanying satellite lesions. Once in Houston, Texas, the four persons were directed to the Department of Dermatology at BCM (
PatientAge, years/sexLesion location; size; presence of satellite lesions (+/−)Diagnosis and pathogenDuration of disease before initiation of treatmentTreatment course
138/FProximal right posterior arm; 5 cm; (+)CL L. (V.) panamensis3 monthsAmBisome (days 1–5, 14, 21)
246/MDistal left forearm; 2 lesions: 4 cm and 3 cm; (+)CL L. (V.) panamensis2 monthsAmBisome (days 1–5, 14, 21); then itraconazole (daily, 30 days)
343/MVertex of scalp, 8 more lesions on eyes, legs, and torso; 5 cm, other lesions 1 cm; (+)CL L. (V.) panamensis2 weeksAmBisome (days 1–5); then pentostam (daily, 20 days)
443/FLeft malar area; 1.5 cm; (+)CL L. (V.) panamensis3 monthsAmBisome (days 1–5, 14)
Open in a separate window*CL = cutaneous leishmaniasis.Patient 1 was a 38-year old woman with a three-month history of an expanding, painless, pruritic ulcer who had a 5-cm ulcer on her proximal right arm, along with several satellite lesions covered with crusts, as well as a 1.5-cm erythematous papule with central ulceration covered in crust on her right thigh. Patient 2 was a 46-year old man who had a two-month history of two erythematous, scaly plaques with central ulceration on the left forearm (Figure 2A). Patient 3 was 43-year old man with a two-month history of non-healing, tender lesions that on presentation were a 5-cm crusted nodule at the vertex of the patient''s scalp and two right parietal 1 cm papules, as well as a fluctuant nodule on his right lower leg. Patient 4 was a 43-year old woman who had a two-month history of a slowly expanding, painless lesion on her cheek, which on examination was a 1.5-cm eroded nodule on her left malar area and four papules above the main lesion (Figure 2C). All of the patients reported the lesions appearing from two weeks to two months after traveling through the Darién area. No lesions were noted before traveling through this region. The patients all denied systemic complaints including fevers, chills, night sweats, and weight loss, and were otherwise normal on physical exam. No mucosal involvement was noted in any of the patients upon exam.Open in a separate windowFigure 2.Skin ulcers of two of the four Cuban immigrants to the United States with cutaneous leishmaniasis caused by Leishmania (V.) panamensis. A, Patient 2 , showing two erythematous, scaly plaques with central ulceration and diameters of 3 cm and 4 cm on the left forearm. B, Patient 2 at six months post-treatment showing good resolution of the lesions. C, Patient 4, showing a 1.5-cm eroded nodule on left malar area and four papules above the main lesion. D, Patient 4 at three months post treatment showing with good resolution of the lesions.For each of the patients, a punch biopsy was performed by the Department of Dermatology for diagnosis by histologic analysis by BCM, and species-specific polymerase chain reaction and culture performed by the Centers for Disease Control and Prevention (Atlanta, GA). All biopsy specimens showed dense inflammatory infiltrates in the dermis with numerous histiocytes, lymphocytes, and intracellular structures within macrophages. These structures were identified as small organisms with kinetoplasts suggestive of Leishmania amastigotes. Numerous dermal plasma cells were also seen in biopsy specimens from patients 1, 2, and 4. Biopsy specimens from patient 3 showed dermal multinucleated giant cells, and scattered dermal eosinophils were observed in biopsy specimens from patient 4. Using polymerase chain reaction, PCR, CDC identified L. (V.) panamensis, a parasitic infection found in Belize, Colombia, Costa Rica, Ecuador, Honduras, Nicaragua, Panama, and Venezuela.4All the patients were treated with liposomal amphotericin B (AmBisome), 3 mg/kg/day for 5 days, followed by two infusions at the same dose on days 14 and 21 to complete a total treatment of 21 mg/kg,5 a dosing found to be effective in treating CL.6 In an attempt to minimize infusion-related reactions, the patients were pre-treated with 50 mg of diphenhydramine and 650 mg of acetaminophen, and hydrated with 500 mL of normal saline before each infusion.6 Despite this treatment, patient 1 experienced a mild self-resolving infusion-related reaction with chills and a headache. Three patients experienced an elevation of the creatinine level (two times the reference value) that resolved within days.Patients were followed-up by the Tropical Medicine Clinic over several months because healing of these ulcers is slow. Patients 1 and 4 had good resolution (Figure 2D), and patient 2 had a small, 1-cm, dry, scabbed lesion at five months post-treatment. Concern over incomplete resolution led to a 30 day course of itraconazole, 200 mg twice a day, which led to good resolution of the lesion and a leishmaniasis-negative biopsy result (Figure 2B). Patient 3 had the most extensive disease, with 13 lesions upon presentation, and during his treatment with liposomal amphotericin B, continued to have disease progression. Concern for treatment failure led to additional therapy with intravenous sodium stibogluconate (pentostam), starting at 50% of the dose (10 mg/kg/day), and increasing to 75% (15 mg/kg/day) on day 5, then 100% (20 mg/kg/day) on day 10 to complete a total of 20 days of therapy, as recommended by the Parasitic Diseases Branch of CDC (personal communication). Currently, his lesions are resolving well.Liposomal amphotericin B was chosen because all patients had extensive disease, and in the case of patient 4, the lesion was on her face, where scarring is undesirable. Liposomal amphotericin B therapy for CL has been shown clinically to be effective, with improved lesion resolution and less toxicity than sodium stibogluconate.1,612 Treatment not only promotes healing of the cutaneous lesion, but also reduces the risk of subsequent mucosal involvement.13,14 Up to 12% of CL cases are at risk of later developing mucocutaneous leishmaniasis, depending on the subspecies of Leishmania Viannia; either braziliensis or guyanensis have the highest risk.15 Mucocutaneous leishmaniasis presents as cutaneous lesions in addition to mucosal destruction, most commonly of the nose, mouth, or nasal septum. Mucosal destruction can be disfiguring and may occur years after the development of cutaneous lesions.This report highlights a previously underappreciated immigration route for Cubans through Central America, which places immigrants at risk for a number of emerging tropical diseases, including leishmaniasis. Physicians should be aware of this immigration route when treating Cuban immigrants and include leishmaniasis in the differential diagnosis when treating non-healing skin ulcers in this patient population. Liposomal amphotericin B can be a well-tolerated and efficacious treatment of CL caused by L. (V.) panamensis.  相似文献   
76.
Prevalence of gastric varices and results of sclerotherapy with N-butyl 2 cyanoacrylate for controlling acute gastric variceal bleeding   总被引:1,自引:0,他引:1  
Mumtaz K  Majid S  Shah H  Hameed K  Ahmed A  Hamid S  Jafri W 《World journal of gastroenterology : WJG》2007,13(8):1247-1251
AIM: To study the prevalence, predictors and control of bleeding following N-butyl 2 cyanoacrylate (NBC) sclerotherapy of gastric varix (GV). METHODS: We analyzed case records of 1436 patients with portal hypertension, who underwent endoscopy during the past five years for variceal screening or upper gastrointestinal (GI) bleeding. Fifty patients with bleeding GV underwent sclerotherapy with a mean of 2 mL NBC for control of bleeding. Outcome parameters were primary hemostasis (bleeding control within the first 48 h), recurrent bleeding (after 48 h of esophago- gastro-duodenoscopy) and in-hospital mortality were analyzed. RESULTS: The prevalence of GV in patients with portal hypertension was 15% (220/1436) and the incidence of bleeding was 22.7% (50/220). Out of the 50 bleeding GV patients, isolated gastric varices (IGV-I) were seen in 22 (44%), gastro-oesophageal varices (GOV) on lesser curvature (GOV-Ⅰ) in 16 (32%), and GOV on greater curvature (GOV-Ⅱ) in 15 (30%). IGV-Ⅰ was seen in 44% (22/50) patients who had bleeding as compared to 23% (39/170) who did not have bleeding (P < 0.003). Primary hemostasis was achieved with NBC in all patients. Re-bleeding occurred in 7 (14%) patients after 48 h of initial sclerotherapy. Secondary hemostasis was achieved with repeat NBC sclerotherapy in 4/7 (57%). Three patients died after repeat sclerotherapy, one during transjugular intrahepatic portosystemic stem shunt (TIPSS), one during surgery and one due to uncontrolled bleeding. Treatment failure-related mortality rate was 6% (3/50). CONCLUSION: GV can be seen in 15% of patients withportal hypertension and the incidence of bleeding is 22.7%. NBC is highly effective in controlling GV bleeding. In hospital mortality of patients with bleeding GV is 6%.  相似文献   
77.
Irritable bowel syndrome: in search of an etiology: role of Blastocystis hominis     
Yakoob J  Jafri W  Jafri N  Khan R  Islam M  Beg MA  Zaman V 《The American journal of tropical medicine and hygiene》2004,70(4):383-385
This study was designed to examine stool specimens of irritable bowel syndrome (IBS) patients for Blastocystis hominis, a common intestinal parasite. One hundred fifty patients were enrolled, 95 IBS cases and 55 controls. These patients provided a medical history, and underwent physical and laboratory evaluations that included stool microscopy and culture for B. hominis and colonoscopy. The 95 cases (51 males and 44 females) had a mean +/- SD age of 37.8 +/- 13.2 years. Stool microscopy was positive for B. hominis in 32% (30 of 95) of the cases and 7% (4 of 55) of the controls (P = 0.001). Stool culture was positive in 46% (44 of 95) of the cases and 7% (4 of 55) of the controls (P < 0.001). Stool culture for B. hominis in IBS was more sensitive than microscopy (P < 0.001). Blastocystis hominis was frequently demonstrated in the stool samples of IBS patients; however, its significance in IBS still needs to be investigated. Stool culture has a higher positive yield for B. hominis than stool microscopy.  相似文献   
78.
Increased expression of genes encoding mitochondrial proteins in papillary thyroid carcinomas.   总被引:2,自引:0,他引:2  
Dagny R Faksv?g Haugen  ?ystein Fluge  Laila J Reigstad  Jan Erik Varhaug  Johan R Lillehaug 《Thyroid》2003,13(7):613-620
  相似文献   
79.
Clinical events in high-risk hypertensive patients randomly assigned to calcium channel blocker versus angiotensin-converting enzyme inhibitor in the antihypertensive and lipid-lowering treatment to prevent heart attack trial     
Leenen FH  Nwachuku CE  Black HR  Cushman WC  Davis BR  Simpson LM  Alderman MH  Atlas SA  Basile JN  Cuyjet AB  Dart R  Felicetta JV  Grimm RH  Haywood LJ  Jafri SZ  Proschan MA  Thadani U  Whelton PK  Wright JT;Antihypertensive  Lipid-Lowering Treatment to Prevent Heart Attack Trial Collaborative Research Group 《Hypertension》2006,48(3):374-384
The Antihypertensive and Lipid-Lowering treatment to prevent Heart Attack Trial (ALLHAT) provides a unique opportunity to compare the long-term relative safety and efficacy of angiotensin-converting enzyme inhibitor and calcium channel blocker-initiated therapy in older hypertensive individuals. Patients were randomized to amlodipine (n=9048) or lisinopril (n=9054). The primary outcome was combined fatal coronary heart disease or nonfatal myocardial infarction, analyzed by intention-to-treat. Secondary outcomes included all-cause mortality, stroke, combined cardiovascular disease (CVD), end-stage renal disease (ESRD), cancer, and gastrointestinal bleeding. Mean follow-up was 4.9 years. Blood pressure control was similar in nonblacks, but not in blacks. No significant differences were found between treatment groups for the primary outcome, all-cause mortality, ESRD, or cancer. Stroke rates were higher on lisinopril in blacks (RR=1.51, 95% CI 1.22 to 1.86) but not in nonblacks (RR=1.07, 95% CI 0.89 to 1.28), and in women (RR=1.45, 95% CI 1.17 to 1.79), but not in men (RR=1.10, 95% CI 0.92 to 1.31). Rates of combined CVD were higher (RR=1.06, 95% CI 1.00 to 1.12) because of higher rates for strokes, peripheral arterial disease, and angina, which were partly offset by lower rates for heart failure (RR=0.87, 95% CI 0.78 to 0.96) on lisinopril compared with amlodipine. Gastrointestinal bleeds and angioedema were higher on lisinopril. Patients with and without baseline coronary heart disease showed similar outcome patterns. We conclude that in hypertensive patients, the risks for coronary events are similar, but for stroke, combined CVD, gastrointestinal bleeding, and angioedema are higher and for heart failure are lower for lisinopril-based compared with amlodipine-based therapy. Some, but not all, of these differences may be explained by less effective blood pressure control in the lisinopril arm.  相似文献   
80.
Clinical outcomes by race in hypertensive patients with and without the metabolic syndrome: Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)     
Wright JT  Harris-Haywood S  Pressel S  Barzilay J  Baimbridge C  Bareis CJ  Basile JN  Black HR  Dart R  Gupta AK  Hamilton BP  Einhorn PT  Haywood LJ  Jafri SZ  Louis GT  Whelton PK  Scott CL  Simmons DL  Stanford C  Davis BR 《Archives of internal medicine》2008,168(2):207-217
BACKGROUND: Antihypertensive drugs with favorable metabolic effects are advocated for first-line therapy in hypertensive patients with metabolic/cardiometabolic syndrome (MetS). We compared outcomes by race in hypertensive individuals with and without MetS treated with a thiazide-type diuretic (chlorthalidone), a calcium channel blocker (amlodipine besylate), an alpha-blocker (doxazosin mesylate), or an angiotensin-converting enzyme inhibitor (lisinopril). METHODS: A subgroup analysis of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), a randomized, double-blind hypertension treatment trial of 42 418 participants. We defined MetS as hypertension plus at least 2 of the following: fasting serum glucose level of at least 100 mg/dL, body mass index (calculated as weight in kilograms divided by height in meters squared) of at least 30, fasting triglyceride levels of at least 150 mg/dL, and high-density lipoprotein cholesterol levels of less than 40 mg/dL in men or less than 50 mg/dL in women. RESULTS: Significantly higher rates of heart failure were consistent across all treatment comparisons in those with MetS. Relative risks (RRs) were 1.50 (95% confidence interval, 1.18-1.90), 1.49 (1.17-1.90), and 1.88 (1.42-2.47) in black participants and 1.25 (1.06-1.47), 1.20 (1.01-1.41), and 1.82 (1.51-2.19) in nonblack participants for amlodipine, lisinopril, and doxazosin comparisons with chlorthalidone, respectively. Higher rates for combined cardiovascular disease were observed with lisinopril-chlorthalidone (RRs, 1.24 [1.09-1.40] and 1.10 [1.02-1.19], respectively) and doxazosin-chlorthalidone comparisons (RRs, 1.37 [1.19-1.58] and 1.18 [1.08-1.30], respectively) in black and nonblack participants with MetS. Higher rates of stroke were seen in black participants only (RR, 1.37 [1.07-1.76] for the lisinopril-chlorthalidone comparison, and RR, 1.49 [1.09-2.03] for the doxazosin-chlorthalidone comparison). Black patients with MetS also had higher rates of end-stage renal disease (RR, 1.70 [1.13-2.55]) with lisinopril compared with chlorthalidone. CONCLUSIONS: The ALLHAT findings fail to support the preference for calcium channel blockers, alpha-blockers, or angiotensin-converting enzyme inhibitors compared with thiazide-type diuretics in patients with the MetS, despite their more favorable metabolic profiles. This was particularly true for black participants.  相似文献   
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